[[LINUX PATCH v10] 0/4] Add arm pl353 smc memory and nand driver for xilinx zynq soc

[[LINUX PATCH v10] 0/4] Add arm pl353 smc memory and nand driver for xilinx zynq soc

[Naga Sureshkumar Relli]

The following patches add arm pl353 static memory controller driver and NAND
driver for Xilinx Zynq SoC. The arm pl353 smc supports two interfaces
i.e nand and NOR/SRAM memory interfaces. The current implementation supports
only a single SMC instance and nand specific configuration.

Xilinx Zynq TRM link:
http://www.xilinx.com/support/documentation/user_guides/ug585-Zynq-7000-TRM.pdf

ARM pl353 smc TRM link:
http://infocenter.arm.com/help/topic/com.arm.doc.ddi0380g/DDI0380G_smc_pl350_series_r2p1_trm.pdf

Tested Micron MT29F2G08ABAEAWP (On-die capable) and AMD/Spansion S34ML01G1.
This latest series make use of ->exec_op().
Referenced the marvel driver as pointed by Miquel.

Naga Sureshkumar Relli (4):
  Devicetree: Add pl353 smc controller devicetree binding information
  memory: pl353: Add driver for arm pl353 static memory controller
  Documentation: nand: pl353: Add documentation for controller and
    driver
  mtd: rawnand: pl353: Add basic driver for arm pl353 smc nand interface

 .../bindings/memory-controllers/pl353-smc.txt      |   41 +
 Documentation/mtd/nand/pl353-nand.txt              |   99 ++
 drivers/memory/Kconfig                             |    9 +
 drivers/memory/Makefile                            |    1 +
 drivers/memory/pl353-smc.c                         |  466 +++++++
 drivers/mtd/nand/raw/Kconfig                       |    7 +
 drivers/mtd/nand/raw/Makefile                      |    1 +
 drivers/mtd/nand/raw/pl353_nand.c                  | 1309 ++++++++++++++++++++
 include/linux/pl353-smc.h                          |   31 +
 9 files changed, 1964 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt
 create mode 100644 Documentation/mtd/nand/pl353-nand.txt
 create mode 100644 drivers/memory/pl353-smc.c
 create mode 100644 drivers/mtd/nand/raw/pl353_nand.c
 create mode 100644 include/linux/pl353-smc.h

-- 
2.7.4

[[LINUX PATCH v10] 1/4] Devicetree: Add pl353 smc controller devicetree binding information

[Naga Sureshkumar Relli]

Add pl353 static memory controller devicetree binding information.

Signed-off-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
---
Changes in v10:
 - Corrected the typos like "should be" to "Must be" and nand to NAND etc..
 - Removed padding to describe size-cells and address-cells
 - Removed timing parameters from DT, and added ->setup_data_interface() hook
   to the driver to read the SDR timings
 - Modified label name from "pl353smcc_0: pl353smcc@e000e000" to
   "smcc: memory-controller@e000e000" as suggested by Miquel
Changes in v9:
 - Addressed below comments given by Randy Dunlap and Miquel Raynal
 - Typos
 - Added extra documentation that explains the HW ECC limitation with SMC
   (Comments given to v8: https://lkml.org/lkml/2018/3/22/23)
Changes in v8:
 - None
Changes in v7:
 - Corrected clocks description
 - prefixed '#' for address and size cells
Changes in v6:
 - None
Changes in v5:
 - Removed timing properties
Changes in v4:
 - none
Changes in v3:
 - none
Changes in v2:
 - modified timing binding info as per onfi timing parameters
 - add suffix nano second as timing unit
 - modified the clock names as per the IP spec
---
 .../bindings/memory-controllers/pl353-smc.txt      | 41 ++++++++++++++++++++++
 1 file changed, 41 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt

diff --git a/Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt b/Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt
new file mode 100644
index 0000000..8b4c65e
--- /dev/null
+++ b/Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt
@@ -0,0 +1,41 @@
+Device tree bindings for ARM PL353 static memory controller
+
+PL353 static memory controller supports two kinds of memory
+interfaces.i.e NAND and SRAM/NOR interfaces.
+The actual devices are instantiated from the child nodes of pl353 smc node.
+
+Required properties:
+- compatible		: Must be "arm,pl353-smc-r2p1"
+- reg			: Controller registers map and length.
+- clock-names		: List of input clock names - "ref_clk", "aper_clk"
+			  (See clock bindings for details).
+- clocks		: Clock phandles (see clock bindings for details).
+- address-cells		: Must be 1.
+- size-cells		: Must be 1.
+
+Child nodes:
+ For NAND the "arm,pl353-nand-r2p1" and for NOR the "cfi-flash" drivers are
+supported as child nodes.
+
+for NAND partition information please refer the below file
+Documentation/devicetree/bindings/mtd/partition.txt
+
+Example:
+	smcc: memory-controller@e000e000
+			compatible = "arm,pl353-smc-r2p1"
+			clock-names = "memclk", "aclk";
+			clocks = <&clkc 11>, <&clkc 44>;
+			reg = <0xe000e000 0x1000>;
+			#address-cells = <1>;
+			#size-cells = <1>;
+			ranges;
+			nand_0: flash@e1000000 {
+				compatible = "arm,pl353-nand-r2p1"
+				reg = <0xe1000000 0x1000000>;
+				(...)
+			};
+			nor0: flash@e2000000 {
+				compatible = "cfi-flash";
+				reg = <0xe2000000 0x2000000>;
+			};
+	};
-- 
2.7.4

[[LINUX PATCH v10] 2/4] memory: pl353: Add driver for arm pl353 static memory controller

[Naga Sureshkumar Relli]

Add driver for arm pl353 static memory controller. This controller is used in
Xilinx Zynq SoC for interfacing the NAND and NOR/SRAM memory devices.

Signed-off-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
---
Changes in v10:
 - Corrected typos in commit message like xilinx to Xilinx
 - Added SoC specific compilation check in Kconfig as below
   "depends on ARCH_ZYNQ"
 - Modified return type from int to bool to the function
   pl353_smc_ecc_is_busy
 - Defined Macros for values in pl353_smc_get_ecc_val and modifed
   the logic to read ecc value from all 4 registers
 - Assinged the timeout value in pl353_smc_init_nand_interface()
   after declaration
 - Added compatibles on another line and aligned the data with them
 - Removed pl353-smc.h from platform-data and moved it to include/linux
Changes in v9:
 - Addressed the comments given by Julia Cartwright to the v8 series.
Changes in v8:
- None
Changes in v7:
- Corrected the kconfig to use tristate selection
- Corrected the GPL licence ident
- Added boundary checks for nand timing parameters
Changes in v6:
- Fixed checkpatch.pl reported warnings
Changes in v5:
- Added pl353_smc_get_clkrate function, made pl353_smc_set_cycles as public
  API
- Removed nand timing parameter initialization and moved it to nand driver
Changes in v4:
- Modified driver to support multiple instances
- Used sleep instaed of busywait for delay
Changes in v3:
- None
Changes in v2:
- Since now the timing parameters are in nano seconds, added logic to convert
  them to the cycles
---
 drivers/memory/Kconfig     |   9 +
 drivers/memory/Makefile    |   1 +
 drivers/memory/pl353-smc.c | 466 +++++++++++++++++++++++++++++++++++++++++++++
 include/linux/pl353-smc.h  |  31 +++
 4 files changed, 507 insertions(+)
 create mode 100644 drivers/memory/pl353-smc.c
 create mode 100644 include/linux/pl353-smc.h

diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig
index 19a0e83..19d5725 100644
--- a/drivers/memory/Kconfig
+++ b/drivers/memory/Kconfig
@@ -153,6 +153,15 @@ config DA8XX_DDRCTL
 	  Texas Instruments da8xx SoCs. It's used to tweak various memory
 	  controller configuration options.
 
+config PL353_SMC
+	tristate "ARM PL35X Static Memory Controller(SMC) driver"
+	default y
+	depends on ARM
+	depends on ARCH_ZYNQ
+	help
+	  This driver is for the ARM PL351/PL353 Static Memory
+	  Controller(SMC) module.
+
 source "drivers/memory/samsung/Kconfig"
 source "drivers/memory/tegra/Kconfig"
 
diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile
index 66f5524..58e794d 100644
--- a/drivers/memory/Makefile
+++ b/drivers/memory/Makefile
@@ -20,6 +20,7 @@ obj-$(CONFIG_TEGRA20_MC)	+= tegra20-mc.o
 obj-$(CONFIG_JZ4780_NEMC)	+= jz4780-nemc.o
 obj-$(CONFIG_MTK_SMI)		+= mtk-smi.o
 obj-$(CONFIG_DA8XX_DDRCTL)	+= da8xx-ddrctl.o
+obj-$(CONFIG_PL353_SMC)		+= pl353-smc.o
 
 obj-$(CONFIG_SAMSUNG_MC)	+= samsung/
 obj-$(CONFIG_TEGRA_MC)		+= tegra/
diff --git a/drivers/memory/pl353-smc.c b/drivers/memory/pl353-smc.c
new file mode 100644
index 0000000..81bebd9
--- /dev/null
+++ b/drivers/memory/pl353-smc.c
@@ -0,0 +1,466 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM PL353 SMC driver
+ *
+ * Copyright (C) 2012 Xilinx, Inc
+ * Author: Punnaiah Choudary Kalluri <punnaiah@xilinx.com>
+ * Author: Naga Sureshkumar Relli <nagasure@xilinx.com>
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/pl353-smc.h>
+
+/* Register definitions */
+#define PL353_SMC_MEMC_STATUS_OFFS	0	/* Controller status reg, RO */
+#define PL353_SMC_CFG_CLR_OFFS		0xC	/* Clear config reg, WO */
+#define PL353_SMC_DIRECT_CMD_OFFS	0x10	/* Direct command reg, WO */
+#define PL353_SMC_SET_CYCLES_OFFS	0x14	/* Set cycles register, WO */
+#define PL353_SMC_SET_OPMODE_OFFS	0x18	/* Set opmode register, WO */
+#define PL353_SMC_ECC_STATUS_OFFS	0x400	/* ECC status register */
+#define PL353_SMC_ECC_MEMCFG_OFFS	0x404	/* ECC mem config reg */
+#define PL353_SMC_ECC_MEMCMD1_OFFS	0x408	/* ECC mem cmd1 reg */
+#define PL353_SMC_ECC_MEMCMD2_OFFS	0x40C	/* ECC mem cmd2 reg */
+#define PL353_SMC_ECC_VALUE0_OFFS	0x418	/* ECC value 0 reg */
+
+/* Controller status register specific constants */
+#define PL353_SMC_MEMC_STATUS_RAW_INT_1_SHIFT	6
+
+/* Clear configuration register specific constants */
+#define PL353_SMC_CFG_CLR_INT_CLR_1	0x10
+#define PL353_SMC_CFG_CLR_ECC_INT_DIS_1	0x40
+#define PL353_SMC_CFG_CLR_INT_DIS_1	0x2
+#define PL353_SMC_CFG_CLR_DEFAULT_MASK	(PL353_SMC_CFG_CLR_INT_CLR_1 | \
+					 PL353_SMC_CFG_CLR_ECC_INT_DIS_1 | \
+					 PL353_SMC_CFG_CLR_INT_DIS_1)
+
+/* Set cycles register specific constants */
+#define PL353_SMC_SET_CYCLES_T0_MASK	0xF
+#define PL353_SMC_SET_CYCLES_T0_SHIFT	0
+#define PL353_SMC_SET_CYCLES_T1_MASK	0xF
+#define PL353_SMC_SET_CYCLES_T1_SHIFT	4
+#define PL353_SMC_SET_CYCLES_T2_MASK	0x7
+#define PL353_SMC_SET_CYCLES_T2_SHIFT	8
+#define PL353_SMC_SET_CYCLES_T3_MASK	0x7
+#define PL353_SMC_SET_CYCLES_T3_SHIFT	11
+#define PL353_SMC_SET_CYCLES_T4_MASK	0x7
+#define PL353_SMC_SET_CYCLES_T4_SHIFT	14
+#define PL353_SMC_SET_CYCLES_T5_MASK	0x7
+#define PL353_SMC_SET_CYCLES_T5_SHIFT	17
+#define PL353_SMC_SET_CYCLES_T6_MASK	0xF
+#define PL353_SMC_SET_CYCLES_T6_SHIFT	20
+
+/* ECC status register specific constants */
+#define PL353_SMC_ECC_STATUS_BUSY	BIT(6)
+#define PL353_SMC_ECC_REG_SIZE_OFFS	4
+
+/* ECC memory config register specific constants */
+#define PL353_SMC_ECC_MEMCFG_MODE_MASK	0xC
+#define PL353_SMC_ECC_MEMCFG_MODE_SHIFT	2
+#define PL353_SMC_ECC_MEMCFG_PGSIZE_MASK	0xC
+
+#define PL353_SMC_DC_UPT_NAND_REGS	((4 << 23) |	/* CS: NAND chip */ \
+				 (2 << 21))	/* UpdateRegs operation */
+
+#define PL353_NAND_ECC_CMD1	((0x80)       |	/* Write command */ \
+				 (0 << 8)     |	/* Read command */ \
+				 (0x30 << 16) |	/* Read End command */ \
+				 (1 << 24))	/* Read End command calid */
+
+#define PL353_NAND_ECC_CMD2	((0x85)	      |	/* Write col change cmd */ \
+				 (5 << 8)     |	/* Read col change cmd */ \
+				 (0xE0 << 16) |	/* Read col change end cmd */ \
+				 (1 << 24)) /* Read col change end cmd valid */
+#define PL353_NAND_ECC_BUSY_TIMEOUT	(1 * HZ)
+/**
+ * struct pl353_smc_data - Private smc driver structure
+ * @memclk:		Pointer to the peripheral clock
+ * @aclk:		Pointer to the APER clock
+ */
+struct pl353_smc_data {
+	struct clk		*memclk;
+	struct clk		*aclk;
+};
+
+/* SMC virtual register base */
+static void __iomem *pl353_smc_base;
+
+/**
+ * pl353_smc_set_buswidth - Set memory buswidth
+ * @bw:	Memory buswidth (8 | 16)
+ * Return: 0 on success or negative errno.
+ */
+int pl353_smc_set_buswidth(unsigned int bw)
+{
+	if (bw != PL353_SMC_MEM_WIDTH_8  && bw != PL353_SMC_MEM_WIDTH_16)
+		return -EINVAL;
+
+	writel(bw, pl353_smc_base + PL353_SMC_SET_OPMODE_OFFS);
+	writel(PL353_SMC_DC_UPT_NAND_REGS, pl353_smc_base +
+	       PL353_SMC_DIRECT_CMD_OFFS);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(pl353_smc_set_buswidth);
+
+/**
+ * pl353_smc_set_cycles - Set memory timing parameters
+ * @t0:	t_rc		read cycle time
+ * @t1:	t_wc		write cycle time
+ * @t2:	t_rea/t_ceoe	output enable assertion delay
+ * @t3:	t_wp		write enable deassertion delay
+ * @t4:	t_clr/t_pc	page cycle time
+ * @t5:	t_ar/t_ta	ID read time/turnaround time
+ * @t6:	t_rr		busy to RE timing
+ *
+ * Sets NAND chip specific timing parameters.
+ */
+void pl353_smc_set_cycles(u32 t0, u32 t1, u32 t2, u32 t3, u32
+			      t4, u32 t5, u32 t6)
+{
+
+	/*
+	 * Set write pulse timing. This one is easy to extract:
+	 *
+	 * NWE_PULSE = tWP
+	 */
+	t0 &= PL353_SMC_SET_CYCLES_T0_MASK;
+	t1 = (t1 & PL353_SMC_SET_CYCLES_T1_MASK) <<
+			PL353_SMC_SET_CYCLES_T1_SHIFT;
+	t2 = (t2 & PL353_SMC_SET_CYCLES_T2_MASK) <<
+			PL353_SMC_SET_CYCLES_T2_SHIFT;
+	t3 = (t3 & PL353_SMC_SET_CYCLES_T3_MASK) <<
+			PL353_SMC_SET_CYCLES_T3_SHIFT;
+	t4 = (t4 & PL353_SMC_SET_CYCLES_T4_MASK) <<
+			PL353_SMC_SET_CYCLES_T4_SHIFT;
+	t5 = (t5 & PL353_SMC_SET_CYCLES_T5_MASK) <<
+			PL353_SMC_SET_CYCLES_T5_SHIFT;
+	t6 = (t6 & PL353_SMC_SET_CYCLES_T6_MASK) <<
+			PL353_SMC_SET_CYCLES_T6_SHIFT;
+
+	t0 |= t1 | t2 | t3 | t4 | t5 | t6;
+
+	writel(t0, pl353_smc_base + PL353_SMC_SET_CYCLES_OFFS);
+	writel(PL353_SMC_DC_UPT_NAND_REGS, pl353_smc_base +
+	       PL353_SMC_DIRECT_CMD_OFFS);
+}
+EXPORT_SYMBOL_GPL(pl353_smc_set_cycles);
+
+/**
+ * pl353_smc_ecc_is_busy - Read ecc busy flag
+ * Return: the ecc_status bit from the ecc_status register. 1 = busy, 0 = idle
+ */
+bool pl353_smc_ecc_is_busy(void)
+{
+	return ((readl(pl353_smc_base + PL353_SMC_ECC_STATUS_OFFS) &
+		  PL353_SMC_ECC_STATUS_BUSY) == PL353_SMC_ECC_STATUS_BUSY);
+}
+EXPORT_SYMBOL_GPL(pl353_smc_ecc_is_busy);
+
+/**
+ * pl353_smc_get_ecc_val - Read ecc_valueN registers
+ * @ecc_reg:	Index of the ecc_value reg (0..3)
+ * Return: the content of the requested ecc_value register.
+ *
+ * There are four valid ecc_value registers. The argument is truncated to stay
+ * within this valid boundary.
+ */
+u32 pl353_smc_get_ecc_val(int ecc_reg)
+{
+	u32 addr, reg;
+
+	addr = PL353_SMC_ECC_VALUE0_OFFS +
+		(ecc_reg * PL353_SMC_ECC_REG_SIZE_OFFS);
+	reg = readl(pl353_smc_base + addr);
+
+	return reg;
+}
+EXPORT_SYMBOL_GPL(pl353_smc_get_ecc_val);
+
+/**
+ * pl353_smc_get_nand_int_status_raw - Get NAND interrupt status bit
+ * Return: the raw_int_status1 bit from the memc_status register
+ */
+int pl353_smc_get_nand_int_status_raw(void)
+{
+	u32 reg;
+
+	reg = readl(pl353_smc_base + PL353_SMC_MEMC_STATUS_OFFS);
+	reg >>= PL353_SMC_MEMC_STATUS_RAW_INT_1_SHIFT;
+	reg &= 1;
+
+	return reg;
+}
+EXPORT_SYMBOL_GPL(pl353_smc_get_nand_int_status_raw);
+
+/**
+ * pl353_smc_clr_nand_int - Clear NAND interrupt
+ */
+void pl353_smc_clr_nand_int(void)
+{
+	writel(PL353_SMC_CFG_CLR_INT_CLR_1,
+	       pl353_smc_base + PL353_SMC_CFG_CLR_OFFS);
+}
+EXPORT_SYMBOL_GPL(pl353_smc_clr_nand_int);
+
+/**
+ * pl353_smc_set_ecc_mode - Set SMC ECC mode
+ * @mode:	ECC mode (BYPASS, APB, MEM)
+ * Return: 0 on success or negative errno.
+ */
+int pl353_smc_set_ecc_mode(enum pl353_smc_ecc_mode mode)
+{
+	u32 reg;
+	int ret = 0;
+
+	switch (mode) {
+	case PL353_SMC_ECCMODE_BYPASS:
+	case PL353_SMC_ECCMODE_APB:
+	case PL353_SMC_ECCMODE_MEM:
+
+		reg = readl(pl353_smc_base + PL353_SMC_ECC_MEMCFG_OFFS);
+		reg &= ~PL353_SMC_ECC_MEMCFG_MODE_MASK;
+		reg |= mode << PL353_SMC_ECC_MEMCFG_MODE_SHIFT;
+		writel(reg, pl353_smc_base + PL353_SMC_ECC_MEMCFG_OFFS);
+
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(pl353_smc_set_ecc_mode);
+
+/**
+ * pl353_smc_set_ecc_pg_size - Set SMC ECC page size
+ * @pg_sz:	ECC page size
+ * Return: 0 on success or negative errno.
+ */
+int pl353_smc_set_ecc_pg_size(unsigned int pg_sz)
+{
+	u32 reg, sz;
+
+	switch (pg_sz) {
+	case 0:
+		sz = 0;
+		break;
+	case SZ_512:
+		sz = 1;
+		break;
+	case SZ_1K:
+		sz = 2;
+		break;
+	case SZ_2K:
+		sz = 3;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	reg = readl(pl353_smc_base + PL353_SMC_ECC_MEMCFG_OFFS);
+	reg &= ~PL353_SMC_ECC_MEMCFG_PGSIZE_MASK;
+	reg |= sz;
+	writel(reg, pl353_smc_base + PL353_SMC_ECC_MEMCFG_OFFS);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(pl353_smc_set_ecc_pg_size);
+
+static int __maybe_unused pl353_smc_suspend(struct device *dev)
+{
+	struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
+
+	clk_disable(pl353_smc->memclk);
+	clk_disable(pl353_smc->aclk);
+
+	return 0;
+}
+
+static int __maybe_unused pl353_smc_resume(struct device *dev)
+{
+	int ret;
+	struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
+
+	ret = clk_enable(pl353_smc->aclk);
+	if (ret) {
+		dev_err(dev, "Cannot enable axi domain clock.\n");
+		return ret;
+	}
+
+	ret = clk_enable(pl353_smc->memclk);
+	if (ret) {
+		dev_err(dev, "Cannot enable memory clock.\n");
+		clk_disable(pl353_smc->aclk);
+		return ret;
+	}
+
+	return ret;
+}
+
+static SIMPLE_DEV_PM_OPS(pl353_smc_dev_pm_ops, pl353_smc_suspend,
+			 pl353_smc_resume);
+
+/**
+ * pl353_smc_init_nand_interface - Initialize the NAND interface
+ * @pdev:	Pointer to the platform_device struct
+ * @nand_node:	Pointer to the pl353_nand device_node struct
+ */
+void pl353_smc_init_nand_interface(struct platform_device *pdev,
+					struct device_node *nand_node)
+{
+	unsigned long timeout;
+
+	pl353_smc_set_buswidth(PL353_SMC_MEM_WIDTH_8);
+	writel(PL353_SMC_CFG_CLR_INT_CLR_1,
+	       pl353_smc_base + PL353_SMC_CFG_CLR_OFFS);
+	writel(PL353_SMC_DC_UPT_NAND_REGS, pl353_smc_base +
+	       PL353_SMC_DIRECT_CMD_OFFS);
+
+	timeout = jiffies + PL353_NAND_ECC_BUSY_TIMEOUT;
+	/* Wait till the ECC operation is complete */
+	do {
+		if (pl353_smc_ecc_is_busy())
+			cpu_relax();
+		else
+			break;
+	} while (!time_after_eq(jiffies, timeout));
+
+	if (time_after_eq(jiffies, timeout))
+		return;
+
+	writel(PL353_NAND_ECC_CMD1,
+	       pl353_smc_base + PL353_SMC_ECC_MEMCMD1_OFFS);
+	writel(PL353_NAND_ECC_CMD2,
+	       pl353_smc_base + PL353_SMC_ECC_MEMCMD2_OFFS);
+}
+
+static const struct of_device_id pl353_smc_supported_children[] = {
+	{
+		.compatible = "cfi-flash"
+	},
+	{
+		.compatible = "arm,pl353-nand-r2p1",
+		.data = pl353_smc_init_nand_interface
+	},
+	{}
+};
+
+static int pl353_smc_probe(struct platform_device *pdev)
+{
+	struct pl353_smc_data *pl353_smc;
+	struct device_node *child;
+	struct resource *res;
+	int err;
+	struct device_node *of_node = pdev->dev.of_node;
+	void (*init)(struct platform_device *pdev,
+		     struct device_node *nand_node);
+	const struct of_device_id *match = NULL;
+
+	pl353_smc = devm_kzalloc(&pdev->dev, sizeof(*pl353_smc), GFP_KERNEL);
+	if (!pl353_smc)
+		return -ENOMEM;
+
+	/* Get the NAND controller virtual address */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	pl353_smc_base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(pl353_smc_base))
+		return PTR_ERR(pl353_smc_base);
+
+	pl353_smc->aclk = devm_clk_get(&pdev->dev, "aclk");
+	if (IS_ERR(pl353_smc->aclk)) {
+		dev_err(&pdev->dev, "aclk clock not found.\n");
+		return PTR_ERR(pl353_smc->aclk);
+	}
+
+	pl353_smc->memclk = devm_clk_get(&pdev->dev, "memclk");
+	if (IS_ERR(pl353_smc->memclk)) {
+		dev_err(&pdev->dev, "memclk clock not found.\n");
+		return PTR_ERR(pl353_smc->memclk);
+	}
+
+	err = clk_prepare_enable(pl353_smc->aclk);
+	if (err) {
+		dev_err(&pdev->dev, "Unable to enable AXI clock.\n");
+		return err;
+	}
+
+	err = clk_prepare_enable(pl353_smc->memclk);
+	if (err) {
+		dev_err(&pdev->dev, "Unable to enable memory clock.\n");
+		goto out_clk_dis_aper;
+	}
+
+	platform_set_drvdata(pdev, pl353_smc);
+
+	/* clear interrupts */
+	writel(PL353_SMC_CFG_CLR_DEFAULT_MASK,
+	       pl353_smc_base + PL353_SMC_CFG_CLR_OFFS);
+
+	/* Find compatible children. Only a single child is supported */
+	for_each_available_child_of_node(of_node, child) {
+		match = of_match_node(pl353_smc_supported_children, child);
+		if (!match) {
+			dev_warn(&pdev->dev, "unsupported child node\n");
+			continue;
+		}
+		break;
+	}
+	if (!match) {
+		dev_err(&pdev->dev, "no matching children\n");
+		goto out_clk_disable;
+	}
+
+	init = match->data;
+	if (init)
+		init(pdev, child);
+	of_platform_device_create(child, NULL, &pdev->dev);
+
+	return 0;
+
+out_clk_disable:
+	clk_disable_unprepare(pl353_smc->memclk);
+out_clk_dis_aper:
+	clk_disable_unprepare(pl353_smc->aclk);
+
+	return err;
+}
+
+static int pl353_smc_remove(struct platform_device *pdev)
+{
+	struct pl353_smc_data *pl353_smc = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(pl353_smc->memclk);
+	clk_disable_unprepare(pl353_smc->aclk);
+
+	return 0;
+}
+
+/* Match table for device tree binding */
+static const struct of_device_id pl353_smc_of_match[] = {
+	{ .compatible = "arm,pl353-smc-r2p1" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, pl353_smc_of_match);
+
+static struct platform_driver pl353_smc_driver = {
+	.probe		= pl353_smc_probe,
+	.remove		= pl353_smc_remove,
+	.driver		= {
+		.name	= "pl353-smc",
+		.pm	= &pl353_smc_dev_pm_ops,
+		.of_match_table = pl353_smc_of_match,
+	},
+};
+
+module_platform_driver(pl353_smc_driver);
+
+MODULE_AUTHOR("Xilinx, Inc.");
+MODULE_DESCRIPTION("ARM PL353 SMC Driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/pl353-smc.h b/include/linux/pl353-smc.h
new file mode 100644
index 0000000..67b0f8b
--- /dev/null
+++ b/include/linux/pl353-smc.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * ARM PL353 SMC Driver Header
+ *
+ * Copyright (C) 2017 Xilinx, Inc
+ */
+
+#ifndef __LINUX_MEMORY_PL353_SMC_H
+#define __LINUX_MEMORY_PL353_SMC_H
+
+enum pl353_smc_ecc_mode {
+	PL353_SMC_ECCMODE_BYPASS = 0,
+	PL353_SMC_ECCMODE_APB = 1,
+	PL353_SMC_ECCMODE_MEM = 2
+};
+
+enum pl353_smc_mem_width {
+	PL353_SMC_MEM_WIDTH_8 = 0,
+	PL353_SMC_MEM_WIDTH_16 = 1
+};
+
+u32 pl353_smc_get_ecc_val(int ecc_reg);
+bool pl353_smc_ecc_is_busy(void);
+int pl353_smc_get_nand_int_status_raw(void);
+void pl353_smc_clr_nand_int(void);
+int pl353_smc_set_ecc_mode(enum pl353_smc_ecc_mode mode);
+int pl353_smc_set_ecc_pg_size(unsigned int pg_sz);
+int pl353_smc_set_buswidth(unsigned int bw);
+void pl353_smc_set_cycles(u32 t0, u32 t1, u32 t2, u32 t3, u32 t4, u32 t5,
+			  u32 t6);
+#endif
-- 
2.7.4

[[LINUX PATCH v10] 3/4] Documentation: nand: pl353: Add documentation for controller and driver

[Naga Sureshkumar Relli]

Added notes about the controller and driver.

Signed-off-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
---
Changes in v10:
 - None
Changes in v9:
 - Addressed the comments given by Miquel and Randy
Changes in v8
 - None
Changes in v7:
- None
Changes in v6:
- None
Changes in v5:
- Fixed the review comments
Changes in v4:
- None
---
 Documentation/mtd/nand/pl353-nand.txt | 99 +++++++++++++++++++++++++++++++++++
 1 file changed, 99 insertions(+)
 create mode 100644 Documentation/mtd/nand/pl353-nand.txt

diff --git a/Documentation/mtd/nand/pl353-nand.txt b/Documentation/mtd/nand/pl353-nand.txt
new file mode 100644
index 0000000..c352c87
--- /dev/null
+++ b/Documentation/mtd/nand/pl353-nand.txt
@@ -0,0 +1,99 @@
+This document provides some notes about the ARM pl353 SMC controller used in
+Zynq SOC and confined to NAND specific details.
+
+Overview of the controller
+==========================
+	The SMC (PL353) supports two memory interfaces:
+	Interface 0 type SRAM.
+	Interface 1 type NAND.
+	This configuration supports the following configurable options:
+	   . 32-bit or 64-bit AXI data width
+	   . 8-bit, 16-bit, or 32-bit memory data width for interface 0
+	   . 8-bit, or 16-bit memory data width for interface 1
+	   . 1-4 chip selects on each interface
+	   . SLC ECC block for interface 1
+
+For more information, refer the below link for TRM
+http://infocenter.arm.com/help/topic/com.arm.doc.ddi0380g/DDI0380G_smc_pl350_series_r2p1_trm.pdf
+
+NAND memory accesses
+====================
+	. Two phase NAND accesses
+	. NAND command phase transfers
+	. NAND data phase transfers
+
+Two phase NAND accesses
+	The SMC defines two phases of commands when transferring data to or from
+NAND flash.
+
+Command phase
+	Commands and optional address information are written to the NAND flash.
+The command and address can be associated with either a data phase operation to
+write to or read from the array, or a status/ID register transfer.
+
+Data phase
+ Data is either written to or read from the NAND flash. This data can be either
+data transferred to or from the array, or status/ID register information.
+
+NAND AXI address setup
+       AXI address      Command phase      Data phase
+	[31:24]         Chip address       Chip address
+	[23]            NoOfAddCycles_2    Reserved
+	[22]            NoOfAddCycles_1    Reserved
+	[21]            NoOfAddCycles_0    ClearCS
+	[20]            End command valid  End command valid
+	[19]            0                  1
+	[18:11]         End command        End command
+	[10:3]          Start command      [10] ECC Last
+					   [9:3] Reserved
+	[2:0]           Reserved           Reserved
+
+ECC
+===
+    It operates on a number of 512 byte blocks of NAND memory and can be
+programmed to store the ECC codes after the data in memory. For writes,
+the ECC is written to the spare area of the page. For reads, the result of
+a block ECC check are made available to the device driver.
+
+------------------------------------------------------------------------
+|               n * 512 blocks                  | extra  | ecc    |     |
+|                                               | block  | codes  |     |
+------------------------------------------------------------------------
+
+The ECC calculation uses a simple Hamming code, using 1-bit correction 2-bit
+detection. It starts when a valid read or write command with a 512 byte aligned
+address is detected on the memory interface.
+
+Driver details
+==============
+	The NAND driver has dependency with the pl353_smc memory controller
+driver for initializing the NAND timing parameters, bus width, ECC modes,
+control and status information.
+
+Since the controller expects that the chip select bit would be cleared for the
+last data transfer i.e last 4 data bytes, the existing nand page
+read/write routines for soft ECC and ECC none modes will not work. So, in order
+to make this driver work, it always updates the ECC mode as HW ECC and
+implements the page read/write functions for supporting the SW ECC.
+i.e. There is a limitation in SMC controller, that we must set ECC LAST on
+last data phase access, to tell ECC block not to expect any data further.
+Ex:  When number of ECC STEPS are 4, then till 3 we will write to flash
+using SMC with HW ECC enabled. And for the last ECC STEP, we will subtract
+4bytes from page size, and will initiate a transfer. And the remaining 4 as
+one more transfer with ECC_LAST bit set in NAND data phase register to notify
+ECC block not to expect any more data. The last block should be align with end
+of 512 byte block. Because of this limitation, we are not using core routines.
+
+HW ECC mode:
+	Up to 2K page size is supported and beyond that it returns
+-ENOTSUPPORT error. If the flash has on-die ECC controller then the
+priority is given to the on-die ECC controller. Also the current
+implementation has support for up to 64 bytes of OOB data.
+
+SW ECC mode:
+	It supports all the page sizes. But since, Zynq SOC bootrom uses
+HW ECC for the devices that have page <= 2K. so, When the kernel is not
+aware of the ECC mode, it uses HW ECC by default.
+
+For devicetree binding information please refer to the below dt binding file
+Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt.
-- 
2.7.4

[[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm pl353 smc nand interface

[Naga Sureshkumar Relli]

Add driver for arm pl353 static memory controller nand interface with HW ECC
support. This controller is used in Xilinx Zynq SoC for interfacing the NAND
flash memory.

Signed-off-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
---
Changes in 10:
 - Typos correction like nand to NAND and soc to SOC etc..
 - Defined macros for the values in pl353_nand_calculate_hwecc()
 - Modifed ecc_status from int to char in pl353_nand_calculate_hwecc()
 - Changed the return type form int to bool to the function
   onehot()
 - Removed udelay(1000) in pl353_cmd_function, as it is not required
 - Dropped ecc->hwctl = NULL in pl353_ecc_init()
 - Added an error message in pl353_ecc_init(), when there is no matching
   oobsize
 - Changed the variable from xnand to xnfc
 - Added logic to get mtd->name from DT, if it is specified in DT
Changes in v9:
 - Addressed the below comments given by Miquel
 - instead of using pl353_nand_write32, use directly writel_relaxed
 - Fixed check patch warnings
 - Renamed write_buf/read_buf to write_data_op/read_data_op
 - use BIT macro instead of 1 << nr
 - Use NAND_ROW_ADDR_3 flag
 - Use nand_wait_ready()
 - Removed swecc functions
 - Use address cycles as per size, instead of reading it from Parameter page
 - Instead of writing too many patterns, use optional property
Changes in v8:
 - Added exec_op() implementation
 - Fixed the below v7 review comments
 - removed mtd_info from pl353_nand_info struct
 - Corrected ecc layout offsets
 - Added on-die ecc support
Changes in v7:
 - Currently not implemented the memclk rate adjustments. I will
   look into this later and once the basic driver is accepted.
 - Fixed GPL licence ident
Changes in v6:
 - Fixed the checkpatch.pl reported warnings
 - Using the address cycles information from the onfi param page
   earlier it is hardcoded to 5 in driver
Changes in v5:
 - Configure the nand timing parameters as per the onfi spec Changes in v4:
 - Updated the driver to sync with pl353_smc driver APIs
Changes in v3:
 - implemented the proper error codes
 - further breakdown this patch to multiple sets
 - added the controller and driver details to Documentation section
 - updated the licenece to GPLv2
 - reorganized the pl353_nand_ecc_init function
Changes in v2:
 - use "depends on" rather than "select" option in kconfig
 - remove unused variable parts
---
 drivers/mtd/nand/raw/Kconfig      |    7 +
 drivers/mtd/nand/raw/Makefile     |    1 +
 drivers/mtd/nand/raw/pl353_nand.c | 1309 +++++++++++++++++++++++++++++++++++++
 3 files changed, 1317 insertions(+)
 create mode 100644 drivers/mtd/nand/raw/pl353_nand.c

diff --git a/drivers/mtd/nand/raw/Kconfig b/drivers/mtd/nand/raw/Kconfig
index 6871ff0..1c5d528 100644
--- a/drivers/mtd/nand/raw/Kconfig
+++ b/drivers/mtd/nand/raw/Kconfig
@@ -530,4 +530,11 @@ config MTD_NAND_MTK
 	  Enables support for NAND controller on MTK SoCs.
 	  This controller is found on mt27xx, mt81xx, mt65xx SoCs.
 
+config MTD_NAND_PL353
+	tristate "ARM Pl353 NAND flash driver"
+	depends on MTD_NAND && ARM
+	depends on PL353_SMC
+	help
+	  Enables support for PrimeCell Static Memory Controller PL353.
+
 endif # MTD_NAND
diff --git a/drivers/mtd/nand/raw/Makefile b/drivers/mtd/nand/raw/Makefile
index 165b7ef..1c702e1 100644
--- a/drivers/mtd/nand/raw/Makefile
+++ b/drivers/mtd/nand/raw/Makefile
@@ -56,6 +56,7 @@ obj-$(CONFIG_MTD_NAND_HISI504)	        += hisi504_nand.o
 obj-$(CONFIG_MTD_NAND_BRCMNAND)		+= brcmnand/
 obj-$(CONFIG_MTD_NAND_QCOM)		+= qcom_nandc.o
 obj-$(CONFIG_MTD_NAND_MTK)		+= mtk_ecc.o mtk_nand.o
+obj-$(CONFIG_MTD_NAND_PL353)		+= pl353_nand.o
 
 nand-objs := nand_base.o nand_bbt.o nand_timings.o nand_ids.o
 nand-objs += nand_amd.o
diff --git a/drivers/mtd/nand/raw/pl353_nand.c b/drivers/mtd/nand/raw/pl353_nand.c
new file mode 100644
index 0000000..3a0acbd
--- /dev/null
+++ b/drivers/mtd/nand/raw/pl353_nand.c
@@ -0,0 +1,1309 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM PL353 NAND flash controller driver
+ *
+ * Copyright (C) 2017 Xilinx, Inc
+ * Author: Punnaiah chowdary kalluri <punnaiah@xilinx.com>
+ * Author: Naga Sureshkumar Relli <nagasure@xilinx.com>
+ *
+ */
+
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/rawnand.h>
+#include <linux/mtd/nand_ecc.h>
+#include <linux/mtd/partitions.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/pl353-smc.h>
+#include <linux/clk.h>
+
+#define PL353_NAND_DRIVER_NAME "pl353-nand"
+
+/* NAND flash driver defines */
+#define PL353_NAND_CMD_PHASE	1	/* End command valid in command phase */
+#define PL353_NAND_DATA_PHASE	2	/* End command valid in data phase */
+#define PL353_NAND_ECC_SIZE	512	/* Size of data for ECC operation */
+
+/* Flash memory controller operating parameters */
+
+#define PL353_NAND_ECC_CONFIG	(BIT(4)  |	/* ECC read at end of page */ \
+				 (0 << 5))	/* No Jumping */
+
+/* AXI Address definitions */
+#define START_CMD_SHIFT		3
+#define END_CMD_SHIFT		11
+#define END_CMD_VALID_SHIFT	20
+#define ADDR_CYCLES_SHIFT	21
+#define CLEAR_CS_SHIFT		21
+#define ECC_LAST_SHIFT		10
+#define COMMAND_PHASE		(0 << 19)
+#define DATA_PHASE		BIT(19)
+
+#define PL353_NAND_ECC_LAST	BIT(ECC_LAST_SHIFT)	/* Set ECC_Last */
+#define PL353_NAND_CLEAR_CS	BIT(CLEAR_CS_SHIFT)	/* Clear chip select */
+
+#define ONDIE_ECC_FEATURE_ADDR	0x90
+#define PL353_NAND_ECC_BUSY_TIMEOUT	(1 * HZ)
+#define PL353_NAND_DEV_BUSY_TIMEOUT	(1 * HZ)
+#define PL353_NAND_LAST_TRANSFER_LENGTH	4
+#define PL353_NAND_ECC_VALID_SHIFT	24
+#define PL353_NAND_ECC_VALID_MASK	0x40
+
+struct pl353_nfc_op {
+	u32 cmnds[4];
+	u32 thirdrow;
+	u32 type;
+	u32 end_cmd;
+	u32 addrs;
+	bool wait;
+	u32 len;
+	u32 naddrs;
+	unsigned int data_instr_idx;
+	const struct nand_op_instr *data_instr;
+	unsigned int rdy_timeout_ms;
+	unsigned int rdy_delay_ns;
+	unsigned int data_delay_ns;
+	unsigned int cle_ale_delay_ns;
+	u32 addr5;
+	u32 addr6;
+};
+
+/**
+ * struct pl353_nand_info - Defines the NAND flash driver instance
+ * @chip:		NAND chip information structure
+ * @nand_base:		Virtual address of the NAND flash device
+ * @end_cmd_pending:	End command is pending
+ * @end_cmd:		End command
+ * @row_addr_cycles:	Row address cycles
+ * @col_addr_cycles:	Column address cycles
+ * @address:		Page address
+ * @cmd_pending:	More command is needed
+ */
+struct pl353_nand_info {
+	struct nand_chip chip;
+	struct device *dev;
+	void __iomem *nand_base;
+	unsigned long end_cmd_pending;
+	unsigned long end_cmd;
+	u8 addr_cycles;
+	u32 address;
+	u32 cmd_pending;
+	struct completion complete;
+	struct clk *mclk;
+
+};
+
+static int pl353_ecc_ooblayout16_ecc(struct mtd_info *mtd, int section,
+				     struct mtd_oob_region *oobregion)
+{
+	struct nand_chip *chip = mtd_to_nand(mtd);
+
+	if (section >= chip->ecc.steps)
+		return -ERANGE;
+
+	oobregion->offset = (section * chip->ecc.bytes);
+	oobregion->length = chip->ecc.bytes;
+
+	return 0;
+}
+
+static int pl353_ecc_ooblayout16_free(struct mtd_info *mtd, int section,
+				      struct mtd_oob_region *oobregion)
+{
+	struct nand_chip *chip = mtd_to_nand(mtd);
+
+	if (section >= chip->ecc.steps)
+		return -ERANGE;
+
+	oobregion->offset = (section * chip->ecc.bytes) + 8;
+	oobregion->length = 8;
+
+	return 0;
+}
+
+static const struct mtd_ooblayout_ops pl353_ecc_ooblayout16_ops = {
+	.ecc = pl353_ecc_ooblayout16_ecc,
+	.free = pl353_ecc_ooblayout16_free,
+};
+
+static int pl353_ecc_ooblayout64_ecc(struct mtd_info *mtd, int section,
+				     struct mtd_oob_region *oobregion)
+{
+	struct nand_chip *chip = mtd_to_nand(mtd);
+
+	if (section >= chip->ecc.steps)
+		return -ERANGE;
+
+	oobregion->offset = (section * chip->ecc.bytes) + 52;
+	oobregion->length = chip->ecc.bytes;
+
+	return 0;
+}
+
+static int pl353_ecc_ooblayout64_free(struct mtd_info *mtd, int section,
+				      struct mtd_oob_region *oobregion)
+{
+	struct nand_chip *chip = mtd_to_nand(mtd);
+
+	if (section)
+		return -ERANGE;
+
+	if (section >= chip->ecc.steps)
+		return -ERANGE;
+
+	oobregion->offset = (section * chip->ecc.bytes) + 2;
+	oobregion->length = 50;
+
+	return 0;
+}
+
+static const struct mtd_ooblayout_ops pl353_ecc_ooblayout64_ops = {
+	.ecc = pl353_ecc_ooblayout64_ecc,
+	.free = pl353_ecc_ooblayout64_free,
+};
+
+/* Generic flash bbt decriptors */
+static u8 bbt_pattern[] = { 'B', 'b', 't', '0' };
+static u8 mirror_pattern[] = { '1', 't', 'b', 'B' };
+
+static struct nand_bbt_descr bbt_main_descr = {
+	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
+		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
+	.offs = 4,
+	.len = 4,
+	.veroffs = 20,
+	.maxblocks = 4,
+	.pattern = bbt_pattern
+};
+
+static struct nand_bbt_descr bbt_mirror_descr = {
+	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
+		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
+	.offs = 4,
+	.len = 4,
+	.veroffs = 20,
+	.maxblocks = 4,
+	.pattern = mirror_pattern
+};
+
+/**
+ * pl353_nand_read_data_op - read chip data into buffer
+ * @chip:	Pointer to the NAND chip info structure
+ * @in:		Pointer to the buffer to store read data
+ * @len:	Number of bytes to read
+ * Return:	Always return zero
+ */
+static int pl353_nand_read_data_op(struct nand_chip *chip,
+				   u8 *in,
+				   unsigned int len)
+{
+	int i;
+
+	if (IS_ALIGNED((uint32_t)in, sizeof(uint32_t)) &&
+	    IS_ALIGNED(len, sizeof(uint32_t))) {
+		u32 *ptr = (u32 *)in;
+
+		len /= 4;
+		for (i = 0; i < len; i++)
+			ptr[i] = readl(chip->IO_ADDR_R);
+	} else {
+		for (i = 0; i < len; i++)
+			in[i] = readb(chip->IO_ADDR_R);
+	}
+
+	return 0;
+}
+
+/**
+ * pl353_nand_write_buf - write buffer to chip
+ * @mtd:	Pointer to the mtd info structure
+ * @buf:	Pointer to the buffer to store write data
+ * @len:	Number of bytes to write
+ */
+static void pl353_nand_write_data_op(struct mtd_info *mtd, const u8 *buf,
+				     int len)
+{
+	int i;
+	struct nand_chip *chip = mtd_to_nand(mtd);
+
+	if (IS_ALIGNED((uint32_t)buf, sizeof(uint32_t)) &&
+	    IS_ALIGNED(len, sizeof(uint32_t))) {
+		u32 *ptr = (u32 *)buf;
+
+		len /= 4;
+		for (i = 0; i < len; i++)
+			writel(ptr[i], chip->IO_ADDR_W);
+	} else {
+		for (i = 0; i < len; i++)
+			writeb(buf[i], chip->IO_ADDR_W);
+	}
+}
+
+/**
+ * pl353_nand_calculate_hwecc - Calculate Hardware ECC
+ * @mtd:	Pointer to the mtd_info structure
+ * @data:	Pointer to the page data
+ * @ecc:	Pointer to the ECC buffer where ECC data needs to be stored
+ *
+ * This function retrieves the Hardware ECC data from the controller and returns
+ * ECC data back to the MTD subsystem.
+ *
+ * Return:	0 on success or error value on failure
+ */
+static int pl353_nand_calculate_hwecc(struct mtd_info *mtd,
+				      const u8 *data, u8 *ecc)
+{
+	u32 ecc_value;
+	u8 ecc_reg, ecc_byte, ecc_status;
+	unsigned long timeout = jiffies + PL353_NAND_ECC_BUSY_TIMEOUT;
+	/* Wait till the ECC operation is complete or timeout */
+	do {
+		if (pl353_smc_ecc_is_busy())
+			cpu_relax();
+		else
+			break;
+	} while (!time_after_eq(jiffies, timeout));
+
+	if (time_after_eq(jiffies, timeout)) {
+		pr_err("%s timed out\n", __func__);
+		return -ETIMEDOUT;
+	}
+
+	for (ecc_reg = 0; ecc_reg < 4; ecc_reg++) {
+		/* Read ECC value for each block */
+		ecc_value = pl353_smc_get_ecc_val(ecc_reg);
+		ecc_status = (ecc_value >> PL353_NAND_ECC_VALID_SHIFT);
+		/* ECC value valid */
+		if (ecc_status & PL353_NAND_ECC_VALID_MASK) {
+			for (ecc_byte = 0; ecc_byte < 3; ecc_byte++) {
+				/* Copy ECC bytes to MTD buffer */
+				*ecc = ~ecc_value & 0xFF;
+				ecc_value = ecc_value >> 8;
+				ecc++;
+			}
+		} else {
+			pr_warn("%s status failed\n", __func__);
+			return -1;
+		}
+	}
+	return 0;
+}
+
+/**
+ * onehot - onehot function
+ * @value:	Value to check for onehot
+ *
+ * This function checks whether a value is onehot or not.
+ * onehot is if and only if onebit is set.
+ *
+ * Return:	1 if it is onehot else 0
+ */
+static bool onehot(unsigned short value)
+{
+	return (value & (value - 1)) == 0;
+}
+
+/**
+ * pl353_nand_correct_data - ECC correction function
+ * @mtd:	Pointer to the mtd_info structure
+ * @buf:	Pointer to the page data
+ * @read_ecc:	Pointer to the ECC value read from spare data area
+ * @calc_ecc:	Pointer to the calculated ECC value
+ *
+ * This function corrects the ECC single bit errors & detects 2-bit errors.
+ *
+ * Return:	0 if no ECC errors found
+ *		1 if single bit error found and corrected.
+ *		-1 if multiple uncorrectable ECC errors found.
+ */
+static int pl353_nand_correct_data(struct mtd_info *mtd, unsigned char *buf,
+				   unsigned char *read_ecc,
+				   unsigned char *calc_ecc)
+{
+	unsigned char bit_addr;
+	unsigned int byte_addr;
+	unsigned short ecc_odd, ecc_even, read_ecc_lower, read_ecc_upper;
+	unsigned short calc_ecc_lower, calc_ecc_upper;
+
+	read_ecc_lower = (read_ecc[0] | (read_ecc[1] << 8)) & 0xfff;
+	read_ecc_upper = ((read_ecc[1] >> 4) | (read_ecc[2] << 4)) & 0xfff;
+
+	calc_ecc_lower = (calc_ecc[0] | (calc_ecc[1] << 8)) & 0xfff;
+	calc_ecc_upper = ((calc_ecc[1] >> 4) | (calc_ecc[2] << 4)) & 0xfff;
+
+	ecc_odd = read_ecc_lower ^ calc_ecc_lower;
+	ecc_even = read_ecc_upper ^ calc_ecc_upper;
+
+	/* no error */
+	if (!ecc_odd && !ecc_even)
+		return 0;
+
+	if (ecc_odd == (~ecc_even & 0xfff)) {
+		/* bits [11:3] of error code is byte offset */
+		byte_addr = (ecc_odd >> 3) & 0x1ff;
+		/* bits [2:0] of error code is bit offset */
+		bit_addr = ecc_odd & 0x7;
+		/* Toggling error bit */
+		buf[byte_addr] ^= (BIT(bit_addr));
+		return 1;
+	}
+	/* one error in parity */
+	if (onehot(ecc_odd | ecc_even) == 1)
+		return 1;
+
+	/* Uncorrectable error */
+	return -1;
+}
+
+static int pl353_dev_timeout(struct mtd_info *mtd, struct nand_chip *chip,
+			     unsigned long timeout)
+{
+	if (timeout)
+		timeout = jiffies + msecs_to_jiffies(timeout);
+	else
+		timeout = jiffies + PL353_NAND_DEV_BUSY_TIMEOUT;
+
+	do {
+		if (chip->dev_ready(mtd))
+			break;
+		cpu_relax();
+	} while (!time_after_eq(jiffies, timeout));
+
+	if (time_after_eq(jiffies, timeout)) {
+		pr_err("%s timed out\n", __func__);
+		return -1;
+	}
+
+	return 0;
+}
+
+static void pl353_prepare_cmd(struct mtd_info *mtd, struct nand_chip *chip,
+			      int page, int column, int start_cmd, int end_cmd,
+			      bool read)
+{
+	unsigned long data_phase_addr;
+	u32 end_cmd_valid = 0;
+	void __iomem *cmd_addr;
+	unsigned long cmd_phase_addr = 0, cmd_data = 0;
+
+	struct pl353_nand_info *xnfc =
+		container_of(chip, struct pl353_nand_info, chip);
+
+	end_cmd_valid = read ? 1 : 0;
+
+	cmd_phase_addr = (unsigned long __force)xnfc->nand_base +
+			 ((xnfc->addr_cycles
+			 << ADDR_CYCLES_SHIFT) |
+			 (end_cmd_valid << END_CMD_VALID_SHIFT) |
+			 (COMMAND_PHASE) |
+			 (end_cmd << END_CMD_SHIFT) |
+			 (start_cmd << START_CMD_SHIFT));
+	cmd_addr = (void __iomem * __force)cmd_phase_addr;
+
+	/* Get the data phase address */
+	data_phase_addr = (unsigned long __force)xnfc->nand_base +
+			  ((0x0 << CLEAR_CS_SHIFT) |
+			  (0 << END_CMD_VALID_SHIFT) |
+			  (DATA_PHASE) |
+			  (end_cmd << END_CMD_SHIFT) |
+			  (0x0 << ECC_LAST_SHIFT));
+
+	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
+	chip->IO_ADDR_W = chip->IO_ADDR_R;
+	if (chip->options & NAND_BUSWIDTH_16)
+		column /= 2;
+	cmd_data = column;
+	if (mtd->writesize > PL353_NAND_ECC_SIZE) {
+		cmd_data |= page << 16;
+		/* Another address cycle for devices > 128MiB */
+		if (chip->options & NAND_ROW_ADDR_3) {
+			writel_relaxed(cmd_data, cmd_addr);
+			cmd_data = (page >> 16);
+		}
+	} else {
+		cmd_data |= page << 8;
+	}
+
+	writel_relaxed(cmd_data, cmd_addr);
+}
+
+/**
+ * pl353_nand_read_oob - [REPLACEABLE] the most common OOB data read function
+ * @mtd:	Pointer to the mtd info structure
+ * @chip:	Pointer to the NAND chip info structure
+ * @page:	Page number to read
+ *
+ * Return:	Always return zero
+ */
+static int pl353_nand_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
+			       int page)
+{
+	unsigned long data_phase_addr;
+	u8 *p;
+	struct pl353_nand_info *xnfc =
+		container_of(chip, struct pl353_nand_info, chip);
+	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
+
+	chip->pagebuf = -1;
+	if (mtd->writesize < PL353_NAND_ECC_SIZE)
+		return 0;
+
+	pl353_prepare_cmd(mtd, chip, page, mtd->writesize, NAND_CMD_READ0,
+			  NAND_CMD_READSTART, 1);
+
+	ndelay(100);
+	pl353_dev_timeout(mtd, chip, 0);
+
+	p = chip->oob_poi;
+	pl353_nand_read_data_op(chip, p,
+				(mtd->oobsize -
+				PL353_NAND_LAST_TRANSFER_LENGTH));
+	p += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
+	data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
+	data_phase_addr -= nand_offset;
+	data_phase_addr |= PL353_NAND_CLEAR_CS;
+	data_phase_addr += nand_offset;
+	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
+	pl353_nand_read_data_op(chip, p, PL353_NAND_LAST_TRANSFER_LENGTH);
+
+	return 0;
+}
+
+/**
+ * pl353_nand_write_oob - [REPLACEABLE] the most common OOB data write function
+ * @mtd:	Pointer to the mtd info structure
+ * @chip:	Pointer to the NAND chip info structure
+ * @page:	Page number to write
+ *
+ * Return:	Zero on success and EIO on failure
+ */
+static int pl353_nand_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
+				int page)
+{
+	const u8 *buf = chip->oob_poi;
+	unsigned long data_phase_addr;
+	struct pl353_nand_info *xnfc =
+		container_of(chip, struct pl353_nand_info, chip);
+	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
+	u32 addrcycles = 0;
+
+	chip->pagebuf = -1;
+	addrcycles = xnfc->addr_cycles;
+	pl353_prepare_cmd(mtd, chip, page, mtd->writesize, NAND_CMD_SEQIN,
+			  NAND_CMD_PAGEPROG, 0);
+	ndelay(100);
+	pl353_nand_write_data_op(mtd, buf,
+				 (mtd->oobsize -
+				 PL353_NAND_LAST_TRANSFER_LENGTH));
+	buf += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
+
+	data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
+	data_phase_addr -= nand_offset;
+	data_phase_addr |= PL353_NAND_CLEAR_CS;
+	data_phase_addr |= (1 << END_CMD_VALID_SHIFT);
+	data_phase_addr += nand_offset;
+	chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
+	pl353_nand_write_data_op(mtd, buf, PL353_NAND_LAST_TRANSFER_LENGTH);
+	nand_wait_ready(mtd);
+
+	return 0;
+}
+
+/**
+ * pl353_nand_read_page_raw - [Intern] read raw page data without ecc
+ * @mtd:		Pointer to the mtd info structure
+ * @chip:		Pointer to the NAND chip info structure
+ * @buf:		Pointer to the data buffer
+ * @oob_required:	Caller requires OOB data read to chip->oob_poi
+ * @page:		Page number to read
+ *
+ * Return:	Always return zero
+ */
+static int pl353_nand_read_page_raw(struct mtd_info *mtd,
+				    struct nand_chip *chip,
+				    u8 *buf, int oob_required, int page)
+{
+	unsigned long data_phase_addr;
+	u8 *p;
+	struct pl353_nand_info *xnfc =
+		container_of(chip, struct pl353_nand_info, chip);
+	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
+
+	pl353_nand_read_data_op(chip, buf, mtd->writesize);
+	p = chip->oob_poi;
+	pl353_nand_read_data_op(chip, p,
+				(mtd->oobsize -
+				PL353_NAND_LAST_TRANSFER_LENGTH));
+	p += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
+
+	data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
+	data_phase_addr -= nand_offset;
+	data_phase_addr |= PL353_NAND_CLEAR_CS;
+	data_phase_addr += nand_offset;
+	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
+
+	pl353_nand_read_data_op(chip, p, PL353_NAND_LAST_TRANSFER_LENGTH);
+
+	return 0;
+}
+
+/**
+ * pl353_nand_write_page_raw - [Intern] raw page write function
+ * @mtd:		Pointer to the mtd info structure
+ * @chip:		Pointer to the NAND chip info structure
+ * @buf:		Pointer to the data buffer
+ * @oob_required:	Caller requires OOB data read to chip->oob_poi
+ * @page:		Page number to write
+ *
+ * Return:	Always return zero
+ */
+static int pl353_nand_write_page_raw(struct mtd_info *mtd,
+				     struct nand_chip *chip,
+				     const u8 *buf, int oob_required,
+				     int page)
+{
+	unsigned long data_phase_addr;
+	u8 *p;
+
+	struct pl353_nand_info *xnfc =
+		container_of(chip, struct pl353_nand_info, chip);
+	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
+
+	pl353_nand_write_data_op(mtd, buf, mtd->writesize);
+	p = chip->oob_poi;
+	pl353_nand_write_data_op(mtd, p,
+				 (mtd->oobsize -
+				 PL353_NAND_LAST_TRANSFER_LENGTH));
+	p += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
+
+	data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
+	data_phase_addr -= nand_offset;
+	data_phase_addr |= PL353_NAND_CLEAR_CS;
+	data_phase_addr |= (1 << END_CMD_VALID_SHIFT);
+	data_phase_addr += nand_offset;
+	chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
+
+	pl353_nand_write_data_op(mtd, p, PL353_NAND_LAST_TRANSFER_LENGTH);
+
+	return 0;
+}
+
+/**
+ * nand_write_page_hwecc - Hardware ECC based page write function
+ * @mtd:		Pointer to the mtd info structure
+ * @chip:		Pointer to the NAND chip info structure
+ * @buf:		Pointer to the data buffer
+ * @oob_required:	Caller requires OOB data read to chip->oob_poi
+ * @page:		Page number to write
+ *
+ * This functions writes data and hardware generated ECC values in to the page.
+ *
+ * Return:	Always return zero
+ */
+static int pl353_nand_write_page_hwecc(struct mtd_info *mtd,
+				       struct nand_chip *chip,
+				       const u8 *buf, int oob_required,
+				       int page)
+{
+	int eccsize = chip->ecc.size;
+	int eccsteps = chip->ecc.steps;
+	u8 *ecc_calc = chip->ecc.calc_buf;
+	u8 *oob_ptr;
+	const u8 *p = buf;
+	u32 ret;
+	unsigned long data_phase_addr;
+	struct pl353_nand_info *xnfc =
+		container_of(chip, struct pl353_nand_info, chip);
+	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
+
+	pl353_prepare_cmd(mtd, chip, page, 0, NAND_CMD_SEQIN,
+			  NAND_CMD_PAGEPROG, 0);
+	ndelay(100);
+	for ( ; (eccsteps - 1); eccsteps--) {
+		pl353_nand_write_data_op(mtd, p, eccsize);
+		p += eccsize;
+	}
+	pl353_nand_write_data_op(mtd, p,
+				 (eccsize - PL353_NAND_LAST_TRANSFER_LENGTH));
+	p += (eccsize - PL353_NAND_LAST_TRANSFER_LENGTH);
+
+	/* Set ECC Last bit to 1 */
+	data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
+	data_phase_addr -= nand_offset;
+	data_phase_addr |= PL353_NAND_ECC_LAST;
+	data_phase_addr += nand_offset;
+	chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
+	pl353_nand_write_data_op(mtd, p, PL353_NAND_LAST_TRANSFER_LENGTH);
+
+	p = buf;
+	chip->ecc.calculate(mtd, p, &ecc_calc[0]);
+
+	/* Wait for ECC to be calculated and read the error values */
+	ret = mtd_ooblayout_set_eccbytes(mtd, ecc_calc, chip->oob_poi,
+					 0, chip->ecc.total);
+	if (ret)
+		return ret;
+	/* Clear ECC last bit */
+	data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
+	data_phase_addr -= nand_offset;
+	data_phase_addr &= ~PL353_NAND_ECC_LAST;
+	data_phase_addr += nand_offset;
+	chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
+
+	/* Write the spare area with ECC bytes */
+	oob_ptr = chip->oob_poi;
+	pl353_nand_write_data_op(mtd, oob_ptr,
+				 (mtd->oobsize -
+				 PL353_NAND_LAST_TRANSFER_LENGTH));
+
+	data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
+	data_phase_addr -= nand_offset;
+	data_phase_addr |= PL353_NAND_CLEAR_CS;
+	data_phase_addr |= (1 << END_CMD_VALID_SHIFT);
+	data_phase_addr += nand_offset;
+	chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
+	oob_ptr += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
+	pl353_nand_write_data_op(mtd, oob_ptr, PL353_NAND_LAST_TRANSFER_LENGTH);
+
+	/*
+	 * Apply this short delay always to ensure that we do wait tWB in any
+	 * case on any machine.
+	 */
+	ndelay(100);
+	nand_wait_ready(mtd);
+
+	return 0;
+}
+
+/**
+ * pl353_nand_read_page_hwecc - Hardware ECC based page read function
+ * @mtd:		Pointer to the mtd info structure
+ * @chip:		Pointer to the NAND chip info structure
+ * @buf:		Pointer to the buffer to store read data
+ * @oob_required:	Caller requires OOB data read to chip->oob_poi
+ * @page:		Page number to read
+ *
+ * This functions reads data and checks the data integrity by comparing hardware
+ * generated ECC values and read ECC values from spare area.
+ *
+ * Return:	0 always and updates ECC operation status in to MTD structure
+ */
+static int pl353_nand_read_page_hwecc(struct mtd_info *mtd,
+				      struct nand_chip *chip,
+				      u8 *buf, int oob_required, int page)
+{
+	int i, stat, eccsize = chip->ecc.size;
+	int eccbytes = chip->ecc.bytes;
+	int eccsteps = chip->ecc.steps;
+	u8 *p = buf;
+	u8 *ecc_calc = chip->ecc.calc_buf;
+	u8 *ecc = chip->ecc.code_buf;
+	unsigned int max_bitflips = 0;
+	u8 *oob_ptr;
+	u32 ret;
+	unsigned long data_phase_addr;
+	struct pl353_nand_info *xnfc =
+		container_of(chip, struct pl353_nand_info, chip);
+	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
+
+	pl353_prepare_cmd(mtd, chip, page, 0, NAND_CMD_READ0,
+			  NAND_CMD_READSTART, 1);
+	ndelay(100);
+	pl353_dev_timeout(mtd, chip, 0);
+
+	for ( ; (eccsteps - 1); eccsteps--) {
+		pl353_nand_read_data_op(chip, p, eccsize);
+		p += eccsize;
+	}
+	pl353_nand_read_data_op(chip, p,
+				(eccsize - PL353_NAND_LAST_TRANSFER_LENGTH));
+	p += (eccsize - PL353_NAND_LAST_TRANSFER_LENGTH);
+
+	/* Set ECC Last bit to 1 */
+	data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
+	data_phase_addr -= nand_offset;
+	data_phase_addr |= PL353_NAND_ECC_LAST;
+	data_phase_addr += nand_offset;
+	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
+	pl353_nand_read_data_op(chip, p, PL353_NAND_LAST_TRANSFER_LENGTH);
+
+	/* Read the calculated ECC value */
+	p = buf;
+	chip->ecc.calculate(mtd, p, &ecc_calc[0]);
+
+	/* Clear ECC last bit */
+	data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
+	data_phase_addr -= nand_offset;
+	data_phase_addr &= ~PL353_NAND_ECC_LAST;
+	data_phase_addr += nand_offset;
+	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
+
+	/* Read the stored ECC value */
+	oob_ptr = chip->oob_poi;
+	pl353_nand_read_data_op(chip, oob_ptr,
+				(mtd->oobsize -
+				PL353_NAND_LAST_TRANSFER_LENGTH));
+
+	/* de-assert chip select */
+	data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
+	data_phase_addr -= nand_offset;
+	data_phase_addr |= PL353_NAND_CLEAR_CS;
+	data_phase_addr += nand_offset;
+	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
+
+	oob_ptr += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
+	pl353_nand_read_data_op(chip, oob_ptr, PL353_NAND_LAST_TRANSFER_LENGTH);
+
+	ret = mtd_ooblayout_get_eccbytes(mtd, ecc, chip->oob_poi, 0,
+					 chip->ecc.total);
+	if (ret)
+		return ret;
+
+	eccsteps = chip->ecc.steps;
+	p = buf;
+
+	/* Check ECC error for all blocks and correct if it is correctable */
+	for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
+		stat = chip->ecc.correct(mtd, p, &ecc[i], &ecc_calc[i]);
+		if (stat < 0) {
+			mtd->ecc_stats.failed++;
+		} else {
+			mtd->ecc_stats.corrected += stat;
+			max_bitflips = max_t(unsigned int, max_bitflips, stat);
+		}
+	}
+
+	return max_bitflips;
+}
+
+/**
+ * pl353_nand_select_chip - Select the flash device
+ * @mtd:	Pointer to the mtd info structure
+ * @chip:	Pointer to the NAND chip info structure
+ *
+ * This function is empty as the NAND controller handles chip select line
+ * internally based on the chip address passed in command and data phase.
+ */
+static void pl353_nand_select_chip(struct mtd_info *mtd, int chip)
+{
+}
+
+/* NAND framework ->exec_op() hooks and related helpers */
+static void pl353_nfc_parse_instructions(struct nand_chip *chip,
+					 const struct nand_subop *subop,
+					 struct pl353_nfc_op *nfc_op)
+{
+	const struct nand_op_instr *instr = NULL;
+	unsigned int op_id, offset, naddrs;
+	int i, len;
+	const u8 *addrs;
+
+	memset(nfc_op, 0, sizeof(struct pl353_nfc_op));
+	for (op_id = 0; op_id < subop->ninstrs; op_id++) {
+		nfc_op->len = nand_subop_get_data_len(subop, op_id);
+		len = nand_subop_get_data_len(subop, op_id);
+		instr = &subop->instrs[op_id];
+		//if (subop->ninstrs == 1)
+			//nfc_op->cmnds[0] = -1;
+		switch (instr->type) {
+		case NAND_OP_CMD_INSTR:
+			nfc_op->type = NAND_OP_CMD_INSTR;
+			if (op_id)
+				nfc_op->cmnds[1] = instr->ctx.cmd.opcode;
+			else
+				nfc_op->cmnds[0] = instr->ctx.cmd.opcode;
+			nfc_op->cle_ale_delay_ns = instr->delay_ns;
+			break;
+
+		case NAND_OP_ADDR_INSTR:
+			offset = nand_subop_get_addr_start_off(subop, op_id);
+			naddrs = nand_subop_get_num_addr_cyc(subop, op_id);
+			addrs = &instr->ctx.addr.addrs[offset];
+			nfc_op->addrs = instr->ctx.addr.addrs[offset];
+			for (i = 0; i < min_t(unsigned int, 4, naddrs); i++) {
+				nfc_op->addrs |= instr->ctx.addr.addrs[i] <<
+						 (8 * i);
+			}
+
+			if (naddrs >= 5)
+				nfc_op->addr5 = addrs[4];
+			if (naddrs >= 6)
+				nfc_op->addr6 = addrs[5];
+			nfc_op->naddrs = nand_subop_get_num_addr_cyc(subop,
+								     op_id);
+			nfc_op->cle_ale_delay_ns = instr->delay_ns;
+			break;
+
+		case NAND_OP_DATA_IN_INSTR:
+			nfc_op->data_instr = instr;
+			nfc_op->type = NAND_OP_DATA_IN_INSTR;
+			nfc_op->data_instr_idx = op_id;
+			nfc_op->data_delay_ns = instr->delay_ns;
+			break;
+
+		case NAND_OP_DATA_OUT_INSTR:
+			nfc_op->data_instr = instr;
+			nfc_op->type = NAND_OP_DATA_IN_INSTR;
+			nfc_op->data_instr_idx = op_id;
+			nfc_op->data_delay_ns = instr->delay_ns;
+			break;
+
+		case NAND_OP_WAITRDY_INSTR:
+			nfc_op->rdy_timeout_ms = instr->ctx.waitrdy.timeout_ms;
+			nfc_op->rdy_delay_ns = instr->delay_ns;
+			nfc_op->wait = true;
+			break;
+		}
+	}
+}
+
+static void cond_delay(unsigned int ns)
+{
+	if (!ns)
+		return;
+
+	if (ns < 10000)
+		ndelay(ns);
+	else
+		udelay(DIV_ROUND_UP(ns, 1000));
+}
+
+/**
+ * pl353_nand_cmd_function - Send command to NAND device
+ * @chip:	Pointer to the NAND chip info structure
+ * @subop:	Pointer to array of instructions
+ * Return:	Always return zero
+ */
+static int pl353_nand_cmd_function(struct nand_chip *chip,
+				   const struct nand_subop *subop)
+{
+	struct mtd_info *mtd = nand_to_mtd(chip);
+	const struct nand_op_instr *instr;
+	struct pl353_nfc_op nfc_op = {};
+	struct pl353_nand_info *xnfc =
+		container_of(chip, struct pl353_nand_info, chip);
+	void __iomem *cmd_addr;
+	unsigned long cmd_data = 0, end_cmd_valid = 0;
+	unsigned long cmd_phase_addr, data_phase_addr, end_cmd;
+	unsigned int op_id, len, offset;
+	bool reading;
+
+	pl353_nfc_parse_instructions(chip, subop, &nfc_op);
+	instr = nfc_op.data_instr;
+	op_id = nfc_op.data_instr_idx;
+	len = nand_subop_get_data_len(subop, op_id);
+	offset = nand_subop_get_data_start_off(subop, op_id);
+
+	pl353_smc_clr_nand_int();
+	/* Get the command phase address */
+	if (nfc_op.cmnds[1] != 0) {
+		if (nfc_op.cmnds[0] == NAND_CMD_SEQIN)
+			end_cmd_valid = 0;
+		else
+			end_cmd_valid = 1;
+		end_cmd = nfc_op.cmnds[1];
+	}  else {
+		end_cmd = 0x0;
+	}
+	cmd_phase_addr = (unsigned long __force)xnfc->nand_base +
+			 ((nfc_op.naddrs << ADDR_CYCLES_SHIFT) |
+			 (end_cmd_valid << END_CMD_VALID_SHIFT) |
+			 (COMMAND_PHASE) |
+			 (end_cmd << END_CMD_SHIFT) |
+			 (nfc_op.cmnds[0] << START_CMD_SHIFT));
+
+	cmd_addr = (void __iomem * __force)cmd_phase_addr;
+	/* Get the data phase address */
+	end_cmd_valid = 0;
+
+	data_phase_addr = (unsigned long __force)xnfc->nand_base +
+			  ((0x0 << CLEAR_CS_SHIFT) |
+			  (end_cmd_valid << END_CMD_VALID_SHIFT) |
+			  (DATA_PHASE) |
+			  (end_cmd << END_CMD_SHIFT) |
+			  (0x0 << ECC_LAST_SHIFT));
+	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
+	chip->IO_ADDR_W = chip->IO_ADDR_R;
+	/* Command phase AXI Read & Write */
+	if (nfc_op.naddrs >= 5) {
+		if (mtd->writesize > PL353_NAND_ECC_SIZE) {
+			cmd_data = nfc_op.addrs;
+			/* Another address cycle for devices > 128MiB */
+			if (chip->options & NAND_ROW_ADDR_3) {
+				writel_relaxed(cmd_data, cmd_addr);
+				cmd_data = nfc_op.addr5;
+				if (nfc_op.naddrs >= 6)
+					cmd_data |= (nfc_op.addr6 << 8);
+			}
+		}
+	}  else {
+		if (nfc_op.addrs != -1) {
+			int column = nfc_op.addrs;
+			/*
+			 * Change read/write column, read id etc
+			 * Adjust columns for 16 bit bus width
+			 */
+			if ((chip->options & NAND_BUSWIDTH_16) &&
+			    (nfc_op.cmnds[0] == NAND_CMD_READ0 ||
+				nfc_op.cmnds[0] == NAND_CMD_SEQIN ||
+				nfc_op.cmnds[0] == NAND_CMD_RNDOUT ||
+				nfc_op.cmnds[0] == NAND_CMD_RNDIN)) {
+				column >>= 1;
+			}
+			cmd_data = column;
+		}
+	}
+	writel_relaxed(cmd_data, cmd_addr);
+	ndelay(100);
+
+	cond_delay(nfc_op.cle_ale_delay_ns);
+	if (!nfc_op.data_instr) {
+		msleep(nfc_op.rdy_timeout_ms);
+		cond_delay(nfc_op.rdy_delay_ns);
+		return 0;
+	}
+
+	reading = (nfc_op.data_instr->type == NAND_OP_DATA_IN_INSTR);
+
+	if (!reading) {
+		if (nfc_op.cmnds[0] == NAND_CMD_SEQIN &&
+		    nfc_op.cmnds[1] == NAND_CMD_PAGEPROG) {
+			pl353_nand_write_page_raw(mtd, chip,
+						  instr->ctx.data.buf.out, 0,
+						  nfc_op.addrs);
+		} else {
+			pl353_nand_write_data_op(mtd, instr->ctx.data.buf.out,
+						 len);
+		}
+		if (nfc_op.rdy_timeout_ms)
+			pl353_dev_timeout(mtd, chip, nfc_op.rdy_timeout_ms);
+		cond_delay(nfc_op.rdy_delay_ns);
+
+	}
+
+	else if (reading) {
+		if (nfc_op.rdy_timeout_ms)
+			pl353_dev_timeout(mtd, chip, nfc_op.rdy_timeout_ms);
+		cond_delay(nfc_op.rdy_delay_ns);
+		pl353_nand_read_data_op(chip, instr->ctx.data.buf.in, len);
+	}
+
+	return 0;
+}
+
+static const struct nand_op_parser pl353_nfc_op_parser = NAND_OP_PARSER
+	(NAND_OP_PARSER_PATTERN
+		(pl353_nand_cmd_function,
+		NAND_OP_PARSER_PAT_CMD_ELEM(true),
+		NAND_OP_PARSER_PAT_ADDR_ELEM(true, 7),
+		NAND_OP_PARSER_PAT_WAITRDY_ELEM(true),
+		NAND_OP_PARSER_PAT_DATA_IN_ELEM(false, 2048)),
+	NAND_OP_PARSER_PATTERN
+		(pl353_nand_cmd_function,
+		NAND_OP_PARSER_PAT_CMD_ELEM(false),
+		NAND_OP_PARSER_PAT_ADDR_ELEM(false, 7),
+		NAND_OP_PARSER_PAT_CMD_ELEM(false),
+		NAND_OP_PARSER_PAT_WAITRDY_ELEM(false),
+		NAND_OP_PARSER_PAT_DATA_IN_ELEM(false, 2048)),
+	NAND_OP_PARSER_PATTERN
+		(pl353_nand_cmd_function,
+		NAND_OP_PARSER_PAT_CMD_ELEM(false),
+		NAND_OP_PARSER_PAT_ADDR_ELEM(true, 7),
+		NAND_OP_PARSER_PAT_CMD_ELEM(true),
+		NAND_OP_PARSER_PAT_WAITRDY_ELEM(false)),
+	NAND_OP_PARSER_PATTERN
+		(pl353_nand_cmd_function,
+		NAND_OP_PARSER_PAT_CMD_ELEM(false),
+		NAND_OP_PARSER_PAT_ADDR_ELEM(false, 8),
+		NAND_OP_PARSER_PAT_DATA_OUT_ELEM(false, 2048),
+		NAND_OP_PARSER_PAT_CMD_ELEM(true),
+		NAND_OP_PARSER_PAT_WAITRDY_ELEM(true)),
+	NAND_OP_PARSER_PATTERN
+		(pl353_nand_cmd_function,
+		NAND_OP_PARSER_PAT_CMD_ELEM(false)),
+	);
+
+static int pl353_nfc_exec_op(struct nand_chip *chip,
+			     const struct nand_operation *op,
+			     bool check_only)
+{
+	return nand_op_parser_exec_op(chip, &pl353_nfc_op_parser,
+					      op, check_only);
+}
+
+/**
+ * pl353_nand_device_ready - Check device ready/busy line
+ * @mtd:	Pointer to the mtd_info structure
+ *
+ * Return:	0 on busy or 1 on ready state
+ */
+static int pl353_nand_device_ready(struct mtd_info *mtd)
+{
+	if (pl353_smc_get_nand_int_status_raw()) {
+		pl353_smc_clr_nand_int();
+		return 1;
+	}
+
+	return 0;
+}
+
+/**
+ * pl353_nand_ecc_init - Initialize the ecc information as per the ecc mode
+ * @mtd:	Pointer to the mtd_info structure
+ * @ecc:	Pointer to ECC control structure
+ * @ecc_mode:	ondie ecc status
+ *
+ * This function initializes the ecc block and functional pointers as per the
+ * ecc mode
+ */
+static int pl353_nand_ecc_init(struct mtd_info *mtd, struct nand_ecc_ctrl *ecc,
+				int ecc_mode)
+{
+	struct nand_chip *chip = mtd_to_nand(mtd);
+	struct pl353_nand_info *xnfc =
+		container_of(chip, struct pl353_nand_info, chip);
+	u32 err = 0;
+
+	if (ecc_mode == NAND_ECC_ON_DIE) {
+		pl353_smc_set_ecc_mode(PL353_SMC_ECCMODE_BYPASS);
+		/*
+		 * On-Die ECC spare bytes offset 8 is used for ECC codes
+		 * Use the BBT pattern descriptors
+		 */
+		chip->bbt_td = &bbt_main_descr;
+		chip->bbt_md = &bbt_mirror_descr;
+		bitmap_set(chip->parameters.get_feature_list,
+			   ONFI_FEATURE_ON_DIE_ECC, ONFI_FEATURE_ON_DIE_ECC_EN);
+		bitmap_set(chip->parameters.set_feature_list,
+			   ONFI_FEATURE_ON_DIE_ECC, ONFI_FEATURE_ON_DIE_ECC_EN);
+	} else {
+		ecc->read_oob = pl353_nand_read_oob;
+		ecc->write_oob = pl353_nand_write_oob;
+
+		ecc->mode = NAND_ECC_HW;
+		/* Hardware ECC generates 3 bytes ECC code for each 512 bytes */
+		ecc->bytes = 3;
+		ecc->strength = 1;
+		ecc->calculate = pl353_nand_calculate_hwecc;
+		ecc->correct = pl353_nand_correct_data;
+		ecc->read_page = pl353_nand_read_page_hwecc;
+		ecc->size = PL353_NAND_ECC_SIZE;
+		ecc->write_page = pl353_nand_write_page_hwecc;
+		pl353_smc_set_ecc_pg_size(mtd->writesize);
+		switch (mtd->writesize) {
+		case SZ_512:
+		case SZ_1K:
+		case SZ_2K:
+			pl353_smc_set_ecc_mode(PL353_SMC_ECCMODE_APB);
+			break;
+		default:
+			/*
+			 * The software ECC routines won't work with the
+			 * SMC controller
+			 */
+			ecc->calculate = nand_calculate_ecc;
+			ecc->correct = nand_correct_data;
+			ecc->size = 256;
+			break;
+		}
+		if (mtd->writesize <= SZ_512)
+			xnfc->addr_cycles = 1;
+		else
+			xnfc->addr_cycles = 2;
+
+		if (chip->options & NAND_ROW_ADDR_3)
+			xnfc->addr_cycles += 3;
+		else
+			xnfc->addr_cycles += 2;
+
+		if (mtd->oobsize == 16) {
+			mtd_set_ooblayout(mtd, &pl353_ecc_ooblayout16_ops);
+		} else if (mtd->oobsize == 64) {
+			mtd_set_ooblayout(mtd, &pl353_ecc_ooblayout64_ops);
+		} else {
+			err = ENXIO;
+			dev_err(xnfc->dev, "Unsupported oob Layout\n");
+		}
+	}
+	return err;
+}
+static int pl353_setup_data_interface(struct mtd_info *mtd, int csline,
+				       const struct nand_data_interface *conf)
+{
+	struct nand_chip *chip = mtd_to_nand(mtd);
+	struct pl353_nand_info *xnfc =
+		container_of(chip, struct pl353_nand_info, chip);
+	const struct nand_sdr_timings *sdr;
+	u32 timigs[7], mckperiodps;
+
+	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
+		return -EINVAL;
+
+	sdr = nand_get_sdr_timings(conf);
+	if (IS_ERR(sdr))
+		return PTR_ERR(sdr);
+	/*
+	 * SDR timings are given in pico-seconds while NFC timings must be
+	 * expressed in NAND controller clock cycles.
+	 */
+	mckperiodps = NSEC_PER_SEC / clk_get_rate(xnfc->mclk);
+	mckperiodps *= 1000;
+	timigs[0] = DIV_ROUND_UP(sdr->tRC_min, mckperiodps);
+	timigs[1] = DIV_ROUND_UP(sdr->tWC_min, mckperiodps);
+	timigs[2] = DIV_ROUND_UP(sdr->tREA_max, mckperiodps);
+	timigs[3] = DIV_ROUND_UP(sdr->tWP_min, mckperiodps);
+	timigs[4] = DIV_ROUND_UP(sdr->tCLR_min, mckperiodps);
+	timigs[5] = DIV_ROUND_UP(sdr->tAR_min, mckperiodps);
+	timigs[6] = DIV_ROUND_UP(sdr->tRR_min, mckperiodps);
+	pl353_smc_set_cycles(timigs[0], timigs[1], timigs[2], timigs[3],
+			     timigs[4], timigs[5], timigs[6]);
+
+	return 0;
+}
+/**
+ * pl353_nand_probe - Probe method for the NAND driver
+ * @pdev:	Pointer to the platform_device structure
+ *
+ * This function initializes the driver data structures and the hardware.
+ *
+ * Return:	0 on success or error value on failure
+ */
+static int pl353_nand_probe(struct platform_device *pdev)
+{
+	struct pl353_nand_info *xnfc;
+	struct mtd_info *mtd;
+	struct nand_chip *chip;
+	struct resource *res;
+	struct device_node *np;
+	u32 ret;
+
+	xnfc = devm_kzalloc(&pdev->dev, sizeof(*xnfc), GFP_KERNEL);
+	if (!xnfc)
+		return -ENOMEM;
+	xnfc->dev = &pdev->dev;
+	/* Map physical address of NAND flash */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	xnfc->nand_base = devm_ioremap_resource(xnfc->dev, res);
+	if (IS_ERR(xnfc->nand_base))
+		return PTR_ERR(xnfc->nand_base);
+
+	chip = &xnfc->chip;
+	mtd = nand_to_mtd(chip);
+	chip->exec_op = pl353_nfc_exec_op;
+	nand_set_controller_data(chip, xnfc);
+	mtd->priv = chip;
+	mtd->owner = THIS_MODULE;
+	if (!mtd->name) {
+		/*
+		 * If the new bindings are used and the bootloader has not been
+		 * updated to pass a new mtdparts parameter on the cmdline, you
+		 * should define the following property in your NAND node, ie:
+		 *
+		 *	label = "pl353-nand";
+		 *
+		 * This way, mtd->name will be set by the core when
+		 * nand_set_flash_node() is called.
+		 */
+		mtd->name = devm_kasprintf(xnfc->dev, GFP_KERNEL,
+					   "%s", PL353_NAND_DRIVER_NAME);
+		if (!mtd->name) {
+			dev_err(xnfc->dev, "Failed to allocate mtd->name\n");
+			return -ENOMEM;
+		}
+	}
+	nand_set_flash_node(chip, xnfc->dev->of_node);
+
+	/* Set address of NAND IO lines */
+	chip->IO_ADDR_R = xnfc->nand_base;
+	chip->IO_ADDR_W = xnfc->nand_base;
+	/* Set the driver entry points for MTD */
+	chip->dev_ready = pl353_nand_device_ready;
+	chip->select_chip = pl353_nand_select_chip;
+	/* If we don't set this delay driver sets 20us by default */
+	np = of_get_next_parent(xnfc->dev->of_node);
+	xnfc->mclk = of_clk_get(np, 0);
+	if (IS_ERR(xnfc->mclk)) {
+		dev_err(xnfc->dev, "Failed to retrieve MCK clk\n");
+		return PTR_ERR(xnfc->mclk);
+	}
+	chip->chip_delay = 30;
+	/* Set the device option and flash width */
+	chip->options = NAND_BUSWIDTH_AUTO;
+	chip->bbt_options = NAND_BBT_USE_FLASH;
+	platform_set_drvdata(pdev, xnfc);
+	chip->setup_data_interface = pl353_setup_data_interface;
+	/* first scan to find the device and get the page size */
+	if (nand_scan_ident(mtd, 1, NULL)) {
+		dev_err(xnfc->dev, "nand_scan_ident for NAND failed\n");
+		return -ENXIO;
+	}
+	ret = pl353_nand_ecc_init(mtd, &chip->ecc, chip->ecc.mode);
+	if (chip->options & NAND_BUSWIDTH_16)
+		pl353_smc_set_buswidth(PL353_SMC_MEM_WIDTH_16);
+	/* second phase scan */
+	if (nand_scan_tail(mtd)) {
+		dev_err(xnfc->dev, "nand_scan_tail for NAND failed\n");
+		return -ENXIO;
+	}
+
+	mtd_device_register(mtd, NULL, 0);
+
+	return 0;
+}
+
+/**
+ * pl353_nand_remove - Remove method for the NAND driver
+ * @pdev:	Pointer to the platform_device structure
+ *
+ * This function is called if the driver module is being unloaded. It frees all
+ * resources allocated to the device.
+ *
+ * Return:	0 on success or error value on failure
+ */
+static int pl353_nand_remove(struct platform_device *pdev)
+{
+	struct pl353_nand_info *xnfc = platform_get_drvdata(pdev);
+	struct mtd_info *mtd = nand_to_mtd(&xnfc->chip);
+
+	/* Release resources, unregister device */
+	nand_release(mtd);
+
+	return 0;
+}
+
+/* Match table for device tree binding */
+static const struct of_device_id pl353_nand_of_match[] = {
+	{ .compatible = "arm,pl353-nand-r2p1" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, pl353_nand_of_match);
+
+/*
+ * pl353_nand_driver - This structure defines the NAND subsystem platform driver
+ */
+static struct platform_driver pl353_nand_driver = {
+	.probe		= pl353_nand_probe,
+	.remove		= pl353_nand_remove,
+	.driver		= {
+		.name	= PL353_NAND_DRIVER_NAME,
+		.of_match_table = pl353_nand_of_match,
+	},
+};
+
+module_platform_driver(pl353_nand_driver);
+
+MODULE_AUTHOR("Xilinx, Inc.");
+MODULE_ALIAS("platform:" PL353_NAND_DRIVER_NAME);
+MODULE_DESCRIPTION("ARM PL353 NAND Flash Driver");
+MODULE_LICENSE("GPL");
-- 
2.7.4

Re: [[LINUX PATCH v10] 1/4] Devicetree: Add pl353 smc controller devicetree binding information

[Boris Brezillon]

Hi Naga,

Subject prefix should be "dt-bindings: memory: " not "Devicetree: ".

On Thu, 21 Jun 2018 12:12:28 +0530
Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com> wrote:

> Add pl353 static memory controller devicetree binding information.
> 
> Signed-off-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
> ---
> Changes in v10:
>  - Corrected the typos like "should be" to "Must be" and nand to NAND etc..
>  - Removed padding to describe size-cells and address-cells
>  - Removed timing parameters from DT, and added ->setup_data_interface() hook
>    to the driver to read the SDR timings
>  - Modified label name from "pl353smcc_0: pl353smcc@e000e000" to
>    "smcc: memory-controller@e000e000" as suggested by Miquel
> Changes in v9:
>  - Addressed below comments given by Randy Dunlap and Miquel Raynal
>  - Typos
>  - Added extra documentation that explains the HW ECC limitation with SMC
>    (Comments given to v8: https://lkml.org/lkml/2018/3/22/23)
> Changes in v8:
>  - None
> Changes in v7:
>  - Corrected clocks description
>  - prefixed '#' for address and size cells
> Changes in v6:
>  - None
> Changes in v5:
>  - Removed timing properties
> Changes in v4:
>  - none
> Changes in v3:
>  - none
> Changes in v2:
>  - modified timing binding info as per onfi timing parameters
>  - add suffix nano second as timing unit
>  - modified the clock names as per the IP spec
> ---
>  .../bindings/memory-controllers/pl353-smc.txt      | 41 ++++++++++++++++++++++
>  1 file changed, 41 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt
> 
> diff --git a/Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt b/Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt
> new file mode 100644
> index 0000000..8b4c65e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt
> @@ -0,0 +1,41 @@
> +Device tree bindings for ARM PL353 static memory controller
> +
> +PL353 static memory controller supports two kinds of memory
> +interfaces.i.e NAND and SRAM/NOR interfaces.
> +The actual devices are instantiated from the child nodes of pl353 smc node.
> +
> +Required properties:
> +- compatible		: Must be "arm,pl353-smc-r2p1"
> +- reg			: Controller registers map and length.
> +- clock-names		: List of input clock names - "ref_clk", "aper_clk"
> +			  (See clock bindings for details).
> +- clocks		: Clock phandles (see clock bindings for details).
> +- address-cells		: Must be 1.
> +- size-cells		: Must be 1.
> +
> +Child nodes:
> + For NAND the "arm,pl353-nand-r2p1" and for NOR the "cfi-flash" drivers are
> +supported as child nodes.
> +
> +for NAND partition information please refer the below file
> +Documentation/devicetree/bindings/mtd/partition.txt
> +
> +Example:
> +	smcc: memory-controller@e000e000
> +			compatible = "arm,pl353-smc-r2p1"
> +			clock-names = "memclk", "aclk";
> +			clocks = <&clkc 11>, <&clkc 44>;
> +			reg = <0xe000e000 0x1000>;
> +			#address-cells = <1>;
> +			#size-cells = <1>;
> +			ranges;
> +			nand_0: flash@e1000000 {
> +				compatible = "arm,pl353-nand-r2p1"
> +				reg = <0xe1000000 0x1000000>;
> +				(...)
> +			};
> +			nor0: flash@e2000000 {
> +				compatible = "cfi-flash";
> +				reg = <0xe2000000 0x2000000>;
> +			};
> +	};

I had a look at the PL353 TRM, and the block diagram looks very similar
to the atmel EBI/SMC one. AHB/AXI memory ranges that are used to
interact with the memories are assigned CS ids, which can then be used
to configure the timings (and other kind of stuff). I think you should
have #address-cells = <2>, the first cell encoding the CS id, and the
second one, the memory offset within the reserved range for this CS id.
See the atmel,ebi binding [1].

Regards,

Boris

[1]https://elixir.bootlin.com/linux/v4.18-rc2/source/Documentation/devicetree/bindings/memory-controllers/atmel,ebi.txt

Re: [[LINUX PATCH v10] 3/4] Documentation: nand: pl353: Add documentation for controller and driver

[Boris Brezillon]

On Thu, 21 Jun 2018 12:12:30 +0530
Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com> wrote:

> Added notes about the controller and driver.
> 
> Signed-off-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
> ---
> Changes in v10:
>  - None
> Changes in v9:
>  - Addressed the comments given by Miquel and Randy
> Changes in v8
>  - None
> Changes in v7:
> - None
> Changes in v6:
> - None
> Changes in v5:
> - Fixed the review comments
> Changes in v4:
> - None
> ---
>  Documentation/mtd/nand/pl353-nand.txt | 99 +++++++++++++++++++++++++++++++++++
>  1 file changed, 99 insertions(+)
>  create mode 100644 Documentation/mtd/nand/pl353-nand.txt

Can we put these information directly in the driver instead of having
yet another place where we have things partially documented? I just
discovered a doc for the pxa NAND controller in this directory because
of this patch, which kind of proves my point :-).

> 
> diff --git a/Documentation/mtd/nand/pl353-nand.txt b/Documentation/mtd/nand/pl353-nand.txt
> new file mode 100644
> index 0000000..c352c87
> --- /dev/null
> +++ b/Documentation/mtd/nand/pl353-nand.txt
> @@ -0,0 +1,99 @@
> +This document provides some notes about the ARM pl353 SMC controller used in
> +Zynq SOC and confined to NAND specific details.
> +
> +Overview of the controller
> +==========================
> +	The SMC (PL353) supports two memory interfaces:
> +	Interface 0 type SRAM.
> +	Interface 1 type NAND.
> +	This configuration supports the following configurable options:
> +	   . 32-bit or 64-bit AXI data width
> +	   . 8-bit, 16-bit, or 32-bit memory data width for interface 0
> +	   . 8-bit, or 16-bit memory data width for interface 1
> +	   . 1-4 chip selects on each interface
> +	   . SLC ECC block for interface 1
> +
> +For more information, refer the below link for TRM
> +http://infocenter.arm.com/help/topic/com.arm.doc.ddi0380g/DDI0380G_smc_pl350_series_r2p1_trm.pdf
> +
> +NAND memory accesses
> +====================
> +	. Two phase NAND accesses
> +	. NAND command phase transfers
> +	. NAND data phase transfers
> +
> +Two phase NAND accesses
> +	The SMC defines two phases of commands when transferring data to or from
> +NAND flash.
> +
> +Command phase
> +	Commands and optional address information are written to the NAND flash.
> +The command and address can be associated with either a data phase operation to
> +write to or read from the array, or a status/ID register transfer.
> +
> +Data phase
> + Data is either written to or read from the NAND flash. This data can be either
> +data transferred to or from the array, or status/ID register information.
> +
> +NAND AXI address setup
> +       AXI address      Command phase      Data phase
> +	[31:24]         Chip address       Chip address
> +	[23]            NoOfAddCycles_2    Reserved
> +	[22]            NoOfAddCycles_1    Reserved
> +	[21]            NoOfAddCycles_0    ClearCS
> +	[20]            End command valid  End command valid
> +	[19]            0                  1
> +	[18:11]         End command        End command
> +	[10:3]          Start command      [10] ECC Last
> +					   [9:3] Reserved
> +	[2:0]           Reserved           Reserved
> +
> +ECC
> +===
> +    It operates on a number of 512 byte blocks of NAND memory and can be
> +programmed to store the ECC codes after the data in memory. For writes,
> +the ECC is written to the spare area of the page. For reads, the result of
> +a block ECC check are made available to the device driver.
> +
> +------------------------------------------------------------------------
> +|               n * 512 blocks                  | extra  | ecc    |     |
> +|                                               | block  | codes  |     |
> +------------------------------------------------------------------------
> +
> +The ECC calculation uses a simple Hamming code, using 1-bit correction 2-bit
> +detection. It starts when a valid read or write command with a 512 byte aligned
> +address is detected on the memory interface.
> +
> +Driver details
> +==============
> +	The NAND driver has dependency with the pl353_smc memory controller
> +driver for initializing the NAND timing parameters, bus width, ECC modes,
> +control and status information.
> +
> +Since the controller expects that the chip select bit would be cleared for the
> +last data transfer i.e last 4 data bytes, the existing nand page
> +read/write routines for soft ECC and ECC none modes will not work. So, in order
> +to make this driver work, it always updates the ECC mode as HW ECC and
> +implements the page read/write functions for supporting the SW ECC.
> +i.e. There is a limitation in SMC controller, that we must set ECC LAST on
> +last data phase access, to tell ECC block not to expect any data further.
> +Ex:  When number of ECC STEPS are 4, then till 3 we will write to flash
> +using SMC with HW ECC enabled. And for the last ECC STEP, we will subtract
> +4bytes from page size, and will initiate a transfer. And the remaining 4 as
> +one more transfer with ECC_LAST bit set in NAND data phase register to notify
> +ECC block not to expect any more data. The last block should be align with end
> +of 512 byte block. Because of this limitation, we are not using core routines.
> +
> +HW ECC mode:
> +	Up to 2K page size is supported and beyond that it returns
> +-ENOTSUPPORT error. If the flash has on-die ECC controller then the
> +priority is given to the on-die ECC controller. Also the current
> +implementation has support for up to 64 bytes of OOB data.
> +
> +SW ECC mode:
> +	It supports all the page sizes. But since, Zynq SOC bootrom uses
> +HW ECC for the devices that have page <= 2K. so, When the kernel is not
> +aware of the ECC mode, it uses HW ECC by default.
> +
> +For devicetree binding information please refer to the below dt binding file
> +Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt.

RE: [[LINUX PATCH v10] 3/4] Documentation: nand: pl353: Add documentation for controller and driver

[Naga Sureshkumar Relli]

Hi Boris,

> -----Original Message-----
> From: Boris Brezillon [mailto:boris.brezillon@bootlin.com]
> Sent: Monday, June 25, 2018 2:24 AM
> To: Naga Sureshkumar Relli <nagasure@xilinx.com>
> Cc: richard@nod.at; dwmw2@infradead.org; computersforpeace@gmail.com;
> marek.vasut@gmail.com; f.fainelli@gmail.com; mmayer@broadcom.com; rogerq@ti.com;
> ladis@linux-mips.org; ada@thorsis.com; honghui.zhang@mediatek.com;
> miquel.raynal@bootlin.com; nagasureshkumarrelli@gmail.com; Michal Simek
> <michals@xilinx.com>; linux-mtd@lists.infradead.org; linux-kernel@vger.kernel.org
> Subject: Re: [[LINUX PATCH v10] 3/4] Documentation: nand: pl353: Add documentation
> for controller and driver
> 
> On Thu, 21 Jun 2018 12:12:30 +0530
> Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com> wrote:
> 
> > Added notes about the controller and driver.
> >
> > Signed-off-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
> > ---
> > Changes in v10:
> >  - None
> > Changes in v9:
> >  - Addressed the comments given by Miquel and Randy
> > Changes in v8
> >  - None
> > Changes in v7:
> > - None
> > Changes in v6:
> > - None
> > Changes in v5:
> > - Fixed the review comments
> > Changes in v4:
> > - None
> > ---
> >  Documentation/mtd/nand/pl353-nand.txt | 99
> +++++++++++++++++++++++++++++++++++
> >  1 file changed, 99 insertions(+)
> >  create mode 100644 Documentation/mtd/nand/pl353-nand.txt
> 
> Can we put these information directly in the driver instead of having
> yet another place where we have things partially documented? I just
> discovered a doc for the pxa NAND controller in this directory because
> of this patch, which kind of proves my point :-).
Ok, but could you please explain where to put in driver?
Do you mean, as comments inside drivers/mtd/raw/pl353-nand.c?

> 
> >
> > diff --git a/Documentation/mtd/nand/pl353-nand.txt b/Documentation/mtd/nand/pl353-
> nand.txt
> > new file mode 100644
> > index 0000000..c352c87
> > --- /dev/null
> > +++ b/Documentation/mtd/nand/pl353-nand.txt
> > @@ -0,0 +1,99 @@
> > +This document provides some notes about the ARM pl353 SMC controller used in
> > +Zynq SOC and confined to NAND specific details.
> > +
> > +Overview of the controller
> > +==========================
> > +	The SMC (PL353) supports two memory interfaces:
> > +	Interface 0 type SRAM.
> > +	Interface 1 type NAND.
> > +	This configuration supports the following configurable options:
> > +	   . 32-bit or 64-bit AXI data width
> > +	   . 8-bit, 16-bit, or 32-bit memory data width for interface 0
> > +	   . 8-bit, or 16-bit memory data width for interface 1
> > +	   . 1-4 chip selects on each interface
> > +	   . SLC ECC block for interface 1
> > +
> > +For more information, refer the below link for TRM
> >
> +http://infocenter.arm.com/help/topic/com.arm.doc.ddi0380g/DDI0380G_smc_pl350_series
> _r2p1_trm.pdf
> > +
> > +NAND memory accesses
> > +====================
> > +	. Two phase NAND accesses
> > +	. NAND command phase transfers
> > +	. NAND data phase transfers
> > +
> > +Two phase NAND accesses
> > +	The SMC defines two phases of commands when transferring data to or from
> > +NAND flash.
> > +
> > +Command phase
> > +	Commands and optional address information are written to the NAND flash.
> > +The command and address can be associated with either a data phase operation to
> > +write to or read from the array, or a status/ID register transfer.
> > +
> > +Data phase
> > + Data is either written to or read from the NAND flash. This data can be either
> > +data transferred to or from the array, or status/ID register information.
> > +
> > +NAND AXI address setup
> > +       AXI address      Command phase      Data phase
> > +	[31:24]         Chip address       Chip address
> > +	[23]            NoOfAddCycles_2    Reserved
> > +	[22]            NoOfAddCycles_1    Reserved
> > +	[21]            NoOfAddCycles_0    ClearCS
> > +	[20]            End command valid  End command valid
> > +	[19]            0                  1
> > +	[18:11]         End command        End command
> > +	[10:3]          Start command      [10] ECC Last
> > +					   [9:3] Reserved
> > +	[2:0]           Reserved           Reserved
> > +
> > +ECC
> > +===
> > +    It operates on a number of 512 byte blocks of NAND memory and can be
> > +programmed to store the ECC codes after the data in memory. For writes,
> > +the ECC is written to the spare area of the page. For reads, the result of
> > +a block ECC check are made available to the device driver.
> > +
> > +------------------------------------------------------------------------
> > +|               n * 512 blocks                  | extra  | ecc    |     |
> > +|                                               | block  | codes  |     |
> > +------------------------------------------------------------------------
> > +
> > +The ECC calculation uses a simple Hamming code, using 1-bit correction 2-bit
> > +detection. It starts when a valid read or write command with a 512 byte aligned
> > +address is detected on the memory interface.
> > +
> > +Driver details
> > +==============
> > +	The NAND driver has dependency with the pl353_smc memory controller
> > +driver for initializing the NAND timing parameters, bus width, ECC modes,
> > +control and status information.
> > +
> > +Since the controller expects that the chip select bit would be cleared for the
> > +last data transfer i.e last 4 data bytes, the existing nand page
> > +read/write routines for soft ECC and ECC none modes will not work. So, in order
> > +to make this driver work, it always updates the ECC mode as HW ECC and
> > +implements the page read/write functions for supporting the SW ECC.
> > +i.e. There is a limitation in SMC controller, that we must set ECC LAST on
> > +last data phase access, to tell ECC block not to expect any data further.
> > +Ex:  When number of ECC STEPS are 4, then till 3 we will write to flash
> > +using SMC with HW ECC enabled. And for the last ECC STEP, we will subtract
> > +4bytes from page size, and will initiate a transfer. And the remaining 4 as
> > +one more transfer with ECC_LAST bit set in NAND data phase register to notify
> > +ECC block not to expect any more data. The last block should be align with end
> > +of 512 byte block. Because of this limitation, we are not using core routines.
> > +
> > +HW ECC mode:
> > +	Up to 2K page size is supported and beyond that it returns
> > +-ENOTSUPPORT error. If the flash has on-die ECC controller then the
> > +priority is given to the on-die ECC controller. Also the current
> > +implementation has support for up to 64 bytes of OOB data.
> > +
> > +SW ECC mode:
> > +	It supports all the page sizes. But since, Zynq SOC bootrom uses
> > +HW ECC for the devices that have page <= 2K. so, When the kernel is not
> > +aware of the ECC mode, it uses HW ECC by default.
> > +
> > +For devicetree binding information please refer to the below dt binding file
> > +Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt.

Thanks,
Naga Sureshkumar Relli.

RE: [[LINUX PATCH v10] 1/4] Devicetree: Add pl353 smc controller devicetree binding information

[Naga Sureshkumar Relli]

Hi Boris,


> -----Original Message-----
> From: Boris Brezillon [mailto:boris.brezillon@bootlin.com]
> Sent: Monday, June 25, 2018 2:10 AM
> To: Naga Sureshkumar Relli <nagasure@xilinx.com>
> Cc: richard@nod.at; dwmw2@infradead.org; computersforpeace@gmail.com;
> marek.vasut@gmail.com; f.fainelli@gmail.com; mmayer@broadcom.com; rogerq@ti.com;
> ladis@linux-mips.org; ada@thorsis.com; honghui.zhang@mediatek.com;
> miquel.raynal@bootlin.com; nagasureshkumarrelli@gmail.com; Michal Simek
> <michals@xilinx.com>; linux-mtd@lists.infradead.org; linux-kernel@vger.kernel.org
> Subject: Re: [[LINUX PATCH v10] 1/4] Devicetree: Add pl353 smc controller devicetree
> binding information
> 
> Hi Naga,
> 
> Subject prefix should be "dt-bindings: memory: " not "Devicetree: ".
Ok, I will change it.

> 
> On Thu, 21 Jun 2018 12:12:28 +0530
> Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com> wrote:
> 
> > Add pl353 static memory controller devicetree binding information.
> >
> > Signed-off-by: Naga Sureshkumar Relli
> > <naga.sureshkumar.relli@xilinx.com>
> > ---
> > Changes in v10:
> >  - Corrected the typos like "should be" to "Must be" and nand to NAND etc..
> >  - Removed padding to describe size-cells and address-cells
> >  - Removed timing parameters from DT, and added ->setup_data_interface() hook
> >    to the driver to read the SDR timings
> >  - Modified label name from "pl353smcc_0: pl353smcc@e000e000" to
> >    "smcc: memory-controller@e000e000" as suggested by Miquel Changes
> > in v9:
> >  - Addressed below comments given by Randy Dunlap and Miquel Raynal
> >  - Typos
> >  - Added extra documentation that explains the HW ECC limitation with SMC
> >    (Comments given to v8: https://lkml.org/lkml/2018/3/22/23)
> > Changes in v8:
> >  - None
> > Changes in v7:
> >  - Corrected clocks description
> >  - prefixed '#' for address and size cells Changes in v6:
> >  - None
> > Changes in v5:
> >  - Removed timing properties
> > Changes in v4:
> >  - none
> > Changes in v3:
> >  - none
> > Changes in v2:
> >  - modified timing binding info as per onfi timing parameters
> >  - add suffix nano second as timing unit
> >  - modified the clock names as per the IP spec
> > ---
> >  .../bindings/memory-controllers/pl353-smc.txt      | 41
> ++++++++++++++++++++++
> >  1 file changed, 41 insertions(+)
> >  create mode 100644
> > Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt
> >
> > diff --git
> > a/Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt
> > b/Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt
> > new file mode 100644
> > index 0000000..8b4c65e
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/memory-controllers/pl353-smc.t
> > +++ xt
> > @@ -0,0 +1,41 @@
> > +Device tree bindings for ARM PL353 static memory controller
> > +
> > +PL353 static memory controller supports two kinds of memory
> > +interfaces.i.e NAND and SRAM/NOR interfaces.
> > +The actual devices are instantiated from the child nodes of pl353 smc node.
> > +
> > +Required properties:
> > +- compatible		: Must be "arm,pl353-smc-r2p1"
> > +- reg			: Controller registers map and length.
> > +- clock-names		: List of input clock names - "ref_clk", "aper_clk"
> > +			  (See clock bindings for details).
> > +- clocks		: Clock phandles (see clock bindings for details).
> > +- address-cells		: Must be 1.
> > +- size-cells		: Must be 1.
> > +
> > +Child nodes:
> > + For NAND the "arm,pl353-nand-r2p1" and for NOR the "cfi-flash"
> > +drivers are supported as child nodes.
> > +
> > +for NAND partition information please refer the below file
> > +Documentation/devicetree/bindings/mtd/partition.txt
> > +
> > +Example:
> > +	smcc: memory-controller@e000e000
> > +			compatible = "arm,pl353-smc-r2p1"
> > +			clock-names = "memclk", "aclk";
> > +			clocks = <&clkc 11>, <&clkc 44>;
> > +			reg = <0xe000e000 0x1000>;
> > +			#address-cells = <1>;
> > +			#size-cells = <1>;
> > +			ranges;
> > +			nand_0: flash@e1000000 {
> > +				compatible = "arm,pl353-nand-r2p1"
> > +				reg = <0xe1000000 0x1000000>;
> > +				(...)
> > +			};
> > +			nor0: flash@e2000000 {
> > +				compatible = "cfi-flash";
> > +				reg = <0xe2000000 0x2000000>;
> > +			};
> > +	};
> 
> I had a look at the PL353 TRM, and the block diagram looks very similar to the atmel
> EBI/SMC one. AHB/AXI memory ranges that are used to interact with the memories are
> assigned CS ids, which can then be used to configure the timings (and other kind of stuff). I
> think you should have #address-cells = <2>, the first cell encoding the CS id, and the second
> one, the memory offset within the reserved range for this CS id.
> See the atmel,ebi binding [1].
> 
To my previous patch, as per your comments, I modified reading timing parameters from dts
To nand_setup_data_interface() hook,
But I didn't see the CS implementation as per atmel EBI driver.
Sure, I will update like that and will send v11.

Thanks,
Naga Sureshkumar Relli

> Regards,
> 
> Boris
> 
> [1]https://elixir.bootlin.com/linux/v4.18-
> rc2/source/Documentation/devicetree/bindings/memory-controllers/atmel,ebi.txt

Re: [[LINUX PATCH v10] 3/4] Documentation: nand: pl353: Add documentation for controller and driver

[Boris Brezillon]

On Mon, 25 Jun 2018 08:56:41 +0000
Naga Sureshkumar Relli <nagasure@xilinx.com> wrote:

> Hi Boris,
> 
> > -----Original Message-----
> > From: Boris Brezillon [mailto:boris.brezillon@bootlin.com]
> > Sent: Monday, June 25, 2018 2:24 AM
> > To: Naga Sureshkumar Relli <nagasure@xilinx.com>
> > Cc: richard@nod.at; dwmw2@infradead.org; computersforpeace@gmail.com;
> > marek.vasut@gmail.com; f.fainelli@gmail.com; mmayer@broadcom.com; rogerq@ti.com;
> > ladis@linux-mips.org; ada@thorsis.com; honghui.zhang@mediatek.com;
> > miquel.raynal@bootlin.com; nagasureshkumarrelli@gmail.com; Michal Simek
> > <michals@xilinx.com>; linux-mtd@lists.infradead.org; linux-kernel@vger.kernel.org
> > Subject: Re: [[LINUX PATCH v10] 3/4] Documentation: nand: pl353: Add documentation
> > for controller and driver
> > 
> > On Thu, 21 Jun 2018 12:12:30 +0530
> > Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com> wrote:
> >   
> > > Added notes about the controller and driver.
> > >
> > > Signed-off-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
> > > ---
> > > Changes in v10:
> > >  - None
> > > Changes in v9:
> > >  - Addressed the comments given by Miquel and Randy
> > > Changes in v8
> > >  - None
> > > Changes in v7:
> > > - None
> > > Changes in v6:
> > > - None
> > > Changes in v5:
> > > - Fixed the review comments
> > > Changes in v4:
> > > - None
> > > ---
> > >  Documentation/mtd/nand/pl353-nand.txt | 99  
> > +++++++++++++++++++++++++++++++++++  
> > >  1 file changed, 99 insertions(+)
> > >  create mode 100644 Documentation/mtd/nand/pl353-nand.txt  
> > 
> > Can we put these information directly in the driver instead of having
> > yet another place where we have things partially documented? I just
> > discovered a doc for the pxa NAND controller in this directory because
> > of this patch, which kind of proves my point :-).  
> Ok, but could you please explain where to put in driver?
> Do you mean, as comments inside drivers/mtd/raw/pl353-nand.c?

Yes. Either inline, next to the relevant section of code, or at the
beginning of the file.

RE: [[LINUX PATCH v10] 1/4] Devicetree: Add pl353 smc controller devicetree binding information

[Naga Sureshkumar Relli]

Hi Boris,

> -----Original Message-----
> From: Naga Sureshkumar Relli [mailto:nagasure@xilinx.com]
> Sent: Monday, June 25, 2018 2:30 PM
> To: Boris Brezillon <boris.brezillon@bootlin.com>
> Cc: richard@nod.at; dwmw2@infradead.org; computersforpeace@gmail.com;
> marek.vasut@gmail.com; f.fainelli@gmail.com; mmayer@broadcom.com; rogerq@ti.com;
> ladis@linux-mips.org; ada@thorsis.com; honghui.zhang@mediatek.com;
> miquel.raynal@bootlin.com; nagasureshkumarrelli@gmail.com; Michal Simek
> <michals@xilinx.com>; linux-mtd@lists.infradead.org; linux-kernel@vger.kernel.org
> Subject: RE: [[LINUX PATCH v10] 1/4] Devicetree: Add pl353 smc controller devicetree
> binding information
> 
> Hi Boris,
> 
> 
> > -----Original Message-----
> > From: Boris Brezillon [mailto:boris.brezillon@bootlin.com]
> > Sent: Monday, June 25, 2018 2:10 AM
> > To: Naga Sureshkumar Relli <nagasure@xilinx.com>
> > Cc: richard@nod.at; dwmw2@infradead.org; computersforpeace@gmail.com;
> > marek.vasut@gmail.com; f.fainelli@gmail.com; mmayer@broadcom.com;
> > rogerq@ti.com; ladis@linux-mips.org; ada@thorsis.com;
> > honghui.zhang@mediatek.com; miquel.raynal@bootlin.com;
> > nagasureshkumarrelli@gmail.com; Michal Simek <michals@xilinx.com>;
> > linux-mtd@lists.infradead.org; linux-kernel@vger.kernel.org
> > Subject: Re: [[LINUX PATCH v10] 1/4] Devicetree: Add pl353 smc
> > controller devicetree binding information
> >
> > Hi Naga,
> >
> > Subject prefix should be "dt-bindings: memory: " not "Devicetree: ".
> Ok, I will change it.
> 
> >
> > On Thu, 21 Jun 2018 12:12:28 +0530
> > Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com> wrote:
> >
> > > Add pl353 static memory controller devicetree binding information.
> > >
> > > Signed-off-by: Naga Sureshkumar Relli
> > > <naga.sureshkumar.relli@xilinx.com>
> > > ---
> > > Changes in v10:
> > >  - Corrected the typos like "should be" to "Must be" and nand to NAND etc..
> > >  - Removed padding to describe size-cells and address-cells
> > >  - Removed timing parameters from DT, and added ->setup_data_interface() hook
> > >    to the driver to read the SDR timings
> > >  - Modified label name from "pl353smcc_0: pl353smcc@e000e000" to
> > >    "smcc: memory-controller@e000e000" as suggested by Miquel Changes
> > > in v9:
> > >  - Addressed below comments given by Randy Dunlap and Miquel Raynal
> > >  - Typos
> > >  - Added extra documentation that explains the HW ECC limitation with SMC
> > >    (Comments given to v8: https://lkml.org/lkml/2018/3/22/23)
> > > Changes in v8:
> > >  - None
> > > Changes in v7:
> > >  - Corrected clocks description
> > >  - prefixed '#' for address and size cells Changes in v6:
> > >  - None
> > > Changes in v5:
> > >  - Removed timing properties
> > > Changes in v4:
> > >  - none
> > > Changes in v3:
> > >  - none
> > > Changes in v2:
> > >  - modified timing binding info as per onfi timing parameters
> > >  - add suffix nano second as timing unit
> > >  - modified the clock names as per the IP spec
> > > ---
> > >  .../bindings/memory-controllers/pl353-smc.txt      | 41
> > ++++++++++++++++++++++
> > >  1 file changed, 41 insertions(+)
> > >  create mode 100644
> > > Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt
> > >
> > > diff --git
> > > a/Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt
> > > b/Documentation/devicetree/bindings/memory-controllers/pl353-smc.txt
> > > new file mode 100644
> > > index 0000000..8b4c65e
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/memory-controllers/pl353-smc
> > > +++ .t
> > > +++ xt
> > > @@ -0,0 +1,41 @@
> > > +Device tree bindings for ARM PL353 static memory controller
> > > +
> > > +PL353 static memory controller supports two kinds of memory
> > > +interfaces.i.e NAND and SRAM/NOR interfaces.
> > > +The actual devices are instantiated from the child nodes of pl353 smc node.
> > > +
> > > +Required properties:
> > > +- compatible		: Must be "arm,pl353-smc-r2p1"
> > > +- reg			: Controller registers map and length.
> > > +- clock-names		: List of input clock names - "ref_clk", "aper_clk"
> > > +			  (See clock bindings for details).
> > > +- clocks		: Clock phandles (see clock bindings for details).
> > > +- address-cells		: Must be 1.
> > > +- size-cells		: Must be 1.
> > > +
> > > +Child nodes:
> > > + For NAND the "arm,pl353-nand-r2p1" and for NOR the "cfi-flash"
> > > +drivers are supported as child nodes.
> > > +
> > > +for NAND partition information please refer the below file
> > > +Documentation/devicetree/bindings/mtd/partition.txt
> > > +
> > > +Example:
> > > +	smcc: memory-controller@e000e000
> > > +			compatible = "arm,pl353-smc-r2p1"
> > > +			clock-names = "memclk", "aclk";
> > > +			clocks = <&clkc 11>, <&clkc 44>;
> > > +			reg = <0xe000e000 0x1000>;
> > > +			#address-cells = <1>;
> > > +			#size-cells = <1>;
> > > +			ranges;
> > > +			nand_0: flash@e1000000 {
> > > +				compatible = "arm,pl353-nand-r2p1"
> > > +				reg = <0xe1000000 0x1000000>;
> > > +				(...)
> > > +			};
> > > +			nor0: flash@e2000000 {
> > > +				compatible = "cfi-flash";
> > > +				reg = <0xe2000000 0x2000000>;
> > > +			};
> > > +	};
> >
> > I had a look at the PL353 TRM, and the block diagram looks very
> > similar to the atmel EBI/SMC one. AHB/AXI memory ranges that are used
> > to interact with the memories are assigned CS ids, which can then be
> > used to configure the timings (and other kind of stuff). I think you
> > should have #address-cells = <2>, the first cell encoding the CS id, and the second one, the
> memory offset within the reserved range for this CS id.
> > See the atmel,ebi binding [1].
> >
> To my previous patch, as per your comments, I modified reading timing parameters from dts
> To nand_setup_data_interface() hook, But I didn't see the CS implementation as per atmel EBI
> driver.
> Sure, I will update like that and will send v11.

I have seen the atmel-ebi driver, it is doing more compare to PL353.
It works with 
drivers/mfd/
drivers/mtd/
drivers/memory/
but if we compare that with PL353 SMC, then
In nand case, we have only one CS and for NOR/SRAM we have 2 CS.
i.e
PL353 SMC -> NAND (1CS)
		NOR/SRAM(2CS).
So just asking, will there be any advantage if we do like that?
Because, for NOR/SRAM interface, the generic cfi-probe will take care and
For NAND, PL353 has just one NAND, hence asking.

Could you please explain a bit more?

Thanks,
Naga Sureshkumar Relli
> 
> Thanks,
> Naga Sureshkumar Relli
> 
> > Regards,
> >
> > Boris
> >
> > [1]https://elixir.bootlin.com/linux/v4.18-
> > rc2/source/Documentation/devicetree/bindings/memory-controllers/atmel,
> > ebi.txt

Re: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm pl353 smc nand interface

[Miquel Raynal]

Hi Naga,

This is not an issue at all but I think [PATCH vX Y/Z] is a preferred
and shorter suffix, you can create it automatically by using

        git format-patch -v X <first_commit>^..<last_commit> --cover-letter


On Thu, 21 Jun 2018 12:12:31 +0530, Naga Sureshkumar Relli
<naga.sureshkumar.relli@xilinx.com> wrote:

> Add driver for arm pl353 static memory controller nand interface with HW ECC
> support. This controller is used in Xilinx Zynq SoC for interfacing the NAND
> flash memory.
> 
> Signed-off-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
> ---
> Changes in 10:
>  - Typos correction like nand to NAND and soc to SOC etc..
>  - Defined macros for the values in pl353_nand_calculate_hwecc()
>  - Modifed ecc_status from int to char in pl353_nand_calculate_hwecc()
>  - Changed the return type form int to bool to the function
>    onehot()
>  - Removed udelay(1000) in pl353_cmd_function, as it is not required
>  - Dropped ecc->hwctl = NULL in pl353_ecc_init()
>  - Added an error message in pl353_ecc_init(), when there is no matching
>    oobsize
>  - Changed the variable from xnand to xnfc
>  - Added logic to get mtd->name from DT, if it is specified in DT
> Changes in v9:
>  - Addressed the below comments given by Miquel
>  - instead of using pl353_nand_write32, use directly writel_relaxed
>  - Fixed check patch warnings
>  - Renamed write_buf/read_buf to write_data_op/read_data_op
>  - use BIT macro instead of 1 << nr
>  - Use NAND_ROW_ADDR_3 flag
>  - Use nand_wait_ready()
>  - Removed swecc functions
>  - Use address cycles as per size, instead of reading it from Parameter page
>  - Instead of writing too many patterns, use optional property
> Changes in v8:
>  - Added exec_op() implementation
>  - Fixed the below v7 review comments
>  - removed mtd_info from pl353_nand_info struct
>  - Corrected ecc layout offsets
>  - Added on-die ecc support
> Changes in v7:
>  - Currently not implemented the memclk rate adjustments. I will
>    look into this later and once the basic driver is accepted.
>  - Fixed GPL licence ident
> Changes in v6:
>  - Fixed the checkpatch.pl reported warnings
>  - Using the address cycles information from the onfi param page
>    earlier it is hardcoded to 5 in driver
> Changes in v5:
>  - Configure the nand timing parameters as per the onfi spec Changes in v4:
>  - Updated the driver to sync with pl353_smc driver APIs
> Changes in v3:
>  - implemented the proper error codes
>  - further breakdown this patch to multiple sets
>  - added the controller and driver details to Documentation section
>  - updated the licenece to GPLv2
>  - reorganized the pl353_nand_ecc_init function
> Changes in v2:
>  - use "depends on" rather than "select" option in kconfig
>  - remove unused variable parts
> ---
>  drivers/mtd/nand/raw/Kconfig      |    7 +
>  drivers/mtd/nand/raw/Makefile     |    1 +
>  drivers/mtd/nand/raw/pl353_nand.c | 1309 +++++++++++++++++++++++++++++++++++++
>  3 files changed, 1317 insertions(+)
>  create mode 100644 drivers/mtd/nand/raw/pl353_nand.c
> 
> diff --git a/drivers/mtd/nand/raw/Kconfig b/drivers/mtd/nand/raw/Kconfig
> index 6871ff0..1c5d528 100644
> --- a/drivers/mtd/nand/raw/Kconfig
> +++ b/drivers/mtd/nand/raw/Kconfig
> @@ -530,4 +530,11 @@ config MTD_NAND_MTK
>  	  Enables support for NAND controller on MTK SoCs.
>  	  This controller is found on mt27xx, mt81xx, mt65xx SoCs.
>  
> +config MTD_NAND_PL353
> +	tristate "ARM Pl353 NAND flash driver"
> +	depends on MTD_NAND && ARM
> +	depends on PL353_SMC
> +	help
> +	  Enables support for PrimeCell Static Memory Controller PL353.
> +
>  endif # MTD_NAND
> diff --git a/drivers/mtd/nand/raw/Makefile b/drivers/mtd/nand/raw/Makefile
> index 165b7ef..1c702e1 100644
> --- a/drivers/mtd/nand/raw/Makefile
> +++ b/drivers/mtd/nand/raw/Makefile
> @@ -56,6 +56,7 @@ obj-$(CONFIG_MTD_NAND_HISI504)	        += hisi504_nand.o
>  obj-$(CONFIG_MTD_NAND_BRCMNAND)		+= brcmnand/
>  obj-$(CONFIG_MTD_NAND_QCOM)		+= qcom_nandc.o
>  obj-$(CONFIG_MTD_NAND_MTK)		+= mtk_ecc.o mtk_nand.o
> +obj-$(CONFIG_MTD_NAND_PL353)		+= pl353_nand.o
>  
>  nand-objs := nand_base.o nand_bbt.o nand_timings.o nand_ids.o
>  nand-objs += nand_amd.o
> diff --git a/drivers/mtd/nand/raw/pl353_nand.c b/drivers/mtd/nand/raw/pl353_nand.c
> new file mode 100644
> index 0000000..3a0acbd
> --- /dev/null
> +++ b/drivers/mtd/nand/raw/pl353_nand.c
> @@ -0,0 +1,1309 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * ARM PL353 NAND flash controller driver
> + *
> + * Copyright (C) 2017 Xilinx, Inc
> + * Author: Punnaiah chowdary kalluri <punnaiah@xilinx.com>
> + * Author: Naga Sureshkumar Relli <nagasure@xilinx.com>
> + *
> + */
> +
> +#include <linux/err.h>
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/ioport.h>
> +#include <linux/irq.h>
> +#include <linux/module.h>
> +#include <linux/moduleparam.h>
> +#include <linux/mtd/mtd.h>
> +#include <linux/mtd/rawnand.h>
> +#include <linux/mtd/nand_ecc.h>
> +#include <linux/mtd/partitions.h>
> +#include <linux/of_address.h>
> +#include <linux/of_device.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/pl353-smc.h>
> +#include <linux/clk.h>
> +
> +#define PL353_NAND_DRIVER_NAME "pl353-nand"
> +
> +/* NAND flash driver defines */
> +#define PL353_NAND_CMD_PHASE	1	/* End command valid in command phase */
> +#define PL353_NAND_DATA_PHASE	2	/* End command valid in data phase */
> +#define PL353_NAND_ECC_SIZE	512	/* Size of data for ECC operation */
> +
> +/* Flash memory controller operating parameters */
> +
> +#define PL353_NAND_ECC_CONFIG	(BIT(4)  |	/* ECC read at end of page */ \
> +				 (0 << 5))	/* No Jumping */
> +
> +/* AXI Address definitions */
> +#define START_CMD_SHIFT		3
> +#define END_CMD_SHIFT		11
> +#define END_CMD_VALID_SHIFT	20
> +#define ADDR_CYCLES_SHIFT	21
> +#define CLEAR_CS_SHIFT		21
> +#define ECC_LAST_SHIFT		10
> +#define COMMAND_PHASE		(0 << 19)
> +#define DATA_PHASE		BIT(19)
> +
> +#define PL353_NAND_ECC_LAST	BIT(ECC_LAST_SHIFT)	/* Set ECC_Last */
> +#define PL353_NAND_CLEAR_CS	BIT(CLEAR_CS_SHIFT)	/* Clear chip select */
> +
> +#define ONDIE_ECC_FEATURE_ADDR	0x90
> +#define PL353_NAND_ECC_BUSY_TIMEOUT	(1 * HZ)
> +#define PL353_NAND_DEV_BUSY_TIMEOUT	(1 * HZ)
> +#define PL353_NAND_LAST_TRANSFER_LENGTH	4
> +#define PL353_NAND_ECC_VALID_SHIFT	24
> +#define PL353_NAND_ECC_VALID_MASK	0x40
> +
> +struct pl353_nfc_op {
> +	u32 cmnds[4];
> +	u32 thirdrow;
> +	u32 type;
> +	u32 end_cmd;
> +	u32 addrs;
> +	bool wait;
> +	u32 len;
> +	u32 naddrs;
> +	unsigned int data_instr_idx;
> +	const struct nand_op_instr *data_instr;
> +	unsigned int rdy_timeout_ms;
> +	unsigned int rdy_delay_ns;
> +	unsigned int data_delay_ns;
> +	unsigned int cle_ale_delay_ns;
> +	u32 addr5;
> +	u32 addr6;
> +};
> +
> +/**
> + * struct pl353_nand_info - Defines the NAND flash driver instance
> + * @chip:		NAND chip information structure
> + * @nand_base:		Virtual address of the NAND flash device
> + * @end_cmd_pending:	End command is pending
> + * @end_cmd:		End command
> + * @row_addr_cycles:	Row address cycles
> + * @col_addr_cycles:	Column address cycles
> + * @address:		Page address
> + * @cmd_pending:	More command is needed

I'm still not ok with this structure.

The NAND controller entries must be separated from the NAND chip's. You
can get some inspiration from marvell_nand.c or sunxi_nand.c.

> + */
> +struct pl353_nand_info {
> +	struct nand_chip chip;
> +	struct device *dev;
> +	void __iomem *nand_base;
> +	unsigned long end_cmd_pending;
> +	unsigned long end_cmd;
> +	u8 addr_cycles;
> +	u32 address;
> +	u32 cmd_pending;
> +	struct completion complete;
> +	struct clk *mclk;
> +

Extra space

> +};
> +
> +static int pl353_ecc_ooblayout16_ecc(struct mtd_info *mtd, int section,
> +				     struct mtd_oob_region *oobregion)
> +{
> +	struct nand_chip *chip = mtd_to_nand(mtd);
> +
> +	if (section >= chip->ecc.steps)
> +		return -ERANGE;
> +
> +	oobregion->offset = (section * chip->ecc.bytes);
> +	oobregion->length = chip->ecc.bytes;
> +
> +	return 0;
> +}
> +
> +static int pl353_ecc_ooblayout16_free(struct mtd_info *mtd, int section,
> +				      struct mtd_oob_region *oobregion)
> +{
> +	struct nand_chip *chip = mtd_to_nand(mtd);
> +
> +	if (section >= chip->ecc.steps)
> +		return -ERANGE;
> +
> +	oobregion->offset = (section * chip->ecc.bytes) + 8;
> +	oobregion->length = 8;
> +
> +	return 0;
> +}
> +
> +static const struct mtd_ooblayout_ops pl353_ecc_ooblayout16_ops = {
> +	.ecc = pl353_ecc_ooblayout16_ecc,
> +	.free = pl353_ecc_ooblayout16_free,
> +};
> +
> +static int pl353_ecc_ooblayout64_ecc(struct mtd_info *mtd, int section,
> +				     struct mtd_oob_region *oobregion)
> +{
> +	struct nand_chip *chip = mtd_to_nand(mtd);
> +
> +	if (section >= chip->ecc.steps)
> +		return -ERANGE;
> +
> +	oobregion->offset = (section * chip->ecc.bytes) + 52;
> +	oobregion->length = chip->ecc.bytes;
> +
> +	return 0;
> +}
> +
> +static int pl353_ecc_ooblayout64_free(struct mtd_info *mtd, int section,
> +				      struct mtd_oob_region *oobregion)
> +{
> +	struct nand_chip *chip = mtd_to_nand(mtd);
> +
> +	if (section)
> +		return -ERANGE;
> +
> +	if (section >= chip->ecc.steps)
> +		return -ERANGE;
> +
> +	oobregion->offset = (section * chip->ecc.bytes) + 2;
> +	oobregion->length = 50;
> +
> +	return 0;
> +}
> +
> +static const struct mtd_ooblayout_ops pl353_ecc_ooblayout64_ops = {
> +	.ecc = pl353_ecc_ooblayout64_ecc,
> +	.free = pl353_ecc_ooblayout64_free,
> +};
> +
> +/* Generic flash bbt decriptors */
> +static u8 bbt_pattern[] = { 'B', 'b', 't', '0' };
> +static u8 mirror_pattern[] = { '1', 't', 'b', 'B' };
> +
> +static struct nand_bbt_descr bbt_main_descr = {
> +	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
> +		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
> +	.offs = 4,
> +	.len = 4,
> +	.veroffs = 20,
> +	.maxblocks = 4,
> +	.pattern = bbt_pattern
> +};
> +
> +static struct nand_bbt_descr bbt_mirror_descr = {
> +	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
> +		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
> +	.offs = 4,
> +	.len = 4,
> +	.veroffs = 20,
> +	.maxblocks = 4,
> +	.pattern = mirror_pattern
> +};
> +
> +/**
> + * pl353_nand_read_data_op - read chip data into buffer
> + * @chip:	Pointer to the NAND chip info structure
> + * @in:		Pointer to the buffer to store read data
> + * @len:	Number of bytes to read
> + * Return:	Always return zero
> + */
> +static int pl353_nand_read_data_op(struct nand_chip *chip,
> +				   u8 *in,
> +				   unsigned int len)
> +{
> +	int i;
> +
> +	if (IS_ALIGNED((uint32_t)in, sizeof(uint32_t)) &&
> +	    IS_ALIGNED(len, sizeof(uint32_t))) {
> +		u32 *ptr = (u32 *)in;
> +
> +		len /= 4;
> +		for (i = 0; i < len; i++)
> +			ptr[i] = readl(chip->IO_ADDR_R);

Please do not use IO_ADDR_R/W, these chip structure entries are
deprecated and might be removed anytime soon. Removing them will
simplify a lot all the functions where you do kind of unreadable pointer
operations around these value. This is really bad and I already told
you about it.

Please fix this and then I'll review the rest.

> +	} else {
> +		for (i = 0; i < len; i++)
> +			in[i] = readb(chip->IO_ADDR_R);
> +	}
> +
> +	return 0;
> +}
> +
> +/**
> + * pl353_nand_write_buf - write buffer to chip
> + * @mtd:	Pointer to the mtd info structure
> + * @buf:	Pointer to the buffer to store write data
> + * @len:	Number of bytes to write
> + */
> +static void pl353_nand_write_data_op(struct mtd_info *mtd, const u8 *buf,
> +				     int len)
> +{
> +	int i;
> +	struct nand_chip *chip = mtd_to_nand(mtd);
> +
> +	if (IS_ALIGNED((uint32_t)buf, sizeof(uint32_t)) &&
> +	    IS_ALIGNED(len, sizeof(uint32_t))) {
> +		u32 *ptr = (u32 *)buf;
> +
> +		len /= 4;
> +		for (i = 0; i < len; i++)
> +			writel(ptr[i], chip->IO_ADDR_W);
> +	} else {
> +		for (i = 0; i < len; i++)
> +			writeb(buf[i], chip->IO_ADDR_W);
> +	}
> +}
> +
> +/**
> + * pl353_nand_calculate_hwecc - Calculate Hardware ECC
> + * @mtd:	Pointer to the mtd_info structure
> + * @data:	Pointer to the page data
> + * @ecc:	Pointer to the ECC buffer where ECC data needs to be stored
> + *
> + * This function retrieves the Hardware ECC data from the controller and returns
> + * ECC data back to the MTD subsystem.
> + *
> + * Return:	0 on success or error value on failure
> + */
> +static int pl353_nand_calculate_hwecc(struct mtd_info *mtd,
> +				      const u8 *data, u8 *ecc)
> +{
> +	u32 ecc_value;
> +	u8 ecc_reg, ecc_byte, ecc_status;
> +	unsigned long timeout = jiffies + PL353_NAND_ECC_BUSY_TIMEOUT;

New line

> +	/* Wait till the ECC operation is complete or timeout */
> +	do {
> +		if (pl353_smc_ecc_is_busy())
> +			cpu_relax();
> +		else
> +			break;
> +	} while (!time_after_eq(jiffies, timeout));
> +
> +	if (time_after_eq(jiffies, timeout)) {
> +		pr_err("%s timed out\n", __func__);
> +		return -ETIMEDOUT;
> +	}
> +
> +	for (ecc_reg = 0; ecc_reg < 4; ecc_reg++) {
> +		/* Read ECC value for each block */
> +		ecc_value = pl353_smc_get_ecc_val(ecc_reg);
> +		ecc_status = (ecc_value >> PL353_NAND_ECC_VALID_SHIFT);
> +		/* ECC value valid */
> +		if (ecc_status & PL353_NAND_ECC_VALID_MASK) {
> +			for (ecc_byte = 0; ecc_byte < 3; ecc_byte++) {
> +				/* Copy ECC bytes to MTD buffer */
> +				*ecc = ~ecc_value & 0xFF;
> +				ecc_value = ecc_value >> 8;
> +				ecc++;
> +			}
> +		} else {
> +			pr_warn("%s status failed\n", __func__);
> +			return -1;
> +		}
> +	}

New line

> +	return 0;
> +}
> +
> +/**
> + * onehot - onehot function
> + * @value:	Value to check for onehot
> + *
> + * This function checks whether a value is onehot or not.
> + * onehot is if and only if onebit is set.
> + *
> + * Return:	1 if it is onehot else 0
> + */
> +static bool onehot(unsigned short value)
> +{
> +	return (value & (value - 1)) == 0;

Please use something from bitmap.c or bitops.h to do this.

> +}
> +
> +/**
> + * pl353_nand_correct_data - ECC correction function
> + * @mtd:	Pointer to the mtd_info structure
> + * @buf:	Pointer to the page data
> + * @read_ecc:	Pointer to the ECC value read from spare data area
> + * @calc_ecc:	Pointer to the calculated ECC value
> + *
> + * This function corrects the ECC single bit errors & detects 2-bit errors.
> + *
> + * Return:	0 if no ECC errors found
> + *		1 if single bit error found and corrected.
> + *		-1 if multiple uncorrectable ECC errors found.
> + */
> +static int pl353_nand_correct_data(struct mtd_info *mtd, unsigned char *buf,
> +				   unsigned char *read_ecc,
> +				   unsigned char *calc_ecc)
> +{
> +	unsigned char bit_addr;
> +	unsigned int byte_addr;
> +	unsigned short ecc_odd, ecc_even, read_ecc_lower, read_ecc_upper;
> +	unsigned short calc_ecc_lower, calc_ecc_upper;
> +
> +	read_ecc_lower = (read_ecc[0] | (read_ecc[1] << 8)) & 0xfff;
> +	read_ecc_upper = ((read_ecc[1] >> 4) | (read_ecc[2] << 4)) & 0xfff;
> +
> +	calc_ecc_lower = (calc_ecc[0] | (calc_ecc[1] << 8)) & 0xfff;
> +	calc_ecc_upper = ((calc_ecc[1] >> 4) | (calc_ecc[2] << 4)) & 0xfff;
> +
> +	ecc_odd = read_ecc_lower ^ calc_ecc_lower;
> +	ecc_even = read_ecc_upper ^ calc_ecc_upper;
> +
> +	/* no error */
> +	if (!ecc_odd && !ecc_even)
> +		return 0;
> +
> +	if (ecc_odd == (~ecc_even & 0xfff)) {
> +		/* bits [11:3] of error code is byte offset */
> +		byte_addr = (ecc_odd >> 3) & 0x1ff;

You might want to define these values.

> +		/* bits [2:0] of error code is bit offset */
> +		bit_addr = ecc_odd & 0x7;

Same here.

> +		/* Toggling error bit */
> +		buf[byte_addr] ^= (BIT(bit_addr));
> +		return 1;
> +	}

New line

> +	/* one error in parity */
> +	if (onehot(ecc_odd | ecc_even) == 1)
> +		return 1;
> +
> +	/* Uncorrectable error */
> +	return -1;
> +}
> +
> +static int pl353_dev_timeout(struct mtd_info *mtd, struct nand_chip *chip,
> +			     unsigned long timeout)
> +{
> +	if (timeout)
> +		timeout = jiffies + msecs_to_jiffies(timeout);
> +	else
> +		timeout = jiffies + PL353_NAND_DEV_BUSY_TIMEOUT;
> +
> +	do {
> +		if (chip->dev_ready(mtd))
> +			break;
> +		cpu_relax();
> +	} while (!time_after_eq(jiffies, timeout));

Isn't this a nand_wait_ready() equivalent?

> +
> +	if (time_after_eq(jiffies, timeout)) {
> +		pr_err("%s timed out\n", __func__);
> +		return -1;
> +	}
> +
> +	return 0;
> +}
> +
> +static void pl353_prepare_cmd(struct mtd_info *mtd, struct nand_chip *chip,
> +			      int page, int column, int start_cmd, int end_cmd,
> +			      bool read)
> +{
> +	unsigned long data_phase_addr;
> +	u32 end_cmd_valid = 0;
> +	void __iomem *cmd_addr;
> +	unsigned long cmd_phase_addr = 0, cmd_data = 0;
> +
> +	struct pl353_nand_info *xnfc =
> +		container_of(chip, struct pl353_nand_info, chip);
> +
> +	end_cmd_valid = read ? 1 : 0;
> +
> +	cmd_phase_addr = (unsigned long __force)xnfc->nand_base +
> +			 ((xnfc->addr_cycles
> +			 << ADDR_CYCLES_SHIFT) |
> +			 (end_cmd_valid << END_CMD_VALID_SHIFT) |
> +			 (COMMAND_PHASE) |
> +			 (end_cmd << END_CMD_SHIFT) |
> +			 (start_cmd << START_CMD_SHIFT));
> +	cmd_addr = (void __iomem * __force)cmd_phase_addr;
> +
> +	/* Get the data phase address */
> +	data_phase_addr = (unsigned long __force)xnfc->nand_base +
> +			  ((0x0 << CLEAR_CS_SHIFT) |
> +			  (0 << END_CMD_VALID_SHIFT) |
> +			  (DATA_PHASE) |
> +			  (end_cmd << END_CMD_SHIFT) |
> +			  (0x0 << ECC_LAST_SHIFT));
> +
> +	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
> +	chip->IO_ADDR_W = chip->IO_ADDR_R;
> +	if (chip->options & NAND_BUSWIDTH_16)
> +		column /= 2;
> +	cmd_data = column;
> +	if (mtd->writesize > PL353_NAND_ECC_SIZE) {
> +		cmd_data |= page << 16;
> +		/* Another address cycle for devices > 128MiB */
> +		if (chip->options & NAND_ROW_ADDR_3) {
> +			writel_relaxed(cmd_data, cmd_addr);
> +			cmd_data = (page >> 16);
> +		}
> +	} else {
> +		cmd_data |= page << 8;
> +	}
> +
> +	writel_relaxed(cmd_data, cmd_addr);
> +}
> +
> +/**
> + * pl353_nand_read_oob - [REPLACEABLE] the most common OOB data read function
> + * @mtd:	Pointer to the mtd info structure
> + * @chip:	Pointer to the NAND chip info structure
> + * @page:	Page number to read
> + *
> + * Return:	Always return zero
> + */
> +static int pl353_nand_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
> +			       int page)
> +{
> +	unsigned long data_phase_addr;
> +	u8 *p;
> +	struct pl353_nand_info *xnfc =
> +		container_of(chip, struct pl353_nand_info, chip);
> +	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
> +
> +	chip->pagebuf = -1;
> +	if (mtd->writesize < PL353_NAND_ECC_SIZE)
> +		return 0;
> +
> +	pl353_prepare_cmd(mtd, chip, page, mtd->writesize, NAND_CMD_READ0,
> +			  NAND_CMD_READSTART, 1);
> +
> +	ndelay(100);
> +	pl353_dev_timeout(mtd, chip, 0);
> +
> +	p = chip->oob_poi;
> +	pl353_nand_read_data_op(chip, p,
> +				(mtd->oobsize -
> +				PL353_NAND_LAST_TRANSFER_LENGTH));
> +	p += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
> +	data_phase_addr -= nand_offset;
> +	data_phase_addr |= PL353_NAND_CLEAR_CS;
> +	data_phase_addr += nand_offset;
> +	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
> +	pl353_nand_read_data_op(chip, p, PL353_NAND_LAST_TRANSFER_LENGTH);
> +
> +	return 0;
> +}
> +
> +/**
> + * pl353_nand_write_oob - [REPLACEABLE] the most common OOB data write function
> + * @mtd:	Pointer to the mtd info structure
> + * @chip:	Pointer to the NAND chip info structure
> + * @page:	Page number to write
> + *
> + * Return:	Zero on success and EIO on failure
> + */
> +static int pl353_nand_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
> +				int page)
> +{
> +	const u8 *buf = chip->oob_poi;
> +	unsigned long data_phase_addr;
> +	struct pl353_nand_info *xnfc =
> +		container_of(chip, struct pl353_nand_info, chip);
> +	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
> +	u32 addrcycles = 0;
> +
> +	chip->pagebuf = -1;
> +	addrcycles = xnfc->addr_cycles;
> +	pl353_prepare_cmd(mtd, chip, page, mtd->writesize, NAND_CMD_SEQIN,
> +			  NAND_CMD_PAGEPROG, 0);
> +	ndelay(100);
> +	pl353_nand_write_data_op(mtd, buf,
> +				 (mtd->oobsize -
> +				 PL353_NAND_LAST_TRANSFER_LENGTH));
> +	buf += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> +
> +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
> +	data_phase_addr -= nand_offset;
> +	data_phase_addr |= PL353_NAND_CLEAR_CS;
> +	data_phase_addr |= (1 << END_CMD_VALID_SHIFT);
> +	data_phase_addr += nand_offset;
> +	chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
> +	pl353_nand_write_data_op(mtd, buf, PL353_NAND_LAST_TRANSFER_LENGTH);
> +	nand_wait_ready(mtd);
> +
> +	return 0;
> +}
> +
> +/**
> + * pl353_nand_read_page_raw - [Intern] read raw page data without ecc
> + * @mtd:		Pointer to the mtd info structure
> + * @chip:		Pointer to the NAND chip info structure
> + * @buf:		Pointer to the data buffer
> + * @oob_required:	Caller requires OOB data read to chip->oob_poi
> + * @page:		Page number to read
> + *
> + * Return:	Always return zero
> + */
> +static int pl353_nand_read_page_raw(struct mtd_info *mtd,
> +				    struct nand_chip *chip,
> +				    u8 *buf, int oob_required, int page)
> +{
> +	unsigned long data_phase_addr;
> +	u8 *p;
> +	struct pl353_nand_info *xnfc =
> +		container_of(chip, struct pl353_nand_info, chip);
> +	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
> +
> +	pl353_nand_read_data_op(chip, buf, mtd->writesize);
> +	p = chip->oob_poi;
> +	pl353_nand_read_data_op(chip, p,
> +				(mtd->oobsize -
> +				PL353_NAND_LAST_TRANSFER_LENGTH));
> +	p += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> +
> +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
> +	data_phase_addr -= nand_offset;
> +	data_phase_addr |= PL353_NAND_CLEAR_CS;
> +	data_phase_addr += nand_offset;
> +	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
> +
> +	pl353_nand_read_data_op(chip, p, PL353_NAND_LAST_TRANSFER_LENGTH);
> +
> +	return 0;
> +}
> +
> +/**
> + * pl353_nand_write_page_raw - [Intern] raw page write function
> + * @mtd:		Pointer to the mtd info structure
> + * @chip:		Pointer to the NAND chip info structure
> + * @buf:		Pointer to the data buffer
> + * @oob_required:	Caller requires OOB data read to chip->oob_poi
> + * @page:		Page number to write
> + *
> + * Return:	Always return zero
> + */
> +static int pl353_nand_write_page_raw(struct mtd_info *mtd,
> +				     struct nand_chip *chip,
> +				     const u8 *buf, int oob_required,
> +				     int page)
> +{
> +	unsigned long data_phase_addr;
> +	u8 *p;
> +
> +	struct pl353_nand_info *xnfc =
> +		container_of(chip, struct pl353_nand_info, chip);
> +	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
> +
> +	pl353_nand_write_data_op(mtd, buf, mtd->writesize);
> +	p = chip->oob_poi;
> +	pl353_nand_write_data_op(mtd, p,
> +				 (mtd->oobsize -
> +				 PL353_NAND_LAST_TRANSFER_LENGTH));
> +	p += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> +
> +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
> +	data_phase_addr -= nand_offset;
> +	data_phase_addr |= PL353_NAND_CLEAR_CS;
> +	data_phase_addr |= (1 << END_CMD_VALID_SHIFT);
> +	data_phase_addr += nand_offset;
> +	chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
> +
> +	pl353_nand_write_data_op(mtd, p, PL353_NAND_LAST_TRANSFER_LENGTH);
> +
> +	return 0;
> +}
> +
> +/**
> + * nand_write_page_hwecc - Hardware ECC based page write function
> + * @mtd:		Pointer to the mtd info structure
> + * @chip:		Pointer to the NAND chip info structure
> + * @buf:		Pointer to the data buffer
> + * @oob_required:	Caller requires OOB data read to chip->oob_poi
> + * @page:		Page number to write
> + *
> + * This functions writes data and hardware generated ECC values in to the page.
> + *
> + * Return:	Always return zero
> + */
> +static int pl353_nand_write_page_hwecc(struct mtd_info *mtd,
> +				       struct nand_chip *chip,
> +				       const u8 *buf, int oob_required,
> +				       int page)
> +{
> +	int eccsize = chip->ecc.size;
> +	int eccsteps = chip->ecc.steps;
> +	u8 *ecc_calc = chip->ecc.calc_buf;
> +	u8 *oob_ptr;
> +	const u8 *p = buf;
> +	u32 ret;
> +	unsigned long data_phase_addr;
> +	struct pl353_nand_info *xnfc =
> +		container_of(chip, struct pl353_nand_info, chip);
> +	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
> +
> +	pl353_prepare_cmd(mtd, chip, page, 0, NAND_CMD_SEQIN,
> +			  NAND_CMD_PAGEPROG, 0);
> +	ndelay(100);
> +	for ( ; (eccsteps - 1); eccsteps--) {
> +		pl353_nand_write_data_op(mtd, p, eccsize);
> +		p += eccsize;
> +	}
> +	pl353_nand_write_data_op(mtd, p,
> +				 (eccsize - PL353_NAND_LAST_TRANSFER_LENGTH));
> +	p += (eccsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> +
> +	/* Set ECC Last bit to 1 */
> +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
> +	data_phase_addr -= nand_offset;
> +	data_phase_addr |= PL353_NAND_ECC_LAST;
> +	data_phase_addr += nand_offset;
> +	chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
> +	pl353_nand_write_data_op(mtd, p, PL353_NAND_LAST_TRANSFER_LENGTH);
> +
> +	p = buf;
> +	chip->ecc.calculate(mtd, p, &ecc_calc[0]);
> +
> +	/* Wait for ECC to be calculated and read the error values */
> +	ret = mtd_ooblayout_set_eccbytes(mtd, ecc_calc, chip->oob_poi,
> +					 0, chip->ecc.total);
> +	if (ret)
> +		return ret;
> +	/* Clear ECC last bit */
> +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
> +	data_phase_addr -= nand_offset;
> +	data_phase_addr &= ~PL353_NAND_ECC_LAST;
> +	data_phase_addr += nand_offset;
> +	chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
> +
> +	/* Write the spare area with ECC bytes */
> +	oob_ptr = chip->oob_poi;
> +	pl353_nand_write_data_op(mtd, oob_ptr,
> +				 (mtd->oobsize -
> +				 PL353_NAND_LAST_TRANSFER_LENGTH));
> +
> +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
> +	data_phase_addr -= nand_offset;
> +	data_phase_addr |= PL353_NAND_CLEAR_CS;
> +	data_phase_addr |= (1 << END_CMD_VALID_SHIFT);
> +	data_phase_addr += nand_offset;
> +	chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
> +	oob_ptr += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> +	pl353_nand_write_data_op(mtd, oob_ptr, PL353_NAND_LAST_TRANSFER_LENGTH);
> +
> +	/*
> +	 * Apply this short delay always to ensure that we do wait tWB in any
> +	 * case on any machine.
> +	 */
> +	ndelay(100);

Please use sdr timings tWB_min value

> +	nand_wait_ready(mtd);
> +
> +	return 0;
> +}
> +
> +/**
> + * pl353_nand_read_page_hwecc - Hardware ECC based page read function
> + * @mtd:		Pointer to the mtd info structure
> + * @chip:		Pointer to the NAND chip info structure
> + * @buf:		Pointer to the buffer to store read data
> + * @oob_required:	Caller requires OOB data read to chip->oob_poi
> + * @page:		Page number to read
> + *
> + * This functions reads data and checks the data integrity by comparing hardware
> + * generated ECC values and read ECC values from spare area.
> + *
> + * Return:	0 always and updates ECC operation status in to MTD structure
> + */
> +static int pl353_nand_read_page_hwecc(struct mtd_info *mtd,
> +				      struct nand_chip *chip,
> +				      u8 *buf, int oob_required, int page)
> +{
> +	int i, stat, eccsize = chip->ecc.size;
> +	int eccbytes = chip->ecc.bytes;
> +	int eccsteps = chip->ecc.steps;
> +	u8 *p = buf;
> +	u8 *ecc_calc = chip->ecc.calc_buf;
> +	u8 *ecc = chip->ecc.code_buf;
> +	unsigned int max_bitflips = 0;
> +	u8 *oob_ptr;
> +	u32 ret;
> +	unsigned long data_phase_addr;
> +	struct pl353_nand_info *xnfc =
> +		container_of(chip, struct pl353_nand_info, chip);
> +	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
> +
> +	pl353_prepare_cmd(mtd, chip, page, 0, NAND_CMD_READ0,
> +			  NAND_CMD_READSTART, 1);
> +	ndelay(100);

What is this delay for?

> +	pl353_dev_timeout(mtd, chip, 0);
> +
> +	for ( ; (eccsteps - 1); eccsteps--) {
> +		pl353_nand_read_data_op(chip, p, eccsize);
> +		p += eccsize;
> +	}
> +	pl353_nand_read_data_op(chip, p,
> +				(eccsize - PL353_NAND_LAST_TRANSFER_LENGTH));
> +	p += (eccsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> +
> +	/* Set ECC Last bit to 1 */
> +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
> +	data_phase_addr -= nand_offset;
> +	data_phase_addr |= PL353_NAND_ECC_LAST;
> +	data_phase_addr += nand_offset;
> +	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
> +	pl353_nand_read_data_op(chip, p, PL353_NAND_LAST_TRANSFER_LENGTH);
> +
> +	/* Read the calculated ECC value */
> +	p = buf;
> +	chip->ecc.calculate(mtd, p, &ecc_calc[0]);
> +
> +	/* Clear ECC last bit */
> +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
> +	data_phase_addr -= nand_offset;
> +	data_phase_addr &= ~PL353_NAND_ECC_LAST;
> +	data_phase_addr += nand_offset;
> +	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
> +
> +	/* Read the stored ECC value */
> +	oob_ptr = chip->oob_poi;
> +	pl353_nand_read_data_op(chip, oob_ptr,
> +				(mtd->oobsize -
> +				PL353_NAND_LAST_TRANSFER_LENGTH));
> +
> +	/* de-assert chip select */
> +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
> +	data_phase_addr -= nand_offset;
> +	data_phase_addr |= PL353_NAND_CLEAR_CS;
> +	data_phase_addr += nand_offset;
> +	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
> +
> +	oob_ptr += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> +	pl353_nand_read_data_op(chip, oob_ptr, PL353_NAND_LAST_TRANSFER_LENGTH);
> +
> +	ret = mtd_ooblayout_get_eccbytes(mtd, ecc, chip->oob_poi, 0,
> +					 chip->ecc.total);
> +	if (ret)
> +		return ret;
> +
> +	eccsteps = chip->ecc.steps;
> +	p = buf;
> +
> +	/* Check ECC error for all blocks and correct if it is correctable */
> +	for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
> +		stat = chip->ecc.correct(mtd, p, &ecc[i], &ecc_calc[i]);
> +		if (stat < 0) {
> +			mtd->ecc_stats.failed++;
> +		} else {
> +			mtd->ecc_stats.corrected += stat;
> +			max_bitflips = max_t(unsigned int, max_bitflips, stat);
> +		}
> +	}
> +
> +	return max_bitflips;
> +}
> +
> +/**
> + * pl353_nand_select_chip - Select the flash device
> + * @mtd:	Pointer to the mtd info structure
> + * @chip:	Pointer to the NAND chip info structure
> + *
> + * This function is empty as the NAND controller handles chip select line
> + * internally based on the chip address passed in command and data phase.

So why aren't you saving the current chip/die for later use?

> + */
> +static void pl353_nand_select_chip(struct mtd_info *mtd, int chip)
> +{

You should probably save/restore timing registers somewhere now that
you support ->setup_data_interface().

> +}
> +
> +/* NAND framework ->exec_op() hooks and related helpers */
> +static void pl353_nfc_parse_instructions(struct nand_chip *chip,
> +					 const struct nand_subop *subop,
> +					 struct pl353_nfc_op *nfc_op)
> +{
> +	const struct nand_op_instr *instr = NULL;
> +	unsigned int op_id, offset, naddrs;
> +	int i, len;
> +	const u8 *addrs;
> +
> +	memset(nfc_op, 0, sizeof(struct pl353_nfc_op));
> +	for (op_id = 0; op_id < subop->ninstrs; op_id++) {
> +		nfc_op->len = nand_subop_get_data_len(subop, op_id);
> +		len = nand_subop_get_data_len(subop, op_id);
> +		instr = &subop->instrs[op_id];
> +		//if (subop->ninstrs == 1)
> +			//nfc_op->cmnds[0] = -1;
> +		switch (instr->type) {
> +		case NAND_OP_CMD_INSTR:
> +			nfc_op->type = NAND_OP_CMD_INSTR;
> +			if (op_id)
> +				nfc_op->cmnds[1] = instr->ctx.cmd.opcode;
> +			else
> +				nfc_op->cmnds[0] = instr->ctx.cmd.opcode;
> +			nfc_op->cle_ale_delay_ns = instr->delay_ns;
> +			break;
> +
> +		case NAND_OP_ADDR_INSTR:
> +			offset = nand_subop_get_addr_start_off(subop, op_id);
> +			naddrs = nand_subop_get_num_addr_cyc(subop, op_id);
> +			addrs = &instr->ctx.addr.addrs[offset];
> +			nfc_op->addrs = instr->ctx.addr.addrs[offset];
> +			for (i = 0; i < min_t(unsigned int, 4, naddrs); i++) {
> +				nfc_op->addrs |= instr->ctx.addr.addrs[i] <<
> +						 (8 * i);
> +			}
> +
> +			if (naddrs >= 5)
> +				nfc_op->addr5 = addrs[4];
> +			if (naddrs >= 6)
> +				nfc_op->addr6 = addrs[5];
> +			nfc_op->naddrs = nand_subop_get_num_addr_cyc(subop,
> +								     op_id);
> +			nfc_op->cle_ale_delay_ns = instr->delay_ns;
> +			break;
> +
> +		case NAND_OP_DATA_IN_INSTR:
> +			nfc_op->data_instr = instr;
> +			nfc_op->type = NAND_OP_DATA_IN_INSTR;
> +			nfc_op->data_instr_idx = op_id;
> +			nfc_op->data_delay_ns = instr->delay_ns;
> +			break;
> +
> +		case NAND_OP_DATA_OUT_INSTR:
> +			nfc_op->data_instr = instr;
> +			nfc_op->type = NAND_OP_DATA_IN_INSTR;
> +			nfc_op->data_instr_idx = op_id;
> +			nfc_op->data_delay_ns = instr->delay_ns;
> +			break;
> +
> +		case NAND_OP_WAITRDY_INSTR:
> +			nfc_op->rdy_timeout_ms = instr->ctx.waitrdy.timeout_ms;
> +			nfc_op->rdy_delay_ns = instr->delay_ns;
> +			nfc_op->wait = true;
> +			break;
> +		}
> +	}
> +}
> +
> +static void cond_delay(unsigned int ns)
> +{
> +	if (!ns)
> +		return;
> +
> +	if (ns < 10000)
> +		ndelay(ns);
> +	else
> +		udelay(DIV_ROUND_UP(ns, 1000));
> +}
> +
> +/**
> + * pl353_nand_cmd_function - Send command to NAND device
> + * @chip:	Pointer to the NAND chip info structure
> + * @subop:	Pointer to array of instructions
> + * Return:	Always return zero
> + */
> +static int pl353_nand_cmd_function(struct nand_chip *chip,
> +				   const struct nand_subop *subop)
> +{
> +	struct mtd_info *mtd = nand_to_mtd(chip);
> +	const struct nand_op_instr *instr;
> +	struct pl353_nfc_op nfc_op = {};
> +	struct pl353_nand_info *xnfc =
> +		container_of(chip, struct pl353_nand_info, chip);
> +	void __iomem *cmd_addr;
> +	unsigned long cmd_data = 0, end_cmd_valid = 0;
> +	unsigned long cmd_phase_addr, data_phase_addr, end_cmd;
> +	unsigned int op_id, len, offset;
> +	bool reading;
> +
> +	pl353_nfc_parse_instructions(chip, subop, &nfc_op);
> +	instr = nfc_op.data_instr;
> +	op_id = nfc_op.data_instr_idx;
> +	len = nand_subop_get_data_len(subop, op_id);
> +	offset = nand_subop_get_data_start_off(subop, op_id);
> +
> +	pl353_smc_clr_nand_int();
> +	/* Get the command phase address */
> +	if (nfc_op.cmnds[1] != 0) {
> +		if (nfc_op.cmnds[0] == NAND_CMD_SEQIN)
> +			end_cmd_valid = 0;
> +		else
> +			end_cmd_valid = 1;
> +		end_cmd = nfc_op.cmnds[1];
> +	}  else {
> +		end_cmd = 0x0;
> +	}
> +	cmd_phase_addr = (unsigned long __force)xnfc->nand_base +
> +			 ((nfc_op.naddrs << ADDR_CYCLES_SHIFT) |
> +			 (end_cmd_valid << END_CMD_VALID_SHIFT) |
> +			 (COMMAND_PHASE) |
> +			 (end_cmd << END_CMD_SHIFT) |
> +			 (nfc_op.cmnds[0] << START_CMD_SHIFT));
> +
> +	cmd_addr = (void __iomem * __force)cmd_phase_addr;
> +	/* Get the data phase address */
> +	end_cmd_valid = 0;
> +
> +	data_phase_addr = (unsigned long __force)xnfc->nand_base +
> +			  ((0x0 << CLEAR_CS_SHIFT) |
> +			  (end_cmd_valid << END_CMD_VALID_SHIFT) |
> +			  (DATA_PHASE) |
> +			  (end_cmd << END_CMD_SHIFT) |
> +			  (0x0 << ECC_LAST_SHIFT));
> +	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
> +	chip->IO_ADDR_W = chip->IO_ADDR_R;
> +	/* Command phase AXI Read & Write */
> +	if (nfc_op.naddrs >= 5) {
> +		if (mtd->writesize > PL353_NAND_ECC_SIZE) {
> +			cmd_data = nfc_op.addrs;
> +			/* Another address cycle for devices > 128MiB */
> +			if (chip->options & NAND_ROW_ADDR_3) {
> +				writel_relaxed(cmd_data, cmd_addr);
> +				cmd_data = nfc_op.addr5;
> +				if (nfc_op.naddrs >= 6)
> +					cmd_data |= (nfc_op.addr6 << 8);
> +			}
> +		}
> +	}  else {
> +		if (nfc_op.addrs != -1) {
> +			int column = nfc_op.addrs;
> +			/*
> +			 * Change read/write column, read id etc
> +			 * Adjust columns for 16 bit bus width
> +			 */
> +			if ((chip->options & NAND_BUSWIDTH_16) &&
> +			    (nfc_op.cmnds[0] == NAND_CMD_READ0 ||
> +				nfc_op.cmnds[0] == NAND_CMD_SEQIN ||
> +				nfc_op.cmnds[0] == NAND_CMD_RNDOUT ||
> +				nfc_op.cmnds[0] == NAND_CMD_RNDIN)) {
> +				column >>= 1;
> +			}
> +			cmd_data = column;
> +		}
> +	}
> +	writel_relaxed(cmd_data, cmd_addr);
> +	ndelay(100);
> +
> +	cond_delay(nfc_op.cle_ale_delay_ns);
> +	if (!nfc_op.data_instr) {
> +		msleep(nfc_op.rdy_timeout_ms);
> +		cond_delay(nfc_op.rdy_delay_ns);
> +		return 0;
> +	}
> +
> +	reading = (nfc_op.data_instr->type == NAND_OP_DATA_IN_INSTR);
> +
> +	if (!reading) {
> +		if (nfc_op.cmnds[0] == NAND_CMD_SEQIN &&
> +		    nfc_op.cmnds[1] == NAND_CMD_PAGEPROG) {
> +			pl353_nand_write_page_raw(mtd, chip,
> +						  instr->ctx.data.buf.out, 0,
> +						  nfc_op.addrs);
> +		} else {
> +			pl353_nand_write_data_op(mtd, instr->ctx.data.buf.out,
> +						 len);
> +		}
> +		if (nfc_op.rdy_timeout_ms)
> +			pl353_dev_timeout(mtd, chip, nfc_op.rdy_timeout_ms);
> +		cond_delay(nfc_op.rdy_delay_ns);
> +
> +	}
> +
> +	else if (reading) {
> +		if (nfc_op.rdy_timeout_ms)
> +			pl353_dev_timeout(mtd, chip, nfc_op.rdy_timeout_ms);
> +		cond_delay(nfc_op.rdy_delay_ns);
> +		pl353_nand_read_data_op(chip, instr->ctx.data.buf.in, len);
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct nand_op_parser pl353_nfc_op_parser = NAND_OP_PARSER
> +	(NAND_OP_PARSER_PATTERN
> +		(pl353_nand_cmd_function,
> +		NAND_OP_PARSER_PAT_CMD_ELEM(true),
> +		NAND_OP_PARSER_PAT_ADDR_ELEM(true, 7),
> +		NAND_OP_PARSER_PAT_WAITRDY_ELEM(true),
> +		NAND_OP_PARSER_PAT_DATA_IN_ELEM(false, 2048)),
> +	NAND_OP_PARSER_PATTERN
> +		(pl353_nand_cmd_function,
> +		NAND_OP_PARSER_PAT_CMD_ELEM(false),
> +		NAND_OP_PARSER_PAT_ADDR_ELEM(false, 7),
> +		NAND_OP_PARSER_PAT_CMD_ELEM(false),
> +		NAND_OP_PARSER_PAT_WAITRDY_ELEM(false),
> +		NAND_OP_PARSER_PAT_DATA_IN_ELEM(false, 2048)),
> +	NAND_OP_PARSER_PATTERN
> +		(pl353_nand_cmd_function,
> +		NAND_OP_PARSER_PAT_CMD_ELEM(false),
> +		NAND_OP_PARSER_PAT_ADDR_ELEM(true, 7),
> +		NAND_OP_PARSER_PAT_CMD_ELEM(true),
> +		NAND_OP_PARSER_PAT_WAITRDY_ELEM(false)),
> +	NAND_OP_PARSER_PATTERN
> +		(pl353_nand_cmd_function,
> +		NAND_OP_PARSER_PAT_CMD_ELEM(false),
> +		NAND_OP_PARSER_PAT_ADDR_ELEM(false, 8),
> +		NAND_OP_PARSER_PAT_DATA_OUT_ELEM(false, 2048),
> +		NAND_OP_PARSER_PAT_CMD_ELEM(true),
> +		NAND_OP_PARSER_PAT_WAITRDY_ELEM(true)),
> +	NAND_OP_PARSER_PATTERN
> +		(pl353_nand_cmd_function,
> +		NAND_OP_PARSER_PAT_CMD_ELEM(false)),
> +	);
> +
> +static int pl353_nfc_exec_op(struct nand_chip *chip,
> +			     const struct nand_operation *op,
> +			     bool check_only)
> +{
> +	return nand_op_parser_exec_op(chip, &pl353_nfc_op_parser,
> +					      op, check_only);
> +}
> +
> +/**
> + * pl353_nand_device_ready - Check device ready/busy line
> + * @mtd:	Pointer to the mtd_info structure
> + *
> + * Return:	0 on busy or 1 on ready state
> + */
> +static int pl353_nand_device_ready(struct mtd_info *mtd)
> +{
> +	if (pl353_smc_get_nand_int_status_raw()) {
> +		pl353_smc_clr_nand_int();
> +		return 1;
> +	}
> +
> +	return 0;
> +}
> +
> +/**
> + * pl353_nand_ecc_init - Initialize the ecc information as per the ecc mode
> + * @mtd:	Pointer to the mtd_info structure
> + * @ecc:	Pointer to ECC control structure
> + * @ecc_mode:	ondie ecc status
> + *
> + * This function initializes the ecc block and functional pointers as per the
> + * ecc mode
> + */
> +static int pl353_nand_ecc_init(struct mtd_info *mtd, struct nand_ecc_ctrl *ecc,
> +				int ecc_mode)
> +{
> +	struct nand_chip *chip = mtd_to_nand(mtd);
> +	struct pl353_nand_info *xnfc =
> +		container_of(chip, struct pl353_nand_info, chip);
> +	u32 err = 0;
> +
> +	if (ecc_mode == NAND_ECC_ON_DIE) {
> +		pl353_smc_set_ecc_mode(PL353_SMC_ECCMODE_BYPASS);
> +		/*
> +		 * On-Die ECC spare bytes offset 8 is used for ECC codes
> +		 * Use the BBT pattern descriptors
> +		 */
> +		chip->bbt_td = &bbt_main_descr;
> +		chip->bbt_md = &bbt_mirror_descr;
> +		bitmap_set(chip->parameters.get_feature_list,
> +			   ONFI_FEATURE_ON_DIE_ECC, ONFI_FEATURE_ON_DIE_ECC_EN);
> +		bitmap_set(chip->parameters.set_feature_list,
> +			   ONFI_FEATURE_ON_DIE_ECC, ONFI_FEATURE_ON_DIE_ECC_EN);
> +	} else {
> +		ecc->read_oob = pl353_nand_read_oob;
> +		ecc->write_oob = pl353_nand_write_oob;
> +
> +		ecc->mode = NAND_ECC_HW;
> +		/* Hardware ECC generates 3 bytes ECC code for each 512 bytes */
> +		ecc->bytes = 3;
> +		ecc->strength = 1;
> +		ecc->calculate = pl353_nand_calculate_hwecc;
> +		ecc->correct = pl353_nand_correct_data;
> +		ecc->read_page = pl353_nand_read_page_hwecc;
> +		ecc->size = PL353_NAND_ECC_SIZE;
> +		ecc->write_page = pl353_nand_write_page_hwecc;
> +		pl353_smc_set_ecc_pg_size(mtd->writesize);
> +		switch (mtd->writesize) {
> +		case SZ_512:
> +		case SZ_1K:
> +		case SZ_2K:
> +			pl353_smc_set_ecc_mode(PL353_SMC_ECCMODE_APB);
> +			break;
> +		default:
> +			/*
> +			 * The software ECC routines won't work with the
> +			 * SMC controller
> +			 */
> +			ecc->calculate = nand_calculate_ecc;
> +			ecc->correct = nand_correct_data;
> +			ecc->size = 256;
> +			break;
> +		}
> +		if (mtd->writesize <= SZ_512)
> +			xnfc->addr_cycles = 1;
> +		else
> +			xnfc->addr_cycles = 2;
> +
> +		if (chip->options & NAND_ROW_ADDR_3)
> +			xnfc->addr_cycles += 3;
> +		else
> +			xnfc->addr_cycles += 2;
> +
> +		if (mtd->oobsize == 16) {
> +			mtd_set_ooblayout(mtd, &pl353_ecc_ooblayout16_ops);
> +		} else if (mtd->oobsize == 64) {
> +			mtd_set_ooblayout(mtd, &pl353_ecc_ooblayout64_ops);
> +		} else {
> +			err = ENXIO;

Errors are always negative values

> +			dev_err(xnfc->dev, "Unsupported oob Layout\n");
> +		}
> +	}

Space

> +	return err;
> +}
> +static int pl353_setup_data_interface(struct mtd_info *mtd, int csline,
> +				       const struct nand_data_interface *conf)
> +{
> +	struct nand_chip *chip = mtd_to_nand(mtd);
> +	struct pl353_nand_info *xnfc =
> +		container_of(chip, struct pl353_nand_info, chip);
> +	const struct nand_sdr_timings *sdr;
> +	u32 timigs[7], mckperiodps;

s/timigs/timings/

Please use C coding style with '_' instead of a bulk of characters like
mckperiodps.

> +
> +	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
> +		return -EINVAL;

Why?

> +
> +	sdr = nand_get_sdr_timings(conf);
> +	if (IS_ERR(sdr))
> +		return PTR_ERR(sdr);
> +	/*
> +	 * SDR timings are given in pico-seconds while NFC timings must be
> +	 * expressed in NAND controller clock cycles.
> +	 */
> +	mckperiodps = NSEC_PER_SEC / clk_get_rate(xnfc->mclk);
> +	mckperiodps *= 1000;
> +	timigs[0] = DIV_ROUND_UP(sdr->tRC_min, mckperiodps);
> +	timigs[1] = DIV_ROUND_UP(sdr->tWC_min, mckperiodps);
> +	timigs[2] = DIV_ROUND_UP(sdr->tREA_max, mckperiodps);
> +	timigs[3] = DIV_ROUND_UP(sdr->tWP_min, mckperiodps);
> +	timigs[4] = DIV_ROUND_UP(sdr->tCLR_min, mckperiodps);
> +	timigs[5] = DIV_ROUND_UP(sdr->tAR_min, mckperiodps);
> +	timigs[6] = DIV_ROUND_UP(sdr->tRR_min, mckperiodps);
> +	pl353_smc_set_cycles(timigs[0], timigs[1], timigs[2], timigs[3],
> +			     timigs[4], timigs[5], timigs[6]);

You could just give an array of timings instead of 7 values?

This would also simplify the code in the smc driver.

> +
> +	return 0;
> +}
> +/**
> + * pl353_nand_probe - Probe method for the NAND driver
> + * @pdev:	Pointer to the platform_device structure
> + *
> + * This function initializes the driver data structures and the hardware.
> + *
> + * Return:	0 on success or error value on failure
> + */
> +static int pl353_nand_probe(struct platform_device *pdev)
> +{
> +	struct pl353_nand_info *xnfc;
> +	struct mtd_info *mtd;
> +	struct nand_chip *chip;
> +	struct resource *res;
> +	struct device_node *np;
> +	u32 ret;
> +
> +	xnfc = devm_kzalloc(&pdev->dev, sizeof(*xnfc), GFP_KERNEL);
> +	if (!xnfc)
> +		return -ENOMEM;
> +	xnfc->dev = &pdev->dev;
> +	/* Map physical address of NAND flash */
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	xnfc->nand_base = devm_ioremap_resource(xnfc->dev, res);
> +	if (IS_ERR(xnfc->nand_base))
> +		return PTR_ERR(xnfc->nand_base);
> +
> +	chip = &xnfc->chip;
> +	mtd = nand_to_mtd(chip);
> +	chip->exec_op = pl353_nfc_exec_op;
> +	nand_set_controller_data(chip, xnfc);
> +	mtd->priv = chip;
> +	mtd->owner = THIS_MODULE;
> +	if (!mtd->name) {
> +		/*
> +		 * If the new bindings are used and the bootloader has not been
> +		 * updated to pass a new mtdparts parameter on the cmdline, you
> +		 * should define the following property in your NAND node, ie:
> +		 *
> +		 *	label = "pl353-nand";
> +		 *
> +		 * This way, mtd->name will be set by the core when
> +		 * nand_set_flash_node() is called.
> +		 */
> +		mtd->name = devm_kasprintf(xnfc->dev, GFP_KERNEL,
> +					   "%s", PL353_NAND_DRIVER_NAME);
> +		if (!mtd->name) {
> +			dev_err(xnfc->dev, "Failed to allocate mtd->name\n");
> +			return -ENOMEM;
> +		}
> +	}
> +	nand_set_flash_node(chip, xnfc->dev->of_node);
> +
> +	/* Set address of NAND IO lines */
> +	chip->IO_ADDR_R = xnfc->nand_base;
> +	chip->IO_ADDR_W = xnfc->nand_base;
> +	/* Set the driver entry points for MTD */
> +	chip->dev_ready = pl353_nand_device_ready;
> +	chip->select_chip = pl353_nand_select_chip;
> +	/* If we don't set this delay driver sets 20us by default */
> +	np = of_get_next_parent(xnfc->dev->of_node);
> +	xnfc->mclk = of_clk_get(np, 0);
> +	if (IS_ERR(xnfc->mclk)) {
> +		dev_err(xnfc->dev, "Failed to retrieve MCK clk\n");
> +		return PTR_ERR(xnfc->mclk);
> +	}
> +	chip->chip_delay = 30;
> +	/* Set the device option and flash width */
> +	chip->options = NAND_BUSWIDTH_AUTO;
> +	chip->bbt_options = NAND_BBT_USE_FLASH;
> +	platform_set_drvdata(pdev, xnfc);
> +	chip->setup_data_interface = pl353_setup_data_interface;
> +	/* first scan to find the device and get the page size */
> +	if (nand_scan_ident(mtd, 1, NULL)) {
> +		dev_err(xnfc->dev, "nand_scan_ident for NAND failed\n");
> +		return -ENXIO;
> +	}
> +	ret = pl353_nand_ecc_init(mtd, &chip->ecc, chip->ecc.mode);
> +	if (chip->options & NAND_BUSWIDTH_16)
> +		pl353_smc_set_buswidth(PL353_SMC_MEM_WIDTH_16);
> +	/* second phase scan */
> +	if (nand_scan_tail(mtd)) {
> +		dev_err(xnfc->dev, "nand_scan_tail for NAND failed\n");
> +		return -ENXIO;
> +	}
> +
> +	mtd_device_register(mtd, NULL, 0);

Check the returned code

> +
> +	return 0;
> +}
> +
> +/**
> + * pl353_nand_remove - Remove method for the NAND driver
> + * @pdev:	Pointer to the platform_device structure
> + *
> + * This function is called if the driver module is being unloaded. It frees all
> + * resources allocated to the device.
> + *
> + * Return:	0 on success or error value on failure
> + */
> +static int pl353_nand_remove(struct platform_device *pdev)
> +{
> +	struct pl353_nand_info *xnfc = platform_get_drvdata(pdev);
> +	struct mtd_info *mtd = nand_to_mtd(&xnfc->chip);
> +
> +	/* Release resources, unregister device */
> +	nand_release(mtd);

What about MTD core deregistration?

> +
> +	return 0;
> +}
> +
> +/* Match table for device tree binding */
> +static const struct of_device_id pl353_nand_of_match[] = {
> +	{ .compatible = "arm,pl353-nand-r2p1" },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, pl353_nand_of_match);
> +
> +/*
> + * pl353_nand_driver - This structure defines the NAND subsystem platform driver
> + */
> +static struct platform_driver pl353_nand_driver = {
> +	.probe		= pl353_nand_probe,
> +	.remove		= pl353_nand_remove,
> +	.driver		= {
> +		.name	= PL353_NAND_DRIVER_NAME,
> +		.of_match_table = pl353_nand_of_match,
> +	},
> +};
> +
> +module_platform_driver(pl353_nand_driver);
> +
> +MODULE_AUTHOR("Xilinx, Inc.");
> +MODULE_ALIAS("platform:" PL353_NAND_DRIVER_NAME);
> +MODULE_DESCRIPTION("ARM PL353 NAND Flash Driver");
> +MODULE_LICENSE("GPL");

Thanks for your efforts,
Miquèl

RE: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm pl353 smc nand interface

[Naga Sureshkumar Relli]

Hi Miquel,

> -----Original Message-----
> From: Miquel Raynal [mailto:miquel.raynal@bootlin.com]
> Sent: Wednesday, June 27, 2018 8:53 PM
> To: Naga Sureshkumar Relli <nagasure@xilinx.com>
> Cc: boris.brezillon@bootlin.com; richard@nod.at; dwmw2@infradead.org;
> computersforpeace@gmail.com; marek.vasut@gmail.com; f.fainelli@gmail.com;
> mmayer@broadcom.com; rogerq@ti.com; ladis@linux-mips.org; ada@thorsis.com;
> honghui.zhang@mediatek.com; linux-mtd@lists.infradead.org; linux-kernel@vger.kernel.org;
> nagasureshkumarrelli@gmail.com; Michal Simek <michals@xilinx.com>
> Subject: Re: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm
> pl353 smc nand interface
> 
> Hi Naga,
> 
> This is not an issue at all but I think [PATCH vX Y/Z] is a preferred and shorter suffix, you
> can create it automatically by using
> 
>         git format-patch -v X <first_commit>^..<last_commit> --cover-letter
Ok.
> 
> 
> On Thu, 21 Jun 2018 12:12:31 +0530, Naga Sureshkumar Relli
> <naga.sureshkumar.relli@xilinx.com> wrote:
> 
> > Add driver for arm pl353 static memory controller nand interface with
> > HW ECC support. This controller is used in Xilinx Zynq SoC for
> > interfacing the NAND flash memory.
> >
> > Signed-off-by: Naga Sureshkumar Relli
> > <naga.sureshkumar.relli@xilinx.com>
> > ---
> > Changes in 10:
> >  - Typos correction like nand to NAND and soc to SOC etc..
> >  - Defined macros for the values in pl353_nand_calculate_hwecc()
> >  - Modifed ecc_status from int to char in pl353_nand_calculate_hwecc()
> >  - Changed the return type form int to bool to the function
> >    onehot()
> >  - Removed udelay(1000) in pl353_cmd_function, as it is not required
> >  - Dropped ecc->hwctl = NULL in pl353_ecc_init()
> >  - Added an error message in pl353_ecc_init(), when there is no matching
> >    oobsize
> >  - Changed the variable from xnand to xnfc
> >  - Added logic to get mtd->name from DT, if it is specified in DT
> > Changes in v9:
> >  - Addressed the below comments given by Miquel
> >  - instead of using pl353_nand_write32, use directly writel_relaxed
> >  - Fixed check patch warnings
> >  - Renamed write_buf/read_buf to write_data_op/read_data_op
> >  - use BIT macro instead of 1 << nr
> >  - Use NAND_ROW_ADDR_3 flag
> >  - Use nand_wait_ready()
> >  - Removed swecc functions
> >  - Use address cycles as per size, instead of reading it from
> > Parameter page
> >  - Instead of writing too many patterns, use optional property Changes
> > in v8:
> >  - Added exec_op() implementation
> >  - Fixed the below v7 review comments
> >  - removed mtd_info from pl353_nand_info struct
> >  - Corrected ecc layout offsets
> >  - Added on-die ecc support
> > Changes in v7:
> >  - Currently not implemented the memclk rate adjustments. I will
> >    look into this later and once the basic driver is accepted.
> >  - Fixed GPL licence ident
> > Changes in v6:
> >  - Fixed the checkpatch.pl reported warnings
> >  - Using the address cycles information from the onfi param page
> >    earlier it is hardcoded to 5 in driver Changes in v5:
> >  - Configure the nand timing parameters as per the onfi spec Changes in v4:
> >  - Updated the driver to sync with pl353_smc driver APIs Changes in
> > v3:
> >  - implemented the proper error codes
> >  - further breakdown this patch to multiple sets
> >  - added the controller and driver details to Documentation section
> >  - updated the licenece to GPLv2
> >  - reorganized the pl353_nand_ecc_init function Changes in v2:
> >  - use "depends on" rather than "select" option in kconfig
> >  - remove unused variable parts
> > ---
> >  drivers/mtd/nand/raw/Kconfig      |    7 +
> >  drivers/mtd/nand/raw/Makefile     |    1 +
> >  drivers/mtd/nand/raw/pl353_nand.c | 1309
> > +++++++++++++++++++++++++++++++++++++
> >  3 files changed, 1317 insertions(+)
> >  create mode 100644 drivers/mtd/nand/raw/pl353_nand.c
> >
> > diff --git a/drivers/mtd/nand/raw/Kconfig
> > b/drivers/mtd/nand/raw/Kconfig index 6871ff0..1c5d528 100644
> > --- a/drivers/mtd/nand/raw/Kconfig
> > +++ b/drivers/mtd/nand/raw/Kconfig
> > @@ -530,4 +530,11 @@ config MTD_NAND_MTK
> >  	  Enables support for NAND controller on MTK SoCs.
> >  	  This controller is found on mt27xx, mt81xx, mt65xx SoCs.
> >
> > +config MTD_NAND_PL353
> > +	tristate "ARM Pl353 NAND flash driver"
> > +	depends on MTD_NAND && ARM
> > +	depends on PL353_SMC
> > +	help
> > +	  Enables support for PrimeCell Static Memory Controller PL353.
> > +
> >  endif # MTD_NAND
> > diff --git a/drivers/mtd/nand/raw/Makefile
> > b/drivers/mtd/nand/raw/Makefile index 165b7ef..1c702e1 100644
> > --- a/drivers/mtd/nand/raw/Makefile
> > +++ b/drivers/mtd/nand/raw/Makefile
> > @@ -56,6 +56,7 @@ obj-$(CONFIG_MTD_NAND_HISI504)	        +=
> hisi504_nand.o
> >  obj-$(CONFIG_MTD_NAND_BRCMNAND)		+= brcmnand/
> >  obj-$(CONFIG_MTD_NAND_QCOM)		+= qcom_nandc.o
> >  obj-$(CONFIG_MTD_NAND_MTK)		+= mtk_ecc.o mtk_nand.o
> > +obj-$(CONFIG_MTD_NAND_PL353)		+= pl353_nand.o
> >
> >  nand-objs := nand_base.o nand_bbt.o nand_timings.o nand_ids.o
> > nand-objs += nand_amd.o diff --git a/drivers/mtd/nand/raw/pl353_nand.c
> > b/drivers/mtd/nand/raw/pl353_nand.c
> > new file mode 100644
> > index 0000000..3a0acbd
> > --- /dev/null
> > +++ b/drivers/mtd/nand/raw/pl353_nand.c
> > @@ -0,0 +1,1309 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * ARM PL353 NAND flash controller driver
> > + *
> > + * Copyright (C) 2017 Xilinx, Inc
> > + * Author: Punnaiah chowdary kalluri <punnaiah@xilinx.com>
> > + * Author: Naga Sureshkumar Relli <nagasure@xilinx.com>
> > + *
> > + */
> > +
> > +#include <linux/err.h>
> > +#include <linux/delay.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/io.h>
> > +#include <linux/ioport.h>
> > +#include <linux/irq.h>
> > +#include <linux/module.h>
> > +#include <linux/moduleparam.h>
> > +#include <linux/mtd/mtd.h>
> > +#include <linux/mtd/rawnand.h>
> > +#include <linux/mtd/nand_ecc.h>
> > +#include <linux/mtd/partitions.h>
> > +#include <linux/of_address.h>
> > +#include <linux/of_device.h>
> > +#include <linux/of_platform.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/slab.h>
> > +#include <linux/pl353-smc.h>
> > +#include <linux/clk.h>
> > +
> > +#define PL353_NAND_DRIVER_NAME "pl353-nand"
> > +
> > +/* NAND flash driver defines */
> > +#define PL353_NAND_CMD_PHASE	1	/* End command valid in command
> phase */
> > +#define PL353_NAND_DATA_PHASE	2	/* End command valid in data phase
> */
> > +#define PL353_NAND_ECC_SIZE	512	/* Size of data for ECC operation */
> > +
> > +/* Flash memory controller operating parameters */
> > +
> > +#define PL353_NAND_ECC_CONFIG	(BIT(4)  |	/* ECC read at end of page */
> \
> > +				 (0 << 5))	/* No Jumping */
> > +
> > +/* AXI Address definitions */
> > +#define START_CMD_SHIFT		3
> > +#define END_CMD_SHIFT		11
> > +#define END_CMD_VALID_SHIFT	20
> > +#define ADDR_CYCLES_SHIFT	21
> > +#define CLEAR_CS_SHIFT		21
> > +#define ECC_LAST_SHIFT		10
> > +#define COMMAND_PHASE		(0 << 19)
> > +#define DATA_PHASE		BIT(19)
> > +
> > +#define PL353_NAND_ECC_LAST	BIT(ECC_LAST_SHIFT)	/* Set
> ECC_Last */
> > +#define PL353_NAND_CLEAR_CS	BIT(CLEAR_CS_SHIFT)	/* Clear chip
> select */
> > +
> > +#define ONDIE_ECC_FEATURE_ADDR	0x90
> > +#define PL353_NAND_ECC_BUSY_TIMEOUT	(1 * HZ)
> > +#define PL353_NAND_DEV_BUSY_TIMEOUT	(1 * HZ)
> > +#define PL353_NAND_LAST_TRANSFER_LENGTH	4
> > +#define PL353_NAND_ECC_VALID_SHIFT	24
> > +#define PL353_NAND_ECC_VALID_MASK	0x40
> > +
> > +struct pl353_nfc_op {
> > +	u32 cmnds[4];
> > +	u32 thirdrow;
> > +	u32 type;
> > +	u32 end_cmd;
> > +	u32 addrs;
> > +	bool wait;
> > +	u32 len;
> > +	u32 naddrs;
> > +	unsigned int data_instr_idx;
> > +	const struct nand_op_instr *data_instr;
> > +	unsigned int rdy_timeout_ms;
> > +	unsigned int rdy_delay_ns;
> > +	unsigned int data_delay_ns;
> > +	unsigned int cle_ale_delay_ns;
> > +	u32 addr5;
> > +	u32 addr6;
> > +};
> > +
> > +/**
> > + * struct pl353_nand_info - Defines the NAND flash driver instance
> > + * @chip:		NAND chip information structure
> > + * @nand_base:		Virtual address of the NAND flash device
> > + * @end_cmd_pending:	End command is pending
> > + * @end_cmd:		End command
> > + * @row_addr_cycles:	Row address cycles
> > + * @col_addr_cycles:	Column address cycles
> > + * @address:		Page address
> > + * @cmd_pending:	More command is needed
> 
> I'm still not ok with this structure.
> 
> The NAND controller entries must be separated from the NAND chip's. You can get some
> inspiration from marvell_nand.c or sunxi_nand.c.
Ok, Will check that.
> 
> > + */
> > +struct pl353_nand_info {
> > +	struct nand_chip chip;
> > +	struct device *dev;
> > +	void __iomem *nand_base;
> > +	unsigned long end_cmd_pending;
> > +	unsigned long end_cmd;
> > +	u8 addr_cycles;
> > +	u32 address;
> > +	u32 cmd_pending;
> > +	struct completion complete;
> > +	struct clk *mclk;
> > +
> 
> Extra space
Ok, will correct it.
> 
> > +};
> > +
> > +static int pl353_ecc_ooblayout16_ecc(struct mtd_info *mtd, int section,
> > +				     struct mtd_oob_region *oobregion) {
> > +	struct nand_chip *chip = mtd_to_nand(mtd);
> > +
> > +	if (section >= chip->ecc.steps)
> > +		return -ERANGE;
> > +
> > +	oobregion->offset = (section * chip->ecc.bytes);
> > +	oobregion->length = chip->ecc.bytes;
> > +
> > +	return 0;
> > +}
> > +
> > +static int pl353_ecc_ooblayout16_free(struct mtd_info *mtd, int section,
> > +				      struct mtd_oob_region *oobregion) {
> > +	struct nand_chip *chip = mtd_to_nand(mtd);
> > +
> > +	if (section >= chip->ecc.steps)
> > +		return -ERANGE;
> > +
> > +	oobregion->offset = (section * chip->ecc.bytes) + 8;
> > +	oobregion->length = 8;
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct mtd_ooblayout_ops pl353_ecc_ooblayout16_ops = {
> > +	.ecc = pl353_ecc_ooblayout16_ecc,
> > +	.free = pl353_ecc_ooblayout16_free,
> > +};
> > +
> > +static int pl353_ecc_ooblayout64_ecc(struct mtd_info *mtd, int section,
> > +				     struct mtd_oob_region *oobregion) {
> > +	struct nand_chip *chip = mtd_to_nand(mtd);
> > +
> > +	if (section >= chip->ecc.steps)
> > +		return -ERANGE;
> > +
> > +	oobregion->offset = (section * chip->ecc.bytes) + 52;
> > +	oobregion->length = chip->ecc.bytes;
> > +
> > +	return 0;
> > +}
> > +
> > +static int pl353_ecc_ooblayout64_free(struct mtd_info *mtd, int section,
> > +				      struct mtd_oob_region *oobregion) {
> > +	struct nand_chip *chip = mtd_to_nand(mtd);
> > +
> > +	if (section)
> > +		return -ERANGE;
> > +
> > +	if (section >= chip->ecc.steps)
> > +		return -ERANGE;
> > +
> > +	oobregion->offset = (section * chip->ecc.bytes) + 2;
> > +	oobregion->length = 50;
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct mtd_ooblayout_ops pl353_ecc_ooblayout64_ops = {
> > +	.ecc = pl353_ecc_ooblayout64_ecc,
> > +	.free = pl353_ecc_ooblayout64_free,
> > +};
> > +
> > +/* Generic flash bbt decriptors */
> > +static u8 bbt_pattern[] = { 'B', 'b', 't', '0' }; static u8
> > +mirror_pattern[] = { '1', 't', 'b', 'B' };
> > +
> > +static struct nand_bbt_descr bbt_main_descr = {
> > +	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE |
> NAND_BBT_WRITE
> > +		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
> > +	.offs = 4,
> > +	.len = 4,
> > +	.veroffs = 20,
> > +	.maxblocks = 4,
> > +	.pattern = bbt_pattern
> > +};
> > +
> > +static struct nand_bbt_descr bbt_mirror_descr = {
> > +	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE |
> NAND_BBT_WRITE
> > +		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
> > +	.offs = 4,
> > +	.len = 4,
> > +	.veroffs = 20,
> > +	.maxblocks = 4,
> > +	.pattern = mirror_pattern
> > +};
> > +
> > +/**
> > + * pl353_nand_read_data_op - read chip data into buffer
> > + * @chip:	Pointer to the NAND chip info structure
> > + * @in:		Pointer to the buffer to store read data
> > + * @len:	Number of bytes to read
> > + * Return:	Always return zero
> > + */
> > +static int pl353_nand_read_data_op(struct nand_chip *chip,
> > +				   u8 *in,
> > +				   unsigned int len)
> > +{
> > +	int i;
> > +
> > +	if (IS_ALIGNED((uint32_t)in, sizeof(uint32_t)) &&
> > +	    IS_ALIGNED(len, sizeof(uint32_t))) {
> > +		u32 *ptr = (u32 *)in;
> > +
> > +		len /= 4;
> > +		for (i = 0; i < len; i++)
> > +			ptr[i] = readl(chip->IO_ADDR_R);
> 
> Please do not use IO_ADDR_R/W, these chip structure entries are deprecated and might be
> removed anytime soon. Removing them will simplify a lot all the functions where you do kind
> of unreadable pointer operations around these value. This is really bad and I already told you
> about it.
> 
Ok, sorry for that, I will update it.
> Please fix this and then I'll review the rest.
Sure.
> 
> > +	} else {
> > +		for (i = 0; i < len; i++)
> > +			in[i] = readb(chip->IO_ADDR_R);
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +/**
> > + * pl353_nand_write_buf - write buffer to chip
> > + * @mtd:	Pointer to the mtd info structure
> > + * @buf:	Pointer to the buffer to store write data
> > + * @len:	Number of bytes to write
> > + */
> > +static void pl353_nand_write_data_op(struct mtd_info *mtd, const u8 *buf,
> > +				     int len)
> > +{
> > +	int i;
> > +	struct nand_chip *chip = mtd_to_nand(mtd);
> > +
> > +	if (IS_ALIGNED((uint32_t)buf, sizeof(uint32_t)) &&
> > +	    IS_ALIGNED(len, sizeof(uint32_t))) {
> > +		u32 *ptr = (u32 *)buf;
> > +
> > +		len /= 4;
> > +		for (i = 0; i < len; i++)
> > +			writel(ptr[i], chip->IO_ADDR_W);
> > +	} else {
> > +		for (i = 0; i < len; i++)
> > +			writeb(buf[i], chip->IO_ADDR_W);
> > +	}
> > +}
> > +
> > +/**
> > + * pl353_nand_calculate_hwecc - Calculate Hardware ECC
> > + * @mtd:	Pointer to the mtd_info structure
> > + * @data:	Pointer to the page data
> > + * @ecc:	Pointer to the ECC buffer where ECC data needs to be stored
> > + *
> > + * This function retrieves the Hardware ECC data from the controller
> > +and returns
> > + * ECC data back to the MTD subsystem.
> > + *
> > + * Return:	0 on success or error value on failure
> > + */
> > +static int pl353_nand_calculate_hwecc(struct mtd_info *mtd,
> > +				      const u8 *data, u8 *ecc)
> > +{
> > +	u32 ecc_value;
> > +	u8 ecc_reg, ecc_byte, ecc_status;
> > +	unsigned long timeout = jiffies + PL353_NAND_ECC_BUSY_TIMEOUT;
> 
> New line
Ok. I will correct it.
> 
> > +	/* Wait till the ECC operation is complete or timeout */
> > +	do {
> > +		if (pl353_smc_ecc_is_busy())
> > +			cpu_relax();
> > +		else
> > +			break;
> > +	} while (!time_after_eq(jiffies, timeout));
> > +
> > +	if (time_after_eq(jiffies, timeout)) {
> > +		pr_err("%s timed out\n", __func__);
> > +		return -ETIMEDOUT;
> > +	}
> > +
> > +	for (ecc_reg = 0; ecc_reg < 4; ecc_reg++) {
> > +		/* Read ECC value for each block */
> > +		ecc_value = pl353_smc_get_ecc_val(ecc_reg);
> > +		ecc_status = (ecc_value >> PL353_NAND_ECC_VALID_SHIFT);
> > +		/* ECC value valid */
> > +		if (ecc_status & PL353_NAND_ECC_VALID_MASK) {
> > +			for (ecc_byte = 0; ecc_byte < 3; ecc_byte++) {
> > +				/* Copy ECC bytes to MTD buffer */
> > +				*ecc = ~ecc_value & 0xFF;
> > +				ecc_value = ecc_value >> 8;
> > +				ecc++;
> > +			}
> > +		} else {
> > +			pr_warn("%s status failed\n", __func__);
> > +			return -1;
> > +		}
> > +	}
> 
> New line
Ok. I will remove it.
> 
> > +	return 0;
> > +}
> > +
> > +/**
> > + * onehot - onehot function
> > + * @value:	Value to check for onehot
> > + *
> > + * This function checks whether a value is onehot or not.
> > + * onehot is if and only if onebit is set.
> > + *
> > + * Return:	1 if it is onehot else 0
> > + */
> > +static bool onehot(unsigned short value) {
> > +	return (value & (value - 1)) == 0;
> 
> Please use something from bitmap.c or bitops.h to do this.
Ok.
> 
> > +}
> > +
> > +/**
> > + * pl353_nand_correct_data - ECC correction function
> > + * @mtd:	Pointer to the mtd_info structure
> > + * @buf:	Pointer to the page data
> > + * @read_ecc:	Pointer to the ECC value read from spare data area
> > + * @calc_ecc:	Pointer to the calculated ECC value
> > + *
> > + * This function corrects the ECC single bit errors & detects 2-bit errors.
> > + *
> > + * Return:	0 if no ECC errors found
> > + *		1 if single bit error found and corrected.
> > + *		-1 if multiple uncorrectable ECC errors found.
> > + */
> > +static int pl353_nand_correct_data(struct mtd_info *mtd, unsigned char *buf,
> > +				   unsigned char *read_ecc,
> > +				   unsigned char *calc_ecc)
> > +{
> > +	unsigned char bit_addr;
> > +	unsigned int byte_addr;
> > +	unsigned short ecc_odd, ecc_even, read_ecc_lower, read_ecc_upper;
> > +	unsigned short calc_ecc_lower, calc_ecc_upper;
> > +
> > +	read_ecc_lower = (read_ecc[0] | (read_ecc[1] << 8)) & 0xfff;
> > +	read_ecc_upper = ((read_ecc[1] >> 4) | (read_ecc[2] << 4)) & 0xfff;
> > +
> > +	calc_ecc_lower = (calc_ecc[0] | (calc_ecc[1] << 8)) & 0xfff;
> > +	calc_ecc_upper = ((calc_ecc[1] >> 4) | (calc_ecc[2] << 4)) & 0xfff;
> > +
> > +	ecc_odd = read_ecc_lower ^ calc_ecc_lower;
> > +	ecc_even = read_ecc_upper ^ calc_ecc_upper;
> > +
> > +	/* no error */
> > +	if (!ecc_odd && !ecc_even)
> > +		return 0;
> > +
> > +	if (ecc_odd == (~ecc_even & 0xfff)) {
> > +		/* bits [11:3] of error code is byte offset */
> > +		byte_addr = (ecc_odd >> 3) & 0x1ff;
> 
> You might want to define these values.
Ok
> 
> > +		/* bits [2:0] of error code is bit offset */
> > +		bit_addr = ecc_odd & 0x7;
> 
> Same here.
Ok
> 
> > +		/* Toggling error bit */
> > +		buf[byte_addr] ^= (BIT(bit_addr));
> > +		return 1;
> > +	}
> 
> New line
Ok. I will correct it.
> 
> > +	/* one error in parity */
> > +	if (onehot(ecc_odd | ecc_even) == 1)
> > +		return 1;
> > +
> > +	/* Uncorrectable error */
> > +	return -1;
> > +}
> > +
> > +static int pl353_dev_timeout(struct mtd_info *mtd, struct nand_chip *chip,
> > +			     unsigned long timeout)
> > +{
> > +	if (timeout)
> > +		timeout = jiffies + msecs_to_jiffies(timeout);
> > +	else
> > +		timeout = jiffies + PL353_NAND_DEV_BUSY_TIMEOUT;
> > +
> > +	do {
> > +		if (chip->dev_ready(mtd))
> > +			break;
> > +		cpu_relax();
> > +	} while (!time_after_eq(jiffies, timeout));
> 
> Isn't this a nand_wait_ready() equivalent?
Let me check.
> 
> > +
> > +	if (time_after_eq(jiffies, timeout)) {
> > +		pr_err("%s timed out\n", __func__);
> > +		return -1;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static void pl353_prepare_cmd(struct mtd_info *mtd, struct nand_chip *chip,
> > +			      int page, int column, int start_cmd, int end_cmd,
> > +			      bool read)
> > +{
> > +	unsigned long data_phase_addr;
> > +	u32 end_cmd_valid = 0;
> > +	void __iomem *cmd_addr;
> > +	unsigned long cmd_phase_addr = 0, cmd_data = 0;
> > +
> > +	struct pl353_nand_info *xnfc =
> > +		container_of(chip, struct pl353_nand_info, chip);
> > +
> > +	end_cmd_valid = read ? 1 : 0;
> > +
> > +	cmd_phase_addr = (unsigned long __force)xnfc->nand_base +
> > +			 ((xnfc->addr_cycles
> > +			 << ADDR_CYCLES_SHIFT) |
> > +			 (end_cmd_valid << END_CMD_VALID_SHIFT) |
> > +			 (COMMAND_PHASE) |
> > +			 (end_cmd << END_CMD_SHIFT) |
> > +			 (start_cmd << START_CMD_SHIFT));
> > +	cmd_addr = (void __iomem * __force)cmd_phase_addr;
> > +
> > +	/* Get the data phase address */
> > +	data_phase_addr = (unsigned long __force)xnfc->nand_base +
> > +			  ((0x0 << CLEAR_CS_SHIFT) |
> > +			  (0 << END_CMD_VALID_SHIFT) |
> > +			  (DATA_PHASE) |
> > +			  (end_cmd << END_CMD_SHIFT) |
> > +			  (0x0 << ECC_LAST_SHIFT));
> > +
> > +	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
> > +	chip->IO_ADDR_W = chip->IO_ADDR_R;
> > +	if (chip->options & NAND_BUSWIDTH_16)
> > +		column /= 2;
> > +	cmd_data = column;
> > +	if (mtd->writesize > PL353_NAND_ECC_SIZE) {
> > +		cmd_data |= page << 16;
> > +		/* Another address cycle for devices > 128MiB */
> > +		if (chip->options & NAND_ROW_ADDR_3) {
> > +			writel_relaxed(cmd_data, cmd_addr);
> > +			cmd_data = (page >> 16);
> > +		}
> > +	} else {
> > +		cmd_data |= page << 8;
> > +	}
> > +
> > +	writel_relaxed(cmd_data, cmd_addr);
> > +}
> > +
> > +/**
> > + * pl353_nand_read_oob - [REPLACEABLE] the most common OOB data read function
> > + * @mtd:	Pointer to the mtd info structure
> > + * @chip:	Pointer to the NAND chip info structure
> > + * @page:	Page number to read
> > + *
> > + * Return:	Always return zero
> > + */
> > +static int pl353_nand_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
> > +			       int page)
> > +{
> > +	unsigned long data_phase_addr;
> > +	u8 *p;
> > +	struct pl353_nand_info *xnfc =
> > +		container_of(chip, struct pl353_nand_info, chip);
> > +	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
> > +
> > +	chip->pagebuf = -1;
> > +	if (mtd->writesize < PL353_NAND_ECC_SIZE)
> > +		return 0;
> > +
> > +	pl353_prepare_cmd(mtd, chip, page, mtd->writesize, NAND_CMD_READ0,
> > +			  NAND_CMD_READSTART, 1);
> > +
> > +	ndelay(100);
> > +	pl353_dev_timeout(mtd, chip, 0);
> > +
> > +	p = chip->oob_poi;
> > +	pl353_nand_read_data_op(chip, p,
> > +				(mtd->oobsize -
> > +				PL353_NAND_LAST_TRANSFER_LENGTH));
> > +	p += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> > +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
> > +	data_phase_addr -= nand_offset;
> > +	data_phase_addr |= PL353_NAND_CLEAR_CS;
> > +	data_phase_addr += nand_offset;
> > +	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
> > +	pl353_nand_read_data_op(chip, p, PL353_NAND_LAST_TRANSFER_LENGTH);
> > +
> > +	return 0;
> > +}
> > +
> > +/**
> > + * pl353_nand_write_oob - [REPLACEABLE] the most common OOB data write
> function
> > + * @mtd:	Pointer to the mtd info structure
> > + * @chip:	Pointer to the NAND chip info structure
> > + * @page:	Page number to write
> > + *
> > + * Return:	Zero on success and EIO on failure
> > + */
> > +static int pl353_nand_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
> > +				int page)
> > +{
> > +	const u8 *buf = chip->oob_poi;
> > +	unsigned long data_phase_addr;
> > +	struct pl353_nand_info *xnfc =
> > +		container_of(chip, struct pl353_nand_info, chip);
> > +	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
> > +	u32 addrcycles = 0;
> > +
> > +	chip->pagebuf = -1;
> > +	addrcycles = xnfc->addr_cycles;
> > +	pl353_prepare_cmd(mtd, chip, page, mtd->writesize, NAND_CMD_SEQIN,
> > +			  NAND_CMD_PAGEPROG, 0);
> > +	ndelay(100);
> > +	pl353_nand_write_data_op(mtd, buf,
> > +				 (mtd->oobsize -
> > +				 PL353_NAND_LAST_TRANSFER_LENGTH));
> > +	buf += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> > +
> > +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
> > +	data_phase_addr -= nand_offset;
> > +	data_phase_addr |= PL353_NAND_CLEAR_CS;
> > +	data_phase_addr |= (1 << END_CMD_VALID_SHIFT);
> > +	data_phase_addr += nand_offset;
> > +	chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
> > +	pl353_nand_write_data_op(mtd, buf,
> PL353_NAND_LAST_TRANSFER_LENGTH);
> > +	nand_wait_ready(mtd);
> > +
> > +	return 0;
> > +}
> > +
> > +/**
> > + * pl353_nand_read_page_raw - [Intern] read raw page data without ecc
> > + * @mtd:		Pointer to the mtd info structure
> > + * @chip:		Pointer to the NAND chip info structure
> > + * @buf:		Pointer to the data buffer
> > + * @oob_required:	Caller requires OOB data read to chip->oob_poi
> > + * @page:		Page number to read
> > + *
> > + * Return:	Always return zero
> > + */
> > +static int pl353_nand_read_page_raw(struct mtd_info *mtd,
> > +				    struct nand_chip *chip,
> > +				    u8 *buf, int oob_required, int page) {
> > +	unsigned long data_phase_addr;
> > +	u8 *p;
> > +	struct pl353_nand_info *xnfc =
> > +		container_of(chip, struct pl353_nand_info, chip);
> > +	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
> > +
> > +	pl353_nand_read_data_op(chip, buf, mtd->writesize);
> > +	p = chip->oob_poi;
> > +	pl353_nand_read_data_op(chip, p,
> > +				(mtd->oobsize -
> > +				PL353_NAND_LAST_TRANSFER_LENGTH));
> > +	p += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> > +
> > +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
> > +	data_phase_addr -= nand_offset;
> > +	data_phase_addr |= PL353_NAND_CLEAR_CS;
> > +	data_phase_addr += nand_offset;
> > +	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
> > +
> > +	pl353_nand_read_data_op(chip, p, PL353_NAND_LAST_TRANSFER_LENGTH);
> > +
> > +	return 0;
> > +}
> > +
> > +/**
> > + * pl353_nand_write_page_raw - [Intern] raw page write function
> > + * @mtd:		Pointer to the mtd info structure
> > + * @chip:		Pointer to the NAND chip info structure
> > + * @buf:		Pointer to the data buffer
> > + * @oob_required:	Caller requires OOB data read to chip->oob_poi
> > + * @page:		Page number to write
> > + *
> > + * Return:	Always return zero
> > + */
> > +static int pl353_nand_write_page_raw(struct mtd_info *mtd,
> > +				     struct nand_chip *chip,
> > +				     const u8 *buf, int oob_required,
> > +				     int page)
> > +{
> > +	unsigned long data_phase_addr;
> > +	u8 *p;
> > +
> > +	struct pl353_nand_info *xnfc =
> > +		container_of(chip, struct pl353_nand_info, chip);
> > +	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
> > +
> > +	pl353_nand_write_data_op(mtd, buf, mtd->writesize);
> > +	p = chip->oob_poi;
> > +	pl353_nand_write_data_op(mtd, p,
> > +				 (mtd->oobsize -
> > +				 PL353_NAND_LAST_TRANSFER_LENGTH));
> > +	p += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> > +
> > +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
> > +	data_phase_addr -= nand_offset;
> > +	data_phase_addr |= PL353_NAND_CLEAR_CS;
> > +	data_phase_addr |= (1 << END_CMD_VALID_SHIFT);
> > +	data_phase_addr += nand_offset;
> > +	chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
> > +
> > +	pl353_nand_write_data_op(mtd, p, PL353_NAND_LAST_TRANSFER_LENGTH);
> > +
> > +	return 0;
> > +}
> > +
> > +/**
> > + * nand_write_page_hwecc - Hardware ECC based page write function
> > + * @mtd:		Pointer to the mtd info structure
> > + * @chip:		Pointer to the NAND chip info structure
> > + * @buf:		Pointer to the data buffer
> > + * @oob_required:	Caller requires OOB data read to chip->oob_poi
> > + * @page:		Page number to write
> > + *
> > + * This functions writes data and hardware generated ECC values in to the page.
> > + *
> > + * Return:	Always return zero
> > + */
> > +static int pl353_nand_write_page_hwecc(struct mtd_info *mtd,
> > +				       struct nand_chip *chip,
> > +				       const u8 *buf, int oob_required,
> > +				       int page)
> > +{
> > +	int eccsize = chip->ecc.size;
> > +	int eccsteps = chip->ecc.steps;
> > +	u8 *ecc_calc = chip->ecc.calc_buf;
> > +	u8 *oob_ptr;
> > +	const u8 *p = buf;
> > +	u32 ret;
> > +	unsigned long data_phase_addr;
> > +	struct pl353_nand_info *xnfc =
> > +		container_of(chip, struct pl353_nand_info, chip);
> > +	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
> > +
> > +	pl353_prepare_cmd(mtd, chip, page, 0, NAND_CMD_SEQIN,
> > +			  NAND_CMD_PAGEPROG, 0);
> > +	ndelay(100);
> > +	for ( ; (eccsteps - 1); eccsteps--) {
> > +		pl353_nand_write_data_op(mtd, p, eccsize);
> > +		p += eccsize;
> > +	}
> > +	pl353_nand_write_data_op(mtd, p,
> > +				 (eccsize - PL353_NAND_LAST_TRANSFER_LENGTH));
> > +	p += (eccsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> > +
> > +	/* Set ECC Last bit to 1 */
> > +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
> > +	data_phase_addr -= nand_offset;
> > +	data_phase_addr |= PL353_NAND_ECC_LAST;
> > +	data_phase_addr += nand_offset;
> > +	chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
> > +	pl353_nand_write_data_op(mtd, p, PL353_NAND_LAST_TRANSFER_LENGTH);
> > +
> > +	p = buf;
> > +	chip->ecc.calculate(mtd, p, &ecc_calc[0]);
> > +
> > +	/* Wait for ECC to be calculated and read the error values */
> > +	ret = mtd_ooblayout_set_eccbytes(mtd, ecc_calc, chip->oob_poi,
> > +					 0, chip->ecc.total);
> > +	if (ret)
> > +		return ret;
> > +	/* Clear ECC last bit */
> > +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
> > +	data_phase_addr -= nand_offset;
> > +	data_phase_addr &= ~PL353_NAND_ECC_LAST;
> > +	data_phase_addr += nand_offset;
> > +	chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
> > +
> > +	/* Write the spare area with ECC bytes */
> > +	oob_ptr = chip->oob_poi;
> > +	pl353_nand_write_data_op(mtd, oob_ptr,
> > +				 (mtd->oobsize -
> > +				 PL353_NAND_LAST_TRANSFER_LENGTH));
> > +
> > +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_W;
> > +	data_phase_addr -= nand_offset;
> > +	data_phase_addr |= PL353_NAND_CLEAR_CS;
> > +	data_phase_addr |= (1 << END_CMD_VALID_SHIFT);
> > +	data_phase_addr += nand_offset;
> > +	chip->IO_ADDR_W = (void __iomem * __force)data_phase_addr;
> > +	oob_ptr += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> > +	pl353_nand_write_data_op(mtd, oob_ptr,
> > +PL353_NAND_LAST_TRANSFER_LENGTH);
> > +
> > +	/*
> > +	 * Apply this short delay always to ensure that we do wait tWB in any
> > +	 * case on any machine.
> > +	 */
> > +	ndelay(100);
> 
> Please use sdr timings tWB_min value
Ok.
> 
> > +	nand_wait_ready(mtd);
> > +
> > +	return 0;
> > +}
> > +
> > +/**
> > + * pl353_nand_read_page_hwecc - Hardware ECC based page read function
> > + * @mtd:		Pointer to the mtd info structure
> > + * @chip:		Pointer to the NAND chip info structure
> > + * @buf:		Pointer to the buffer to store read data
> > + * @oob_required:	Caller requires OOB data read to chip->oob_poi
> > + * @page:		Page number to read
> > + *
> > + * This functions reads data and checks the data integrity by
> > +comparing hardware
> > + * generated ECC values and read ECC values from spare area.
> > + *
> > + * Return:	0 always and updates ECC operation status in to MTD structure
> > + */
> > +static int pl353_nand_read_page_hwecc(struct mtd_info *mtd,
> > +				      struct nand_chip *chip,
> > +				      u8 *buf, int oob_required, int page) {
> > +	int i, stat, eccsize = chip->ecc.size;
> > +	int eccbytes = chip->ecc.bytes;
> > +	int eccsteps = chip->ecc.steps;
> > +	u8 *p = buf;
> > +	u8 *ecc_calc = chip->ecc.calc_buf;
> > +	u8 *ecc = chip->ecc.code_buf;
> > +	unsigned int max_bitflips = 0;
> > +	u8 *oob_ptr;
> > +	u32 ret;
> > +	unsigned long data_phase_addr;
> > +	struct pl353_nand_info *xnfc =
> > +		container_of(chip, struct pl353_nand_info, chip);
> > +	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
> > +
> > +	pl353_prepare_cmd(mtd, chip, page, 0, NAND_CMD_READ0,
> > +			  NAND_CMD_READSTART, 1);
> > +	ndelay(100);
> 
> What is this delay for?
We have seen failures with out this delay, with older code.
But i will check this by removing this delay, in this new driver.
> 
> > +	pl353_dev_timeout(mtd, chip, 0);
> > +
> > +	for ( ; (eccsteps - 1); eccsteps--) {
> > +		pl353_nand_read_data_op(chip, p, eccsize);
> > +		p += eccsize;
> > +	}
> > +	pl353_nand_read_data_op(chip, p,
> > +				(eccsize - PL353_NAND_LAST_TRANSFER_LENGTH));
> > +	p += (eccsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> > +
> > +	/* Set ECC Last bit to 1 */
> > +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
> > +	data_phase_addr -= nand_offset;
> > +	data_phase_addr |= PL353_NAND_ECC_LAST;
> > +	data_phase_addr += nand_offset;
> > +	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
> > +	pl353_nand_read_data_op(chip, p, PL353_NAND_LAST_TRANSFER_LENGTH);
> > +
> > +	/* Read the calculated ECC value */
> > +	p = buf;
> > +	chip->ecc.calculate(mtd, p, &ecc_calc[0]);
> > +
> > +	/* Clear ECC last bit */
> > +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
> > +	data_phase_addr -= nand_offset;
> > +	data_phase_addr &= ~PL353_NAND_ECC_LAST;
> > +	data_phase_addr += nand_offset;
> > +	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
> > +
> > +	/* Read the stored ECC value */
> > +	oob_ptr = chip->oob_poi;
> > +	pl353_nand_read_data_op(chip, oob_ptr,
> > +				(mtd->oobsize -
> > +				PL353_NAND_LAST_TRANSFER_LENGTH));
> > +
> > +	/* de-assert chip select */
> > +	data_phase_addr = (unsigned long __force)chip->IO_ADDR_R;
> > +	data_phase_addr -= nand_offset;
> > +	data_phase_addr |= PL353_NAND_CLEAR_CS;
> > +	data_phase_addr += nand_offset;
> > +	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
> > +
> > +	oob_ptr += (mtd->oobsize - PL353_NAND_LAST_TRANSFER_LENGTH);
> > +	pl353_nand_read_data_op(chip, oob_ptr,
> > +PL353_NAND_LAST_TRANSFER_LENGTH);
> > +
> > +	ret = mtd_ooblayout_get_eccbytes(mtd, ecc, chip->oob_poi, 0,
> > +					 chip->ecc.total);
> > +	if (ret)
> > +		return ret;
> > +
> > +	eccsteps = chip->ecc.steps;
> > +	p = buf;
> > +
> > +	/* Check ECC error for all blocks and correct if it is correctable */
> > +	for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
> > +		stat = chip->ecc.correct(mtd, p, &ecc[i], &ecc_calc[i]);
> > +		if (stat < 0) {
> > +			mtd->ecc_stats.failed++;
> > +		} else {
> > +			mtd->ecc_stats.corrected += stat;
> > +			max_bitflips = max_t(unsigned int, max_bitflips, stat);
> > +		}
> > +	}
> > +
> > +	return max_bitflips;
> > +}
> > +
> > +/**
> > + * pl353_nand_select_chip - Select the flash device
> > + * @mtd:	Pointer to the mtd info structure
> > + * @chip:	Pointer to the NAND chip info structure
> > + *
> > + * This function is empty as the NAND controller handles chip select
> > +line
> > + * internally based on the chip address passed in command and data phase.
> 
> So why aren't you saving the current chip/die for later use?
> 
> > + */
> > +static void pl353_nand_select_chip(struct mtd_info *mtd, int chip) {
> 
> You should probably save/restore timing registers somewhere now that you support -
> >setup_data_interface().
Ok, let me try this.
> 
> > +}
> > +
> > +/* NAND framework ->exec_op() hooks and related helpers */ static
> > +void pl353_nfc_parse_instructions(struct nand_chip *chip,
> > +					 const struct nand_subop *subop,
> > +					 struct pl353_nfc_op *nfc_op)
> > +{
> > +	const struct nand_op_instr *instr = NULL;
> > +	unsigned int op_id, offset, naddrs;
> > +	int i, len;
> > +	const u8 *addrs;
> > +
> > +	memset(nfc_op, 0, sizeof(struct pl353_nfc_op));
> > +	for (op_id = 0; op_id < subop->ninstrs; op_id++) {
> > +		nfc_op->len = nand_subop_get_data_len(subop, op_id);
> > +		len = nand_subop_get_data_len(subop, op_id);
> > +		instr = &subop->instrs[op_id];
> > +		//if (subop->ninstrs == 1)
> > +			//nfc_op->cmnds[0] = -1;
> > +		switch (instr->type) {
> > +		case NAND_OP_CMD_INSTR:
> > +			nfc_op->type = NAND_OP_CMD_INSTR;
> > +			if (op_id)
> > +				nfc_op->cmnds[1] = instr->ctx.cmd.opcode;
> > +			else
> > +				nfc_op->cmnds[0] = instr->ctx.cmd.opcode;
> > +			nfc_op->cle_ale_delay_ns = instr->delay_ns;
> > +			break;
> > +
> > +		case NAND_OP_ADDR_INSTR:
> > +			offset = nand_subop_get_addr_start_off(subop, op_id);
> > +			naddrs = nand_subop_get_num_addr_cyc(subop, op_id);
> > +			addrs = &instr->ctx.addr.addrs[offset];
> > +			nfc_op->addrs = instr->ctx.addr.addrs[offset];
> > +			for (i = 0; i < min_t(unsigned int, 4, naddrs); i++) {
> > +				nfc_op->addrs |= instr->ctx.addr.addrs[i] <<
> > +						 (8 * i);
> > +			}
> > +
> > +			if (naddrs >= 5)
> > +				nfc_op->addr5 = addrs[4];
> > +			if (naddrs >= 6)
> > +				nfc_op->addr6 = addrs[5];
> > +			nfc_op->naddrs = nand_subop_get_num_addr_cyc(subop,
> > +								     op_id);
> > +			nfc_op->cle_ale_delay_ns = instr->delay_ns;
> > +			break;
> > +
> > +		case NAND_OP_DATA_IN_INSTR:
> > +			nfc_op->data_instr = instr;
> > +			nfc_op->type = NAND_OP_DATA_IN_INSTR;
> > +			nfc_op->data_instr_idx = op_id;
> > +			nfc_op->data_delay_ns = instr->delay_ns;
> > +			break;
> > +
> > +		case NAND_OP_DATA_OUT_INSTR:
> > +			nfc_op->data_instr = instr;
> > +			nfc_op->type = NAND_OP_DATA_IN_INSTR;
> > +			nfc_op->data_instr_idx = op_id;
> > +			nfc_op->data_delay_ns = instr->delay_ns;
> > +			break;
> > +
> > +		case NAND_OP_WAITRDY_INSTR:
> > +			nfc_op->rdy_timeout_ms = instr->ctx.waitrdy.timeout_ms;
> > +			nfc_op->rdy_delay_ns = instr->delay_ns;
> > +			nfc_op->wait = true;
> > +			break;
> > +		}
> > +	}
> > +}
> > +
> > +static void cond_delay(unsigned int ns) {
> > +	if (!ns)
> > +		return;
> > +
> > +	if (ns < 10000)
> > +		ndelay(ns);
> > +	else
> > +		udelay(DIV_ROUND_UP(ns, 1000));
> > +}
> > +
> > +/**
> > + * pl353_nand_cmd_function - Send command to NAND device
> > + * @chip:	Pointer to the NAND chip info structure
> > + * @subop:	Pointer to array of instructions
> > + * Return:	Always return zero
> > + */
> > +static int pl353_nand_cmd_function(struct nand_chip *chip,
> > +				   const struct nand_subop *subop) {
> > +	struct mtd_info *mtd = nand_to_mtd(chip);
> > +	const struct nand_op_instr *instr;
> > +	struct pl353_nfc_op nfc_op = {};
> > +	struct pl353_nand_info *xnfc =
> > +		container_of(chip, struct pl353_nand_info, chip);
> > +	void __iomem *cmd_addr;
> > +	unsigned long cmd_data = 0, end_cmd_valid = 0;
> > +	unsigned long cmd_phase_addr, data_phase_addr, end_cmd;
> > +	unsigned int op_id, len, offset;
> > +	bool reading;
> > +
> > +	pl353_nfc_parse_instructions(chip, subop, &nfc_op);
> > +	instr = nfc_op.data_instr;
> > +	op_id = nfc_op.data_instr_idx;
> > +	len = nand_subop_get_data_len(subop, op_id);
> > +	offset = nand_subop_get_data_start_off(subop, op_id);
> > +
> > +	pl353_smc_clr_nand_int();
> > +	/* Get the command phase address */
> > +	if (nfc_op.cmnds[1] != 0) {
> > +		if (nfc_op.cmnds[0] == NAND_CMD_SEQIN)
> > +			end_cmd_valid = 0;
> > +		else
> > +			end_cmd_valid = 1;
> > +		end_cmd = nfc_op.cmnds[1];
> > +	}  else {
> > +		end_cmd = 0x0;
> > +	}
> > +	cmd_phase_addr = (unsigned long __force)xnfc->nand_base +
> > +			 ((nfc_op.naddrs << ADDR_CYCLES_SHIFT) |
> > +			 (end_cmd_valid << END_CMD_VALID_SHIFT) |
> > +			 (COMMAND_PHASE) |
> > +			 (end_cmd << END_CMD_SHIFT) |
> > +			 (nfc_op.cmnds[0] << START_CMD_SHIFT));
> > +
> > +	cmd_addr = (void __iomem * __force)cmd_phase_addr;
> > +	/* Get the data phase address */
> > +	end_cmd_valid = 0;
> > +
> > +	data_phase_addr = (unsigned long __force)xnfc->nand_base +
> > +			  ((0x0 << CLEAR_CS_SHIFT) |
> > +			  (end_cmd_valid << END_CMD_VALID_SHIFT) |
> > +			  (DATA_PHASE) |
> > +			  (end_cmd << END_CMD_SHIFT) |
> > +			  (0x0 << ECC_LAST_SHIFT));
> > +	chip->IO_ADDR_R = (void __iomem * __force)data_phase_addr;
> > +	chip->IO_ADDR_W = chip->IO_ADDR_R;
> > +	/* Command phase AXI Read & Write */
> > +	if (nfc_op.naddrs >= 5) {
> > +		if (mtd->writesize > PL353_NAND_ECC_SIZE) {
> > +			cmd_data = nfc_op.addrs;
> > +			/* Another address cycle for devices > 128MiB */
> > +			if (chip->options & NAND_ROW_ADDR_3) {
> > +				writel_relaxed(cmd_data, cmd_addr);
> > +				cmd_data = nfc_op.addr5;
> > +				if (nfc_op.naddrs >= 6)
> > +					cmd_data |= (nfc_op.addr6 << 8);
> > +			}
> > +		}
> > +	}  else {
> > +		if (nfc_op.addrs != -1) {
> > +			int column = nfc_op.addrs;
> > +			/*
> > +			 * Change read/write column, read id etc
> > +			 * Adjust columns for 16 bit bus width
> > +			 */
> > +			if ((chip->options & NAND_BUSWIDTH_16) &&
> > +			    (nfc_op.cmnds[0] == NAND_CMD_READ0 ||
> > +				nfc_op.cmnds[0] == NAND_CMD_SEQIN ||
> > +				nfc_op.cmnds[0] == NAND_CMD_RNDOUT ||
> > +				nfc_op.cmnds[0] == NAND_CMD_RNDIN)) {
> > +				column >>= 1;
> > +			}
> > +			cmd_data = column;
> > +		}
> > +	}
> > +	writel_relaxed(cmd_data, cmd_addr);
> > +	ndelay(100);
> > +
> > +	cond_delay(nfc_op.cle_ale_delay_ns);
> > +	if (!nfc_op.data_instr) {
> > +		msleep(nfc_op.rdy_timeout_ms);
> > +		cond_delay(nfc_op.rdy_delay_ns);
> > +		return 0;
> > +	}
> > +
> > +	reading = (nfc_op.data_instr->type == NAND_OP_DATA_IN_INSTR);
> > +
> > +	if (!reading) {
> > +		if (nfc_op.cmnds[0] == NAND_CMD_SEQIN &&
> > +		    nfc_op.cmnds[1] == NAND_CMD_PAGEPROG) {
> > +			pl353_nand_write_page_raw(mtd, chip,
> > +						  instr->ctx.data.buf.out, 0,
> > +						  nfc_op.addrs);
> > +		} else {
> > +			pl353_nand_write_data_op(mtd, instr->ctx.data.buf.out,
> > +						 len);
> > +		}
> > +		if (nfc_op.rdy_timeout_ms)
> > +			pl353_dev_timeout(mtd, chip, nfc_op.rdy_timeout_ms);
> > +		cond_delay(nfc_op.rdy_delay_ns);
> > +
> > +	}
> > +
> > +	else if (reading) {
> > +		if (nfc_op.rdy_timeout_ms)
> > +			pl353_dev_timeout(mtd, chip, nfc_op.rdy_timeout_ms);
> > +		cond_delay(nfc_op.rdy_delay_ns);
> > +		pl353_nand_read_data_op(chip, instr->ctx.data.buf.in, len);
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct nand_op_parser pl353_nfc_op_parser = NAND_OP_PARSER
> > +	(NAND_OP_PARSER_PATTERN
> > +		(pl353_nand_cmd_function,
> > +		NAND_OP_PARSER_PAT_CMD_ELEM(true),
> > +		NAND_OP_PARSER_PAT_ADDR_ELEM(true, 7),
> > +		NAND_OP_PARSER_PAT_WAITRDY_ELEM(true),
> > +		NAND_OP_PARSER_PAT_DATA_IN_ELEM(false, 2048)),
> > +	NAND_OP_PARSER_PATTERN
> > +		(pl353_nand_cmd_function,
> > +		NAND_OP_PARSER_PAT_CMD_ELEM(false),
> > +		NAND_OP_PARSER_PAT_ADDR_ELEM(false, 7),
> > +		NAND_OP_PARSER_PAT_CMD_ELEM(false),
> > +		NAND_OP_PARSER_PAT_WAITRDY_ELEM(false),
> > +		NAND_OP_PARSER_PAT_DATA_IN_ELEM(false, 2048)),
> > +	NAND_OP_PARSER_PATTERN
> > +		(pl353_nand_cmd_function,
> > +		NAND_OP_PARSER_PAT_CMD_ELEM(false),
> > +		NAND_OP_PARSER_PAT_ADDR_ELEM(true, 7),
> > +		NAND_OP_PARSER_PAT_CMD_ELEM(true),
> > +		NAND_OP_PARSER_PAT_WAITRDY_ELEM(false)),
> > +	NAND_OP_PARSER_PATTERN
> > +		(pl353_nand_cmd_function,
> > +		NAND_OP_PARSER_PAT_CMD_ELEM(false),
> > +		NAND_OP_PARSER_PAT_ADDR_ELEM(false, 8),
> > +		NAND_OP_PARSER_PAT_DATA_OUT_ELEM(false, 2048),
> > +		NAND_OP_PARSER_PAT_CMD_ELEM(true),
> > +		NAND_OP_PARSER_PAT_WAITRDY_ELEM(true)),
> > +	NAND_OP_PARSER_PATTERN
> > +		(pl353_nand_cmd_function,
> > +		NAND_OP_PARSER_PAT_CMD_ELEM(false)),
> > +	);
> > +
> > +static int pl353_nfc_exec_op(struct nand_chip *chip,
> > +			     const struct nand_operation *op,
> > +			     bool check_only)
> > +{
> > +	return nand_op_parser_exec_op(chip, &pl353_nfc_op_parser,
> > +					      op, check_only);
> > +}
> > +
> > +/**
> > + * pl353_nand_device_ready - Check device ready/busy line
> > + * @mtd:	Pointer to the mtd_info structure
> > + *
> > + * Return:	0 on busy or 1 on ready state
> > + */
> > +static int pl353_nand_device_ready(struct mtd_info *mtd) {
> > +	if (pl353_smc_get_nand_int_status_raw()) {
> > +		pl353_smc_clr_nand_int();
> > +		return 1;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +/**
> > + * pl353_nand_ecc_init - Initialize the ecc information as per the ecc mode
> > + * @mtd:	Pointer to the mtd_info structure
> > + * @ecc:	Pointer to ECC control structure
> > + * @ecc_mode:	ondie ecc status
> > + *
> > + * This function initializes the ecc block and functional pointers as
> > +per the
> > + * ecc mode
> > + */
> > +static int pl353_nand_ecc_init(struct mtd_info *mtd, struct nand_ecc_ctrl *ecc,
> > +				int ecc_mode)
> > +{
> > +	struct nand_chip *chip = mtd_to_nand(mtd);
> > +	struct pl353_nand_info *xnfc =
> > +		container_of(chip, struct pl353_nand_info, chip);
> > +	u32 err = 0;
> > +
> > +	if (ecc_mode == NAND_ECC_ON_DIE) {
> > +		pl353_smc_set_ecc_mode(PL353_SMC_ECCMODE_BYPASS);
> > +		/*
> > +		 * On-Die ECC spare bytes offset 8 is used for ECC codes
> > +		 * Use the BBT pattern descriptors
> > +		 */
> > +		chip->bbt_td = &bbt_main_descr;
> > +		chip->bbt_md = &bbt_mirror_descr;
> > +		bitmap_set(chip->parameters.get_feature_list,
> > +			   ONFI_FEATURE_ON_DIE_ECC,
> ONFI_FEATURE_ON_DIE_ECC_EN);
> > +		bitmap_set(chip->parameters.set_feature_list,
> > +			   ONFI_FEATURE_ON_DIE_ECC,
> ONFI_FEATURE_ON_DIE_ECC_EN);
> > +	} else {
> > +		ecc->read_oob = pl353_nand_read_oob;
> > +		ecc->write_oob = pl353_nand_write_oob;
> > +
> > +		ecc->mode = NAND_ECC_HW;
> > +		/* Hardware ECC generates 3 bytes ECC code for each 512 bytes */
> > +		ecc->bytes = 3;
> > +		ecc->strength = 1;
> > +		ecc->calculate = pl353_nand_calculate_hwecc;
> > +		ecc->correct = pl353_nand_correct_data;
> > +		ecc->read_page = pl353_nand_read_page_hwecc;
> > +		ecc->size = PL353_NAND_ECC_SIZE;
> > +		ecc->write_page = pl353_nand_write_page_hwecc;
> > +		pl353_smc_set_ecc_pg_size(mtd->writesize);
> > +		switch (mtd->writesize) {
> > +		case SZ_512:
> > +		case SZ_1K:
> > +		case SZ_2K:
> > +			pl353_smc_set_ecc_mode(PL353_SMC_ECCMODE_APB);
> > +			break;
> > +		default:
> > +			/*
> > +			 * The software ECC routines won't work with the
> > +			 * SMC controller
> > +			 */
> > +			ecc->calculate = nand_calculate_ecc;
> > +			ecc->correct = nand_correct_data;
> > +			ecc->size = 256;
> > +			break;
> > +		}
> > +		if (mtd->writesize <= SZ_512)
> > +			xnfc->addr_cycles = 1;
> > +		else
> > +			xnfc->addr_cycles = 2;
> > +
> > +		if (chip->options & NAND_ROW_ADDR_3)
> > +			xnfc->addr_cycles += 3;
> > +		else
> > +			xnfc->addr_cycles += 2;
> > +
> > +		if (mtd->oobsize == 16) {
> > +			mtd_set_ooblayout(mtd, &pl353_ecc_ooblayout16_ops);
> > +		} else if (mtd->oobsize == 64) {
> > +			mtd_set_ooblayout(mtd, &pl353_ecc_ooblayout64_ops);
> > +		} else {
> > +			err = ENXIO;
> 
> Errors are always negative values
Ok, will update.
> 
> > +			dev_err(xnfc->dev, "Unsupported oob Layout\n");
> > +		}
> > +	}
> 
> Space
Ok.
> 
> > +	return err;
> > +}
> > +static int pl353_setup_data_interface(struct mtd_info *mtd, int csline,
> > +				       const struct nand_data_interface *conf) {
> > +	struct nand_chip *chip = mtd_to_nand(mtd);
> > +	struct pl353_nand_info *xnfc =
> > +		container_of(chip, struct pl353_nand_info, chip);
> > +	const struct nand_sdr_timings *sdr;
> > +	u32 timigs[7], mckperiodps;
> 
> s/timigs/timings/
Ok will correct it.
> 
> Please use C coding style with '_' instead of a bulk of characters like mckperiodps.
Ok.
> 
> > +
> > +	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
> > +		return -EINVAL;
> 
> Why?
It is similar to 
if (chipnr < 0)
	return 0;
hence written like that.
Also if I didn't do that, then probe is failing.
Am I missing some thing?
> 
> > +
> > +	sdr = nand_get_sdr_timings(conf);
> > +	if (IS_ERR(sdr))
> > +		return PTR_ERR(sdr);
> > +	/*
> > +	 * SDR timings are given in pico-seconds while NFC timings must be
> > +	 * expressed in NAND controller clock cycles.
> > +	 */
> > +	mckperiodps = NSEC_PER_SEC / clk_get_rate(xnfc->mclk);
> > +	mckperiodps *= 1000;
> > +	timigs[0] = DIV_ROUND_UP(sdr->tRC_min, mckperiodps);
> > +	timigs[1] = DIV_ROUND_UP(sdr->tWC_min, mckperiodps);
> > +	timigs[2] = DIV_ROUND_UP(sdr->tREA_max, mckperiodps);
> > +	timigs[3] = DIV_ROUND_UP(sdr->tWP_min, mckperiodps);
> > +	timigs[4] = DIV_ROUND_UP(sdr->tCLR_min, mckperiodps);
> > +	timigs[5] = DIV_ROUND_UP(sdr->tAR_min, mckperiodps);
> > +	timigs[6] = DIV_ROUND_UP(sdr->tRR_min, mckperiodps);
> > +	pl353_smc_set_cycles(timigs[0], timigs[1], timigs[2], timigs[3],
> > +			     timigs[4], timigs[5], timigs[6]);
> 
> You could just give an array of timings instead of 7 values?
Yes, I will update it.
> 
> This would also simplify the code in the smc driver.
Yes.
> 
> > +
> > +	return 0;
> > +}
> > +/**
> > + * pl353_nand_probe - Probe method for the NAND driver
> > + * @pdev:	Pointer to the platform_device structure
> > + *
> > + * This function initializes the driver data structures and the hardware.
> > + *
> > + * Return:	0 on success or error value on failure
> > + */
> > +static int pl353_nand_probe(struct platform_device *pdev) {
> > +	struct pl353_nand_info *xnfc;
> > +	struct mtd_info *mtd;
> > +	struct nand_chip *chip;
> > +	struct resource *res;
> > +	struct device_node *np;
> > +	u32 ret;
> > +
> > +	xnfc = devm_kzalloc(&pdev->dev, sizeof(*xnfc), GFP_KERNEL);
> > +	if (!xnfc)
> > +		return -ENOMEM;
> > +	xnfc->dev = &pdev->dev;
> > +	/* Map physical address of NAND flash */
> > +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +	xnfc->nand_base = devm_ioremap_resource(xnfc->dev, res);
> > +	if (IS_ERR(xnfc->nand_base))
> > +		return PTR_ERR(xnfc->nand_base);
> > +
> > +	chip = &xnfc->chip;
> > +	mtd = nand_to_mtd(chip);
> > +	chip->exec_op = pl353_nfc_exec_op;
> > +	nand_set_controller_data(chip, xnfc);
> > +	mtd->priv = chip;
> > +	mtd->owner = THIS_MODULE;
> > +	if (!mtd->name) {
> > +		/*
> > +		 * If the new bindings are used and the bootloader has not been
> > +		 * updated to pass a new mtdparts parameter on the cmdline, you
> > +		 * should define the following property in your NAND node, ie:
> > +		 *
> > +		 *	label = "pl353-nand";
> > +		 *
> > +		 * This way, mtd->name will be set by the core when
> > +		 * nand_set_flash_node() is called.
> > +		 */
> > +		mtd->name = devm_kasprintf(xnfc->dev, GFP_KERNEL,
> > +					   "%s", PL353_NAND_DRIVER_NAME);
> > +		if (!mtd->name) {
> > +			dev_err(xnfc->dev, "Failed to allocate mtd->name\n");
> > +			return -ENOMEM;
> > +		}
> > +	}
> > +	nand_set_flash_node(chip, xnfc->dev->of_node);
> > +
> > +	/* Set address of NAND IO lines */
> > +	chip->IO_ADDR_R = xnfc->nand_base;
> > +	chip->IO_ADDR_W = xnfc->nand_base;
> > +	/* Set the driver entry points for MTD */
> > +	chip->dev_ready = pl353_nand_device_ready;
> > +	chip->select_chip = pl353_nand_select_chip;
> > +	/* If we don't set this delay driver sets 20us by default */
> > +	np = of_get_next_parent(xnfc->dev->of_node);
> > +	xnfc->mclk = of_clk_get(np, 0);
> > +	if (IS_ERR(xnfc->mclk)) {
> > +		dev_err(xnfc->dev, "Failed to retrieve MCK clk\n");
> > +		return PTR_ERR(xnfc->mclk);
> > +	}
> > +	chip->chip_delay = 30;
> > +	/* Set the device option and flash width */
> > +	chip->options = NAND_BUSWIDTH_AUTO;
> > +	chip->bbt_options = NAND_BBT_USE_FLASH;
> > +	platform_set_drvdata(pdev, xnfc);
> > +	chip->setup_data_interface = pl353_setup_data_interface;
> > +	/* first scan to find the device and get the page size */
> > +	if (nand_scan_ident(mtd, 1, NULL)) {
> > +		dev_err(xnfc->dev, "nand_scan_ident for NAND failed\n");
> > +		return -ENXIO;
> > +	}
> > +	ret = pl353_nand_ecc_init(mtd, &chip->ecc, chip->ecc.mode);
> > +	if (chip->options & NAND_BUSWIDTH_16)
> > +		pl353_smc_set_buswidth(PL353_SMC_MEM_WIDTH_16);
> > +	/* second phase scan */
> > +	if (nand_scan_tail(mtd)) {
> > +		dev_err(xnfc->dev, "nand_scan_tail for NAND failed\n");
> > +		return -ENXIO;
> > +	}
> > +
> > +	mtd_device_register(mtd, NULL, 0);
> 
> Check the returned code
Ok.
> 
> > +
> > +	return 0;
> > +}
> > +
> > +/**
> > + * pl353_nand_remove - Remove method for the NAND driver
> > + * @pdev:	Pointer to the platform_device structure
> > + *
> > + * This function is called if the driver module is being unloaded. It
> > +frees all
> > + * resources allocated to the device.
> > + *
> > + * Return:	0 on success or error value on failure
> > + */
> > +static int pl353_nand_remove(struct platform_device *pdev) {
> > +	struct pl353_nand_info *xnfc = platform_get_drvdata(pdev);
> > +	struct mtd_info *mtd = nand_to_mtd(&xnfc->chip);
> > +
> > +	/* Release resources, unregister device */
> > +	nand_release(mtd);
> 
> What about MTD core deregistration?
nand_release(), it self will do that.
> 
> > +
> > +	return 0;
> > +}
> > +
> > +/* Match table for device tree binding */ static const struct
> > +of_device_id pl353_nand_of_match[] = {
> > +	{ .compatible = "arm,pl353-nand-r2p1" },
> > +	{},
> > +};
> > +MODULE_DEVICE_TABLE(of, pl353_nand_of_match);
> > +
> > +/*
> > + * pl353_nand_driver - This structure defines the NAND subsystem
> > +platform driver  */ static struct platform_driver pl353_nand_driver =
> > +{
> > +	.probe		= pl353_nand_probe,
> > +	.remove		= pl353_nand_remove,
> > +	.driver		= {
> > +		.name	= PL353_NAND_DRIVER_NAME,
> > +		.of_match_table = pl353_nand_of_match,
> > +	},
> > +};
> > +
> > +module_platform_driver(pl353_nand_driver);
> > +
> > +MODULE_AUTHOR("Xilinx, Inc.");
> > +MODULE_ALIAS("platform:" PL353_NAND_DRIVER_NAME);
> > +MODULE_DESCRIPTION("ARM PL353 NAND Flash Driver");
> > +MODULE_LICENSE("GPL");
> 
> Thanks for your efforts,
> Miquèl

Thanks for the review.

Regards,
Naga Sureshkumar Relli.

Re: [[LINUX PATCH v10] 2/4] memory: pl353: Add driver for arm pl353 static memory controller

[Linus Walleij]

On Thu, Jun 21, 2018 at 8:43 AM Naga Sureshkumar Relli
<naga.sureshkumar.relli@xilinx.com> wrote:

> Add driver for arm pl353 static memory controller. This controller is used in
> Xilinx Zynq SoC for interfacing the NAND and NOR/SRAM memory devices.
>
> Signed-off-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>

(...)

> +config PL353_SMC
> +       tristate "ARM PL35X Static Memory Controller(SMC) driver"
> +       default y
> +       depends on ARM
> +       depends on ARCH_ZYNQ

depends on ARM_AMBA

> +#include <linux/platform_device.h>

This is a PrimeCell with the ARM primecell ID registers
specified, so it should not use platform device.

Use <linux/amba/bus.h>

It further needs to match on these magic values (found in
0xfe0 etc) and use the name "apb_pclk" for the peripheral
(silicon) clock.

See examples such as:
drivers/mmc/host/mmci.c
drivers/tty/serial/amba-pl011.c
drivers/video/fbdev/amba-clcd.c
drivers/hwtracing/coresight/*
etc for examples.

Also see and reference the special PrimeCell DT bindings:
Documentation/devicetree/bindings/arm/primecell.txt

Yours,
Linus Walleij

Re: [[LINUX PATCH v10] 1/4] Devicetree: Add pl353 smc controller devicetree binding information

[Linus Walleij]

On Thu, Jun 21, 2018 at 8:43 AM Naga Sureshkumar Relli
<naga.sureshkumar.relli@xilinx.com> wrote:

Thanks for your patch!

> Add pl353 static memory controller devicetree binding information.
>
> Signed-off-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
> +Device tree bindings for ARM PL353 static memory controller
> +
> +PL353 static memory controller supports two kinds of memory
> +interfaces.i.e NAND and SRAM/NOR interfaces.
> +The actual devices are instantiated from the child nodes of pl353 smc node.

See and reference the special PrimeCell DT bindings:
Documentation/devicetree/bindings/arm/primecell.txt

> +Required properties:
> +- compatible           : Must be "arm,pl353-smc-r2p1"

Should be:

"arm,pl353-smc-r2p1", "arm,primecell";

It will be possible for the Linux AMBA core to probe the device
from just reading out the primecell ID registers, so the first
compatible string will not even be used by many OS:es.

> +- reg                  : Controller registers map and length.
> +- clock-names          : List of input clock names - "ref_clk", "aper_clk"
> +                         (See clock bindings for details).

The AMBA primecell peripheral clock (clocking the silicon)
must be named "apb_pclk".

> +- clocks               : Clock phandles (see clock bindings for details).
> +- address-cells                : Must be 1.
> +- size-cells           : Must be 1.
> +
> +Child nodes:
> + For NAND the "arm,pl353-nand-r2p1" and for NOR the "cfi-flash" drivers are
> +supported as child nodes.
> +
> +for NAND partition information please refer the below file
> +Documentation/devicetree/bindings/mtd/partition.txt
> +
> +Example:
> +       smcc: memory-controller@e000e000
> +                       compatible = "arm,pl353-smc-r2p1"

Add , "arm,primecell";

> +                       clock-names = "memclk", "aclk";

This doesn't even have the same name as in the bindings
above, I think the latter should be named "apb_pclk".

Otherwise it looks good!

Yours,
Linus Walleij

Re: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm pl353 smc nand interface

[Miquel Raynal]

Hi Naga,

> > > +/**
> > > + * pl353_nand_read_page_hwecc - Hardware ECC based page read function
> > > + * @mtd:		Pointer to the mtd info structure
> > > + * @chip:		Pointer to the NAND chip info structure
> > > + * @buf:		Pointer to the buffer to store read data
> > > + * @oob_required:	Caller requires OOB data read to chip->oob_poi
> > > + * @page:		Page number to read
> > > + *
> > > + * This functions reads data and checks the data integrity by
> > > +comparing hardware
> > > + * generated ECC values and read ECC values from spare area.
> > > + *
> > > + * Return:	0 always and updates ECC operation status in to MTD structure
> > > + */
> > > +static int pl353_nand_read_page_hwecc(struct mtd_info *mtd,
> > > +				      struct nand_chip *chip,
> > > +				      u8 *buf, int oob_required, int page) {
> > > +	int i, stat, eccsize = chip->ecc.size;
> > > +	int eccbytes = chip->ecc.bytes;
> > > +	int eccsteps = chip->ecc.steps;
> > > +	u8 *p = buf;
> > > +	u8 *ecc_calc = chip->ecc.calc_buf;
> > > +	u8 *ecc = chip->ecc.code_buf;
> > > +	unsigned int max_bitflips = 0;
> > > +	u8 *oob_ptr;
> > > +	u32 ret;
> > > +	unsigned long data_phase_addr;
> > > +	struct pl353_nand_info *xnfc =
> > > +		container_of(chip, struct pl353_nand_info, chip);
> > > +	unsigned long nand_offset = (unsigned long __force)xnfc->nand_base;
> > > +
> > > +	pl353_prepare_cmd(mtd, chip, page, 0, NAND_CMD_READ0,
> > > +			  NAND_CMD_READSTART, 1);
> > > +	ndelay(100);  
> > 
> > What is this delay for?  
> We have seen failures with out this delay, with older code.
> But i will check this by removing this delay, in this new driver.

Please check all of them. We should get rid of random delays like that.
Either there is something to poll, or there is a specific value to use
(you can get them from the SDR interface structure).

[...]

> > > +
> > > +	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
> > > +		return -EINVAL;  
> > 
> > Why?  
> It is similar to 
> if (chipnr < 0)
> 	return 0;

Mmmmmh, no?

(return 0) != (return -EINVAL)

The core is asking you to check if the controller driver support
particular timings (usually ONFI modes 1-5). Returning an error means
"I only support the slowest timings" which, I suppose, is wrong. Please
fix this and compare the speeds.

> hence written like that.
> Also if I didn't do that, then probe is failing.
> Am I missing some thing?
> >   

[...]

> > > +/**
> > > + * pl353_nand_probe - Probe method for the NAND driver
> > > + * @pdev:	Pointer to the platform_device structure
> > > + *
> > > + * This function initializes the driver data structures and the hardware.
> > > + *
> > > + * Return:	0 on success or error value on failure
> > > + */
> > > +static int pl353_nand_probe(struct platform_device *pdev) {
> > > +	struct pl353_nand_info *xnfc;
> > > +	struct mtd_info *mtd;
> > > +	struct nand_chip *chip;
> > > +	struct resource *res;
> > > +	struct device_node *np;
> > > +	u32 ret;
> > > +
> > > +	xnfc = devm_kzalloc(&pdev->dev, sizeof(*xnfc), GFP_KERNEL);
> > > +	if (!xnfc)
> > > +		return -ENOMEM;
> > > +	xnfc->dev = &pdev->dev;
> > > +	/* Map physical address of NAND flash */
> > > +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > +	xnfc->nand_base = devm_ioremap_resource(xnfc->dev, res);
> > > +	if (IS_ERR(xnfc->nand_base))
> > > +		return PTR_ERR(xnfc->nand_base);
> > > +
> > > +	chip = &xnfc->chip;
> > > +	mtd = nand_to_mtd(chip);
> > > +	chip->exec_op = pl353_nfc_exec_op;
> > > +	nand_set_controller_data(chip, xnfc);
> > > +	mtd->priv = chip;
> > > +	mtd->owner = THIS_MODULE;
> > > +	if (!mtd->name) {
> > > +		/*
> > > +		 * If the new bindings are used and the bootloader has not been
> > > +		 * updated to pass a new mtdparts parameter on the cmdline, you
> > > +		 * should define the following property in your NAND node, ie:
> > > +		 *
> > > +		 *	label = "pl353-nand";
> > > +		 *
> > > +		 * This way, mtd->name will be set by the core when
> > > +		 * nand_set_flash_node() is called.
> > > +		 */
> > > +		mtd->name = devm_kasprintf(xnfc->dev, GFP_KERNEL,
> > > +					   "%s", PL353_NAND_DRIVER_NAME);
> > > +		if (!mtd->name) {
> > > +			dev_err(xnfc->dev, "Failed to allocate mtd->name\n");
> > > +			return -ENOMEM;
> > > +		}
> > > +	}
> > > +	nand_set_flash_node(chip, xnfc->dev->of_node);
> > > +
> > > +	/* Set address of NAND IO lines */
> > > +	chip->IO_ADDR_R = xnfc->nand_base;
> > > +	chip->IO_ADDR_W = xnfc->nand_base;
> > > +	/* Set the driver entry points for MTD */
> > > +	chip->dev_ready = pl353_nand_device_ready;
> > > +	chip->select_chip = pl353_nand_select_chip;
> > > +	/* If we don't set this delay driver sets 20us by default */
> > > +	np = of_get_next_parent(xnfc->dev->of_node);
> > > +	xnfc->mclk = of_clk_get(np, 0);
> > > +	if (IS_ERR(xnfc->mclk)) {
> > > +		dev_err(xnfc->dev, "Failed to retrieve MCK clk\n");
> > > +		return PTR_ERR(xnfc->mclk);
> > > +	}
> > > +	chip->chip_delay = 30;
> > > +	/* Set the device option and flash width */
> > > +	chip->options = NAND_BUSWIDTH_AUTO;
> > > +	chip->bbt_options = NAND_BBT_USE_FLASH;
> > > +	platform_set_drvdata(pdev, xnfc);
> > > +	chip->setup_data_interface = pl353_setup_data_interface;
> > > +	/* first scan to find the device and get the page size */
> > > +	if (nand_scan_ident(mtd, 1, NULL)) {
> > > +		dev_err(xnfc->dev, "nand_scan_ident for NAND failed\n");
> > > +		return -ENXIO;
> > > +	}

Space here

> > > +	ret = pl353_nand_ecc_init(mtd, &chip->ecc, chip->ecc.mode);

ret should be checked

> > > +	if (chip->options & NAND_BUSWIDTH_16)
> > > +		pl353_smc_set_buswidth(PL353_SMC_MEM_WIDTH_16);

Space

> > > +	/* second phase scan */
> > > +	if (nand_scan_tail(mtd)) {
> > > +		dev_err(xnfc->dev, "nand_scan_tail for NAND failed\n");
> > > +		return -ENXIO;
> > > +	}
> > > +
> > > +	mtd_device_register(mtd, NULL, 0);  
> > 
> > Check the returned code  
> Ok.

And if it returns an error, please call nand_cleanup().

> >   
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +/**
> > > + * pl353_nand_remove - Remove method for the NAND driver
> > > + * @pdev:	Pointer to the platform_device structure
> > > + *
> > > + * This function is called if the driver module is being unloaded. It
> > > +frees all
> > > + * resources allocated to the device.
> > > + *
> > > + * Return:	0 on success or error value on failure
> > > + */
> > > +static int pl353_nand_remove(struct platform_device *pdev) {
> > > +	struct pl353_nand_info *xnfc = platform_get_drvdata(pdev);
> > > +	struct mtd_info *mtd = nand_to_mtd(&xnfc->chip);
> > > +
> > > +	/* Release resources, unregister device */
> > > +	nand_release(mtd);  
> > 
> > What about MTD core deregistration?  
> nand_release(), it self will do that.

My bad.

> >   
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +/* Match table for device tree binding */ static const struct
> > > +of_device_id pl353_nand_of_match[] = {
> > > +	{ .compatible = "arm,pl353-nand-r2p1" },
> > > +	{},
> > > +};

Thanks,
Miquèl

RE: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm pl353 smc nand interface

[Naga Sureshkumar Relli]

Hi Miquel,

> -----Original Message-----
> From: Miquel Raynal [mailto:miquel.raynal@bootlin.com]
> Sent: Thursday, June 28, 2018 12:45 PM
> To: Naga Sureshkumar Relli <nagasure@xilinx.com>
> Cc: boris.brezillon@bootlin.com; richard@nod.at; dwmw2@infradead.org;
> computersforpeace@gmail.com; marek.vasut@gmail.com; f.fainelli@gmail.com;
> mmayer@broadcom.com; rogerq@ti.com; ladis@linux-mips.org; ada@thorsis.com;
> honghui.zhang@mediatek.com; linux-mtd@lists.infradead.org; linux-kernel@vger.kernel.org;
> nagasureshkumarrelli@gmail.com; Michal Simek <michals@xilinx.com>
> Subject: Re: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm
> pl353 smc nand interface
> 
> Hi Naga,
> 
> > > > +/**
> > > > + * pl353_nand_read_page_hwecc - Hardware ECC based page read function
> > > > + * @mtd:		Pointer to the mtd info structure
> > > > + * @chip:		Pointer to the NAND chip info structure
> > > > + * @buf:		Pointer to the buffer to store read data
> > > > + * @oob_required:	Caller requires OOB data read to chip->oob_poi
> > > > + * @page:		Page number to read
> > > > + *
> > > > + * This functions reads data and checks the data integrity by
> > > > +comparing hardware
> > > > + * generated ECC values and read ECC values from spare area.
> > > > + *
> > > > + * Return:	0 always and updates ECC operation status in to MTD structure
> > > > + */
> > > > +static int pl353_nand_read_page_hwecc(struct mtd_info *mtd,
> > > > +				      struct nand_chip *chip,
> > > > +				      u8 *buf, int oob_required, int page) {
> > > > +	int i, stat, eccsize = chip->ecc.size;
> > > > +	int eccbytes = chip->ecc.bytes;
> > > > +	int eccsteps = chip->ecc.steps;
> > > > +	u8 *p = buf;
> > > > +	u8 *ecc_calc = chip->ecc.calc_buf;
> > > > +	u8 *ecc = chip->ecc.code_buf;
> > > > +	unsigned int max_bitflips = 0;
> > > > +	u8 *oob_ptr;
> > > > +	u32 ret;
> > > > +	unsigned long data_phase_addr;
> > > > +	struct pl353_nand_info *xnfc =
> > > > +		container_of(chip, struct pl353_nand_info, chip);
> > > > +	unsigned long nand_offset = (unsigned long
> > > > +__force)xnfc->nand_base;
> > > > +
> > > > +	pl353_prepare_cmd(mtd, chip, page, 0, NAND_CMD_READ0,
> > > > +			  NAND_CMD_READSTART, 1);
> > > > +	ndelay(100);
> > >
> > > What is this delay for?
> > We have seen failures with out this delay, with older code.
> > But i will check this by removing this delay, in this new driver.
> 
> Please check all of them. We should get rid of random delays like that.
> Either there is something to poll, or there is a specific value to use (you can get them from the
> SDR interface structure).
Sure. 
> 
> [...]
> 
> > > > +
> > > > +	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
> > > > +		return -EINVAL;
> > >
> > > Why?
> > It is similar to
> > if (chipnr < 0)
> > 	return 0;
> 
> Mmmmmh, no?
> 
> (return 0) != (return -EINVAL)
> 
> The core is asking you to check if the controller driver support particular timings (usually
> ONFI modes 1-5). Returning an error means "I only support the slowest timings" which, I
> suppose, is wrong. Please fix this and compare the speeds.
Ok.
> 
> > hence written like that.
> > Also if I didn't do that, then probe is failing.
> > Am I missing some thing?
> > >
> 
> [...]
> 
> > > > +/**
> > > > + * pl353_nand_probe - Probe method for the NAND driver
> > > > + * @pdev:	Pointer to the platform_device structure
> > > > + *
> > > > + * This function initializes the driver data structures and the hardware.
> > > > + *
> > > > + * Return:	0 on success or error value on failure
> > > > + */
> > > > +static int pl353_nand_probe(struct platform_device *pdev) {
> > > > +	struct pl353_nand_info *xnfc;
> > > > +	struct mtd_info *mtd;
> > > > +	struct nand_chip *chip;
> > > > +	struct resource *res;
> > > > +	struct device_node *np;
> > > > +	u32 ret;
> > > > +
> > > > +	xnfc = devm_kzalloc(&pdev->dev, sizeof(*xnfc), GFP_KERNEL);
> > > > +	if (!xnfc)
> > > > +		return -ENOMEM;
> > > > +	xnfc->dev = &pdev->dev;
> > > > +	/* Map physical address of NAND flash */
> > > > +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > > +	xnfc->nand_base = devm_ioremap_resource(xnfc->dev, res);
> > > > +	if (IS_ERR(xnfc->nand_base))
> > > > +		return PTR_ERR(xnfc->nand_base);
> > > > +
> > > > +	chip = &xnfc->chip;
> > > > +	mtd = nand_to_mtd(chip);
> > > > +	chip->exec_op = pl353_nfc_exec_op;
> > > > +	nand_set_controller_data(chip, xnfc);
> > > > +	mtd->priv = chip;
> > > > +	mtd->owner = THIS_MODULE;
> > > > +	if (!mtd->name) {
> > > > +		/*
> > > > +		 * If the new bindings are used and the bootloader has not been
> > > > +		 * updated to pass a new mtdparts parameter on the cmdline, you
> > > > +		 * should define the following property in your NAND node, ie:
> > > > +		 *
> > > > +		 *	label = "pl353-nand";
> > > > +		 *
> > > > +		 * This way, mtd->name will be set by the core when
> > > > +		 * nand_set_flash_node() is called.
> > > > +		 */
> > > > +		mtd->name = devm_kasprintf(xnfc->dev, GFP_KERNEL,
> > > > +					   "%s", PL353_NAND_DRIVER_NAME);
> > > > +		if (!mtd->name) {
> > > > +			dev_err(xnfc->dev, "Failed to allocate mtd->name\n");
> > > > +			return -ENOMEM;
> > > > +		}
> > > > +	}
> > > > +	nand_set_flash_node(chip, xnfc->dev->of_node);
> > > > +
> > > > +	/* Set address of NAND IO lines */
> > > > +	chip->IO_ADDR_R = xnfc->nand_base;
> > > > +	chip->IO_ADDR_W = xnfc->nand_base;
> > > > +	/* Set the driver entry points for MTD */
> > > > +	chip->dev_ready = pl353_nand_device_ready;
> > > > +	chip->select_chip = pl353_nand_select_chip;
> > > > +	/* If we don't set this delay driver sets 20us by default */
> > > > +	np = of_get_next_parent(xnfc->dev->of_node);
> > > > +	xnfc->mclk = of_clk_get(np, 0);
> > > > +	if (IS_ERR(xnfc->mclk)) {
> > > > +		dev_err(xnfc->dev, "Failed to retrieve MCK clk\n");
> > > > +		return PTR_ERR(xnfc->mclk);
> > > > +	}
> > > > +	chip->chip_delay = 30;
> > > > +	/* Set the device option and flash width */
> > > > +	chip->options = NAND_BUSWIDTH_AUTO;
> > > > +	chip->bbt_options = NAND_BBT_USE_FLASH;
> > > > +	platform_set_drvdata(pdev, xnfc);
> > > > +	chip->setup_data_interface = pl353_setup_data_interface;
> > > > +	/* first scan to find the device and get the page size */
> > > > +	if (nand_scan_ident(mtd, 1, NULL)) {
> > > > +		dev_err(xnfc->dev, "nand_scan_ident for NAND failed\n");
> > > > +		return -ENXIO;
> > > > +	}
> 
> Space here
Ok.
> 
> > > > +	ret = pl353_nand_ecc_init(mtd, &chip->ecc, chip->ecc.mode);
> 
> ret should be checked
Ok.
> 
> > > > +	if (chip->options & NAND_BUSWIDTH_16)
> > > > +		pl353_smc_set_buswidth(PL353_SMC_MEM_WIDTH_16);
> 
> Space
Ok.
> 
> > > > +	/* second phase scan */
> > > > +	if (nand_scan_tail(mtd)) {
> > > > +		dev_err(xnfc->dev, "nand_scan_tail for NAND failed\n");
> > > > +		return -ENXIO;
> > > > +	}
> > > > +
> > > > +	mtd_device_register(mtd, NULL, 0);
> > >
> > > Check the returned code
> > Ok.
> 
> And if it returns an error, please call nand_cleanup().
Ok, I will update it.
> 
> > >
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +/**
> > > > + * pl353_nand_remove - Remove method for the NAND driver
> > > > + * @pdev:	Pointer to the platform_device structure
> > > > + *
> > > > + * This function is called if the driver module is being
> > > > +unloaded. It frees all
> > > > + * resources allocated to the device.
> > > > + *
> > > > + * Return:	0 on success or error value on failure
> > > > + */
> > > > +static int pl353_nand_remove(struct platform_device *pdev) {
> > > > +	struct pl353_nand_info *xnfc = platform_get_drvdata(pdev);
> > > > +	struct mtd_info *mtd = nand_to_mtd(&xnfc->chip);
> > > > +
> > > > +	/* Release resources, unregister device */
> > > > +	nand_release(mtd);
> > >
> > > What about MTD core deregistration?
> > nand_release(), it self will do that.
> 
> My bad.
> 
> > >
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +/* Match table for device tree binding */ static const struct
> > > > +of_device_id pl353_nand_of_match[] = {
> > > > +	{ .compatible = "arm,pl353-nand-r2p1" },
> > > > +	{},
> > > > +};
> 
> Thanks,
> Miquèl

Thanks,
Naga Sureshkumar Relli

Re: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm pl353 smc nand interface

[Linus Walleij]

On Thu, Jun 21, 2018 at 8:43 AM Naga Sureshkumar Relli
<naga.sureshkumar.relli@xilinx.com> wrote:

Thank you for your patch!

> Add driver for arm pl353 static memory controller nand interface with HW ECC
> support. This controller is used in Xilinx Zynq SoC for interfacing the NAND
> flash memory.
>
> Signed-off-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>

This driver has the same problem as the other patches:
use the ARM_AMBA primecell magic numbers detection, and
the PrimeCell bus.

Otherwise it looks good to me!

Yours,
Linus Walleij

RE: [[LINUX PATCH v10] 1/4] Devicetree: Add pl353 smc controller devicetree binding information

[Naga Sureshkumar Relli]

Hi Linus,

Thanks for the review.

> -----Original Message-----
> From: Linus Walleij [mailto:linus.walleij@linaro.org]
> Sent: Thursday, June 28, 2018 12:24 PM
> To: Naga Sureshkumar Relli <nagasure@xilinx.com>
> Cc: Boris Brezillon <boris.brezillon@bootlin.com>; Richard Weinberger <richard@nod.at>;
> David Woodhouse <dwmw2@infradead.org>; Brian Norris
> <computersforpeace@gmail.com>; Mark Vasut <marek.vasut@gmail.com>; Florian Fainelli
> <f.fainelli@gmail.com>; Markus Mayer <mmayer@broadcom.com>; Roger Quadros
> <rogerq@ti.com>; Ladislav Michl <ladis@linux-mips.org>; ada@thorsis.com;
> honghui.zhang@mediatek.com; Miquèl Raynal <miquel.raynal@bootlin.com>; linux-
> mtd@lists.infradead.org; linux-kernel@vger.kernel.org; nagasureshkumarrelli@gmail.com;
> Michal Simek <michals@xilinx.com>
> Subject: Re: [[LINUX PATCH v10] 1/4] Devicetree: Add pl353 smc controller devicetree
> binding information
> 
> On Thu, Jun 21, 2018 at 8:43 AM Naga Sureshkumar Relli
> <naga.sureshkumar.relli@xilinx.com> wrote:
> 
> Thanks for your patch!
> 
> > Add pl353 static memory controller devicetree binding information.
> >
> > Signed-off-by: Naga Sureshkumar Relli
> > <naga.sureshkumar.relli@xilinx.com>
> > +Device tree bindings for ARM PL353 static memory controller
> > +
> > +PL353 static memory controller supports two kinds of memory
> > +interfaces.i.e NAND and SRAM/NOR interfaces.
> > +The actual devices are instantiated from the child nodes of pl353 smc node.
> 
> See and reference the special PrimeCell DT bindings:
> Documentation/devicetree/bindings/arm/primecell.txt
> 
> > +Required properties:
> > +- compatible           : Must be "arm,pl353-smc-r2p1"
> 
> Should be:
> 
> "arm,pl353-smc-r2p1", "arm,primecell";
> 
> It will be possible for the Linux AMBA core to probe the device from just reading out the
> primecell ID registers, so the first compatible string will not even be used by many OS:es.
Thanks for pointing the primecell.txt, will append the "arm,primecell" entry in next version.
> 
> > +- reg                  : Controller registers map and length.
> > +- clock-names          : List of input clock names - "ref_clk", "aper_clk"
> > +                         (See clock bindings for details).
> 
> The AMBA primecell peripheral clock (clocking the silicon) must be named "apb_pclk".
Ok, will update in next version.
> 
> > +- clocks               : Clock phandles (see clock bindings for details).
> > +- address-cells                : Must be 1.
> > +- size-cells           : Must be 1.
> > +
> > +Child nodes:
> > + For NAND the "arm,pl353-nand-r2p1" and for NOR the "cfi-flash"
> > +drivers are supported as child nodes.
> > +
> > +for NAND partition information please refer the below file
> > +Documentation/devicetree/bindings/mtd/partition.txt
> > +
> > +Example:
> > +       smcc: memory-controller@e000e000
> > +                       compatible = "arm,pl353-smc-r2p1"
> 
> Add , "arm,primecell";
Ok. Will update in next version.
> 
> > +                       clock-names = "memclk", "aclk";
> 
> This doesn't even have the same name as in the bindings above, I think the latter should be
> named "apb_pclk".
Ok, it’s a mistake, I will correct it in next version.
> 
> Otherwise it looks good!
> 
> Yours,
> Linus Walleij

Thanks for your review.

Thanks,
Naga Sureshkumar Relli

RE: [[LINUX PATCH v10] 2/4] memory: pl353: Add driver for arm pl353 static memory controller

[Naga Sureshkumar Relli]

Hi Linux,

Thanks for the review.

> -----Original Message-----
> From: Linus Walleij [mailto:linus.walleij@linaro.org]
> Sent: Thursday, June 28, 2018 12:19 PM
> To: Naga Sureshkumar Relli <nagasure@xilinx.com>
> Cc: Boris Brezillon <boris.brezillon@bootlin.com>; Richard Weinberger <richard@nod.at>;
> David Woodhouse <dwmw2@infradead.org>; Brian Norris
> <computersforpeace@gmail.com>; Mark Vasut <marek.vasut@gmail.com>; Florian Fainelli
> <f.fainelli@gmail.com>; Markus Mayer <mmayer@broadcom.com>; Roger Quadros
> <rogerq@ti.com>; Ladislav Michl <ladis@linux-mips.org>; ada@thorsis.com;
> honghui.zhang@mediatek.com; Miquèl Raynal <miquel.raynal@bootlin.com>; linux-
> mtd@lists.infradead.org; linux-kernel@vger.kernel.org; nagasureshkumarrelli@gmail.com;
> Michal Simek <michals@xilinx.com>
> Subject: Re: [[LINUX PATCH v10] 2/4] memory: pl353: Add driver for arm pl353 static
> memory controller
> 
> On Thu, Jun 21, 2018 at 8:43 AM Naga Sureshkumar Relli
> <naga.sureshkumar.relli@xilinx.com> wrote:
> 
> > Add driver for arm pl353 static memory controller. This controller is
> > used in Xilinx Zynq SoC for interfacing the NAND and NOR/SRAM memory devices.
> >
> > Signed-off-by: Naga Sureshkumar Relli
> > <naga.sureshkumar.relli@xilinx.com>
> 
> (...)
> 
> > +config PL353_SMC
> > +       tristate "ARM PL35X Static Memory Controller(SMC) driver"
> > +       default y
> > +       depends on ARM
> > +       depends on ARCH_ZYNQ
> 
> depends on ARM_AMBA
Ok. I will add it next version.
> 
> > +#include <linux/platform_device.h>
> 
> This is a PrimeCell with the ARM primecell ID registers specified, so it should not use
> platform device.
Thanks for pointing these drivers. Let me go through these.

> 
> Use <linux/amba/bus.h>
> 
> It further needs to match on these magic values (found in
> 0xfe0 etc) and use the name "apb_pclk" for the peripheral
> (silicon) clock.
> 
> See examples such as:
> drivers/mmc/host/mmci.c
> drivers/tty/serial/amba-pl011.c
> drivers/video/fbdev/amba-clcd.c
> drivers/hwtracing/coresight/*
> etc for examples.
> 
> Also see and reference the special PrimeCell DT bindings:
> Documentation/devicetree/bindings/arm/primecell.txt
Ok. I will go through these bindings once.
> 
> Yours,
> Linus Walleij

Thank for your review.

Regards,
Naga Sureshkumar Relli.

RE: [[LINUX PATCH v10] 2/4] memory: pl353: Add driver for arm pl353 static memory controller

[Naga Sureshkumar Relli]

Sorry for the wrong name.

> -----Original Message-----
> From: Naga Sureshkumar Relli [mailto:nagasure@xilinx.com]
> Sent: Thursday, June 28, 2018 5:41 PM
> To: Linus Walleij <linus.walleij@linaro.org>
> Cc: Boris Brezillon <boris.brezillon@bootlin.com>; Richard Weinberger <richard@nod.at>;
> David Woodhouse <dwmw2@infradead.org>; Brian Norris
> <computersforpeace@gmail.com>; Mark Vasut <marek.vasut@gmail.com>; Florian Fainelli
> <f.fainelli@gmail.com>; Markus Mayer <mmayer@broadcom.com>; Roger Quadros
> <rogerq@ti.com>; Ladislav Michl <ladis@linux-mips.org>; ada@thorsis.com;
> honghui.zhang@mediatek.com; Miquèl Raynal <miquel.raynal@bootlin.com>; linux-
> mtd@lists.infradead.org; linux-kernel@vger.kernel.org; nagasureshkumarrelli@gmail.com;
> Michal Simek <michals@xilinx.com>
> Subject: RE: [[LINUX PATCH v10] 2/4] memory: pl353: Add driver for arm pl353 static
> memory controller
> 
> Hi Linux,
Linus.
> 
> Thanks for the review.
> 
> > -----Original Message-----
> > From: Linus Walleij [mailto:linus.walleij@linaro.org]
> > Sent: Thursday, June 28, 2018 12:19 PM
> > To: Naga Sureshkumar Relli <nagasure@xilinx.com>
> > Cc: Boris Brezillon <boris.brezillon@bootlin.com>; Richard Weinberger
> > <richard@nod.at>; David Woodhouse <dwmw2@infradead.org>; Brian Norris
> > <computersforpeace@gmail.com>; Mark Vasut <marek.vasut@gmail.com>;
> > Florian Fainelli <f.fainelli@gmail.com>; Markus Mayer
> > <mmayer@broadcom.com>; Roger Quadros <rogerq@ti.com>; Ladislav Michl
> > <ladis@linux-mips.org>; ada@thorsis.com; honghui.zhang@mediatek.com;
> > Miquèl Raynal <miquel.raynal@bootlin.com>; linux-
> > mtd@lists.infradead.org; linux-kernel@vger.kernel.org;
> > nagasureshkumarrelli@gmail.com; Michal Simek <michals@xilinx.com>
> > Subject: Re: [[LINUX PATCH v10] 2/4] memory: pl353: Add driver for arm
> > pl353 static memory controller
> >
> > On Thu, Jun 21, 2018 at 8:43 AM Naga Sureshkumar Relli
> > <naga.sureshkumar.relli@xilinx.com> wrote:
> >
> > > Add driver for arm pl353 static memory controller. This controller
> > > is used in Xilinx Zynq SoC for interfacing the NAND and NOR/SRAM memory devices.
> > >
> > > Signed-off-by: Naga Sureshkumar Relli
> > > <naga.sureshkumar.relli@xilinx.com>
> >
> > (...)
> >
> > > +config PL353_SMC
> > > +       tristate "ARM PL35X Static Memory Controller(SMC) driver"
> > > +       default y
> > > +       depends on ARM
> > > +       depends on ARCH_ZYNQ
> >
> > depends on ARM_AMBA
> Ok. I will add it next version.
> >
> > > +#include <linux/platform_device.h>
> >
> > This is a PrimeCell with the ARM primecell ID registers specified, so
> > it should not use platform device.
> Thanks for pointing these drivers. Let me go through these.
> 
> >
> > Use <linux/amba/bus.h>
> >
> > It further needs to match on these magic values (found in
> > 0xfe0 etc) and use the name "apb_pclk" for the peripheral
> > (silicon) clock.
> >
> > See examples such as:
> > drivers/mmc/host/mmci.c
> > drivers/tty/serial/amba-pl011.c
> > drivers/video/fbdev/amba-clcd.c
> > drivers/hwtracing/coresight/*
> > etc for examples.
> >
> > Also see and reference the special PrimeCell DT bindings:
> > Documentation/devicetree/bindings/arm/primecell.txt
> Ok. I will go through these bindings once.
> >
> > Yours,
> > Linus Walleij
> 
> Thank for your review.
> 
> Regards,
> Naga Sureshkumar Relli.

RE: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm pl353 smc nand interface

[Naga Sureshkumar Relli]

Hi Linus,

> -----Original Message-----
> From: Linus Walleij [mailto:linus.walleij@linaro.org]
> Sent: Thursday, June 28, 2018 1:14 PM
> To: Naga Sureshkumar Relli <nagasure@xilinx.com>
> Cc: Boris Brezillon <boris.brezillon@bootlin.com>; Richard Weinberger <richard@nod.at>;
> David Woodhouse <dwmw2@infradead.org>; Brian Norris
> <computersforpeace@gmail.com>; Mark Vasut <marek.vasut@gmail.com>; Florian Fainelli
> <f.fainelli@gmail.com>; Markus Mayer <mmayer@broadcom.com>; Roger Quadros
> <rogerq@ti.com>; Ladislav Michl <ladis@linux-mips.org>; ada@thorsis.com;
> honghui.zhang@mediatek.com; Miquèl Raynal <miquel.raynal@bootlin.com>; linux-
> mtd@lists.infradead.org; linux-kernel@vger.kernel.org; nagasureshkumarrelli@gmail.com;
> Michal Simek <michals@xilinx.com>
> Subject: Re: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm
> pl353 smc nand interface
> 
> On Thu, Jun 21, 2018 at 8:43 AM Naga Sureshkumar Relli
> <naga.sureshkumar.relli@xilinx.com> wrote:
> 
> Thank you for your patch!
> 
> > Add driver for arm pl353 static memory controller nand interface with
> > HW ECC support. This controller is used in Xilinx Zynq SoC for
> > interfacing the NAND flash memory.
> >
> > Signed-off-by: Naga Sureshkumar Relli
> > <naga.sureshkumar.relli@xilinx.com>
> 
> This driver has the same problem as the other patches:
> use the ARM_AMBA primecell magic numbers detection, and the PrimeCell bus.
Here the child is NAND controller and the parent is PL353 SMC, 
so do we need to update this also as AMBA driver?

Thanks,
Naga Sureshkumar Relli


> 
> Otherwise it looks good to me!
> 
> Yours,
> Linus Walleij

Re: [[LINUX PATCH v10] 2/4] memory: pl353: Add driver for arm pl353 static memory controller

[Linus Walleij]

On Thu, Jun 28, 2018 at 2:11 PM Naga Sureshkumar Relli
<nagasure@xilinx.com> wrote:

> Sorry for the wrong name.

Hehe.

> > Hi Linux,
> Linus.

Everybody does this. Even myself.

Yours,
Linus Walleij

Re: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm pl353 smc nand interface

[Linus Walleij]

On Thu, Jun 28, 2018 at 2:13 PM Naga Sureshkumar Relli
<nagasure@xilinx.com> wrote:


> > This driver has the same problem as the other patches:
> > use the ARM_AMBA primecell magic numbers detection, and the PrimeCell bus.
>
> Here the child is NAND controller and the parent is PL353 SMC,
> so do we need to update this also as AMBA driver?

No, sorry. The parent is spawning another device and you
should indeed use a platform device for that.

Forget this comment.

Yours,
Linus Walleij

RE: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm pl353 smc nand interface

[Naga Sureshkumar Relli]

Hi Linus,

> -----Original Message-----
> From: Linus Walleij [mailto:linus.walleij@linaro.org]
> Sent: Thursday, June 28, 2018 11:44 PM
> To: Naga Sureshkumar Relli <nagasure@xilinx.com>
> Cc: Boris Brezillon <boris.brezillon@bootlin.com>; Richard Weinberger <richard@nod.at>;
> David Woodhouse <dwmw2@infradead.org>; Brian Norris
> <computersforpeace@gmail.com>; Mark Vasut <marek.vasut@gmail.com>; Florian Fainelli
> <f.fainelli@gmail.com>; Markus Mayer <mmayer@broadcom.com>; Roger Quadros
> <rogerq@ti.com>; Ladislav Michl <ladis@linux-mips.org>; ada@thorsis.com;
> honghui.zhang@mediatek.com; Miquèl Raynal <miquel.raynal@bootlin.com>; linux-
> mtd@lists.infradead.org; linux-kernel@vger.kernel.org; nagasureshkumarrelli@gmail.com;
> Michal Simek <michals@xilinx.com>
> Subject: Re: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm
> pl353 smc nand interface
> 
> On Thu, Jun 28, 2018 at 2:13 PM Naga Sureshkumar Relli <nagasure@xilinx.com> wrote:
> 
> 
> > > This driver has the same problem as the other patches:
> > > use the ARM_AMBA primecell magic numbers detection, and the PrimeCell bus.
> >
> > Here the child is NAND controller and the parent is PL353 SMC, so do
> > we need to update this also as AMBA driver?
> 
> No, sorry. The parent is spawning another device and you should indeed use a platform device
> for that.
> 
Ok, you mean platform driver model is sufficient for both pl353-smc.c and pl353_nand.c drivers?
Or AMBA model is for pl353-smc and platform driver model is for pl353-nand?

Thanks,
Naga Sureshkumar Relli.

> Forget this comment.
> 
> Yours,
> Linus Walleij

Re: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm pl353 smc nand interface

[Linus Walleij]

On Fri, Jun 29, 2018 at 6:15 AM Naga Sureshkumar Relli
<nagasure@xilinx.com> wrote:
> > On Thu, Jun 28, 2018 at 2:13 PM Naga Sureshkumar Relli <nagasure@xilinx.com> wrote:
> >
> >
> > > > This driver has the same problem as the other patches:
> > > > use the ARM_AMBA primecell magic numbers detection, and the PrimeCell bus.
> > >
> > > Here the child is NAND controller and the parent is PL353 SMC, so do
> > > we need to update this also as AMBA driver?
> >
> > No, sorry. The parent is spawning another device and you should indeed use a platform device
> > for that.
> >
> Ok, you mean platform driver model is sufficient for both pl353-smc.c and pl353_nand.c drivers?
> Or AMBA model is for pl353-smc and platform driver model is for pl353-nand?

The latter, AMBA primecell bus for pl353-smc and platform device for the
nand subdevice.

Platform device is for anything that cannot be autodetected with e.g.
magic hardare numbers, and the first device can be autodetected as a
prime cell but not the subdevice.

Yours,
Linus Walleij

RE: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm pl353 smc nand interface

[Naga Sureshkumar Relli]

Hi Linus,

> -----Original Message-----
> From: Linus Walleij [mailto:linus.walleij@linaro.org]
> Sent: Monday, July 2, 2018 7:18 PM
> To: Naga Sureshkumar Relli <nagasure@xilinx.com>
> Cc: Boris Brezillon <boris.brezillon@bootlin.com>; Richard Weinberger <richard@nod.at>;
> David Woodhouse <dwmw2@infradead.org>; Brian Norris
> <computersforpeace@gmail.com>; Mark Vasut <marek.vasut@gmail.com>; Florian Fainelli
> <f.fainelli@gmail.com>; Markus Mayer <mmayer@broadcom.com>; Roger Quadros
> <rogerq@ti.com>; Ladislav Michl <ladis@linux-mips.org>; ada@thorsis.com;
> honghui.zhang@mediatek.com; Miquèl Raynal <miquel.raynal@bootlin.com>; linux-
> mtd@lists.infradead.org; linux-kernel@vger.kernel.org; nagasureshkumarrelli@gmail.com;
> Michal Simek <michals@xilinx.com>
> Subject: Re: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm
> pl353 smc nand interface
> 
> On Fri, Jun 29, 2018 at 6:15 AM Naga Sureshkumar Relli <nagasure@xilinx.com> wrote:
> > > On Thu, Jun 28, 2018 at 2:13 PM Naga Sureshkumar Relli <nagasure@xilinx.com>
> wrote:
> > >
> > >
> > > > > This driver has the same problem as the other patches:
> > > > > use the ARM_AMBA primecell magic numbers detection, and the PrimeCell bus.
> > > >
> > > > Here the child is NAND controller and the parent is PL353 SMC, so
> > > > do we need to update this also as AMBA driver?
> > >
> > > No, sorry. The parent is spawning another device and you should
> > > indeed use a platform device for that.
> > >
> > Ok, you mean platform driver model is sufficient for both pl353-smc.c and pl353_nand.c
> drivers?
> > Or AMBA model is for pl353-smc and platform driver model is for pl353-nand?
> 
> The latter, AMBA primecell bus for pl353-smc and platform device for the nand subdevice.
> 
> Platform device is for anything that cannot be autodetected with e.g.
> magic hardare numbers, and the first device can be autodetected as a prime cell but not the
> subdevice.
Thanks for your inputs, I already started updating this.
I will send v11.

Thanks,
Naga Sureshkumar Relli.
> 
> Yours,
> Linus Walleij

RE: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm pl353 smc nand interface

[Naga Sureshkumar Relli]

Hi Miquel,

> -----Original Message-----
> From: Miquel Raynal [mailto:miquel.raynal@bootlin.com]
> Sent: Thursday, June 28, 2018 12:45 PM
> To: Naga Sureshkumar Relli <nagasure@xilinx.com>
> Cc: boris.brezillon@bootlin.com; richard@nod.at; dwmw2@infradead.org;
> computersforpeace@gmail.com; marek.vasut@gmail.com; f.fainelli@gmail.com;
> mmayer@broadcom.com; rogerq@ti.com; ladis@linux-mips.org; ada@thorsis.com;
> honghui.zhang@mediatek.com; linux-mtd@lists.infradead.org; linux-kernel@vger.kernel.org;
> nagasureshkumarrelli@gmail.com; Michal Simek <michals@xilinx.com>
> Subject: Re: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm
> pl353 smc nand interface
> 
> Hi Naga,
> 
> > > > +/**
> > > > + * pl353_nand_read_page_hwecc - Hardware ECC based page read function
> > > > + * @mtd:		Pointer to the mtd info structure
> > > > + * @chip:		Pointer to the NAND chip info structure
> > > > + * @buf:		Pointer to the buffer to store read data
> > > > + * @oob_required:	Caller requires OOB data read to chip->oob_poi
> > > > + * @page:		Page number to read
> > > > + *
> > > > + * This functions reads data and checks the data integrity by
> > > > +comparing hardware
> > > > + * generated ECC values and read ECC values from spare area.
> > > > + *
> > > > + * Return:	0 always and updates ECC operation status in to MTD structure
> > > > + */
> > > > +static int pl353_nand_read_page_hwecc(struct mtd_info *mtd,
> > > > +				      struct nand_chip *chip,
> > > > +				      u8 *buf, int oob_required, int page) {
> > > > +	int i, stat, eccsize = chip->ecc.size;
> > > > +	int eccbytes = chip->ecc.bytes;
> > > > +	int eccsteps = chip->ecc.steps;
> > > > +	u8 *p = buf;
> > > > +	u8 *ecc_calc = chip->ecc.calc_buf;
> > > > +	u8 *ecc = chip->ecc.code_buf;
> > > > +	unsigned int max_bitflips = 0;
> > > > +	u8 *oob_ptr;
> > > > +	u32 ret;
> > > > +	unsigned long data_phase_addr;
> > > > +	struct pl353_nand_info *xnfc =
> > > > +		container_of(chip, struct pl353_nand_info, chip);
> > > > +	unsigned long nand_offset = (unsigned long
> > > > +__force)xnfc->nand_base;
> > > > +
> > > > +	pl353_prepare_cmd(mtd, chip, page, 0, NAND_CMD_READ0,
> > > > +			  NAND_CMD_READSTART, 1);
> > > > +	ndelay(100);
> > >
> > > What is this delay for?
> > We have seen failures with out this delay, with older code.
> > But i will check this by removing this delay, in this new driver.
> 
> Please check all of them. We should get rid of random delays like that.
> Either there is something to poll, or there is a specific value to use (you can get them from the
> SDR interface structure).
> 
> [...]
> 
> > > > +
> > > > +	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
> > > > +		return -EINVAL;
> > >
> > > Why?
> > It is similar to
> > if (chipnr < 0)
> > 	return 0;
> 
> Mmmmmh, no?
> 
> (return 0) != (return -EINVAL)
> 
> The core is asking you to check if the controller driver support particular timings (usually
> ONFI modes 1-5). Returning an error means "I only support the slowest timings" which, I
> suppose, is wrong. Please fix this and compare the speeds.
I tried updating the driver as per your comments.
But I am facing an issue here.
The part I am using is http://www.cypress.com/file/207521/download.
This part doesn't support get/set features. But the controller supports it.
In this case, the frame work is doing like this
If chip supports set_features, then it issues the ONFI_FEATURE_ADDR_TIMING_MODE other wise not.
In our case it won't and then next it simply changes the controller mode. Hence both are in different timing mode and not
Able to communicate with the nand flash device.
https://elixir.bootlin.com/linux/v4.18-rc3/source/drivers/mtd/nand/raw/nand_base.c#L1285
Am I missing something?
Could you please help on this.

The code snippet is like this
tatic int pl353_setup_data_interface(struct mtd_info *mtd, int csline,
				       const struct nand_data_interface *conf)
{
	sdr = nand_get_sdr_timings(conf);
	if (IS_ERR(sdr)) {

		return PTR_ERR(sdr);
	}
	if (csline == NAND_DATA_IFACE_CHECK_ONLY) {
		return 0;
	}
}

Thanks,
Naga Sureshkumar Relli.

Re: [[LINUX PATCH v10] 4/4] mtd: rawnand: pl353: Add basic driver for arm pl353 smc nand interface

[Miquel Raynal]

Hi Naga,

[...]

> > > > > +
> > > > > +	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
> > > > > +		return -EINVAL;  
> > > >
> > > > Why?  
> > > It is similar to
> > > if (chipnr < 0)
> > > 	return 0;  
> > 
> > Mmmmmh, no?
> > 
> > (return 0) != (return -EINVAL)
> > 
> > The core is asking you to check if the controller driver support particular timings (usually
> > ONFI modes 1-5). Returning an error means "I only support the slowest timings" which, I
> > suppose, is wrong. Please fix this and compare the speeds.  
> I tried updating the driver as per your comments.
> But I am facing an issue here.
> The part I am using is http://www.cypress.com/file/207521/download.
> This part doesn't support get/set features. But the controller supports it.
> In this case, the frame work is doing like this
> If chip supports set_features, then it issues the ONFI_FEATURE_ADDR_TIMING_MODE other wise not.

Yes because some NAND parts are broken and do not support set feature
while working naturally at an higher rate than the slowest default one.

> In our case it won't and then next it simply changes the controller mode. Hence both are in different timing mode and not

If you look at the table 3.4 of your NAND part specification, you can
see that it supports mode 0-4. Hence the core will suppose it can
switch the controller timings to mode 4. Now, is your controller able
to support these speeds? Maybe it only supports non-EDO modes (0-3)
and mode 4 cannot be achieved?

> Able to communicate with the nand flash device.
> https://elixir.bootlin.com/linux/v4.18-rc3/source/drivers/mtd/nand/raw/nand_base.c#L1285
> Am I missing something?
> Could you please help on this.
> 
> The code snippet is like this
> tatic int pl353_setup_data_interface(struct mtd_info *mtd, int csline,
> 				       const struct nand_data_interface *conf)
> {
> 	sdr = nand_get_sdr_timings(conf);
> 	if (IS_ERR(sdr)) {
> 
> 		return PTR_ERR(sdr);
> 	}
> 	if (csline == NAND_DATA_IFACE_CHECK_ONLY) {
> 		return 0;
> 	}
> }
> 
> Thanks,
> Naga Sureshkumar Relli.

Thanks,
Miquèl