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* [ v3 0/3] mtd: rawnand: add STM32 FMC2 NAND flash controller driver
@ 2018-11-29 16:41 Christophe Kerello
  2018-11-29 16:41 ` [ v3 1/3] dt-bindings: mtd: stm32_fmc2: add STM32 FMC2 NAND controller documentation Christophe Kerello
                   ` (2 more replies)
  0 siblings, 3 replies; 14+ messages in thread
From: Christophe Kerello @ 2018-11-29 16:41 UTC (permalink / raw)
  To: boris.brezillon, miquel.raynal, richard, dwmw2,
	computersforpeace, marek.vasut, robh+dt, mark.rutland
  Cc: linux-mtd, linux-kernel, devicetree, linux-stm32, Christophe Kerello

This patchset adds the support for the STMicroelectronics FMC2 NAND flash
controller found on STM32MP SOCs.

This patchset supports:
  - the command sequencer feature, a hardware accelerator for read/write
    within a page
  - the manual mode feature, useful for debug purpose
  - a maximum 8k page size
  - following ECC strength and step size
	- nand-ecc-strength = <8>, nand-ecc-step-size = <512> (BCH8)
	- nand-ecc-strength = <4>, nand-ecc-step-size = <512> (BCH4)
	- nand-ecc-strength = <1>, nand-ecc-step-size = <512> (Extended
	  ecc based on HAMMING)
    
This patchset has been tested on Micron MT29F8G08ABACAH4 (8-bit SLC NAND)
and MT29F8G16ABACAH4 (16-bit SLC NAND)

Changes v3:
 - modify clocks property description
 - add NAND reg property description
 - stm32_fmc2_nfc inherits from nand_controller structure
 - rewrite stm32_fmc2_read_data/stm32_fmc2_write_data functions
   to handle aligned and not aligned buffers
 - replace uint8_t by u8
 - use of NAND_ROW_ADDR_3 option

Changes v2:
 - separate the controller structure and the NAND chip structure
 - remove timings description from the device tree
 - fix typo issues
 - fix kbuildrobot issues

Christophe Kerello (3):
  dt-bindings: mtd: stm32_fmc2: add STM32 FMC2 NAND controller
    documentation
  mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver
  mtd: rawnand: stm32_fmc2: add manual mode

 .../devicetree/bindings/mtd/stm32-fmc2-nand.txt    |   61 +
 drivers/mtd/nand/raw/Kconfig                       |    9 +
 drivers/mtd/nand/raw/Makefile                      |    1 +
 drivers/mtd/nand/raw/stm32_fmc2_nand.c             | 2073 ++++++++++++++++++++
 4 files changed, 2144 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mtd/stm32-fmc2-nand.txt
 create mode 100644 drivers/mtd/nand/raw/stm32_fmc2_nand.c

-- 
1.9.1


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [ v3 1/3] dt-bindings: mtd: stm32_fmc2: add STM32 FMC2 NAND controller documentation
  2018-11-29 16:41 [ v3 0/3] mtd: rawnand: add STM32 FMC2 NAND flash controller driver Christophe Kerello
@ 2018-11-29 16:41 ` Christophe Kerello
  2018-12-07 23:42   ` Rob Herring
  2018-11-29 16:41 ` [ v3 2/3] mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver Christophe Kerello
  2018-11-29 16:41 ` [ v3 3/3] mtd: rawnand: stm32_fmc2: add manual mode Christophe Kerello
  2 siblings, 1 reply; 14+ messages in thread
From: Christophe Kerello @ 2018-11-29 16:41 UTC (permalink / raw)
  To: boris.brezillon, miquel.raynal, richard, dwmw2,
	computersforpeace, marek.vasut, robh+dt, mark.rutland
  Cc: linux-mtd, linux-kernel, devicetree, linux-stm32, Christophe Kerello

This patch adds the documentation of the device tree bindings for the STM32
FMC2 NAND controller.

Signed-off-by: Christophe Kerello <christophe.kerello@st.com>
---
 .../devicetree/bindings/mtd/stm32-fmc2-nand.txt    | 61 ++++++++++++++++++++++
 1 file changed, 61 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mtd/stm32-fmc2-nand.txt

diff --git a/Documentation/devicetree/bindings/mtd/stm32-fmc2-nand.txt b/Documentation/devicetree/bindings/mtd/stm32-fmc2-nand.txt
new file mode 100644
index 0000000..ad2bef8
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/stm32-fmc2-nand.txt
@@ -0,0 +1,61 @@
+STMicroelectronics Flexible Memory Controller 2 (FMC2)
+NAND Interface
+
+Required properties:
+- compatible: Should be one of:
+              * st,stm32mp15-fmc2
+- reg: NAND flash controller memory areas.
+       First region contains the register location.
+       Regions 2 to 4 respectively contain the data, command,
+       and address space for CS0.
+       Regions 5 to 7 contain the same areas for CS1.
+- interrupts: The interrupt number
+- pinctrl-0: Standard Pinctrl phandle (see: pinctrl/pinctrl-bindings.txt)
+- clocks: The clock needed by the NAND flash controller
+
+Optional properties:
+- resets: Reference to a reset controller asserting the FMC controller
+- dmas: DMA specifiers (see: dma/stm32-mdma.txt)
+- dma-names: Must be "tx", "rx" and "ecc"
+
+* NAND device bindings:
+
+Required properties:
+- reg: describes the CS lines assigned to the NAND device.
+
+Optional properties:
+- nand-on-flash-bbt: see nand.txt
+- nand-ecc-strength: see nand.txt
+- nand-ecc-step-size: see nand.txt
+
+The following ECC strength and step size are currently supported:
+ - nand-ecc-strength = <1>, nand-ecc-step-size = <512> (Hamming)
+ - nand-ecc-strength = <4>, nand-ecc-step-size = <512> (BCH4)
+ - nand-ecc-strength = <8>, nand-ecc-step-size = <512> (BCH8) (default)
+
+Example:
+
+	fmc: nand-controller@58002000 {
+		compatible = "st,stm32mp15-fmc2";
+		reg = <0x58002000 0x1000>,
+		      <0x80000000 0x1000>,
+		      <0x88010000 0x1000>,
+		      <0x88020000 0x1000>,
+		      <0x81000000 0x1000>,
+		      <0x89010000 0x1000>,
+		      <0x89020000 0x1000>;
+		interrupts = <GIC_SPI 48 IRQ_TYPE_LEVEL_HIGH>;
+		clocks = <&rcc FMC_K>;
+		resets = <&rcc FMC_R>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&fmc_pins_a>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		nand@0 {
+			reg = <0>;
+			nand-on-flash-bbt;
+			#address-cells = <1>;
+			#size-cells = <1>;
+		};
+	};
-- 
1.9.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [ v3 2/3] mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver
  2018-11-29 16:41 [ v3 0/3] mtd: rawnand: add STM32 FMC2 NAND flash controller driver Christophe Kerello
  2018-11-29 16:41 ` [ v3 1/3] dt-bindings: mtd: stm32_fmc2: add STM32 FMC2 NAND controller documentation Christophe Kerello
@ 2018-11-29 16:41 ` Christophe Kerello
  2018-12-07  9:06   ` Linus Walleij
  2018-12-07 10:18   ` Miquel Raynal
  2018-11-29 16:41 ` [ v3 3/3] mtd: rawnand: stm32_fmc2: add manual mode Christophe Kerello
  2 siblings, 2 replies; 14+ messages in thread
From: Christophe Kerello @ 2018-11-29 16:41 UTC (permalink / raw)
  To: boris.brezillon, miquel.raynal, richard, dwmw2,
	computersforpeace, marek.vasut, robh+dt, mark.rutland
  Cc: linux-mtd, linux-kernel, devicetree, linux-stm32, Christophe Kerello

The driver adds the support for the STMicroelectronics FMC2 NAND
Controller found on STM32MP SOCs.

This patch is based on FMC2 command sequencer.
The purpose of the command sequencer is to facilitate the programming
and the reading of NAND flash pages with the ECC and to free the CPU
of sequencing tasks.
It requires one DMA channel for write and two DMA channels for read
operations.

Only NAND_ECC_HW mode is actually supported.
The driver supports a maximum 8k page size.
The following ECC strength and step size are currently supported:
 - nand-ecc-strength = <8>, nand-ecc-step-size = <512> (BCH8)
 - nand-ecc-strength = <4>, nand-ecc-step-size = <512> (BCH4)
 - nand-ecc-strength = <1>, nand-ecc-step-size = <512> (Extended ECC
   based on Hamming)

This patch has been tested on Micron MT29F8G08ABACAH4 and
MT29F8G16ABACAH4

Signed-off-by: Christophe Kerello <christophe.kerello@st.com>
---
 drivers/mtd/nand/raw/Kconfig           |    9 +
 drivers/mtd/nand/raw/Makefile          |    1 +
 drivers/mtd/nand/raw/stm32_fmc2_nand.c | 1808 ++++++++++++++++++++++++++++++++
 3 files changed, 1818 insertions(+)
 create mode 100644 drivers/mtd/nand/raw/stm32_fmc2_nand.c

diff --git a/drivers/mtd/nand/raw/Kconfig b/drivers/mtd/nand/raw/Kconfig
index 1a55d3e..0f479be 100644
--- a/drivers/mtd/nand/raw/Kconfig
+++ b/drivers/mtd/nand/raw/Kconfig
@@ -541,4 +541,13 @@ config MTD_NAND_TEGRA
 	  is supported. Extra OOB bytes when using HW ECC are currently
 	  not supported.
 
+config MTD_NAND_STM32_FMC2
+	tristate "Support for NAND controller on STM32MP SoCs"
+	depends on MACH_STM32MP157 || COMPILE_TEST
+	help
+	  Enables support for NAND Flash chips on SoCs containing the FMC2
+	  NAND controller. This controller is found on STM32MP SoCs.
+	  The controller supports a maximum 8k page size and supports
+	  a maximum 8-bit correction error per sector of 512 bytes.
+
 endif # MTD_NAND
diff --git a/drivers/mtd/nand/raw/Makefile b/drivers/mtd/nand/raw/Makefile
index 57159b3..325bc9e 100644
--- a/drivers/mtd/nand/raw/Makefile
+++ b/drivers/mtd/nand/raw/Makefile
@@ -56,6 +56,7 @@ 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_TEGRA)		+= tegra_nand.o
+obj-$(CONFIG_MTD_NAND_STM32_FMC2)	+= stm32_fmc2_nand.o
 
 nand-objs := nand_base.o nand_legacy.o nand_bbt.o nand_timings.o nand_ids.o
 nand-objs += nand_onfi.o
diff --git a/drivers/mtd/nand/raw/stm32_fmc2_nand.c b/drivers/mtd/nand/raw/stm32_fmc2_nand.c
new file mode 100644
index 0000000..b62b052
--- /dev/null
+++ b/drivers/mtd/nand/raw/stm32_fmc2_nand.c
@@ -0,0 +1,1808 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics 2018
+ * Author: Christophe Kerello <christophe.kerello@st.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/mtd/rawnand.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+
+/* Bad block marker length */
+#define FMC2_BBM_LEN			2
+
+/* ECC step size */
+#define FMC2_ECC_STEP_SIZE		512
+
+/* BCHDSRx registers length */
+#define FMC2_BCHDSRS_LEN		20
+
+/* HECCR length */
+#define FMC2_HECCR_LEN			4
+
+/* Max requests done for a 8k nand page size */
+#define FMC2_MAX_SG			16
+
+/* Max chip enable */
+#define FMC2_MAX_CE			2
+
+/* Max ECC buffer length */
+#define FMC2_MAX_ECC_BUF_LEN		(FMC2_BCHDSRS_LEN * FMC2_MAX_SG)
+
+/* Timings */
+#define FMC2_THIZ			1
+#define FMC2_TIO			8000
+#define FMC2_TSYNC			3000
+#define FMC2_PCR_TIMING_MASK		0xf
+#define FMC2_PMEM_PATT_TIMING_MASK	0xff
+
+/* FMC2 Controller Registers */
+#define FMC2_BCR1			0x0
+#define FMC2_PCR			0x80
+#define FMC2_SR				0x84
+#define FMC2_PMEM			0x88
+#define FMC2_PATT			0x8c
+#define FMC2_HECCR			0x94
+#define FMC2_CSQCR			0x200
+#define FMC2_CSQCFGR1			0x204
+#define FMC2_CSQCFGR2			0x208
+#define FMC2_CSQCFGR3			0x20c
+#define FMC2_CSQAR1			0x210
+#define FMC2_CSQAR2			0x214
+#define FMC2_CSQIER			0x220
+#define FMC2_CSQISR			0x224
+#define FMC2_CSQICR			0x228
+#define FMC2_CSQEMSR			0x230
+#define FMC2_BCHIER			0x250
+#define FMC2_BCHISR			0x254
+#define FMC2_BCHICR			0x258
+#define FMC2_BCHPBR1			0x260
+#define FMC2_BCHPBR2			0x264
+#define FMC2_BCHPBR3			0x268
+#define FMC2_BCHPBR4			0x26c
+#define FMC2_BCHDSR0			0x27c
+#define FMC2_BCHDSR1			0x280
+#define FMC2_BCHDSR2			0x284
+#define FMC2_BCHDSR3			0x288
+#define FMC2_BCHDSR4			0x28c
+
+/* Register: FMC2_BCR1 */
+#define FMC2_BCR1_FMC2EN		BIT(31)
+
+/* Register: FMC2_PCR */
+#define FMC2_PCR_PWAITEN		BIT(1)
+#define FMC2_PCR_PBKEN			BIT(2)
+#define FMC2_PCR_PWID_MASK		GENMASK(5, 4)
+#define FMC2_PCR_PWID(x)		(((x) & 0x3) << 4)
+#define FMC2_PCR_PWID_BUSWIDTH_8	0
+#define FMC2_PCR_PWID_BUSWIDTH_16	1
+#define FMC2_PCR_ECCEN			BIT(6)
+#define FMC2_PCR_ECCALG			BIT(8)
+#define FMC2_PCR_TCLR_MASK		GENMASK(12, 9)
+#define FMC2_PCR_TCLR(x)		(((x) & 0xf) << 9)
+#define FMC2_PCR_TCLR_DEFAULT		0xf
+#define FMC2_PCR_TAR_MASK		GENMASK(16, 13)
+#define FMC2_PCR_TAR(x)			(((x) & 0xf) << 13)
+#define FMC2_PCR_TAR_DEFAULT		0xf
+#define FMC2_PCR_ECCSS_MASK		GENMASK(19, 17)
+#define FMC2_PCR_ECCSS(x)		(((x) & 0x7) << 17)
+#define FMC2_PCR_ECCSS_512		1
+#define FMC2_PCR_ECCSS_2048		3
+#define FMC2_PCR_BCHECC			BIT(24)
+#define FMC2_PCR_WEN			BIT(25)
+
+/* Register: FMC2_SR */
+#define FMC2_SR_NWRF			BIT(6)
+
+/* Register: FMC2_PMEM */
+#define FMC2_PMEM_MEMSET(x)		(((x) & 0xff) << 0)
+#define FMC2_PMEM_MEMWAIT(x)		(((x) & 0xff) << 8)
+#define FMC2_PMEM_MEMHOLD(x)		(((x) & 0xff) << 16)
+#define FMC2_PMEM_MEMHIZ(x)		(((x) & 0xff) << 24)
+#define FMC2_PMEM_DEFAULT		0x0a0a0a0a
+
+/* Register: FMC2_PATT */
+#define FMC2_PATT_ATTSET(x)		(((x) & 0xff) << 0)
+#define FMC2_PATT_ATTWAIT(x)		(((x) & 0xff) << 8)
+#define FMC2_PATT_ATTHOLD(x)		(((x) & 0xff) << 16)
+#define FMC2_PATT_ATTHIZ(x)		(((x) & 0xff) << 24)
+#define FMC2_PATT_DEFAULT		0x0a0a0a0a
+
+/* Register: FMC2_CSQCR */
+#define FMC2_CSQCR_CSQSTART		BIT(0)
+
+/* Register: FMC2_CSQCFGR1 */
+#define FMC2_CSQCFGR1_CMD2EN		BIT(1)
+#define FMC2_CSQCFGR1_DMADEN		BIT(2)
+#define FMC2_CSQCFGR1_ACYNBR(x)		(((x) & 0x7) << 4)
+#define FMC2_CSQCFGR1_CMD1(x)		(((x) & 0xff) << 8)
+#define FMC2_CSQCFGR1_CMD2(x)		(((x) & 0xff) << 16)
+#define FMC2_CSQCFGR1_CMD1T		BIT(24)
+#define FMC2_CSQCFGR1_CMD2T		BIT(25)
+
+/* Register: FMC2_CSQCFGR2 */
+#define FMC2_CSQCFGR2_SQSDTEN		BIT(0)
+#define FMC2_CSQCFGR2_RCMD2EN		BIT(1)
+#define FMC2_CSQCFGR2_DMASEN		BIT(2)
+#define FMC2_CSQCFGR2_RCMD1(x)		(((x) & 0xff) << 8)
+#define FMC2_CSQCFGR2_RCMD2(x)		(((x) & 0xff) << 16)
+#define FMC2_CSQCFGR2_RCMD1T		BIT(24)
+#define FMC2_CSQCFGR2_RCMD2T		BIT(25)
+
+/* Register: FMC2_CSQCFGR3 */
+#define FMC2_CSQCFGR3_SNBR(x)		(((x) & 0x1f) << 8)
+#define FMC2_CSQCFGR3_AC1T		BIT(16)
+#define FMC2_CSQCFGR3_AC2T		BIT(17)
+#define FMC2_CSQCFGR3_AC3T		BIT(18)
+#define FMC2_CSQCFGR3_AC4T		BIT(19)
+#define FMC2_CSQCFGR3_AC5T		BIT(20)
+#define FMC2_CSQCFGR3_SDT		BIT(21)
+#define FMC2_CSQCFGR3_RAC1T		BIT(22)
+#define FMC2_CSQCFGR3_RAC2T		BIT(23)
+
+/* Register: FMC2_CSQCAR1 */
+#define FMC2_CSQCAR1_ADDC1(x)		(((x) & 0xff) << 0)
+#define FMC2_CSQCAR1_ADDC2(x)		(((x) & 0xff) << 8)
+#define FMC2_CSQCAR1_ADDC3(x)		(((x) & 0xff) << 16)
+#define FMC2_CSQCAR1_ADDC4(x)		(((x) & 0xff) << 24)
+
+/* Register: FMC2_CSQCAR2 */
+#define FMC2_CSQCAR2_ADDC5(x)		(((x) & 0xff) << 0)
+#define FMC2_CSQCAR2_NANDCEN(x)		(((x) & 0x3) << 10)
+#define FMC2_CSQCAR2_SAO(x)		(((x) & 0xffff) << 16)
+
+/* Register: FMC2_CSQIER */
+#define FMC2_CSQIER_TCIE		BIT(0)
+
+/* Register: FMC2_CSQICR */
+#define FMC2_CSQICR_CLEAR_IRQ		GENMASK(4, 0)
+
+/* Register: FMC2_CSQEMSR */
+#define FMC2_CSQEMSR_SEM		GENMASK(15, 0)
+
+/* Register: FMC2_BCHIER */
+#define FMC2_BCHIER_DERIE		BIT(1)
+#define FMC2_BCHIER_EPBRIE		BIT(4)
+
+/* Register: FMC2_BCHICR */
+#define FMC2_BCHICR_CLEAR_IRQ		GENMASK(4, 0)
+
+/* Register: FMC2_BCHDSR0 */
+#define FMC2_BCHDSR0_DUE		BIT(0)
+#define FMC2_BCHDSR0_DEF		BIT(1)
+#define FMC2_BCHDSR0_DEN_MASK		GENMASK(7, 4)
+#define FMC2_BCHDSR0_DEN_SHIFT		4
+
+/* Register: FMC2_BCHDSR1 */
+#define FMC2_BCHDSR1_EBP1_MASK		GENMASK(12, 0)
+#define FMC2_BCHDSR1_EBP2_MASK		GENMASK(28, 16)
+#define FMC2_BCHDSR1_EBP2_SHIFT		16
+
+/* Register: FMC2_BCHDSR2 */
+#define FMC2_BCHDSR2_EBP3_MASK		GENMASK(12, 0)
+#define FMC2_BCHDSR2_EBP4_MASK		GENMASK(28, 16)
+#define FMC2_BCHDSR2_EBP4_SHIFT		16
+
+/* Register: FMC2_BCHDSR3 */
+#define FMC2_BCHDSR3_EBP5_MASK		GENMASK(12, 0)
+#define FMC2_BCHDSR3_EBP6_MASK		GENMASK(28, 16)
+#define FMC2_BCHDSR3_EBP6_SHIFT		16
+
+/* Register: FMC2_BCHDSR4 */
+#define FMC2_BCHDSR4_EBP7_MASK		GENMASK(12, 0)
+#define FMC2_BCHDSR4_EBP8_MASK		GENMASK(28, 16)
+#define FMC2_BCHDSR4_EBP8_SHIFT		16
+
+enum stm32_fmc2_ecc {
+	FMC2_ECC_HAM = 1,
+	FMC2_ECC_BCH4 = 4,
+	FMC2_ECC_BCH8 = 8
+};
+
+struct stm32_fmc2_timings {
+	u8 tclr;
+	u8 tar;
+	u8 thiz;
+	u8 twait;
+	u8 thold_mem;
+	u8 tset_mem;
+	u8 thold_att;
+	u8 tset_att;
+};
+
+struct stm32_fmc2_nand {
+	struct nand_chip chip;
+	struct stm32_fmc2_timings timings;
+	int ncs;
+	int cs_used[FMC2_MAX_CE];
+};
+
+static inline struct stm32_fmc2_nand *to_fmc2_nand(struct nand_chip *chip)
+{
+	return container_of(chip, struct stm32_fmc2_nand, chip);
+}
+
+struct stm32_fmc2_nfc {
+	struct nand_controller base;
+	struct stm32_fmc2_nand nand;
+	struct device *dev;
+	void __iomem *io_base;
+	void __iomem *data_base[FMC2_MAX_CE];
+	void __iomem *cmd_base[FMC2_MAX_CE];
+	void __iomem *addr_base[FMC2_MAX_CE];
+	phys_addr_t io_phys_addr;
+	phys_addr_t data_phys_addr[FMC2_MAX_CE];
+	struct clk *clk;
+
+	struct dma_chan *dma_tx_ch;
+	struct dma_chan *dma_rx_ch;
+	struct dma_chan *dma_ecc_ch;
+	struct sg_table dma_data_sg;
+	struct sg_table dma_ecc_sg;
+	u8 *ecc_buf;
+	int dma_ecc_len;
+
+	struct completion complete;
+	struct completion dma_data_complete;
+	struct completion dma_ecc_complete;
+
+	u8 cs_assigned;
+	int cs_sel;
+};
+
+static inline struct stm32_fmc2_nfc *to_stm32_nfc(struct nand_controller *base)
+{
+	return container_of(base, struct stm32_fmc2_nfc, base);
+}
+
+/* Timings configuration */
+static void stm32_fmc2_timings_init(struct nand_chip *chip)
+{
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+	struct stm32_fmc2_nand *nand = to_fmc2_nand(chip);
+	struct stm32_fmc2_timings *timings = &nand->timings;
+	u32 pcr = readl_relaxed(fmc2->io_base + FMC2_PCR);
+	u32 pmem, patt;
+
+	/* Set tclr/tar timings */
+	pcr &= ~FMC2_PCR_TCLR_MASK;
+	pcr |= FMC2_PCR_TCLR(timings->tclr);
+	pcr &= ~FMC2_PCR_TAR_MASK;
+	pcr |= FMC2_PCR_TAR(timings->tar);
+
+	/* Set tset/twait/thold/thiz timings in common bank */
+	pmem = FMC2_PMEM_MEMSET(timings->tset_mem);
+	pmem |= FMC2_PMEM_MEMWAIT(timings->twait);
+	pmem |= FMC2_PMEM_MEMHOLD(timings->thold_mem);
+	pmem |= FMC2_PMEM_MEMHIZ(timings->thiz);
+
+	/* Set tset/twait/thold/thiz timings in attribut bank */
+	patt = FMC2_PATT_ATTSET(timings->tset_att);
+	patt |= FMC2_PATT_ATTWAIT(timings->twait);
+	patt |= FMC2_PATT_ATTHOLD(timings->thold_att);
+	patt |= FMC2_PATT_ATTHIZ(timings->thiz);
+
+	writel_relaxed(pcr, fmc2->io_base + FMC2_PCR);
+	writel_relaxed(pmem, fmc2->io_base + FMC2_PMEM);
+	writel_relaxed(patt, fmc2->io_base + FMC2_PATT);
+}
+
+/* Controller configuration */
+static void stm32_fmc2_setup(struct nand_chip *chip)
+{
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+	u32 pcr = readl_relaxed(fmc2->io_base + FMC2_PCR);
+
+	/* Configure ECC algorithm (default configuration is Hamming) */
+	pcr &= ~FMC2_PCR_ECCALG;
+	pcr &= ~FMC2_PCR_BCHECC;
+	if (chip->ecc.strength == FMC2_ECC_BCH8) {
+		pcr |= FMC2_PCR_ECCALG;
+		pcr |= FMC2_PCR_BCHECC;
+	} else if (chip->ecc.strength == FMC2_ECC_BCH4) {
+		pcr |= FMC2_PCR_ECCALG;
+	}
+
+	/* Set buswidth */
+	pcr &= ~FMC2_PCR_PWID_MASK;
+	if (chip->options & NAND_BUSWIDTH_16)
+		pcr |= FMC2_PCR_PWID(FMC2_PCR_PWID_BUSWIDTH_16);
+
+	/* Set ECC sector size */
+	pcr &= ~FMC2_PCR_ECCSS_MASK;
+	pcr |= FMC2_PCR_ECCSS(FMC2_PCR_ECCSS_512);
+
+	writel_relaxed(pcr, fmc2->io_base + FMC2_PCR);
+}
+
+/* Select target */
+static int stm32_fmc2_select_chip(struct nand_chip *chip, int chipnr)
+{
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+	struct stm32_fmc2_nand *nand = to_fmc2_nand(chip);
+	struct dma_slave_config dma_cfg;
+	int ret;
+
+	if (nand->cs_used[chipnr] == fmc2->cs_sel)
+		return 0;
+
+	fmc2->cs_sel = nand->cs_used[chipnr];
+
+	/* FMC2 setup routine */
+	stm32_fmc2_setup(chip);
+
+	/* Apply timings */
+	stm32_fmc2_timings_init(chip);
+
+	if (fmc2->dma_tx_ch && fmc2->dma_rx_ch) {
+		memset(&dma_cfg, 0, sizeof(dma_cfg));
+		dma_cfg.src_addr = fmc2->data_phys_addr[fmc2->cs_sel];
+		dma_cfg.dst_addr = fmc2->data_phys_addr[fmc2->cs_sel];
+		dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+		dma_cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+		dma_cfg.src_maxburst = 32;
+		dma_cfg.dst_maxburst = 32;
+
+		ret = dmaengine_slave_config(fmc2->dma_tx_ch, &dma_cfg);
+		if (ret) {
+			dev_err(fmc2->dev, "tx DMA engine slave config failed\n");
+			return ret;
+		}
+
+		ret = dmaengine_slave_config(fmc2->dma_rx_ch, &dma_cfg);
+		if (ret) {
+			dev_err(fmc2->dev, "rx DMA engine slave config failed\n");
+			return ret;
+		}
+	}
+
+	if (fmc2->dma_ecc_ch) {
+		/*
+		 * Hamming: we read HECCR register
+		 * BCH4/BCH8: we read BCHDSRSx registers
+		 */
+		memset(&dma_cfg, 0, sizeof(dma_cfg));
+		dma_cfg.src_addr = fmc2->io_phys_addr;
+		dma_cfg.src_addr += chip->ecc.strength == FMC2_ECC_HAM ?
+				    FMC2_HECCR : FMC2_BCHDSR0;
+		dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+
+		ret = dmaengine_slave_config(fmc2->dma_ecc_ch, &dma_cfg);
+		if (ret) {
+			dev_err(fmc2->dev, "ECC DMA engine slave config failed\n");
+			return ret;
+		}
+
+		/* Calculate ECC length needed for one sector */
+		fmc2->dma_ecc_len = chip->ecc.strength == FMC2_ECC_HAM ?
+				    FMC2_HECCR_LEN : FMC2_BCHDSRS_LEN;
+	}
+
+	return 0;
+}
+
+/* Set bus width to 16-bit or 8-bit */
+static void stm32_fmc2_set_buswidth_16(struct stm32_fmc2_nfc *fmc2, bool set)
+{
+	u32 pcr = readl_relaxed(fmc2->io_base + FMC2_PCR);
+
+	pcr &= ~FMC2_PCR_PWID_MASK;
+	if (set)
+		pcr |= FMC2_PCR_PWID(FMC2_PCR_PWID_BUSWIDTH_16);
+	writel_relaxed(pcr, fmc2->io_base + FMC2_PCR);
+}
+
+/* Enable irq sources in case of the sequencer is used */
+static inline void stm32_fmc2_enable_seq_irq(struct stm32_fmc2_nfc *fmc2)
+{
+	u32 csqier = readl_relaxed(fmc2->io_base + FMC2_CSQIER);
+
+	csqier |= FMC2_CSQIER_TCIE;
+
+	writel_relaxed(csqier, fmc2->io_base + FMC2_CSQIER);
+}
+
+/* Disable irq sources in case of the sequencer is used */
+static inline void stm32_fmc2_disable_seq_irq(struct stm32_fmc2_nfc *fmc2)
+{
+	u32 csqier = readl_relaxed(fmc2->io_base + FMC2_CSQIER);
+
+	csqier &= ~FMC2_CSQIER_TCIE;
+
+	writel_relaxed(csqier, fmc2->io_base + FMC2_CSQIER);
+}
+
+/* Clear irq sources in case of the sequencer is used */
+static inline void stm32_fmc2_clear_seq_irq(struct stm32_fmc2_nfc *fmc2)
+{
+	writel_relaxed(FMC2_CSQICR_CLEAR_IRQ, fmc2->io_base + FMC2_CSQICR);
+}
+
+/*
+ * ECC Hamming calculation
+ * ECC is 3 bytes for 512 bytes of data (supports error correction up to
+ * max of 1-bit)
+ */
+static inline void stm32_fmc2_ham_set_ecc(const u32 ecc_sta, u8 *ecc)
+{
+	ecc[0] = ecc_sta;
+	ecc[1] = ecc_sta >> 8;
+	ecc[2] = ecc_sta >> 16;
+}
+
+static int stm32_fmc2_ham_correct(struct nand_chip *chip, u8 *dat,
+				  u8 *read_ecc, u8 *calc_ecc)
+{
+	u8 bit_position = 0, b0, b1, b2;
+	u32 byte_addr = 0, b;
+	u32 i, shifting = 1;
+
+	/* Indicate which bit and byte is faulty (if any) */
+	b0 = read_ecc[0] ^ calc_ecc[0];
+	b1 = read_ecc[1] ^ calc_ecc[1];
+	b2 = read_ecc[2] ^ calc_ecc[2];
+	b = b0 | (b1 << 8) | (b2 << 16);
+
+	/* No errors */
+	if (likely(!b))
+		return 0;
+
+	/* Calculate bit position */
+	for (i = 0; i < 3; i++) {
+		switch (b % 4) {
+		case 2:
+			bit_position += shifting;
+		case 1:
+			break;
+		default:
+			return -EBADMSG;
+		}
+		shifting <<= 1;
+		b >>= 2;
+	}
+
+	/* Calculate byte position */
+	shifting = 1;
+	for (i = 0; i < 9; i++) {
+		switch (b % 4) {
+		case 2:
+			byte_addr += shifting;
+		case 1:
+			break;
+		default:
+			return -EBADMSG;
+		}
+		shifting <<= 1;
+		b >>= 2;
+	}
+
+	/* Flip the bit */
+	dat[byte_addr] ^= (1 << bit_position);
+
+	return 1;
+}
+
+/* BCH algorithm correction */
+static int stm32_fmc2_bch_decode(int eccsize, u8 *dat, u32 *ecc_sta)
+{
+	u32 bchdsr0 = ecc_sta[0];
+	u32 bchdsr1 = ecc_sta[1];
+	u32 bchdsr2 = ecc_sta[2];
+	u32 bchdsr3 = ecc_sta[3];
+	u32 bchdsr4 = ecc_sta[4];
+	u16 pos[8];
+	int i, den;
+	unsigned int nb_errs = 0;
+
+	/* No errors found */
+	if (likely(!(bchdsr0 & FMC2_BCHDSR0_DEF)))
+		return 0;
+
+	/* Too many errors detected */
+	if (unlikely(bchdsr0 & FMC2_BCHDSR0_DUE))
+		return -EBADMSG;
+
+	pos[0] = bchdsr1 & FMC2_BCHDSR1_EBP1_MASK;
+	pos[1] = (bchdsr1 & FMC2_BCHDSR1_EBP2_MASK) >> FMC2_BCHDSR1_EBP2_SHIFT;
+	pos[2] = bchdsr2 & FMC2_BCHDSR2_EBP3_MASK;
+	pos[3] = (bchdsr2 & FMC2_BCHDSR2_EBP4_MASK) >> FMC2_BCHDSR2_EBP4_SHIFT;
+	pos[4] = bchdsr3 & FMC2_BCHDSR3_EBP5_MASK;
+	pos[5] = (bchdsr3 & FMC2_BCHDSR3_EBP6_MASK) >> FMC2_BCHDSR3_EBP6_SHIFT;
+	pos[6] = bchdsr4 & FMC2_BCHDSR4_EBP7_MASK;
+	pos[7] = (bchdsr4 & FMC2_BCHDSR4_EBP8_MASK) >> FMC2_BCHDSR4_EBP8_SHIFT;
+
+	den = (bchdsr0 & FMC2_BCHDSR0_DEN_MASK) >> FMC2_BCHDSR0_DEN_SHIFT;
+	for (i = 0; i < den; i++) {
+		if (pos[i] < eccsize * 8) {
+			change_bit(pos[i], (unsigned long *)dat);
+			nb_errs++;
+		}
+	}
+
+	return nb_errs;
+}
+
+/* Sequencer read/write configuration */
+static void stm32_fmc2_rw_page_init(struct nand_chip *chip, int page,
+				    int raw, bool write_data)
+{
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+	struct mtd_info *mtd = nand_to_mtd(chip);
+	u32 csqcfgr1, csqcfgr2, csqcfgr3;
+	u32 csqar1, csqar2;
+	u32 ecc_offset = mtd->writesize + FMC2_BBM_LEN;
+	u32 pcr = readl_relaxed(fmc2->io_base + FMC2_PCR);
+
+	if (write_data)
+		pcr |= FMC2_PCR_WEN;
+	else
+		pcr &= ~FMC2_PCR_WEN;
+	writel_relaxed(pcr, fmc2->io_base + FMC2_PCR);
+
+	/*
+	 * - Set Program Page/Page Read command
+	 * - Enable DMA request data
+	 * - Set timings
+	 */
+	csqcfgr1 = FMC2_CSQCFGR1_DMADEN | FMC2_CSQCFGR1_CMD1T;
+	if (write_data)
+		csqcfgr1 |= FMC2_CSQCFGR1_CMD1(NAND_CMD_SEQIN);
+	else
+		csqcfgr1 |= FMC2_CSQCFGR1_CMD1(NAND_CMD_READ0) |
+			    FMC2_CSQCFGR1_CMD2EN |
+			    FMC2_CSQCFGR1_CMD2(NAND_CMD_READSTART) |
+			    FMC2_CSQCFGR1_CMD2T;
+
+	/*
+	 * - Set Random Data Input/Random Data Read command
+	 * - Enable the sequencer to access the Spare data area
+	 * - Enable  DMA request status decoding for read
+	 * - Set timings
+	 */
+	if (write_data)
+		csqcfgr2 = FMC2_CSQCFGR2_RCMD1(NAND_CMD_RNDIN);
+	else
+		csqcfgr2 = FMC2_CSQCFGR2_RCMD1(NAND_CMD_RNDOUT) |
+			   FMC2_CSQCFGR2_RCMD2EN |
+			   FMC2_CSQCFGR2_RCMD2(NAND_CMD_RNDOUTSTART) |
+			   FMC2_CSQCFGR2_RCMD1T |
+			   FMC2_CSQCFGR2_RCMD2T;
+	if (!raw) {
+		csqcfgr2 |= write_data ? 0 : FMC2_CSQCFGR2_DMASEN;
+		csqcfgr2 |= FMC2_CSQCFGR2_SQSDTEN;
+	}
+
+	/*
+	 * - Set the number of sectors to be written
+	 * - Set timings
+	 */
+	csqcfgr3 = FMC2_CSQCFGR3_SNBR(chip->ecc.steps - 1);
+	if (write_data) {
+		csqcfgr3 |= FMC2_CSQCFGR3_RAC2T;
+		if (chip->options & NAND_ROW_ADDR_3)
+			csqcfgr3 |= FMC2_CSQCFGR3_AC5T;
+		else
+			csqcfgr3 |= FMC2_CSQCFGR3_AC4T;
+	}
+
+	/*
+	 * Set the fourth first address cycles
+	 * Byte 1 and byte 2 => column, we start at 0x0
+	 * Byte 3 and byte 4 => page
+	 */
+	csqar1 = FMC2_CSQCAR1_ADDC3(page);
+	csqar1 |= FMC2_CSQCAR1_ADDC4(page >> 8);
+
+	/*
+	 * - Set chip enable number
+	 * - Set ECC byte offset in the spare area
+	 * - Calculate the number of address cycles to be issued
+	 * - Set byte 5 of address cycle if needed
+	 */
+	csqar2 = FMC2_CSQCAR2_NANDCEN(fmc2->cs_sel);
+	if (chip->options & NAND_BUSWIDTH_16)
+		csqar2 |= FMC2_CSQCAR2_SAO(ecc_offset >> 1);
+	else
+		csqar2 |= FMC2_CSQCAR2_SAO(ecc_offset);
+	if (chip->options & NAND_ROW_ADDR_3) {
+		csqcfgr1 |= FMC2_CSQCFGR1_ACYNBR(5);
+		csqar2 |= FMC2_CSQCAR2_ADDC5(page >> 16);
+	} else {
+		csqcfgr1 |= FMC2_CSQCFGR1_ACYNBR(4);
+	}
+
+	writel_relaxed(csqcfgr1, fmc2->io_base + FMC2_CSQCFGR1);
+	writel_relaxed(csqcfgr2, fmc2->io_base + FMC2_CSQCFGR2);
+	writel_relaxed(csqcfgr3, fmc2->io_base + FMC2_CSQCFGR3);
+	writel_relaxed(csqar1, fmc2->io_base + FMC2_CSQAR1);
+	writel_relaxed(csqar2, fmc2->io_base + FMC2_CSQAR2);
+}
+
+static void stm32_fmc2_dma_callback(void *arg)
+{
+	complete((struct completion *)arg);
+}
+
+/* Read/write data from/to a page */
+static int stm32_fmc2_xfer(struct nand_chip *chip, const u8 *buf,
+			   int raw, bool write_data)
+{
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+	struct dma_async_tx_descriptor *desc_data, *desc_ecc;
+	struct scatterlist *sg;
+	struct dma_chan *dma_ch = fmc2->dma_rx_ch;
+	enum dma_data_direction dma_data_dir = DMA_FROM_DEVICE;
+	enum dma_transfer_direction dma_transfer_dir = DMA_DEV_TO_MEM;
+	u32 csqcr = readl_relaxed(fmc2->io_base + FMC2_CSQCR);
+	int eccsteps = chip->ecc.steps;
+	int eccsize = chip->ecc.size;
+	const u8 *p = buf;
+	int s, ret;
+
+	/* Configure DMA data */
+	if (write_data) {
+		dma_data_dir = DMA_TO_DEVICE;
+		dma_transfer_dir = DMA_MEM_TO_DEV;
+		dma_ch = fmc2->dma_tx_ch;
+	}
+
+	for_each_sg(fmc2->dma_data_sg.sgl, sg, eccsteps, s) {
+		sg_set_buf(sg, p, eccsize);
+		p += eccsize;
+	}
+
+	ret = dma_map_sg(fmc2->dev, fmc2->dma_data_sg.sgl,
+			 eccsteps, dma_data_dir);
+	if (ret < 0)
+		return ret;
+
+	desc_data = dmaengine_prep_slave_sg(dma_ch, fmc2->dma_data_sg.sgl,
+					    eccsteps, dma_transfer_dir,
+					    DMA_PREP_INTERRUPT);
+	if (!desc_data) {
+		ret = -ENOMEM;
+		goto err_unmap_data;
+	}
+
+	reinit_completion(&fmc2->dma_data_complete);
+	reinit_completion(&fmc2->complete);
+	desc_data->callback = stm32_fmc2_dma_callback;
+	desc_data->callback_param = &fmc2->dma_data_complete;
+	ret = dma_submit_error(dmaengine_submit(desc_data));
+	if (ret)
+		goto err_unmap_data;
+
+	dma_async_issue_pending(dma_ch);
+
+	if (!write_data && !raw) {
+		/* Configure DMA ECC status */
+		p = fmc2->ecc_buf;
+		for_each_sg(fmc2->dma_ecc_sg.sgl, sg, eccsteps, s) {
+			sg_set_buf(sg, p, fmc2->dma_ecc_len);
+			p += fmc2->dma_ecc_len;
+		}
+
+		ret = dma_map_sg(fmc2->dev, fmc2->dma_ecc_sg.sgl,
+				 eccsteps, dma_data_dir);
+		if (ret < 0)
+			goto err_unmap_data;
+
+		desc_ecc = dmaengine_prep_slave_sg(fmc2->dma_ecc_ch,
+						   fmc2->dma_ecc_sg.sgl,
+						   eccsteps, dma_transfer_dir,
+						   DMA_PREP_INTERRUPT);
+		if (!desc_ecc) {
+			ret = -ENOMEM;
+			goto err_unmap_ecc;
+		}
+
+		reinit_completion(&fmc2->dma_ecc_complete);
+		desc_ecc->callback = stm32_fmc2_dma_callback;
+		desc_ecc->callback_param = &fmc2->dma_ecc_complete;
+		ret = dma_submit_error(dmaengine_submit(desc_ecc));
+		if (ret)
+			goto err_unmap_ecc;
+
+		dma_async_issue_pending(fmc2->dma_ecc_ch);
+	}
+
+	stm32_fmc2_clear_seq_irq(fmc2);
+	stm32_fmc2_enable_seq_irq(fmc2);
+
+	/* Start the transfer */
+	csqcr |= FMC2_CSQCR_CSQSTART;
+	writel_relaxed(csqcr, fmc2->io_base + FMC2_CSQCR);
+
+	/* Wait end of sequencer transfer */
+	if (!wait_for_completion_timeout(&fmc2->complete,
+					 msecs_to_jiffies(1000))) {
+		dev_err(fmc2->dev, "seq timeout\n");
+		stm32_fmc2_disable_seq_irq(fmc2);
+		dmaengine_terminate_all(dma_ch);
+		if (!write_data && !raw)
+			dmaengine_terminate_all(fmc2->dma_ecc_ch);
+		ret = -ETIMEDOUT;
+		goto err_unmap_ecc;
+	}
+
+	/* Wait DMA data transfer completion */
+	if (!wait_for_completion_timeout(&fmc2->dma_data_complete,
+					 msecs_to_jiffies(100))) {
+		dev_err(fmc2->dev, "data DMA timeout\n");
+		dmaengine_terminate_all(dma_ch);
+		ret = -ETIMEDOUT;
+	}
+
+	/* Wait DMA ECC transfer completion */
+	if (!write_data && !raw) {
+		if (!wait_for_completion_timeout(&fmc2->dma_ecc_complete,
+						 msecs_to_jiffies(100))) {
+			dev_err(fmc2->dev, "ECC DMA timeout\n");
+			dmaengine_terminate_all(fmc2->dma_ecc_ch);
+			ret = -ETIMEDOUT;
+		}
+	}
+
+err_unmap_ecc:
+	if (!write_data && !raw)
+		dma_unmap_sg(fmc2->dev, fmc2->dma_ecc_sg.sgl,
+			     eccsteps, dma_data_dir);
+
+err_unmap_data:
+	dma_unmap_sg(fmc2->dev, fmc2->dma_data_sg.sgl, eccsteps, dma_data_dir);
+
+	return ret;
+}
+
+static int stm32_fmc2_sequencer_write(struct nand_chip *chip,
+				      const u8 *buf, int oob_required,
+				      int page, int raw)
+{
+	struct mtd_info *mtd = nand_to_mtd(chip);
+	int ret;
+
+	/* Configure the sequencer */
+	stm32_fmc2_rw_page_init(chip, page, raw, true);
+
+	/* Write the page */
+	ret = stm32_fmc2_xfer(chip, buf, raw, true);
+	if (ret)
+		return ret;
+
+	/* Write oob */
+	if (oob_required) {
+		ret = nand_change_write_column_op(chip, mtd->writesize,
+						  chip->oob_poi, mtd->oobsize,
+						  false);
+		if (ret)
+			return ret;
+	}
+
+	return nand_prog_page_end_op(chip);
+}
+
+static int stm32_fmc2_sequencer_write_page(struct nand_chip *chip,
+					   const u8 *buf,
+					   int oob_required,
+					   int page)
+{
+	int ret;
+
+	/* Select the target */
+	ret = stm32_fmc2_select_chip(chip, chip->cur_cs);
+	if (ret)
+		return ret;
+
+	return stm32_fmc2_sequencer_write(chip, buf, oob_required, page, false);
+}
+
+static int stm32_fmc2_sequencer_write_page_raw(struct nand_chip *chip,
+					       const u8 *buf,
+					       int oob_required,
+					       int page)
+{
+	int ret;
+
+	/* Select the target */
+	ret = stm32_fmc2_select_chip(chip, chip->cur_cs);
+	if (ret)
+		return ret;
+
+	return stm32_fmc2_sequencer_write(chip, buf, oob_required, page, true);
+}
+
+/* Get a status indicating which sectors have errors */
+static inline u16 stm32_fmc2_get_mapping_status(struct stm32_fmc2_nfc *fmc2)
+{
+	u32 csqemsr = readl_relaxed(fmc2->io_base + FMC2_CSQEMSR);
+
+	return csqemsr & FMC2_CSQEMSR_SEM;
+}
+
+static int stm32_fmc2_sequencer_correct(struct nand_chip *chip, u8 *dat,
+					u8 *read_ecc, u8 *calc_ecc)
+{
+	struct mtd_info *mtd = nand_to_mtd(chip);
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+	int eccbytes = chip->ecc.bytes;
+	int eccsteps = chip->ecc.steps;
+	int eccstrength = chip->ecc.strength;
+	int i, s, eccsize = chip->ecc.size;
+	u32 *ecc_sta = (u32 *)fmc2->ecc_buf;
+	u16 sta_map = stm32_fmc2_get_mapping_status(fmc2);
+	unsigned int max_bitflips = 0;
+
+	for (i = 0, s = 0; s < eccsteps; s++, i += eccbytes, dat += eccsize) {
+		int stat = 0;
+
+		if (eccstrength == FMC2_ECC_HAM) {
+			/* Ecc_sta = FMC2_HECCR */
+			if (sta_map & BIT(s)) {
+				stm32_fmc2_ham_set_ecc(*ecc_sta, &calc_ecc[i]);
+				stat = stm32_fmc2_ham_correct(chip, dat,
+							      &read_ecc[i],
+							      &calc_ecc[i]);
+			}
+			ecc_sta++;
+		} else {
+			/*
+			 * Ecc_sta[0] = FMC2_BCHDSR0
+			 * Ecc_sta[1] = FMC2_BCHDSR1
+			 * Ecc_sta[2] = FMC2_BCHDSR2
+			 * Ecc_sta[3] = FMC2_BCHDSR3
+			 * Ecc_sta[4] = FMC2_BCHDSR4
+			 */
+			if (sta_map & BIT(s))
+				stat = stm32_fmc2_bch_decode(eccsize, dat,
+							     ecc_sta);
+			ecc_sta += 5;
+		}
+
+		if (stat == -EBADMSG)
+			/* Check for empty pages with bitflips */
+			stat = nand_check_erased_ecc_chunk(dat, eccsize,
+							   &read_ecc[i],
+							   eccbytes,
+							   NULL, 0,
+							   eccstrength);
+
+		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;
+}
+
+static int stm32_fmc2_sequencer_read_page(struct nand_chip *chip, u8 *buf,
+					  int oob_required, int page)
+{
+	struct mtd_info *mtd = nand_to_mtd(chip);
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+	u8 *ecc_calc = chip->ecc.calc_buf;
+	u8 *ecc_code = chip->ecc.code_buf;
+	u16 sta_map;
+	int ret;
+
+	/* Select the target */
+	ret = stm32_fmc2_select_chip(chip, chip->cur_cs);
+	if (ret)
+		return ret;
+
+	/* Configure the sequencer */
+	stm32_fmc2_rw_page_init(chip, page, 0, false);
+
+	/* Read the page */
+	ret = stm32_fmc2_xfer(chip, buf, 0, false);
+	if (ret)
+		return ret;
+
+	sta_map = stm32_fmc2_get_mapping_status(fmc2);
+
+	/* Check if errors happen */
+	if (likely(!sta_map)) {
+		if (oob_required)
+			return nand_change_read_column_op(chip, mtd->writesize,
+							  chip->oob_poi,
+							  mtd->oobsize, false);
+
+		return 0;
+	}
+
+	/* Read oob */
+	ret = nand_change_read_column_op(chip, mtd->writesize,
+					 chip->oob_poi, mtd->oobsize, false);
+	if (ret)
+		return ret;
+
+	ret = mtd_ooblayout_get_eccbytes(mtd, ecc_code, chip->oob_poi, 0,
+					 chip->ecc.total);
+	if (ret)
+		return ret;
+
+	/* Correct data */
+	return chip->ecc.correct(chip, buf, ecc_code, ecc_calc);
+}
+
+static int stm32_fmc2_sequencer_read_page_raw(struct nand_chip *chip, u8 *buf,
+					      int oob_required, int page)
+{
+	struct mtd_info *mtd = nand_to_mtd(chip);
+	int ret;
+
+	/* Select the target */
+	ret = stm32_fmc2_select_chip(chip, chip->cur_cs);
+	if (ret)
+		return ret;
+
+	/* Configure the sequencer */
+	stm32_fmc2_rw_page_init(chip, page, 1, false);
+
+	/* Read the page */
+	ret = stm32_fmc2_xfer(chip, buf, 1, false);
+	if (ret)
+		return ret;
+
+	/* Read oob */
+	if (oob_required)
+		return nand_change_read_column_op(chip, mtd->writesize,
+						  chip->oob_poi, mtd->oobsize,
+						  false);
+
+	return 0;
+}
+
+static irqreturn_t stm32_fmc2_irq(int irq, void *dev_id)
+{
+	struct stm32_fmc2_nfc *fmc2 = (struct stm32_fmc2_nfc *)dev_id;
+
+	stm32_fmc2_disable_seq_irq(fmc2);
+
+	complete(&fmc2->complete);
+
+	return IRQ_HANDLED;
+}
+
+void stm32_fmc2_read_data(struct nand_chip *chip, void *buf,
+			  unsigned int len, bool force_8bit)
+{
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+	void __iomem *io_addr_r = fmc2->data_base[fmc2->cs_sel];
+
+	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
+		/* Reconfigure bus width to 8-bit */
+		stm32_fmc2_set_buswidth_16(fmc2, false);
+
+	if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32))) {
+		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u16)) && len) {
+			*(u8 *)buf = readb_relaxed(io_addr_r);
+			buf += sizeof(u8);
+			len -= sizeof(u8);
+		}
+
+		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
+		    len >= sizeof(u16)) {
+			*(u16 *)buf = readw_relaxed(io_addr_r);
+			buf += sizeof(u16);
+			len -= sizeof(u16);
+		}
+	}
+
+	/* Buf is aligned */
+	while (len >= sizeof(u32)) {
+		*(u32 *)buf = readl_relaxed(io_addr_r);
+		buf += sizeof(u32);
+		len -= sizeof(u32);
+	}
+
+	/* Read remaining bytes */
+	if (len >= sizeof(u16)) {
+		*(u16 *)buf = readw_relaxed(io_addr_r);
+		buf += sizeof(u16);
+		len -= sizeof(u16);
+	}
+
+	if (len)
+		*(u8 *)buf = readb_relaxed(io_addr_r);
+
+	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
+		/* Reconfigure bus width to 16-bit */
+		stm32_fmc2_set_buswidth_16(fmc2, true);
+}
+
+void stm32_fmc2_write_data(struct nand_chip *chip, const void *buf,
+			   unsigned int len, bool force_8bit)
+{
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+	void __iomem *io_addr_w = fmc2->data_base[fmc2->cs_sel];
+
+	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
+		/* Reconfigure bus width to 8-bit */
+		stm32_fmc2_set_buswidth_16(fmc2, false);
+
+	if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32))) {
+		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u16)) && len) {
+			writeb_relaxed(*(u8 *)buf, io_addr_w);
+			buf += sizeof(u8);
+			len -= sizeof(u8);
+		}
+
+		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
+		    len >= sizeof(u16)) {
+			writew_relaxed(*(u16 *)buf, io_addr_w);
+			buf += sizeof(u16);
+			len -= sizeof(u16);
+		}
+	}
+
+	/* Buf is aligned */
+	while (len >= sizeof(u32)) {
+		writel_relaxed(*(u32 *)buf, io_addr_w);
+		buf += sizeof(u32);
+		len -= sizeof(u32);
+	}
+
+	/* Write remaining bytes */
+	if (len >= sizeof(u16)) {
+		writew_relaxed(*(u16 *)buf, io_addr_w);
+		buf += sizeof(u16);
+		len -= sizeof(u16);
+	}
+
+	if (len)
+		writeb_relaxed(*(u8 *)buf, io_addr_w);
+
+	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
+		/* Reconfigure bus width to 16-bit */
+		stm32_fmc2_set_buswidth_16(fmc2, true);
+}
+
+static int stm32_fmc2_exec_op(struct nand_chip *chip,
+			      const struct nand_operation *op,
+			      bool check_only)
+{
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+	const struct nand_op_instr *instr = NULL;
+	unsigned int op_id, i;
+	int ret;
+
+	ret = stm32_fmc2_select_chip(chip, op->cs);
+	if (ret)
+		return ret;
+
+	if (check_only)
+		return ret;
+
+	for (op_id = 0; op_id < op->ninstrs; op_id++) {
+		instr = &op->instrs[op_id];
+
+		switch (instr->type) {
+		case NAND_OP_CMD_INSTR:
+			writeb_relaxed(instr->ctx.cmd.opcode,
+				       fmc2->cmd_base[fmc2->cs_sel]);
+			break;
+
+		case NAND_OP_ADDR_INSTR:
+			for (i = 0; i < instr->ctx.addr.naddrs; i++)
+				writeb_relaxed(instr->ctx.addr.addrs[i],
+					       fmc2->addr_base[fmc2->cs_sel]);
+			break;
+
+		case NAND_OP_DATA_IN_INSTR:
+			stm32_fmc2_read_data(chip, instr->ctx.data.buf.in,
+					     instr->ctx.data.len,
+					     instr->ctx.data.force_8bit);
+			break;
+
+		case NAND_OP_DATA_OUT_INSTR:
+			stm32_fmc2_write_data(chip, instr->ctx.data.buf.out,
+					      instr->ctx.data.len,
+					      instr->ctx.data.force_8bit);
+			break;
+
+		case NAND_OP_WAITRDY_INSTR:
+			ret = nand_soft_waitrdy(chip,
+						instr->ctx.waitrdy.timeout_ms);
+			break;
+		}
+	}
+
+	return ret;
+}
+
+/* Controller initialization */
+static void stm32_fmc2_init(struct stm32_fmc2_nfc *fmc2)
+{
+	u32 pcr = readl_relaxed(fmc2->io_base + FMC2_PCR);
+	u32 bcr1 = readl_relaxed(fmc2->io_base + FMC2_BCR1);
+
+	/* Set CS used to undefined */
+	fmc2->cs_sel = -1;
+
+	/* Enable wait feature and nand flash memory bank */
+	pcr |= FMC2_PCR_PWAITEN;
+	pcr |= FMC2_PCR_PBKEN;
+
+	/* Set buswidth to 8 bits mode for identification */
+	pcr &= ~FMC2_PCR_PWID_MASK;
+
+	/* ECC logic is disabled */
+	pcr &= ~FMC2_PCR_ECCEN;
+
+	/* Default mode */
+	pcr &= ~FMC2_PCR_ECCALG;
+	pcr &= ~FMC2_PCR_BCHECC;
+	pcr &= ~FMC2_PCR_WEN;
+
+	/* Set default ECC sector size */
+	pcr &= ~FMC2_PCR_ECCSS_MASK;
+	pcr |= FMC2_PCR_ECCSS(FMC2_PCR_ECCSS_2048);
+
+	/* Set default tclr/tar timings */
+	pcr &= ~FMC2_PCR_TCLR_MASK;
+	pcr |= FMC2_PCR_TCLR(FMC2_PCR_TCLR_DEFAULT);
+	pcr &= ~FMC2_PCR_TAR_MASK;
+	pcr |= FMC2_PCR_TAR(FMC2_PCR_TAR_DEFAULT);
+
+	/* Enable FMC2 controller */
+	bcr1 |= FMC2_BCR1_FMC2EN;
+
+	writel_relaxed(bcr1, fmc2->io_base + FMC2_BCR1);
+	writel_relaxed(pcr, fmc2->io_base + FMC2_PCR);
+	writel_relaxed(FMC2_PMEM_DEFAULT, fmc2->io_base + FMC2_PMEM);
+	writel_relaxed(FMC2_PATT_DEFAULT, fmc2->io_base + FMC2_PATT);
+}
+
+/* Controller timings */
+static void stm32_fmc2_calc_timings(struct nand_chip *chip,
+				    const struct nand_sdr_timings *sdrt)
+{
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+	struct stm32_fmc2_nand *nand = to_fmc2_nand(chip);
+	struct stm32_fmc2_timings *tims = &nand->timings;
+	unsigned long hclk = clk_get_rate(fmc2->clk);
+	unsigned long hclkp = NSEC_PER_SEC / (hclk / 1000);
+	int tar, tclr, thiz, twait, tset_mem, tset_att, thold_mem, thold_att;
+
+	tar = hclkp;
+	if (tar < sdrt->tAR_min)
+		tar = sdrt->tAR_min;
+	tims->tar = DIV_ROUND_UP(tar, hclkp) - 1;
+	if (tims->tar > FMC2_PCR_TIMING_MASK)
+		tims->tar = FMC2_PCR_TIMING_MASK;
+
+	tclr = hclkp;
+	if (tclr < sdrt->tCLR_min)
+		tclr = sdrt->tCLR_min;
+	tims->tclr = DIV_ROUND_UP(tclr, hclkp) - 1;
+	if (tims->tclr > FMC2_PCR_TIMING_MASK)
+		tims->tclr = FMC2_PCR_TIMING_MASK;
+
+	tims->thiz = FMC2_THIZ;
+	thiz = (tims->thiz + 1) * hclkp;
+
+	/*
+	 * tWAIT > tRP
+	 * tWAIT > tWP
+	 * tWAIT > tREA + tIO
+	 */
+	twait = hclkp;
+	if (twait < sdrt->tRP_min)
+		twait = sdrt->tRP_min;
+	if (twait < sdrt->tWP_min)
+		twait = sdrt->tWP_min;
+	if (twait < sdrt->tREA_max + FMC2_TIO)
+		twait = sdrt->tREA_max + FMC2_TIO;
+	tims->twait = DIV_ROUND_UP(twait, hclkp);
+	if (tims->twait == 0)
+		tims->twait = 1;
+	else if (tims->twait > FMC2_PMEM_PATT_TIMING_MASK)
+		tims->twait = FMC2_PMEM_PATT_TIMING_MASK;
+
+	/*
+	 * tSETUP_MEM > tCS - tWAIT
+	 * tSETUP_MEM > tALS - tWAIT
+	 * tSETUP_MEM > tDS - (tWAIT - tHIZ)
+	 */
+	tset_mem = hclkp;
+	if (sdrt->tCS_min > twait && (tset_mem < sdrt->tCS_min - twait))
+		tset_mem = sdrt->tCS_min - twait;
+	if (sdrt->tALS_min > twait && (tset_mem < sdrt->tALS_min - twait))
+		tset_mem = sdrt->tALS_min - twait;
+	if (twait > thiz && (sdrt->tDS_min > twait - thiz) &&
+	    (tset_mem < sdrt->tDS_min - (twait - thiz)))
+		tset_mem = sdrt->tDS_min - (twait - thiz);
+	tims->tset_mem = DIV_ROUND_UP(tset_mem, hclkp);
+	if (tims->tset_mem == 0)
+		tims->tset_mem = 1;
+	else if (tims->tset_mem > FMC2_PMEM_PATT_TIMING_MASK)
+		tims->tset_mem = FMC2_PMEM_PATT_TIMING_MASK;
+
+	/*
+	 * tHOLD_MEM > tCH
+	 * tHOLD_MEM > tREH - tSETUP_MEM
+	 * tHOLD_MEM > max(tRC, tWC) - (tSETUP_MEM + tWAIT)
+	 */
+	thold_mem = hclkp;
+	if (thold_mem < sdrt->tCH_min)
+		thold_mem = sdrt->tCH_min;
+	if (sdrt->tREH_min > tset_mem &&
+	    (thold_mem < sdrt->tREH_min - tset_mem))
+		thold_mem = sdrt->tREH_min - tset_mem;
+	if ((sdrt->tRC_min > tset_mem + twait) &&
+	    (thold_mem < sdrt->tRC_min - (tset_mem + twait)))
+		thold_mem = sdrt->tRC_min - (tset_mem + twait);
+	if ((sdrt->tWC_min > tset_mem + twait) &&
+	    (thold_mem < sdrt->tWC_min - (tset_mem + twait)))
+		thold_mem = sdrt->tWC_min - (tset_mem + twait);
+	tims->thold_mem = DIV_ROUND_UP(thold_mem, hclkp);
+	if (tims->thold_mem == 0)
+		tims->thold_mem = 1;
+	else if (tims->thold_mem > FMC2_PMEM_PATT_TIMING_MASK)
+		tims->thold_mem = FMC2_PMEM_PATT_TIMING_MASK;
+
+	/*
+	 * tSETUP_ATT > tCS - tWAIT
+	 * tSETUP_ATT > tCLS - tWAIT
+	 * tSETUP_ATT > tALS - tWAIT
+	 * tSETUP_ATT > tRHW - tHOLD_MEM
+	 * tSETUP_ATT > tDS - (tWAIT - tHIZ)
+	 */
+	tset_att = hclkp;
+	if (sdrt->tCS_min > twait && (tset_att < sdrt->tCS_min - twait))
+		tset_att = sdrt->tCS_min - twait;
+	if (sdrt->tCLS_min > twait && (tset_att < sdrt->tCLS_min - twait))
+		tset_att = sdrt->tCLS_min - twait;
+	if (sdrt->tALS_min > twait && (tset_att < sdrt->tALS_min - twait))
+		tset_att = sdrt->tALS_min - twait;
+	if (sdrt->tRHW_min > thold_mem &&
+	    (tset_att < sdrt->tRHW_min - thold_mem))
+		tset_att = sdrt->tRHW_min - thold_mem;
+	if (twait > thiz && (sdrt->tDS_min > twait - thiz) &&
+	    (tset_att < sdrt->tDS_min - (twait - thiz)))
+		tset_att = sdrt->tDS_min - (twait - thiz);
+	tims->tset_att = DIV_ROUND_UP(tset_att, hclkp);
+	if (tims->tset_att == 0)
+		tims->tset_att = 1;
+	else if (tims->tset_att > FMC2_PMEM_PATT_TIMING_MASK)
+		tims->tset_att = FMC2_PMEM_PATT_TIMING_MASK;
+
+	/*
+	 * tHOLD_ATT > tALH
+	 * tHOLD_ATT > tCH
+	 * tHOLD_ATT > tCLH
+	 * tHOLD_ATT > tCOH
+	 * tHOLD_ATT > tDH
+	 * tHOLD_ATT > tWB + tIO + tSYNC - tSETUP_MEM
+	 * tHOLD_ATT > tADL - tSETUP_MEM
+	 * tHOLD_ATT > tWH - tSETUP_MEM
+	 * tHOLD_ATT > tWHR - tSETUP_MEM
+	 * tHOLD_ATT > tRC - (tSETUP_ATT + tWAIT)
+	 * tHOLD_ATT > tWC - (tSETUP_ATT + tWAIT)
+	 */
+	thold_att = hclkp;
+	if (thold_att < sdrt->tALH_min)
+		thold_att = sdrt->tALH_min;
+	if (thold_att < sdrt->tCH_min)
+		thold_att = sdrt->tCH_min;
+	if (thold_att < sdrt->tCLH_min)
+		thold_att = sdrt->tCLH_min;
+	if (thold_att < sdrt->tCOH_min)
+		thold_att = sdrt->tCOH_min;
+	if (thold_att < sdrt->tDH_min)
+		thold_att = sdrt->tDH_min;
+	if ((sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC > tset_mem) &&
+	    (thold_att < sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC - tset_mem))
+		thold_att = sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC - tset_mem;
+	if (sdrt->tADL_min > tset_mem &&
+	    (thold_att < sdrt->tADL_min - tset_mem))
+		thold_att = sdrt->tADL_min - tset_mem;
+	if (sdrt->tWH_min > tset_mem &&
+	    (thold_att < sdrt->tWH_min - tset_mem))
+		thold_att = sdrt->tWH_min - tset_mem;
+	if (sdrt->tWHR_min > tset_mem &&
+	    (thold_att < sdrt->tWHR_min - tset_mem))
+		thold_att = sdrt->tWHR_min - tset_mem;
+	if ((sdrt->tRC_min > tset_att + twait) &&
+	    (thold_att < sdrt->tRC_min - (tset_att + twait)))
+		thold_att = sdrt->tRC_min - (tset_att + twait);
+	if ((sdrt->tWC_min > tset_att + twait) &&
+	    (thold_att < sdrt->tWC_min - (tset_att + twait)))
+		thold_att = sdrt->tWC_min - (tset_att + twait);
+	tims->thold_att = DIV_ROUND_UP(thold_att, hclkp);
+	if (tims->thold_att == 0)
+		tims->thold_att = 1;
+	else if (tims->thold_att > FMC2_PMEM_PATT_TIMING_MASK)
+		tims->thold_att = FMC2_PMEM_PATT_TIMING_MASK;
+}
+
+static int stm32_fmc2_setup_interface(struct nand_chip *chip, int chipnr,
+				      const struct nand_data_interface *conf)
+{
+	const struct nand_sdr_timings *sdrt;
+
+	sdrt = nand_get_sdr_timings(conf);
+	if (IS_ERR(sdrt))
+		return PTR_ERR(sdrt);
+
+	if (chipnr == NAND_DATA_IFACE_CHECK_ONLY)
+		return 0;
+
+	stm32_fmc2_calc_timings(chip, sdrt);
+
+	/* Apply timings */
+	stm32_fmc2_timings_init(chip);
+
+	return 0;
+}
+
+/* DMA configuration */
+static int stm32_fmc2_dma_setup(struct stm32_fmc2_nfc *fmc2)
+{
+	int ret;
+
+	fmc2->dma_tx_ch = dma_request_slave_channel(fmc2->dev, "tx");
+	fmc2->dma_rx_ch = dma_request_slave_channel(fmc2->dev, "rx");
+	fmc2->dma_ecc_ch = dma_request_slave_channel(fmc2->dev, "ecc");
+
+	if (fmc2->dma_ecc_ch) {
+		ret = sg_alloc_table(&fmc2->dma_ecc_sg, FMC2_MAX_SG,
+				     GFP_KERNEL);
+		if (ret)
+			return ret;
+
+		/* Allocate a buffer to store ECC status registers */
+		fmc2->ecc_buf = devm_kzalloc(fmc2->dev,
+					     FMC2_MAX_ECC_BUF_LEN,
+					     GFP_KERNEL);
+		if (!fmc2->ecc_buf)
+			return -ENOMEM;
+	} else {
+		dev_err(fmc2->dev, "ECC DMA not defined in the device tree\n");
+		return -ENOENT;
+	}
+
+	if (fmc2->dma_tx_ch && fmc2->dma_rx_ch) {
+		ret = sg_alloc_table(&fmc2->dma_data_sg, FMC2_MAX_SG,
+				     GFP_KERNEL);
+		if (ret)
+			return ret;
+
+		init_completion(&fmc2->dma_data_complete);
+		init_completion(&fmc2->dma_ecc_complete);
+	} else {
+		dev_err(fmc2->dev, "rx/tx DMA not defined in the device tree\n");
+		return -ENOENT;
+	}
+
+	return 0;
+}
+
+/* NAND callbacks setup */
+static void stm32_fmc2_nand_callbacks_setup(struct nand_chip *chip)
+{
+	/* Specific callbacks to read/write a page */
+	chip->ecc.correct = stm32_fmc2_sequencer_correct;
+	chip->ecc.write_page = stm32_fmc2_sequencer_write_page;
+	chip->ecc.read_page = stm32_fmc2_sequencer_read_page;
+	chip->ecc.write_page_raw = stm32_fmc2_sequencer_write_page_raw;
+	chip->ecc.read_page_raw = stm32_fmc2_sequencer_read_page_raw;
+
+	/* Specific configurations depending on the algo used */
+	if (chip->ecc.strength == FMC2_ECC_HAM)
+		chip->ecc.bytes = chip->options & NAND_BUSWIDTH_16 ? 4 : 3;
+	else if (chip->ecc.strength == FMC2_ECC_BCH8)
+		chip->ecc.bytes = chip->options & NAND_BUSWIDTH_16 ? 14 : 13;
+	else
+		chip->ecc.bytes = chip->options & NAND_BUSWIDTH_16 ? 8 : 7;
+}
+
+/* FMC2 layout */
+static int stm32_fmc2_nand_ooblayout_ecc(struct mtd_info *mtd, int section,
+					 struct mtd_oob_region *oobregion)
+{
+	struct nand_chip *chip = mtd_to_nand(mtd);
+	struct nand_ecc_ctrl *ecc = &chip->ecc;
+
+	if (section)
+		return -ERANGE;
+
+	oobregion->length = ecc->total;
+	oobregion->offset = FMC2_BBM_LEN;
+
+	return 0;
+}
+
+static int stm32_fmc2_nand_ooblayout_free(struct mtd_info *mtd, int section,
+					  struct mtd_oob_region *oobregion)
+{
+	struct nand_chip *chip = mtd_to_nand(mtd);
+	struct nand_ecc_ctrl *ecc = &chip->ecc;
+
+	if (section)
+		return -ERANGE;
+
+	oobregion->length = mtd->oobsize - ecc->total - FMC2_BBM_LEN;
+	oobregion->offset = ecc->total + FMC2_BBM_LEN;
+
+	return 0;
+}
+
+const struct mtd_ooblayout_ops stm32_fmc2_nand_ooblayout_ops = {
+	.ecc = stm32_fmc2_nand_ooblayout_ecc,
+	.free = stm32_fmc2_nand_ooblayout_free,
+};
+
+/* FMC2 caps */
+static int stm32_fmc2_calc_ecc_bytes(int step_size, int strength)
+{
+	/* Hamming */
+	if (strength == FMC2_ECC_HAM)
+		return 4;
+
+	/* BCH8 */
+	if (strength == FMC2_ECC_BCH8)
+		return 14;
+
+	/* BCH4 */
+	return 8;
+}
+
+NAND_ECC_CAPS_SINGLE(stm32_fmc2_ecc_caps, stm32_fmc2_calc_ecc_bytes,
+		     FMC2_ECC_STEP_SIZE,
+		     FMC2_ECC_HAM, FMC2_ECC_BCH4, FMC2_ECC_BCH8);
+
+/* FMC2 controller ops */
+static int stm32_fmc2_attach_chip(struct nand_chip *chip)
+{
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+	struct mtd_info *mtd = nand_to_mtd(chip);
+	int ret;
+
+	/*
+	 * Only NAND_ECC_HW mode is actually supported
+	 * Hamming => ecc.strength = 1
+	 * BCH4 => ecc.strength = 4
+	 * BCH8 => ecc.strength = 8
+	 * ECC sector size = 512
+	 */
+	if (chip->ecc.mode != NAND_ECC_HW) {
+		dev_err(fmc2->dev, "nand_ecc_mode is not well defined in the DT\n");
+		return -EINVAL;
+	}
+
+	ret = nand_ecc_choose_conf(chip, &stm32_fmc2_ecc_caps,
+				   mtd->oobsize - FMC2_BBM_LEN);
+	if (ret) {
+		dev_err(fmc2->dev, "no valid ECC settings set\n");
+		return ret;
+	}
+
+	if (mtd->writesize / chip->ecc.size > FMC2_MAX_SG) {
+		dev_err(fmc2->dev, "nand page size is not supported\n");
+		return -EINVAL;
+	}
+
+	if (chip->bbt_options & NAND_BBT_USE_FLASH)
+		chip->bbt_options |= NAND_BBT_NO_OOB;
+
+	/* NAND callbacks setup */
+	stm32_fmc2_nand_callbacks_setup(chip);
+
+	/* Define ECC layout */
+	mtd_set_ooblayout(mtd, &stm32_fmc2_nand_ooblayout_ops);
+
+	/* Configure bus width to 16-bit */
+	if (chip->options & NAND_BUSWIDTH_16)
+		stm32_fmc2_set_buswidth_16(fmc2, true);
+
+	return 0;
+}
+
+static const struct nand_controller_ops stm32_fmc2_nand_controller_ops = {
+	.attach_chip = stm32_fmc2_attach_chip,
+	.exec_op = stm32_fmc2_exec_op,
+	.setup_data_interface = stm32_fmc2_setup_interface,
+};
+
+/* FMC2 probe */
+static int stm32_fmc2_parse_child(struct stm32_fmc2_nfc *fmc2,
+				  struct device_node *dn)
+{
+	struct stm32_fmc2_nand *nand = &fmc2->nand;
+	u32 cs;
+	int ret, i;
+
+	if (!of_get_property(dn, "reg", &nand->ncs))
+		return -EINVAL;
+
+	nand->ncs /= sizeof(u32);
+	if (!nand->ncs) {
+		dev_err(fmc2->dev, "invalid reg property size\n");
+		return -EINVAL;
+	}
+
+	for (i = 0; i < nand->ncs; i++) {
+		ret = of_property_read_u32_index(dn, "reg", i, &cs);
+		if (ret) {
+			dev_err(fmc2->dev, "could not retrieve reg property: %d\n",
+				ret);
+			return ret;
+		}
+
+		if (cs > FMC2_MAX_CE) {
+			dev_err(fmc2->dev, "invalid reg value: %d\n", cs);
+			return -EINVAL;
+		}
+
+		if (fmc2->cs_assigned & BIT(cs)) {
+			dev_err(fmc2->dev, "cs already assigned: %d\n", cs);
+			return -EINVAL;
+		}
+
+		fmc2->cs_assigned |= BIT(cs);
+		nand->cs_used[i] = cs;
+	}
+
+	nand_set_flash_node(&nand->chip, dn);
+
+	return 0;
+}
+
+static int stm32_fmc2_parse_dt(struct stm32_fmc2_nfc *fmc2)
+{
+	struct device_node *dn = fmc2->dev->of_node;
+	struct device_node *child;
+	int nchips = of_get_child_count(dn);
+	int ret = 0;
+
+	if (!nchips) {
+		dev_err(fmc2->dev, "NAND chip not defined\n");
+		return -EINVAL;
+	}
+
+	if (nchips > 1) {
+		dev_err(fmc2->dev, "too many NAND chips defined\n");
+		return -EINVAL;
+	}
+
+	for_each_child_of_node(dn, child) {
+		ret = stm32_fmc2_parse_child(fmc2, child);
+		if (ret < 0) {
+			of_node_put(child);
+			return ret;
+		}
+	}
+
+	return ret;
+}
+
+static int stm32_fmc2_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct reset_control *rstc;
+	struct stm32_fmc2_nfc *fmc2;
+	struct stm32_fmc2_nand *nand;
+	struct resource *res;
+	struct mtd_info *mtd;
+	struct nand_chip *chip;
+	int chip_cs, mem_region, ret, irq;
+
+	fmc2 = devm_kzalloc(dev, sizeof(*fmc2), GFP_KERNEL);
+	if (!fmc2)
+		return -ENOMEM;
+
+	fmc2->dev = dev;
+	nand_controller_init(&fmc2->base);
+	fmc2->base.ops = &stm32_fmc2_nand_controller_ops;
+
+	ret = stm32_fmc2_parse_dt(fmc2);
+	if (ret)
+		return ret;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	fmc2->io_base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(fmc2->io_base))
+		return PTR_ERR(fmc2->io_base);
+
+	fmc2->io_phys_addr = res->start;
+
+	for (chip_cs = 0, mem_region = 1; chip_cs < FMC2_MAX_CE;
+	     chip_cs++, mem_region += 3) {
+		if (!(fmc2->cs_assigned & BIT(chip_cs)))
+			continue;
+
+		res = platform_get_resource(pdev, IORESOURCE_MEM, mem_region);
+		fmc2->data_base[chip_cs] = devm_ioremap_resource(dev, res);
+		if (IS_ERR(fmc2->data_base[chip_cs]))
+			return PTR_ERR(fmc2->data_base[chip_cs]);
+
+		fmc2->data_phys_addr[chip_cs] = res->start;
+
+		res = platform_get_resource(pdev, IORESOURCE_MEM,
+					    mem_region + 1);
+		fmc2->cmd_base[chip_cs] = devm_ioremap_resource(dev, res);
+		if (IS_ERR(fmc2->cmd_base[chip_cs]))
+			return PTR_ERR(fmc2->cmd_base[chip_cs]);
+
+		res = platform_get_resource(pdev, IORESOURCE_MEM,
+					    mem_region + 2);
+		fmc2->addr_base[chip_cs] = devm_ioremap_resource(dev, res);
+		if (IS_ERR(fmc2->addr_base[chip_cs]))
+			return PTR_ERR(fmc2->addr_base[chip_cs]);
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	ret = devm_request_irq(dev, irq, stm32_fmc2_irq, 0,
+			       dev_name(dev), fmc2);
+	if (ret) {
+		dev_err(dev, "failed to request irq\n");
+		return ret;
+	}
+
+	init_completion(&fmc2->complete);
+
+	fmc2->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(fmc2->clk))
+		return PTR_ERR(fmc2->clk);
+
+	ret = clk_prepare_enable(fmc2->clk);
+	if (ret) {
+		dev_err(dev, "can not enable the clock\n");
+		return ret;
+	}
+
+	rstc = devm_reset_control_get(dev, NULL);
+	if (!IS_ERR(rstc)) {
+		reset_control_assert(rstc);
+		reset_control_deassert(rstc);
+	}
+
+	/* DMA setup */
+	ret = stm32_fmc2_dma_setup(fmc2);
+	if (ret)
+		return ret;
+
+	/* FMC2 init routine */
+	stm32_fmc2_init(fmc2);
+
+	nand = &fmc2->nand;
+	chip = &nand->chip;
+	mtd = nand_to_mtd(chip);
+	mtd->dev.parent = dev;
+
+	chip->controller = &fmc2->base;
+	chip->options |= NAND_BUSWIDTH_AUTO | NAND_NO_SUBPAGE_WRITE |
+			 NAND_USE_BOUNCE_BUFFER;
+
+	/* Default ECC settings */
+	chip->ecc.mode = NAND_ECC_HW;
+	chip->ecc.size = FMC2_ECC_STEP_SIZE;
+	chip->ecc.strength = FMC2_ECC_BCH8;
+
+	/* Scan to find existence of the device */
+	ret = nand_scan(chip, nand->ncs);
+	if (ret)
+		goto err_scan;
+
+	ret = mtd_device_register(mtd, NULL, 0);
+	if (ret)
+		goto err_device_register;
+
+	platform_set_drvdata(pdev, fmc2);
+
+	return 0;
+
+err_device_register:
+	nand_cleanup(chip);
+
+err_scan:
+	if (fmc2->dma_ecc_ch)
+		dma_release_channel(fmc2->dma_ecc_ch);
+	if (fmc2->dma_tx_ch)
+		dma_release_channel(fmc2->dma_tx_ch);
+	if (fmc2->dma_rx_ch)
+		dma_release_channel(fmc2->dma_rx_ch);
+
+	sg_free_table(&fmc2->dma_data_sg);
+	sg_free_table(&fmc2->dma_ecc_sg);
+
+	clk_disable_unprepare(fmc2->clk);
+
+	return ret;
+}
+
+static int stm32_fmc2_remove(struct platform_device *pdev)
+{
+	struct stm32_fmc2_nfc *fmc2 = platform_get_drvdata(pdev);
+	struct stm32_fmc2_nand *nand = &fmc2->nand;
+
+	nand_release(&nand->chip);
+
+	if (fmc2->dma_ecc_ch)
+		dma_release_channel(fmc2->dma_ecc_ch);
+	if (fmc2->dma_tx_ch)
+		dma_release_channel(fmc2->dma_tx_ch);
+	if (fmc2->dma_rx_ch)
+		dma_release_channel(fmc2->dma_rx_ch);
+
+	sg_free_table(&fmc2->dma_data_sg);
+	sg_free_table(&fmc2->dma_ecc_sg);
+
+	clk_disable_unprepare(fmc2->clk);
+
+	return 0;
+}
+
+static int __maybe_unused stm32_fmc2_suspend(struct device *dev)
+{
+	struct stm32_fmc2_nfc *fmc2 = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(fmc2->clk);
+
+	pinctrl_pm_select_sleep_state(dev);
+
+	return 0;
+}
+
+static int __maybe_unused stm32_fmc2_resume(struct device *dev)
+{
+	struct stm32_fmc2_nfc *fmc2 = dev_get_drvdata(dev);
+	struct stm32_fmc2_nand *nand = &fmc2->nand;
+	int chip_cs, ret;
+
+	pinctrl_pm_select_default_state(dev);
+
+	ret = clk_prepare_enable(fmc2->clk);
+	if (ret) {
+		dev_err(dev, "can not enable the clock\n");
+		return ret;
+	}
+
+	stm32_fmc2_init(fmc2);
+
+	for (chip_cs = 0; chip_cs < FMC2_MAX_CE; chip_cs++) {
+		if (!(fmc2->cs_assigned & BIT(chip_cs)))
+			continue;
+
+		nand_reset(&nand->chip, chip_cs);
+	}
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(stm32_fmc2_pm_ops, stm32_fmc2_suspend,
+			 stm32_fmc2_resume);
+
+static const struct of_device_id stm32_fmc2_match[] = {
+	{.compatible = "st,stm32mp15-fmc2"},
+	{}
+};
+MODULE_DEVICE_TABLE(of, stm32_fmc2_match);
+
+static struct platform_driver stm32_fmc2_driver = {
+	.probe	= stm32_fmc2_probe,
+	.remove	= stm32_fmc2_remove,
+	.driver	= {
+		.name = "stm32_fmc2_nand",
+		.of_match_table = stm32_fmc2_match,
+		.pm = &stm32_fmc2_pm_ops,
+	},
+};
+module_platform_driver(stm32_fmc2_driver);
+
+MODULE_ALIAS("platform:stm32_fmc2_nand");
+MODULE_AUTHOR("Christophe Kerello <christophe.kerello@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics STM32 FMC2 nand driver");
+MODULE_LICENSE("GPL v2");
-- 
1.9.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [ v3 3/3] mtd: rawnand: stm32_fmc2: add manual mode
  2018-11-29 16:41 [ v3 0/3] mtd: rawnand: add STM32 FMC2 NAND flash controller driver Christophe Kerello
  2018-11-29 16:41 ` [ v3 1/3] dt-bindings: mtd: stm32_fmc2: add STM32 FMC2 NAND controller documentation Christophe Kerello
  2018-11-29 16:41 ` [ v3 2/3] mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver Christophe Kerello
@ 2018-11-29 16:41 ` Christophe Kerello
  2018-12-07  9:16   ` Linus Walleij
  2 siblings, 1 reply; 14+ messages in thread
From: Christophe Kerello @ 2018-11-29 16:41 UTC (permalink / raw)
  To: boris.brezillon, miquel.raynal, richard, dwmw2,
	computersforpeace, marek.vasut, robh+dt, mark.rutland
  Cc: linux-mtd, linux-kernel, devicetree, linux-stm32, Christophe Kerello

This patch adds the manual mode, a basic mode that do not need
any DMA channels. This mode is also useful for debug purpose.

Signed-off-by: Christophe Kerello <christophe.kerello@st.com>
---
 drivers/mtd/nand/raw/stm32_fmc2_nand.c | 329 +++++++++++++++++++++++++++++----
 1 file changed, 297 insertions(+), 32 deletions(-)

diff --git a/drivers/mtd/nand/raw/stm32_fmc2_nand.c b/drivers/mtd/nand/raw/stm32_fmc2_nand.c
index b62b052..9b8bb8f 100644
--- a/drivers/mtd/nand/raw/stm32_fmc2_nand.c
+++ b/drivers/mtd/nand/raw/stm32_fmc2_nand.c
@@ -207,6 +207,12 @@ enum stm32_fmc2_ecc {
 	FMC2_ECC_BCH8 = 8
 };
 
+enum stm32_fmc2_irq_state {
+	FMC2_IRQ_UNKNOWN = 0,
+	FMC2_IRQ_BCH,
+	FMC2_IRQ_SEQ
+};
+
 struct stm32_fmc2_timings {
 	u8 tclr;
 	u8 tar;
@@ -241,6 +247,7 @@ struct stm32_fmc2_nfc {
 	phys_addr_t io_phys_addr;
 	phys_addr_t data_phys_addr[FMC2_MAX_CE];
 	struct clk *clk;
+	u8 irq_state;
 
 	struct dma_chan *dma_tx_ch;
 	struct dma_chan *dma_rx_ch;
@@ -400,6 +407,17 @@ static void stm32_fmc2_set_buswidth_16(struct stm32_fmc2_nfc *fmc2, bool set)
 	writel_relaxed(pcr, fmc2->io_base + FMC2_PCR);
 }
 
+/* Enable/disable ECC */
+static void stm32_fmc2_set_ecc(struct stm32_fmc2_nfc *fmc2, bool enable)
+{
+	u32 pcr = readl(fmc2->io_base + FMC2_PCR);
+
+	pcr &= ~FMC2_PCR_ECCEN;
+	if (enable)
+		pcr |= FMC2_PCR_ECCEN;
+	writel(pcr, fmc2->io_base + FMC2_PCR);
+}
+
 /* Enable irq sources in case of the sequencer is used */
 static inline void stm32_fmc2_enable_seq_irq(struct stm32_fmc2_nfc *fmc2)
 {
@@ -407,6 +425,8 @@ static inline void stm32_fmc2_enable_seq_irq(struct stm32_fmc2_nfc *fmc2)
 
 	csqier |= FMC2_CSQIER_TCIE;
 
+	fmc2->irq_state = FMC2_IRQ_SEQ;
+
 	writel_relaxed(csqier, fmc2->io_base + FMC2_CSQIER);
 }
 
@@ -418,6 +438,8 @@ static inline void stm32_fmc2_disable_seq_irq(struct stm32_fmc2_nfc *fmc2)
 	csqier &= ~FMC2_CSQIER_TCIE;
 
 	writel_relaxed(csqier, fmc2->io_base + FMC2_CSQIER);
+
+	fmc2->irq_state = FMC2_IRQ_UNKNOWN;
 }
 
 /* Clear irq sources in case of the sequencer is used */
@@ -426,6 +448,68 @@ static inline void stm32_fmc2_clear_seq_irq(struct stm32_fmc2_nfc *fmc2)
 	writel_relaxed(FMC2_CSQICR_CLEAR_IRQ, fmc2->io_base + FMC2_CSQICR);
 }
 
+/* Enable irq sources in case of bch is used */
+static inline void stm32_fmc2_enable_bch_irq(struct stm32_fmc2_nfc *fmc2,
+					     int mode)
+{
+	u32 bchier = readl_relaxed(fmc2->io_base + FMC2_BCHIER);
+
+	if (mode == NAND_ECC_WRITE)
+		bchier |= FMC2_BCHIER_EPBRIE;
+	else
+		bchier |= FMC2_BCHIER_DERIE;
+
+	fmc2->irq_state = FMC2_IRQ_BCH;
+
+	writel_relaxed(bchier, fmc2->io_base + FMC2_BCHIER);
+}
+
+/* Disable irq sources in case of bch is used */
+static inline void stm32_fmc2_disable_bch_irq(struct stm32_fmc2_nfc *fmc2)
+{
+	u32 bchier = readl_relaxed(fmc2->io_base + FMC2_BCHIER);
+
+	bchier &= ~FMC2_BCHIER_DERIE;
+	bchier &= ~FMC2_BCHIER_EPBRIE;
+
+	writel_relaxed(bchier, fmc2->io_base + FMC2_BCHIER);
+
+	fmc2->irq_state = FMC2_IRQ_UNKNOWN;
+}
+
+/* Clear irq sources in case of bch is used */
+static inline void stm32_fmc2_clear_bch_irq(struct stm32_fmc2_nfc *fmc2)
+{
+	writel_relaxed(FMC2_BCHICR_CLEAR_IRQ, fmc2->io_base + FMC2_BCHICR);
+}
+
+/*
+ * Enable ECC logic and reset syndrome/parity bits previously calculated
+ * Syndrome/parity bits is cleared by setting the ECCEN bit to 0
+ */
+static void stm32_fmc2_hwctl(struct nand_chip *chip, int mode)
+{
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+
+	stm32_fmc2_set_ecc(fmc2, false);
+
+	if (chip->ecc.strength != FMC2_ECC_HAM) {
+		u32 pcr = readl_relaxed(fmc2->io_base + FMC2_PCR);
+
+		if (mode == NAND_ECC_WRITE)
+			pcr |= FMC2_PCR_WEN;
+		else
+			pcr &= ~FMC2_PCR_WEN;
+		writel_relaxed(pcr, fmc2->io_base + FMC2_PCR);
+
+		reinit_completion(&fmc2->complete);
+		stm32_fmc2_clear_bch_irq(fmc2);
+		stm32_fmc2_enable_bch_irq(fmc2, mode);
+	}
+
+	stm32_fmc2_set_ecc(fmc2, true);
+}
+
 /*
  * ECC Hamming calculation
  * ECC is 3 bytes for 512 bytes of data (supports error correction up to
@@ -438,6 +522,30 @@ static inline void stm32_fmc2_ham_set_ecc(const u32 ecc_sta, u8 *ecc)
 	ecc[2] = ecc_sta >> 16;
 }
 
+static int stm32_fmc2_ham_calculate(struct nand_chip *chip, const u8 *data,
+				    u8 *ecc)
+{
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+	u32 sr, heccr;
+	int ret;
+
+	ret = readl_relaxed_poll_timeout(fmc2->io_base + FMC2_SR,
+					 sr, sr & FMC2_SR_NWRF, 10, 1000);
+	if (ret) {
+		dev_err(fmc2->dev, "ham timeout\n");
+		return ret;
+	}
+
+	heccr = readl_relaxed(fmc2->io_base + FMC2_HECCR);
+
+	stm32_fmc2_ham_set_ecc(heccr, ecc);
+
+	/* Disable ECC */
+	stm32_fmc2_set_ecc(fmc2, false);
+
+	return 0;
+}
+
 static int stm32_fmc2_ham_correct(struct nand_chip *chip, u8 *dat,
 				  u8 *read_ecc, u8 *calc_ecc)
 {
@@ -490,6 +598,56 @@ static int stm32_fmc2_ham_correct(struct nand_chip *chip, u8 *dat,
 	return 1;
 }
 
+/*
+ * ECC BCH calculation and correction
+ * ECC is 7/13 bytes for 512 bytes of data (supports error correction up to
+ * max of 4-bit/8-bit)
+ */
+static int stm32_fmc2_bch_calculate(struct nand_chip *chip, const u8 *data,
+				    u8 *ecc)
+{
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+	u32 bchpbr;
+
+	/* Wait until the BCH code is ready */
+	if (!wait_for_completion_timeout(&fmc2->complete,
+					 msecs_to_jiffies(1000))) {
+		dev_err(fmc2->dev, "bch timeout\n");
+		stm32_fmc2_disable_bch_irq(fmc2);
+		return -ETIMEDOUT;
+	}
+
+	/* Read parity bits */
+	bchpbr = readl_relaxed(fmc2->io_base + FMC2_BCHPBR1);
+	ecc[0] = bchpbr;
+	ecc[1] = bchpbr >> 8;
+	ecc[2] = bchpbr >> 16;
+	ecc[3] = bchpbr >> 24;
+
+	bchpbr = readl_relaxed(fmc2->io_base + FMC2_BCHPBR2);
+	ecc[4] = bchpbr;
+	ecc[5] = bchpbr >> 8;
+	ecc[6] = bchpbr >> 16;
+
+	if (chip->ecc.strength == FMC2_ECC_BCH8) {
+		ecc[7] = bchpbr >> 24;
+
+		bchpbr = readl_relaxed(fmc2->io_base + FMC2_BCHPBR3);
+		ecc[8] = bchpbr;
+		ecc[9] = bchpbr >> 8;
+		ecc[10] = bchpbr >> 16;
+		ecc[11] = bchpbr >> 24;
+
+		bchpbr = readl_relaxed(fmc2->io_base + FMC2_BCHPBR4);
+		ecc[12] = bchpbr;
+	}
+
+	/* Disable ECC */
+	stm32_fmc2_set_ecc(fmc2, false);
+
+	return 0;
+}
+
 /* BCH algorithm correction */
 static int stm32_fmc2_bch_decode(int eccsize, u8 *dat, u32 *ecc_sta)
 {
@@ -530,6 +688,94 @@ static int stm32_fmc2_bch_decode(int eccsize, u8 *dat, u32 *ecc_sta)
 	return nb_errs;
 }
 
+static int stm32_fmc2_bch_correct(struct nand_chip *chip, u8 *dat,
+				  u8 *read_ecc, u8 *calc_ecc)
+{
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+	u32 ecc_sta[5];
+
+	/* Wait until the decoding error is ready */
+	if (!wait_for_completion_timeout(&fmc2->complete,
+					 msecs_to_jiffies(1000))) {
+		dev_err(fmc2->dev, "bch timeout\n");
+		stm32_fmc2_disable_bch_irq(fmc2);
+		return -ETIMEDOUT;
+	}
+
+	ecc_sta[0] = readl_relaxed(fmc2->io_base + FMC2_BCHDSR0);
+	ecc_sta[1] = readl_relaxed(fmc2->io_base + FMC2_BCHDSR1);
+	ecc_sta[2] = readl_relaxed(fmc2->io_base + FMC2_BCHDSR2);
+	ecc_sta[3] = readl_relaxed(fmc2->io_base + FMC2_BCHDSR3);
+	ecc_sta[4] = readl_relaxed(fmc2->io_base + FMC2_BCHDSR4);
+
+	/* Disable ECC */
+	stm32_fmc2_set_ecc(fmc2, false);
+
+	return stm32_fmc2_bch_decode(chip->ecc.size, dat, ecc_sta);
+}
+
+static int stm32_fmc2_read_page(struct nand_chip *chip, u8 *buf,
+				int oob_required, int page)
+{
+	struct mtd_info *mtd = nand_to_mtd(chip);
+	int ret, i, s, stat, eccsize = chip->ecc.size;
+	int eccbytes = chip->ecc.bytes;
+	int eccsteps = chip->ecc.steps;
+	int eccstrength = chip->ecc.strength;
+	u8 *p = buf;
+	u8 *ecc_calc = chip->ecc.calc_buf;
+	u8 *ecc_code = chip->ecc.code_buf;
+	unsigned int max_bitflips = 0;
+
+	ret = nand_read_page_op(chip, page, 0, NULL, 0);
+	if (ret)
+		return ret;
+
+	for (i = mtd->writesize + FMC2_BBM_LEN, s = 0; s < eccsteps;
+	     s++, i += eccbytes, p += eccsize) {
+		chip->ecc.hwctl(chip, NAND_ECC_READ);
+
+		/* Read the nand page sector (512 bytes) */
+		ret = nand_change_read_column_op(chip, s * eccsize, p,
+						 eccsize, false);
+		if (ret)
+			return ret;
+
+		/* Read the corresponding ECC bytes */
+		ret = nand_change_read_column_op(chip, i, ecc_code,
+						 eccbytes, false);
+		if (ret)
+			return ret;
+
+		/* Correct the data */
+		stat = chip->ecc.correct(chip, p, ecc_code, ecc_calc);
+		if (stat == -EBADMSG)
+			/* Check for empty pages with bitflips */
+			stat = nand_check_erased_ecc_chunk(p, eccsize,
+							   ecc_code, eccbytes,
+							   NULL, 0,
+							   eccstrength);
+
+		if (stat < 0) {
+			mtd->ecc_stats.failed++;
+		} else {
+			mtd->ecc_stats.corrected += stat;
+			max_bitflips = max_t(unsigned int, max_bitflips, stat);
+		}
+	}
+
+	/* Read oob */
+	if (oob_required) {
+		ret = nand_change_read_column_op(chip, mtd->writesize,
+						 chip->oob_poi, mtd->oobsize,
+						 false);
+		if (ret)
+			return ret;
+	}
+
+	return max_bitflips;
+}
+
 /* Sequencer read/write configuration */
 static void stm32_fmc2_rw_page_init(struct nand_chip *chip, int page,
 				    int raw, bool write_data)
@@ -967,7 +1213,12 @@ static irqreturn_t stm32_fmc2_irq(int irq, void *dev_id)
 {
 	struct stm32_fmc2_nfc *fmc2 = (struct stm32_fmc2_nfc *)dev_id;
 
-	stm32_fmc2_disable_seq_irq(fmc2);
+	if (fmc2->irq_state == FMC2_IRQ_SEQ)
+		/* Sequencer is used */
+		stm32_fmc2_disable_seq_irq(fmc2);
+	else if (fmc2->irq_state == FMC2_IRQ_BCH)
+		/* BCH is used */
+		stm32_fmc2_disable_bch_irq(fmc2);
 
 	complete(&fmc2->complete);
 
@@ -1356,35 +1607,27 @@ static int stm32_fmc2_dma_setup(struct stm32_fmc2_nfc *fmc2)
 	fmc2->dma_rx_ch = dma_request_slave_channel(fmc2->dev, "rx");
 	fmc2->dma_ecc_ch = dma_request_slave_channel(fmc2->dev, "ecc");
 
-	if (fmc2->dma_ecc_ch) {
-		ret = sg_alloc_table(&fmc2->dma_ecc_sg, FMC2_MAX_SG,
-				     GFP_KERNEL);
-		if (ret)
-			return ret;
-
-		/* Allocate a buffer to store ECC status registers */
-		fmc2->ecc_buf = devm_kzalloc(fmc2->dev,
-					     FMC2_MAX_ECC_BUF_LEN,
-					     GFP_KERNEL);
-		if (!fmc2->ecc_buf)
-			return -ENOMEM;
-	} else {
-		dev_err(fmc2->dev, "ECC DMA not defined in the device tree\n");
-		return -ENOENT;
+	if (!fmc2->dma_tx_ch || !fmc2->dma_rx_ch || !fmc2->dma_ecc_ch) {
+		dev_warn(fmc2->dev, "DMAs not defined in the device tree, manual mode is used\n");
+		return 0;
 	}
 
-	if (fmc2->dma_tx_ch && fmc2->dma_rx_ch) {
-		ret = sg_alloc_table(&fmc2->dma_data_sg, FMC2_MAX_SG,
+	ret = sg_alloc_table(&fmc2->dma_ecc_sg, FMC2_MAX_SG, GFP_KERNEL);
+	if (ret)
+		return ret;
+
+	/* Allocate a buffer to store ECC status registers */
+	fmc2->ecc_buf = devm_kzalloc(fmc2->dev, FMC2_MAX_ECC_BUF_LEN,
 				     GFP_KERNEL);
-		if (ret)
-			return ret;
+	if (!fmc2->ecc_buf)
+		return -ENOMEM;
 
-		init_completion(&fmc2->dma_data_complete);
-		init_completion(&fmc2->dma_ecc_complete);
-	} else {
-		dev_err(fmc2->dev, "rx/tx DMA not defined in the device tree\n");
-		return -ENOENT;
-	}
+	ret = sg_alloc_table(&fmc2->dma_data_sg, FMC2_MAX_SG, GFP_KERNEL);
+	if (ret)
+		return ret;
+
+	init_completion(&fmc2->dma_data_complete);
+	init_completion(&fmc2->dma_ecc_complete);
 
 	return 0;
 }
@@ -1392,12 +1635,34 @@ static int stm32_fmc2_dma_setup(struct stm32_fmc2_nfc *fmc2)
 /* NAND callbacks setup */
 static void stm32_fmc2_nand_callbacks_setup(struct nand_chip *chip)
 {
-	/* Specific callbacks to read/write a page */
-	chip->ecc.correct = stm32_fmc2_sequencer_correct;
-	chip->ecc.write_page = stm32_fmc2_sequencer_write_page;
-	chip->ecc.read_page = stm32_fmc2_sequencer_read_page;
-	chip->ecc.write_page_raw = stm32_fmc2_sequencer_write_page_raw;
-	chip->ecc.read_page_raw = stm32_fmc2_sequencer_read_page_raw;
+	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
+
+	/*
+	 * Specific callbacks to read/write a page depending on
+	 * the mode (manual/sequencer) and the algo used (Hamming, BCH).
+	 */
+	if (fmc2->dma_tx_ch && fmc2->dma_rx_ch && fmc2->dma_ecc_ch) {
+		/* DMA => use sequencer mode callbacks */
+		chip->ecc.correct = stm32_fmc2_sequencer_correct;
+		chip->ecc.write_page = stm32_fmc2_sequencer_write_page;
+		chip->ecc.read_page = stm32_fmc2_sequencer_read_page;
+		chip->ecc.write_page_raw = stm32_fmc2_sequencer_write_page_raw;
+		chip->ecc.read_page_raw = stm32_fmc2_sequencer_read_page_raw;
+	} else {
+		/* No DMA => use manual mode callbacks */
+		chip->ecc.hwctl = stm32_fmc2_hwctl;
+		if (chip->ecc.strength == FMC2_ECC_HAM) {
+			/* Hamming is used */
+			chip->ecc.calculate = stm32_fmc2_ham_calculate;
+			chip->ecc.correct = stm32_fmc2_ham_correct;
+			chip->ecc.options |= NAND_ECC_GENERIC_ERASED_CHECK;
+		} else {
+			/* BCH is used */
+			chip->ecc.calculate = stm32_fmc2_bch_calculate;
+			chip->ecc.correct = stm32_fmc2_bch_correct;
+			chip->ecc.read_page = stm32_fmc2_read_page;
+		}
+	}
 
 	/* Specific configurations depending on the algo used */
 	if (chip->ecc.strength == FMC2_ECC_HAM)
-- 
1.9.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* Re: [ v3 2/3] mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver
  2018-11-29 16:41 ` [ v3 2/3] mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver Christophe Kerello
@ 2018-12-07  9:06   ` Linus Walleij
  2018-12-07 10:21     ` [Linux-stm32] " Benjamin GAIGNARD
  2018-12-07 16:53     ` Christophe Kerello
  2018-12-07 10:18   ` Miquel Raynal
  1 sibling, 2 replies; 14+ messages in thread
From: Linus Walleij @ 2018-12-07  9:06 UTC (permalink / raw)
  To: christophe.kerello
  Cc: Boris Brezillon, Miquèl Raynal, Richard Weinberger,
	David Woodhouse, Brian Norris, Mark Vasut, Rob Herring,
	Mark Rutland, linux-mtd, linux-kernel,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	linux-stm32

Hi Christophe,

On Thu, Nov 29, 2018 at 5:42 PM Christophe Kerello
<christophe.kerello@st.com> wrote:

> +/* FMC2 Controller Registers */
> +#define FMC2_BCR1                      0x0
> +#define FMC2_PCR                       0x80
(...)
> +/* Register: FMC2_BCR1 */
> +#define FMC2_BCR1_FMC2EN               BIT(31)

Well this looks like an especially clever register map and a specific choice
of bit 31 in the fist register to activate FMC2. Registers 0x04 thru
0x7c are completely unused save for one bit.

It's almost like this is the good old FSMC integrated in parallel with FMC2,
so that if you don't set bit 31, this becomes something that can be used
with drivers/mtd/nand/raw/fsmc_nand.c, and FMC2 mode is activated
by setting this bit, activating all the new registers.

It wouldn't surprise me given how HW designers like to work.

Is this the case?

If that is the case I think it should at least be mentioned in commit
logs and DT bindings and possibly in a comment on the driver
itself.

Yours,
Linus Walleij

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [ v3 3/3] mtd: rawnand: stm32_fmc2: add manual mode
  2018-11-29 16:41 ` [ v3 3/3] mtd: rawnand: stm32_fmc2: add manual mode Christophe Kerello
@ 2018-12-07  9:16   ` Linus Walleij
  2018-12-07 10:56     ` Christophe Kerello
  0 siblings, 1 reply; 14+ messages in thread
From: Linus Walleij @ 2018-12-07  9:16 UTC (permalink / raw)
  To: christophe.kerello
  Cc: Boris Brezillon, Miquèl Raynal, Richard Weinberger,
	David Woodhouse, Brian Norris, Mark Vasut, Rob Herring,
	Mark Rutland, linux-mtd, linux-kernel,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	linux-stm32

On Thu, Nov 29, 2018 at 5:42 PM Christophe Kerello
<christophe.kerello@st.com> wrote:

> This patch adds the manual mode, a basic mode that do not need
> any DMA channels. This mode is also useful for debug purpose.
>
> Signed-off-by: Christophe Kerello <christophe.kerello@st.com>

This is a bit of drive-by comment, but "manual mode" usually
means there is a person "a man" pulling levers and pushing
buttons. There is nothing manual inside a computer system.

I think the more appropriate term is "polling mode" which is
what we call code that read registers directly waiting for status
flags rather than relying on IRQs or DMA flows.

Yours,
Linus Walleij

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [ v3 2/3] mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver
  2018-11-29 16:41 ` [ v3 2/3] mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver Christophe Kerello
  2018-12-07  9:06   ` Linus Walleij
@ 2018-12-07 10:18   ` Miquel Raynal
  2018-12-07 10:53     ` Christophe Kerello
  1 sibling, 1 reply; 14+ messages in thread
From: Miquel Raynal @ 2018-12-07 10:18 UTC (permalink / raw)
  To: Christophe Kerello
  Cc: boris.brezillon, richard, dwmw2, computersforpeace, marek.vasut,
	robh+dt, mark.rutland, linux-mtd, linux-kernel, devicetree,
	linux-stm32

Hi Christophe,

Christophe Kerello <christophe.kerello@st.com> wrote on Thu, 29 Nov
2018 17:41:02 +0100:

> The driver adds the support for the STMicroelectronics FMC2 NAND
> Controller found on STM32MP SOCs.
> 
> This patch is based on FMC2 command sequencer.
> The purpose of the command sequencer is to facilitate the programming
> and the reading of NAND flash pages with the ECC and to free the CPU
> of sequencing tasks.
> It requires one DMA channel for write and two DMA channels for read
> operations.
> 
> Only NAND_ECC_HW mode is actually supported.
> The driver supports a maximum 8k page size.
> The following ECC strength and step size are currently supported:
>  - nand-ecc-strength = <8>, nand-ecc-step-size = <512> (BCH8)
>  - nand-ecc-strength = <4>, nand-ecc-step-size = <512> (BCH4)
>  - nand-ecc-strength = <1>, nand-ecc-step-size = <512> (Extended ECC
>    based on Hamming)
> 
> This patch has been tested on Micron MT29F8G08ABACAH4 and
> MT29F8G16ABACAH4
> 
> Signed-off-by: Christophe Kerello <christophe.kerello@st.com>
> ---

The driver look's good to me. However, Boris contributed new
cleanups that I would like you to take into account before doing
another 'deep' review. Please rebase on top of nand/next and have
a look at the followingcommits. For the ->select_chip() hook, it
should not be exposed anymore and switches should be handled
locally by the driver (you have examples).

7a08dbaedd36 mtd: rawnand: Move ->setup_data_interface() to nand_controller_ops
f2abfeb2078b mtd: rawnand: Move the ->exec_op() method to nand_controller_ops
7d6c37e90cf9 mtd: rawnand: Deprecate the ->select_chip() hook
1770022ffa85 mtd: rawnand: ams-delta: Stop implementing ->select_chip()
653c57c7da08 mtd: rawnand: vf610: Stop implementing ->select_chip()
2ace451cae22 mtd: rawnand: tegra: Stop implementing ->select_chip()
b25251414f6e mtd: rawnand: marvell: Stop implementing ->select_chip()
550b9fc4e3af mtd: rawnand: fsmc: Stop implementing ->select_chip()
02b4a52604a4 mtd: rawnand: Make ->select_chip() optional when ->exec_op() is implemented
ae2294b10b0f mtd: rawnand: Pass the CS line to be selected in struct nand_operation
1d0178593d14 mtd: rawnand: Add nand_[de]select_target() helpers

While at it, could you also address Linus W. comments.

Thanks,
Miquèl

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [Linux-stm32] [ v3 2/3] mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver
  2018-12-07  9:06   ` Linus Walleij
@ 2018-12-07 10:21     ` Benjamin GAIGNARD
  2018-12-07 12:47       ` Linus Walleij
  2018-12-07 16:53     ` Christophe Kerello
  1 sibling, 1 reply; 14+ messages in thread
From: Benjamin GAIGNARD @ 2018-12-07 10:21 UTC (permalink / raw)
  To: Linus Walleij, Christophe KERELLO
  Cc: Mark Rutland,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	Boris Brezillon, Richard Weinberger, linux-kernel, Mark Vasut,
	Rob Herring, linux-mtd, Miquèl Raynal, Brian Norris,
	David Woodhouse, linux-stm32


On 12/7/18 10:06 AM, Linus Walleij wrote:
> Hi Christophe,
>
> On Thu, Nov 29, 2018 at 5:42 PM Christophe Kerello
> <christophe.kerello@st.com> wrote:
>
>> +/* FMC2 Controller Registers */
>> +#define FMC2_BCR1                      0x0
>> +#define FMC2_PCR                       0x80
> (...)
>> +/* Register: FMC2_BCR1 */
>> +#define FMC2_BCR1_FMC2EN               BIT(31)
> Well this looks like an especially clever register map and a specific choice
> of bit 31 in the fist register to activate FMC2. Registers 0x04 thru
> 0x7c are completely unused save for one bit.
>
> It's almost like this is the good old FSMC integrated in parallel with FMC2,
> so that if you don't set bit 31, this becomes something that can be used
> with drivers/mtd/nand/raw/fsmc_nand.c, and FMC2 mode is activated
> by setting this bit, activating all the new registers.
>
> It wouldn't surprise me given how HW designers like to work.
>
> Is this the case?

No, it is the same story than for stmfx driver, it looks to be the same 
from registers

point of view but internal hardware block design is completely different.

>
> If that is the case I think it should at least be mentioned in commit
> logs and DT bindings and possibly in a comment on the driver
> itself.
>
> Yours,
> Linus Walleij
> _______________________________________________
> Linux-stm32 mailing list
> Linux-stm32@st-md-mailman.stormreply.com
> https://st-md-mailman.stormreply.com/mailman/listinfo/linux-stm32

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [ v3 2/3] mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver
  2018-12-07 10:18   ` Miquel Raynal
@ 2018-12-07 10:53     ` Christophe Kerello
  0 siblings, 0 replies; 14+ messages in thread
From: Christophe Kerello @ 2018-12-07 10:53 UTC (permalink / raw)
  To: Miquel Raynal
  Cc: boris.brezillon, richard, dwmw2, computersforpeace, marek.vasut,
	robh+dt, mark.rutland, linux-mtd, linux-kernel, devicetree,
	linux-stm32

Hi Miquèl,

This patchset already takes into account new framework modifications 
done by Boris (3rd batch of cleanups).

The select_chip hook is not used any more in this patchset and 
exec_op/setup_data_interface hooks have been moved to 
nand_controller_ops structure.

static const struct nand_controller_ops stm32_fmc2_nand_controller_ops = {
	.attach_chip = stm32_fmc2_attach_chip,
	.exec_op = stm32_fmc2_exec_op,
	.setup_data_interface = stm32_fmc2_setup_interface,
};

Regards,
Christophe Kerello.

On 12/7/18 11:18 AM, Miquel Raynal wrote:
> Hi Christophe,
> 
> Christophe Kerello <christophe.kerello@st.com> wrote on Thu, 29 Nov
> 2018 17:41:02 +0100:
> 
>> The driver adds the support for the STMicroelectronics FMC2 NAND
>> Controller found on STM32MP SOCs.
>>
>> This patch is based on FMC2 command sequencer.
>> The purpose of the command sequencer is to facilitate the programming
>> and the reading of NAND flash pages with the ECC and to free the CPU
>> of sequencing tasks.
>> It requires one DMA channel for write and two DMA channels for read
>> operations.
>>
>> Only NAND_ECC_HW mode is actually supported.
>> The driver supports a maximum 8k page size.
>> The following ECC strength and step size are currently supported:
>>   - nand-ecc-strength = <8>, nand-ecc-step-size = <512> (BCH8)
>>   - nand-ecc-strength = <4>, nand-ecc-step-size = <512> (BCH4)
>>   - nand-ecc-strength = <1>, nand-ecc-step-size = <512> (Extended ECC
>>     based on Hamming)
>>
>> This patch has been tested on Micron MT29F8G08ABACAH4 and
>> MT29F8G16ABACAH4
>>
>> Signed-off-by: Christophe Kerello <christophe.kerello@st.com>
>> ---
> 
> The driver look's good to me. However, Boris contributed new
> cleanups that I would like you to take into account before doing
> another 'deep' review. Please rebase on top of nand/next and have
> a look at the followingcommits. For the ->select_chip() hook, it
> should not be exposed anymore and switches should be handled
> locally by the driver (you have examples).
> 
> 7a08dbaedd36 mtd: rawnand: Move ->setup_data_interface() to nand_controller_ops
> f2abfeb2078b mtd: rawnand: Move the ->exec_op() method to nand_controller_ops
> 7d6c37e90cf9 mtd: rawnand: Deprecate the ->select_chip() hook
> 1770022ffa85 mtd: rawnand: ams-delta: Stop implementing ->select_chip()
> 653c57c7da08 mtd: rawnand: vf610: Stop implementing ->select_chip()
> 2ace451cae22 mtd: rawnand: tegra: Stop implementing ->select_chip()
> b25251414f6e mtd: rawnand: marvell: Stop implementing ->select_chip()
> 550b9fc4e3af mtd: rawnand: fsmc: Stop implementing ->select_chip()
> 02b4a52604a4 mtd: rawnand: Make ->select_chip() optional when ->exec_op() is implemented
> ae2294b10b0f mtd: rawnand: Pass the CS line to be selected in struct nand_operation
> 1d0178593d14 mtd: rawnand: Add nand_[de]select_target() helpers
> 
> While at it, could you also address Linus W. comments.
> 
> Thanks,
> Miquèl
> 

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [ v3 3/3] mtd: rawnand: stm32_fmc2: add manual mode
  2018-12-07  9:16   ` Linus Walleij
@ 2018-12-07 10:56     ` Christophe Kerello
  0 siblings, 0 replies; 14+ messages in thread
From: Christophe Kerello @ 2018-12-07 10:56 UTC (permalink / raw)
  To: Linus Walleij
  Cc: Boris Brezillon, Miquèl Raynal, Richard Weinberger,
	David Woodhouse, Brian Norris, Mark Vasut, Rob Herring,
	Mark Rutland, linux-mtd, linux-kernel,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	linux-stm32

Hi Linus,

It is correct.
I will replace "manual mode" by "polling mode" in next patchset.

Regards,
Christophe Kerello.

On 12/7/18 10:16 AM, Linus Walleij wrote:
> On Thu, Nov 29, 2018 at 5:42 PM Christophe Kerello
> <christophe.kerello@st.com> wrote:
> 
>> This patch adds the manual mode, a basic mode that do not need
>> any DMA channels. This mode is also useful for debug purpose.
>>
>> Signed-off-by: Christophe Kerello <christophe.kerello@st.com>
> 
> This is a bit of drive-by comment, but "manual mode" usually
> means there is a person "a man" pulling levers and pushing
> buttons. There is nothing manual inside a computer system.
> 
> I think the more appropriate term is "polling mode" which is
> what we call code that read registers directly waiting for status
> flags rather than relying on IRQs or DMA flows.
> 
> Yours,
> Linus Walleij
> 

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [Linux-stm32] [ v3 2/3] mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver
  2018-12-07 10:21     ` [Linux-stm32] " Benjamin GAIGNARD
@ 2018-12-07 12:47       ` Linus Walleij
  0 siblings, 0 replies; 14+ messages in thread
From: Linus Walleij @ 2018-12-07 12:47 UTC (permalink / raw)
  To: Benjamin Gaignard
  Cc: christophe.kerello, Mark Rutland,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	Boris Brezillon, Richard Weinberger, linux-kernel, Mark Vasut,
	Rob Herring, linux-mtd, Miquèl Raynal, Brian Norris,
	David Woodhouse, linux-stm32

On Fri, Dec 7, 2018 at 11:22 AM Benjamin GAIGNARD
<benjamin.gaignard@st.com> wrote:
> On 12/7/18 10:06 AM, Linus Walleij wrote:
> > Hi Christophe,
> >
> > On Thu, Nov 29, 2018 at 5:42 PM Christophe Kerello
> > <christophe.kerello@st.com> wrote:
> >
> >> +/* FMC2 Controller Registers */
> >> +#define FMC2_BCR1                      0x0
> >> +#define FMC2_PCR                       0x80
> > (...)
> >> +/* Register: FMC2_BCR1 */
> >> +#define FMC2_BCR1_FMC2EN               BIT(31)
> > Well this looks like an especially clever register map and a specific choice
> > of bit 31 in the fist register to activate FMC2. Registers 0x04 thru
> > 0x7c are completely unused save for one bit.
> >
> > It's almost like this is the good old FSMC integrated in parallel with FMC2,
> > so that if you don't set bit 31, this becomes something that can be used
> > with drivers/mtd/nand/raw/fsmc_nand.c, and FMC2 mode is activated
> > by setting this bit, activating all the new registers.
> >
> > It wouldn't surprise me given how HW designers like to work.
> >
> > Is this the case?
>
> No, it is the same story than for stmfx driver, it looks to be the same
> from registers
>
> point of view but internal hardware block design is completely different.

I'm not saying FMC2 is the same, just that it seems they have
duct-taped both IP-blocks (FSMC and FMC2) together at some point.

It just looks so extremely odd to leave all registers below 0x80 unused
except for 0x0 where a single bit is used.

Maybe there is no FSMC there, but it sure looks like the hardware
engineers planned for old+new FSM[C] block coexistence in the
same address space.

Yours,
Linus Walleij

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [ v3 2/3] mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver
  2018-12-07  9:06   ` Linus Walleij
  2018-12-07 10:21     ` [Linux-stm32] " Benjamin GAIGNARD
@ 2018-12-07 16:53     ` Christophe Kerello
  2018-12-13 10:45       ` Linus Walleij
  1 sibling, 1 reply; 14+ messages in thread
From: Christophe Kerello @ 2018-12-07 16:53 UTC (permalink / raw)
  To: Linus Walleij
  Cc: Boris Brezillon, Miquèl Raynal, Richard Weinberger,
	David Woodhouse, Brian Norris, Mark Vasut, Rob Herring,
	Mark Rutland, linux-mtd, linux-kernel,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	linux-stm32

On 12/7/18 10:06 AM, Linus Walleij wrote:
> Hi Christophe,
> 
> On Thu, Nov 29, 2018 at 5:42 PM Christophe Kerello
> <christophe.kerello@st.com> wrote:
> 
>> +/* FMC2 Controller Registers */
>> +#define FMC2_BCR1                      0x0
>> +#define FMC2_PCR                       0x80
> (...)
>> +/* Register: FMC2_BCR1 */
>> +#define FMC2_BCR1_FMC2EN               BIT(31)
> 
> Well this looks like an especially clever register map and a specific choice
> of bit 31 in the fist register to activate FMC2. Registers 0x04 thru
> 0x7c are completely unused save for one bit.
> 
> It's almost like this is the good old FSMC integrated in parallel with FMC2,
> so that if you don't set bit 31, this becomes something that can be used
> with drivers/mtd/nand/raw/fsmc_nand.c, and FMC2 mode is activated
> by setting this bit, activating all the new registers.
> 
> It wouldn't surprise me given how HW designers like to work.
> 
> Is this the case?
> 

Hi Linus,

Based on FMC2 datasheet,
The FMC2 controller includes 2 memory controllers:
  - the NOR/PSRAM memory controller
  - the NAND memory controller

The NOR/PSRAM controller mapping is starting at 0.
The NAND controller mapping is starting at 0x80.

We have only planned to develop a driver for the NAND memory controller.
There is currently no customer request to develop the NOR/PSRAM memory 
controller.

The bit FMC2_BCR1_FMC2EN is not used to switch from an IP version to 
another. After reset, the FMC2 controller is disabled. Once all the used 
memory controllers are configured, the FMC2 controller must be enabled 
by setting the FMC2EN bit in the FMC2_BCR1 register. If this bit is not 
set, the controller stays in disabled state.

Regards,
Christophe Kerello.

> If that is the case I think it should at least be mentioned in commit
> logs and DT bindings and possibly in a comment on the driver
> itself.
> 
> Yours,
> Linus Walleij
> 

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [ v3 1/3] dt-bindings: mtd: stm32_fmc2: add STM32 FMC2 NAND controller documentation
  2018-11-29 16:41 ` [ v3 1/3] dt-bindings: mtd: stm32_fmc2: add STM32 FMC2 NAND controller documentation Christophe Kerello
@ 2018-12-07 23:42   ` Rob Herring
  0 siblings, 0 replies; 14+ messages in thread
From: Rob Herring @ 2018-12-07 23:42 UTC (permalink / raw)
  To: Christophe Kerello
  Cc: boris.brezillon, miquel.raynal, richard, dwmw2,
	computersforpeace, marek.vasut, robh+dt, mark.rutland, linux-mtd,
	linux-kernel, devicetree, linux-stm32, Christophe Kerello

On Thu, 29 Nov 2018 17:41:01 +0100, Christophe Kerello wrote:
> This patch adds the documentation of the device tree bindings for the STM32
> FMC2 NAND controller.
> 
> Signed-off-by: Christophe Kerello <christophe.kerello@st.com>
> ---
>  .../devicetree/bindings/mtd/stm32-fmc2-nand.txt    | 61 ++++++++++++++++++++++
>  1 file changed, 61 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mtd/stm32-fmc2-nand.txt
> 

Reviewed-by: Rob Herring <robh@kernel.org>

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [ v3 2/3] mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver
  2018-12-07 16:53     ` Christophe Kerello
@ 2018-12-13 10:45       ` Linus Walleij
  0 siblings, 0 replies; 14+ messages in thread
From: Linus Walleij @ 2018-12-13 10:45 UTC (permalink / raw)
  To: christophe.kerello
  Cc: Boris Brezillon, Miquèl Raynal, Richard Weinberger,
	David Woodhouse, Brian Norris, Mark Vasut, Rob Herring,
	Mark Rutland, linux-mtd, linux-kernel,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	linux-stm32

On Fri, Dec 7, 2018 at 5:53 PM Christophe Kerello
<christophe.kerello@st.com> wrote:
> On 12/7/18 10:06 AM, Linus Walleij wrote:

> Based on FMC2 datasheet,
> The FMC2 controller includes 2 memory controllers:
>   - the NOR/PSRAM memory controller
>   - the NAND memory controller
>
> The NOR/PSRAM controller mapping is starting at 0.
> The NAND controller mapping is starting at 0x80.
>
> We have only planned to develop a driver for the NAND memory controller.
> There is currently no customer request to develop the NOR/PSRAM memory
> controller.

OK I get it, so there is no FSMC (v1), but a NOR controller, thanks!

If people need to access the NOR controller I think they can just patch
your driver to handle both or have a second driver on the side
(I suspect the pins are anyways set up such that you can just
use either NOR or NAND.)

Yours,
Linus Walleij

^ permalink raw reply	[flat|nested] 14+ messages in thread

end of thread, other threads:[~2018-12-13 10:45 UTC | newest]

Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-11-29 16:41 [ v3 0/3] mtd: rawnand: add STM32 FMC2 NAND flash controller driver Christophe Kerello
2018-11-29 16:41 ` [ v3 1/3] dt-bindings: mtd: stm32_fmc2: add STM32 FMC2 NAND controller documentation Christophe Kerello
2018-12-07 23:42   ` Rob Herring
2018-11-29 16:41 ` [ v3 2/3] mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver Christophe Kerello
2018-12-07  9:06   ` Linus Walleij
2018-12-07 10:21     ` [Linux-stm32] " Benjamin GAIGNARD
2018-12-07 12:47       ` Linus Walleij
2018-12-07 16:53     ` Christophe Kerello
2018-12-13 10:45       ` Linus Walleij
2018-12-07 10:18   ` Miquel Raynal
2018-12-07 10:53     ` Christophe Kerello
2018-11-29 16:41 ` [ v3 3/3] mtd: rawnand: stm32_fmc2: add manual mode Christophe Kerello
2018-12-07  9:16   ` Linus Walleij
2018-12-07 10:56     ` Christophe Kerello

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