[RFC PATCH 1/2] spi: dt-bindings: add Siflower Quad SPI controller

[RFC PATCH 1/2] spi: dt-bindings: add Siflower Quad SPI controller

[Qingfang Deng]

From: Qingfang Deng <qingfang.deng@siflower.com.cn>

Add YAML devicetree bindings for Siflower Quad SPI controller.

Signed-off-by: Qingfang Deng <qingfang.deng@siflower.com.cn>
---
 .../bindings/spi/siflower,qspi.yaml           | 54 +++++++++++++++++++
 1 file changed, 54 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/spi/siflower,qspi.yaml

diff --git a/Documentation/devicetree/bindings/spi/siflower,qspi.yaml b/Documentation/devicetree/bindings/spi/siflower,qspi.yaml
new file mode 100644
index 000000000000..c2dbe82affc2
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/siflower,qspi.yaml
@@ -0,0 +1,54 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/spi/siflower,qspi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Siflower Quad Serial Peripheral Interface (QSPI)
+
+maintainers:
+  - Qingfang Deng <qingfang.deng@siflower.com.cn>
+
+allOf:
+  - $ref: spi-controller.yaml#
+
+properties:
+  compatible:
+    const: siflower,qspi
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 0
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - '#address-cells'
+  - '#size-cells'
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    spi@c200000 {
+      compatible = "siflower,qspi";
+      reg = <0 0xc200000 0 0x1000>;
+      clocks = <&apb_clk>;
+      interrupts = <39>;
+      pinctrl-names = "default";
+      pinctrl-0 = <&spi0_pins>;
+      #address-cells = <1>;
+      #size-cells = <0>;
+    };
-- 
2.34.1

[RFC PATCH 2/2] spi: add Siflower Quad SPI controller

[Qingfang Deng]

From: Qingfang Deng <qingfang.deng@siflower.com.cn>

Add Quad SPI controller driver for Siflower SoCs. It is based on ARM
PL022, with custom modifications to support Dual/Quad SPI modes.

Signed-off-by: Qingfang Deng <qingfang.deng@siflower.com.cn>
---
 drivers/spi/Kconfig             |   6 +
 drivers/spi/Makefile            |   1 +
 drivers/spi/spi-siflower-qspi.c | 414 ++++++++++++++++++++++++++++++++
 3 files changed, 421 insertions(+)
 create mode 100644 drivers/spi/spi-siflower-qspi.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index bc7021da2fe9..5e3a6b431a12 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -952,6 +952,12 @@ config SPI_SIFIVE
 	help
 	  This exposes the SPI controller IP from SiFive.
 
+config SPI_SIFLOWER_QSPI
+	tristate "Siflower Quad SPI Controller"
+	depends on OF && SPI_MEM
+	help
+	  Quad SPI driver for Siflower SoCs.
+
 config SPI_SLAVE_MT27XX
 	tristate "MediaTek SPI slave device"
 	depends on ARCH_MEDIATEK || COMPILE_TEST
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 4ff8d725ba5e..226aebe80a3d 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -126,6 +126,7 @@ obj-$(CONFIG_SPI_SH_HSPI)		+= spi-sh-hspi.o
 obj-$(CONFIG_SPI_SH_MSIOF)		+= spi-sh-msiof.o
 obj-$(CONFIG_SPI_SH_SCI)		+= spi-sh-sci.o
 obj-$(CONFIG_SPI_SIFIVE)		+= spi-sifive.o
+obj-$(CONFIG_SPI_SIFLOWER_QSPI)		+= spi-siflower-qspi.o
 obj-$(CONFIG_SPI_SLAVE_MT27XX)          += spi-slave-mt27xx.o
 obj-$(CONFIG_SPI_SN_F_OSPI)		+= spi-sn-f-ospi.o
 obj-$(CONFIG_SPI_SPRD)			+= spi-sprd.o
diff --git a/drivers/spi/spi-siflower-qspi.c b/drivers/spi/spi-siflower-qspi.c
new file mode 100644
index 000000000000..fd814de4bc4e
--- /dev/null
+++ b/drivers/spi/spi-siflower-qspi.c
@@ -0,0 +1,414 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/sh_clk.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/sizes.h>
+
+#include <linux/spi/spi-mem.h>
+#include <linux/spi/spi.h>
+
+/*
+ * siflower SSP fifo level
+ * */
+#define SF_SSP_FIFO_LEVEL		0x100
+/*
+ * siflower SSP register
+ * */
+#define SSP_CR0				0x000
+#define SSP_CR1				0x004
+#define SSP_DR				0x008
+#define SSP_SR				0x00C
+#define SSP_CPSR			0x010
+#define SSP_IMSC			0x014
+#define SSP_RIS				0x018
+#define SSP_MIS				0x01C
+#define SSP_ICR				0x020
+#define SSP_DMACR			0x024
+#define SSP_FIFO_LEVEL		0x028
+#define SSP_EXSPI_CMD0		0x02C
+#define SSP_EXSPI_CMD1		0x030
+#define SSP_EXSPI_CMD2		0x034
+/* SSP Control Register 0  - SSP_CR0 */
+#define SSP_CR0_EXSPI_FRAME (0x3 << 4)
+#define SSP_CR0_SPO			(0x1 << 6)
+#define SSP_CR0_SPH			(0x1 << 7)
+#define SSP_CR0_BIT_MODE(x) ((x)-1)
+#define SSP_SCR_MIN			(0x00)
+#define SSP_SCR_MAX			(0xFF)
+#define SSP_SCR_SHFT		8
+#define DFLT_CLKRATE		2
+/* SSP Control Register 1  - SSP_CR1 */
+#define SSP_CR1_MASK_SSE	(0x1 << 1)
+#define SSP_CPSR_MIN		(0x02)
+#define SSP_CPSR_MAX		(0xFE)
+#define DFLT_PRESCALE		(0x40)
+/* SSP Status Register - SSP_SR */
+#define SSP_SR_MASK_TFE		(0x1 << 0) /* Transmit FIFO empty */
+#define SSP_SR_MASK_TNF		(0x1 << 1) /* Transmit FIFO not full */
+#define SSP_SR_MASK_RNE		(0x1 << 2) /* Receive FIFO not empty */
+#define SSP_SR_MASK_RFF		(0x1 << 3) /* Receive FIFO full */
+#define SSP_SR_MASK_BSY		(0x1 << 4) /* Busy Flag */
+
+/* SSP FIFO Threshold Register - SSP_FIFO_LEVEL */
+#define SSP_FIFO_LEVEL_RX	GENMASK(14, 8) /* Receive FIFO watermark */
+#define SSP_FIFO_LEVEL_TX	GENMASK(6, 0) /* Transmit FIFO watermark */
+#define DFLT_THRESH_RX		32
+#define DFLT_THRESH_TX		32
+
+/* SSP Raw Interrupt Status Register - SSP_RIS */
+#define SSP_RIS_MASK_RORRIS	(0x1 << 0) /* Receive Overrun */
+#define SSP_RIS_MASK_RTRIS	(0x1 << 1) /* Receive Timeout */
+#define SSP_RIS_MASK_RXRIS	(0x1 << 2) /* Receive FIFO Raw Interrupt status */
+#define SSP_RIS_MASK_TXRIS	(0x1 << 3) /* Transmit FIFO Raw Interrupt status */
+
+/* EXSPI command register 0 SSP_EXSPI_CMD0 */
+#define EXSPI_CMD0_CMD_COUNT	BIT(0)		/* cmd byte, must be set at last */
+#define EXSPI_CMD0_ADDR_COUNT	GENMASK(2, 1)	/* addr bytes */
+#define EXSPI_CMD0_EHC_COUNT	BIT(3)		/* Set 1 for 4-byte address mode */
+#define EXSPI_CMD0_TX_COUNT	GENMASK(14, 4)	/* TX data bytes */
+#define EXSPI_CMD0_VALID	BIT(15)		/* Set 1 to make the cmd to be run */
+
+/* EXSPI command register 1 SSP_EXSPI_CMD1 */
+#define EXSPI_CMD1_DUMMY_COUNT	GENMASK(3, 0)	/* dummy bytes */
+#define EXSPI_CMD1_RX_COUNT	GENMASK(14, 4)	/* RX data bytes */
+
+/* EXSPI command register 2 SSP_EXSPI_CMD2 */
+/* Set 1 for 1-wire, 2 for 2-wire, 3 for 4-wire */
+#define EXSPI_CMD2_CMD_IO_MODE	GENMASK(1, 0)	/* cmd IO mode */
+#define EXSPI_CMD2_ADDR_IO_MODE	GENMASK(3, 2)	/* addr IO mode */
+#define EXSPI_CMD2_DATA_IO_MODE	GENMASK(5, 4)	/* data IO mode */
+
+#define SF_READ_TIMEOUT		(10 * HZ)
+#define MAX_S_BUF			100
+
+struct sf_qspi {
+	void __iomem *base;
+	struct clk *clk;
+	struct device *dev;
+	u32 freq;
+	int mode_bit;
+};
+
+static void sf_qspi_flush_rxfifo(struct sf_qspi *s) {
+	while (readw(s->base + SSP_SR) & SSP_SR_MASK_RNE)
+		readw(s->base + SSP_DR);
+}
+
+static int sf_qspi_wait_not_busy(struct sf_qspi *s) {
+	unsigned long timeout = jiffies + SF_READ_TIMEOUT;
+
+	do {
+		if (!(readw(s->base + SSP_SR) & SSP_SR_MASK_BSY))
+			return 0;
+
+		cond_resched();
+	} while (time_after(timeout, jiffies));
+
+	dev_err(s->dev, "I/O timed out\n");
+	return -ETIMEDOUT;
+}
+
+static int sf_qspi_wait_rx_not_empty(struct sf_qspi *s) {
+	unsigned long timeout = jiffies + SF_READ_TIMEOUT;
+
+	do {
+		if (readw(s->base + SSP_SR) & SSP_SR_MASK_RNE)
+			return 0;
+
+		cond_resched();
+	} while (time_after(timeout, jiffies));
+
+	dev_err(s->dev, "read timed out\n");
+	return -ETIMEDOUT;
+}
+
+static int sf_qspi_wait_rxfifo(struct sf_qspi *s) {
+	unsigned long timeout = jiffies + SF_READ_TIMEOUT;
+
+	do {
+		if (readw(s->base + SSP_RIS) & SSP_RIS_MASK_RXRIS)
+			return 0;
+
+		cond_resched();
+	} while (time_after(timeout, jiffies));
+
+	dev_err(s->dev, "read timed out\n");
+	return -ETIMEDOUT;
+}
+
+static void sf_qspi_enable(struct sf_qspi *s) {
+	/* Enable the SPI hardware */
+	writew(SSP_CR1_MASK_SSE, s->base + SSP_CR1);
+}
+
+static void sf_qspi_disable(struct sf_qspi *s) {
+	/* Disable the SPI hardware */
+	writew(0, s->base + SSP_CR1);
+}
+
+static void sf_qspi_xmit(struct sf_qspi *s, unsigned int nbytes, const u8 *out)
+{
+	while (nbytes--)
+		writew(*out++, s->base + SSP_DR);
+}
+
+static int sf_qspi_rcv(struct sf_qspi *s, unsigned int nbytes, u8 *in)
+{
+	int ret, i;
+
+	while (nbytes >= DFLT_THRESH_RX) {
+		/* wait for RX FIFO to reach the threshold */
+		ret = sf_qspi_wait_rxfifo(s);
+		if (ret)
+			return ret;
+
+		for (i = 0; i < DFLT_THRESH_RX; i++)
+			*in++ = readw(s->base + SSP_DR);
+
+		nbytes -= DFLT_THRESH_RX;
+	}
+
+	/* read the remaining data */
+	while (nbytes) {
+		ret = sf_qspi_wait_rx_not_empty(s);
+		if (ret)
+			return ret;
+
+		*in++ = readw(s->base + SSP_DR);
+		nbytes--;
+	}
+
+	return 0;
+}
+
+static inline u32 spi_rate(u32 rate, u16 csdvsr, u16 scr) {
+	return rate / (csdvsr * (1 + scr));
+}
+
+static void sf_qspi_set_param(struct sf_qspi *s, const struct spi_mem_op *op) {
+	unsigned int tx_count = 0, rx_count = 0;
+	u8 cmd_io, addr_io, data_io;
+	u8 cmd_count, addr_count, ehc_count;
+
+	cmd_io = op->cmd.buswidth == 4 ? 3 : op->cmd.buswidth;
+	addr_io = op->addr.buswidth == 4 ? 3 : op->addr.buswidth;
+	data_io = op->data.buswidth == 4 ? 3 : op->data.buswidth;
+
+	if (op->data.nbytes) {
+		if (op->data.dir == SPI_MEM_DATA_IN) {
+			rx_count = op->data.nbytes;
+		} else {
+			tx_count = op->data.nbytes;
+		}
+	}
+	if (op->addr.nbytes > 3) {
+		addr_count = 3;
+		ehc_count = 1;
+	} else {
+		addr_count = op->addr.nbytes;
+		ehc_count = 0;
+	}
+	cmd_count = op->cmd.nbytes;
+
+	writew(FIELD_PREP(EXSPI_CMD2_CMD_IO_MODE, cmd_io) |
+	       FIELD_PREP(EXSPI_CMD2_ADDR_IO_MODE, addr_io) |
+	       FIELD_PREP(EXSPI_CMD2_DATA_IO_MODE, data_io),
+	       s->base + SSP_EXSPI_CMD2);
+	writew(FIELD_PREP(EXSPI_CMD1_DUMMY_COUNT, op->dummy.nbytes) |
+	       FIELD_PREP(EXSPI_CMD1_RX_COUNT, rx_count),
+	       s->base + SSP_EXSPI_CMD1);
+	writew(EXSPI_CMD0_VALID |
+	       FIELD_PREP(EXSPI_CMD0_CMD_COUNT, op->cmd.nbytes) |
+	       FIELD_PREP(EXSPI_CMD0_ADDR_COUNT, addr_count) |
+	       FIELD_PREP(EXSPI_CMD0_EHC_COUNT, ehc_count) |
+	       FIELD_PREP(EXSPI_CMD0_TX_COUNT, tx_count),
+	       s->base + SSP_EXSPI_CMD0);
+}
+
+static int sf_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
+{
+	struct sf_qspi *s = spi_controller_get_devdata(mem->spi->master);
+	unsigned int pops = 0;
+	int ret, i, op_len;
+	const u8 *tx_buf = NULL;
+	u8 *rx_buf = NULL, op_buf[MAX_S_BUF];
+
+	if (op->data.nbytes) {
+		if (op->data.dir == SPI_MEM_DATA_IN) {
+			rx_buf = op->data.buf.in;
+		} else {
+			tx_buf = op->data.buf.out;
+		}
+	}
+	op_len = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes;
+	sf_qspi_set_param(s, op);
+	/*
+	 * Avoid using malloc() here so that we can use this code in SPL where
+	 * simple malloc may be used. That implementation does not allow free()
+	 * so repeated calls to this code can exhaust the space.
+	 *
+	 * The value of op_len is small, since it does not include the actual
+	 * data being sent, only the op-code and address. In fact, it should be
+	 * popssible to just use a small fixed value here instead of op_len.
+	 */
+	op_buf[pops++] = op->cmd.opcode;
+	if (op->addr.nbytes) {
+		for (i = 0; i < op->addr.nbytes; i++)
+			op_buf[pops + i] = op->addr.val >>
+							  (8 * (op->addr.nbytes - i - 1));
+		pops += op->addr.nbytes;
+	}
+
+	sf_qspi_flush_rxfifo(s);
+	memset(op_buf + pops, 0xff, op->dummy.nbytes);
+	sf_qspi_xmit(s, op_len, op_buf);
+	if (tx_buf) {
+		sf_qspi_xmit(s, op->data.nbytes, tx_buf);
+	}
+	sf_qspi_enable(s);
+	if (rx_buf) {
+		ret = sf_qspi_rcv(s, op->data.nbytes, rx_buf);
+	} else {
+		ret = sf_qspi_wait_not_busy(s);
+	}
+	sf_qspi_disable(s);
+	return ret;
+}
+
+static int sf_qspi_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
+{
+	u32 nbytes;
+
+	nbytes = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes;
+	if (nbytes >= SF_SSP_FIFO_LEVEL)
+		return -ENOTSUPP;
+
+	if (op->data.dir == SPI_MEM_DATA_IN)
+		op->data.nbytes = min_t(unsigned int, op->data.nbytes,
+					SF_SSP_FIFO_LEVEL);
+	else
+		op->data.nbytes = min_t(unsigned int, op->data.nbytes,
+					SF_SSP_FIFO_LEVEL - nbytes);
+
+	return 0;
+}
+
+static int sf_qspi_default_setup(struct sf_qspi *s) {
+	u16 scr = SSP_SCR_MIN, cr0 = 0, cpsr = SSP_CPSR_MIN, best_scr = scr, best_cpsr = cpsr;
+	u32 min, max, best_freq = 0, tmp;
+	u32 rate = clk_get_rate(s->clk), speed = s->freq;
+	bool found = false;
+
+	writew(DFLT_PRESCALE, s->base + SSP_CPSR);
+
+	max = spi_rate(rate, SSP_CPSR_MIN, SSP_SCR_MIN);
+	min = spi_rate(rate, SSP_CPSR_MAX, SSP_SCR_MAX);
+
+	if (speed > max || speed < min) {
+		dev_err(s->dev, "Tried to set speed to %dHz but min=%d and max=%d\n", speed, min, max);
+		return -EINVAL;
+	}
+	while (cpsr <= SSP_CPSR_MAX && !found) {
+		while (scr <= SSP_SCR_MAX) {
+			tmp = spi_rate(rate, cpsr, scr);
+			if (abs(speed - tmp) < abs(speed - best_freq)) {
+				best_freq = tmp;
+				best_cpsr = cpsr;
+				best_scr = scr;
+				if (tmp == speed) {
+					found = true;
+					break;
+				}
+			}
+			scr++;
+		}
+		cpsr += 2;
+		scr = SSP_SCR_MIN;
+	}
+	writew(best_cpsr, s->base + SSP_CPSR);
+	cr0 = SSP_CR0_BIT_MODE(8);
+	cr0 |= best_scr << 8;
+	/*set module*/
+	cr0 &= ~(SSP_CR0_SPH | SSP_CR0_SPO);
+	if(s->mode_bit & SPI_CPHA)
+		cr0 |= SSP_CR0_SPH;
+	if(s->mode_bit & SPI_CPOL)
+		cr0 |= SSP_CR0_SPO;
+	cr0 |= SSP_CR0_EXSPI_FRAME;
+	writew(cr0, s->base + SSP_CR0);
+	/*clear and enable interrupt*/
+	writew(FIELD_PREP(SSP_FIFO_LEVEL_RX, DFLT_THRESH_RX) |
+	       FIELD_PREP(SSP_FIFO_LEVEL_TX, DFLT_THRESH_TX),
+	       s->base + SSP_FIFO_LEVEL);
+
+	return 0;
+}
+
+static const struct spi_controller_mem_ops sf_qspi_mem_ops = {
+	.adjust_op_size = sf_qspi_adjust_op_size,
+	.exec_op = sf_qspi_exec_op,
+};
+
+static int sf_qspi_probe(struct platform_device *pdev) {
+	struct spi_controller *master;
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node, *nc;
+	struct sf_qspi *s;
+
+	master = devm_spi_alloc_host(&pdev->dev, sizeof(*s));
+	if (!master)
+		return -ENOMEM;
+	master->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_DUAL |
+			    SPI_TX_QUAD;
+	s = spi_controller_get_devdata(master);
+	s->dev = dev;
+	s->mode_bit = 0;
+	platform_set_drvdata(pdev, s);
+	s->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(s->base))
+		return PTR_ERR(s->base);
+
+	s->clk = devm_clk_get_enabled(dev, NULL);
+	if (IS_ERR(s->clk))
+		return PTR_ERR(s->clk);
+
+	for_each_available_child_of_node(dev->of_node, nc) {
+		of_property_read_u32(nc, "spi-max-frequency", &s->freq);
+	}
+
+	master->bus_num = pdev->id;
+	master->num_chipselect = 1;
+
+	master->mem_ops = &sf_qspi_mem_ops;
+	sf_qspi_default_setup(s);
+	master->dev.of_node = np;
+	return devm_spi_register_controller(dev, master);
+}
+
+static const struct of_device_id sf_qspi_ids[] = {
+	{ .compatible = "siflower,qspi" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, sf_qspi_ids);
+
+static struct platform_driver sf_qspi_driver = {
+	.driver = {
+		.name = "siflower_qspi",
+		.of_match_table = sf_qspi_ids,
+	},
+	.probe		= sf_qspi_probe,
+};
+module_platform_driver(sf_qspi_driver);
+
+MODULE_LICENSE("GPL");
-- 
2.34.1

Re: [RFC PATCH 1/2] spi: dt-bindings: add Siflower Quad SPI controller

[Rob Herring]

On Fri, 29 Mar 2024 09:51:46 +0800, Qingfang Deng wrote:
> From: Qingfang Deng <qingfang.deng@siflower.com.cn>
> 
> Add YAML devicetree bindings for Siflower Quad SPI controller.
> 
> Signed-off-by: Qingfang Deng <qingfang.deng@siflower.com.cn>
> ---
>  .../bindings/spi/siflower,qspi.yaml           | 54 +++++++++++++++++++
>  1 file changed, 54 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/spi/siflower,qspi.yaml
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/spi/siflower,qspi.example.dtb: spi@c200000: reg: [[0, 203423744], [0, 4096]] is too long
	from schema $id: http://devicetree.org/schemas/spi/siflower,qspi.yaml#
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/spi/siflower,qspi.example.dtb: spi@c200000: Unevaluated properties are not allowed ('reg' was unexpected)
	from schema $id: http://devicetree.org/schemas/spi/siflower,qspi.yaml#

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20240329015147.1481349-1-dqfext@gmail.com

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.

[RFC PATCH v2 1/2] spi: dt-bindings: add Siflower Quad SPI controller

[Qingfang Deng]

From: Qingfang Deng <qingfang.deng@siflower.com.cn>

Add YAML devicetree bindings for Siflower Quad SPI controller.

Signed-off-by: Qingfang Deng <qingfang.deng@siflower.com.cn>
---
v2: fix dt_binding_check reported errors

 .../bindings/spi/siflower,qspi.yaml           | 54 +++++++++++++++++++
 1 file changed, 54 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/spi/siflower,qspi.yaml

diff --git a/Documentation/devicetree/bindings/spi/siflower,qspi.yaml b/Documentation/devicetree/bindings/spi/siflower,qspi.yaml
new file mode 100644
index 000000000000..15ce25a2176a
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/siflower,qspi.yaml
@@ -0,0 +1,54 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/spi/siflower,qspi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Siflower Quad Serial Peripheral Interface (QSPI)
+
+maintainers:
+  - Qingfang Deng <qingfang.deng@siflower.com.cn>
+
+allOf:
+  - $ref: spi-controller.yaml#
+
+properties:
+  compatible:
+    const: siflower,qspi
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 0
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - '#address-cells'
+  - '#size-cells'
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    spi@c200000 {
+      compatible = "siflower,qspi";
+      reg = <0xc200000 0x1000>;
+      clocks = <&apb_clk>;
+      interrupts = <39>;
+      pinctrl-names = "default";
+      pinctrl-0 = <&spi0_pins>;
+      #address-cells = <1>;
+      #size-cells = <0>;
+    };
-- 
2.34.1

[RFC PATCH v2 2/2] spi: add Siflower Quad SPI controller

[Qingfang Deng]

From: Qingfang Deng <qingfang.deng@siflower.com.cn>

Add Quad SPI controller driver for Siflower SoCs. It is based on ARM
PL022, with custom modifications to support Dual/Quad SPI modes.

Signed-off-by: Qingfang Deng <qingfang.deng@siflower.com.cn>
---
v2: fix some style problems reported by checkpatch.pl

 drivers/spi/Kconfig             |   6 +
 drivers/spi/Makefile            |   1 +
 drivers/spi/spi-siflower-qspi.c | 423 ++++++++++++++++++++++++++++++++
 3 files changed, 430 insertions(+)
 create mode 100644 drivers/spi/spi-siflower-qspi.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index bc7021da2fe9..5e3a6b431a12 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -952,6 +952,12 @@ config SPI_SIFIVE
 	help
 	  This exposes the SPI controller IP from SiFive.
 
+config SPI_SIFLOWER_QSPI
+	tristate "Siflower Quad SPI Controller"
+	depends on OF && SPI_MEM
+	help
+	  Quad SPI driver for Siflower SoCs.
+
 config SPI_SLAVE_MT27XX
 	tristate "MediaTek SPI slave device"
 	depends on ARCH_MEDIATEK || COMPILE_TEST
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 4ff8d725ba5e..226aebe80a3d 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -126,6 +126,7 @@ obj-$(CONFIG_SPI_SH_HSPI)		+= spi-sh-hspi.o
 obj-$(CONFIG_SPI_SH_MSIOF)		+= spi-sh-msiof.o
 obj-$(CONFIG_SPI_SH_SCI)		+= spi-sh-sci.o
 obj-$(CONFIG_SPI_SIFIVE)		+= spi-sifive.o
+obj-$(CONFIG_SPI_SIFLOWER_QSPI)		+= spi-siflower-qspi.o
 obj-$(CONFIG_SPI_SLAVE_MT27XX)          += spi-slave-mt27xx.o
 obj-$(CONFIG_SPI_SN_F_OSPI)		+= spi-sn-f-ospi.o
 obj-$(CONFIG_SPI_SPRD)			+= spi-sprd.o
diff --git a/drivers/spi/spi-siflower-qspi.c b/drivers/spi/spi-siflower-qspi.c
new file mode 100644
index 000000000000..c5dfa0d31681
--- /dev/null
+++ b/drivers/spi/spi-siflower-qspi.c
@@ -0,0 +1,423 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/sh_clk.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/sizes.h>
+
+#include <linux/spi/spi-mem.h>
+#include <linux/spi/spi.h>
+
+/*
+ * siflower SSP fifo level
+ */
+#define SF_SSP_FIFO_LEVEL		0x100
+/*
+ * siflower SSP register
+ */
+#define SSP_CR0				0x000
+#define SSP_CR1				0x004
+#define SSP_DR				0x008
+#define SSP_SR				0x00C
+#define SSP_CPSR			0x010
+#define SSP_IMSC			0x014
+#define SSP_RIS				0x018
+#define SSP_MIS				0x01C
+#define SSP_ICR				0x020
+#define SSP_DMACR			0x024
+#define SSP_FIFO_LEVEL		0x028
+#define SSP_EXSPI_CMD0		0x02C
+#define SSP_EXSPI_CMD1		0x030
+#define SSP_EXSPI_CMD2		0x034
+/* SSP Control Register 0  - SSP_CR0 */
+#define SSP_CR0_EXSPI_FRAME (0x3 << 4)
+#define SSP_CR0_SPO			(0x1 << 6)
+#define SSP_CR0_SPH			(0x1 << 7)
+#define SSP_CR0_BIT_MODE(x) ((x)-1)
+#define SSP_SCR_MIN			(0x00)
+#define SSP_SCR_MAX			(0xFF)
+#define SSP_SCR_SHFT		8
+#define DFLT_CLKRATE		2
+/* SSP Control Register 1  - SSP_CR1 */
+#define SSP_CR1_MASK_SSE	(0x1 << 1)
+#define SSP_CPSR_MIN		(0x02)
+#define SSP_CPSR_MAX		(0xFE)
+#define DFLT_PRESCALE		(0x40)
+/* SSP Status Register - SSP_SR */
+#define SSP_SR_MASK_TFE		(0x1 << 0) /* Transmit FIFO empty */
+#define SSP_SR_MASK_TNF		(0x1 << 1) /* Transmit FIFO not full */
+#define SSP_SR_MASK_RNE		(0x1 << 2) /* Receive FIFO not empty */
+#define SSP_SR_MASK_RFF		(0x1 << 3) /* Receive FIFO full */
+#define SSP_SR_MASK_BSY		(0x1 << 4) /* Busy Flag */
+
+/* SSP FIFO Threshold Register - SSP_FIFO_LEVEL */
+#define SSP_FIFO_LEVEL_RX	GENMASK(14, 8) /* Receive FIFO watermark */
+#define SSP_FIFO_LEVEL_TX	GENMASK(6, 0) /* Transmit FIFO watermark */
+#define DFLT_THRESH_RX		32
+#define DFLT_THRESH_TX		32
+
+/* SSP Raw Interrupt Status Register - SSP_RIS */
+#define SSP_RIS_MASK_RORRIS	(0x1 << 0) /* Receive Overrun */
+#define SSP_RIS_MASK_RTRIS	(0x1 << 1) /* Receive Timeout */
+#define SSP_RIS_MASK_RXRIS	(0x1 << 2) /* Receive FIFO Raw Interrupt status */
+#define SSP_RIS_MASK_TXRIS	(0x1 << 3) /* Transmit FIFO Raw Interrupt status */
+
+/* EXSPI command register 0 SSP_EXSPI_CMD0 */
+#define EXSPI_CMD0_CMD_COUNT	BIT(0)		/* cmd byte, must be set at last */
+#define EXSPI_CMD0_ADDR_COUNT	GENMASK(2, 1)	/* addr bytes */
+#define EXSPI_CMD0_EHC_COUNT	BIT(3)		/* Set 1 for 4-byte address mode */
+#define EXSPI_CMD0_TX_COUNT	GENMASK(14, 4)	/* TX data bytes */
+#define EXSPI_CMD0_VALID	BIT(15)		/* Set 1 to make the cmd to be run */
+
+/* EXSPI command register 1 SSP_EXSPI_CMD1 */
+#define EXSPI_CMD1_DUMMY_COUNT	GENMASK(3, 0)	/* dummy bytes */
+#define EXSPI_CMD1_RX_COUNT	GENMASK(14, 4)	/* RX data bytes */
+
+/* EXSPI command register 2 SSP_EXSPI_CMD2 */
+/* Set 1 for 1-wire, 2 for 2-wire, 3 for 4-wire */
+#define EXSPI_CMD2_CMD_IO_MODE	GENMASK(1, 0)	/* cmd IO mode */
+#define EXSPI_CMD2_ADDR_IO_MODE	GENMASK(3, 2)	/* addr IO mode */
+#define EXSPI_CMD2_DATA_IO_MODE	GENMASK(5, 4)	/* data IO mode */
+
+#define SF_READ_TIMEOUT		(10 * HZ)
+#define MAX_S_BUF			100
+
+struct sf_qspi {
+	void __iomem *base;
+	struct clk *clk;
+	struct device *dev;
+	u32 freq;
+	int mode_bit;
+};
+
+static void sf_qspi_flush_rxfifo(struct sf_qspi *s)
+{
+	while (readw(s->base + SSP_SR) & SSP_SR_MASK_RNE)
+		readw(s->base + SSP_DR);
+}
+
+static int sf_qspi_wait_not_busy(struct sf_qspi *s)
+{
+	unsigned long timeout = jiffies + SF_READ_TIMEOUT;
+
+	do {
+		if (!(readw(s->base + SSP_SR) & SSP_SR_MASK_BSY))
+			return 0;
+
+		cond_resched();
+	} while (time_after(timeout, jiffies));
+
+	dev_err(s->dev, "I/O timed out\n");
+	return -ETIMEDOUT;
+}
+
+static int sf_qspi_wait_rx_not_empty(struct sf_qspi *s)
+{
+	unsigned long timeout = jiffies + SF_READ_TIMEOUT;
+
+	do {
+		if (readw(s->base + SSP_SR) & SSP_SR_MASK_RNE)
+			return 0;
+
+		cond_resched();
+	} while (time_after(timeout, jiffies));
+
+	dev_err(s->dev, "read timed out\n");
+	return -ETIMEDOUT;
+}
+
+static int sf_qspi_wait_rxfifo(struct sf_qspi *s)
+{
+	unsigned long timeout = jiffies + SF_READ_TIMEOUT;
+
+	do {
+		if (readw(s->base + SSP_RIS) & SSP_RIS_MASK_RXRIS)
+			return 0;
+
+		cond_resched();
+	} while (time_after(timeout, jiffies));
+
+	dev_err(s->dev, "read timed out\n");
+	return -ETIMEDOUT;
+}
+
+static void sf_qspi_enable(struct sf_qspi *s)
+{
+	/* Enable the SPI hardware */
+	writew(SSP_CR1_MASK_SSE, s->base + SSP_CR1);
+}
+
+static void sf_qspi_disable(struct sf_qspi *s)
+{
+	/* Disable the SPI hardware */
+	writew(0, s->base + SSP_CR1);
+}
+
+static void sf_qspi_xmit(struct sf_qspi *s, unsigned int nbytes, const u8 *out)
+{
+	while (nbytes--)
+		writew(*out++, s->base + SSP_DR);
+}
+
+static int sf_qspi_rcv(struct sf_qspi *s, unsigned int nbytes, u8 *in)
+{
+	int ret, i;
+
+	while (nbytes >= DFLT_THRESH_RX) {
+		/* wait for RX FIFO to reach the threshold */
+		ret = sf_qspi_wait_rxfifo(s);
+		if (ret)
+			return ret;
+
+		for (i = 0; i < DFLT_THRESH_RX; i++)
+			*in++ = readw(s->base + SSP_DR);
+
+		nbytes -= DFLT_THRESH_RX;
+	}
+
+	/* read the remaining data */
+	while (nbytes) {
+		ret = sf_qspi_wait_rx_not_empty(s);
+		if (ret)
+			return ret;
+
+		*in++ = readw(s->base + SSP_DR);
+		nbytes--;
+	}
+
+	return 0;
+}
+
+static inline u32 spi_rate(u32 rate, u16 csdvsr, u16 scr)
+{
+	return rate / (csdvsr * (1 + scr));
+}
+
+static void sf_qspi_set_param(struct sf_qspi *s, const struct spi_mem_op *op)
+{
+	unsigned int tx_count = 0, rx_count = 0;
+	u8 cmd_io, addr_io, data_io;
+	u8 cmd_count, addr_count, ehc_count;
+
+	cmd_io = op->cmd.buswidth == 4 ? 3 : op->cmd.buswidth;
+	addr_io = op->addr.buswidth == 4 ? 3 : op->addr.buswidth;
+	data_io = op->data.buswidth == 4 ? 3 : op->data.buswidth;
+
+	if (op->data.nbytes) {
+		if (op->data.dir == SPI_MEM_DATA_IN)
+			rx_count = op->data.nbytes;
+		else
+			tx_count = op->data.nbytes;
+	}
+	if (op->addr.nbytes > 3) {
+		addr_count = 3;
+		ehc_count = 1;
+	} else {
+		addr_count = op->addr.nbytes;
+		ehc_count = 0;
+	}
+	cmd_count = op->cmd.nbytes;
+
+	writew(FIELD_PREP(EXSPI_CMD2_CMD_IO_MODE, cmd_io) |
+	       FIELD_PREP(EXSPI_CMD2_ADDR_IO_MODE, addr_io) |
+	       FIELD_PREP(EXSPI_CMD2_DATA_IO_MODE, data_io),
+	       s->base + SSP_EXSPI_CMD2);
+	writew(FIELD_PREP(EXSPI_CMD1_DUMMY_COUNT, op->dummy.nbytes) |
+	       FIELD_PREP(EXSPI_CMD1_RX_COUNT, rx_count),
+	       s->base + SSP_EXSPI_CMD1);
+	writew(EXSPI_CMD0_VALID |
+	       FIELD_PREP(EXSPI_CMD0_CMD_COUNT, op->cmd.nbytes) |
+	       FIELD_PREP(EXSPI_CMD0_ADDR_COUNT, addr_count) |
+	       FIELD_PREP(EXSPI_CMD0_EHC_COUNT, ehc_count) |
+	       FIELD_PREP(EXSPI_CMD0_TX_COUNT, tx_count),
+	       s->base + SSP_EXSPI_CMD0);
+}
+
+static int sf_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
+{
+	struct sf_qspi *s = spi_controller_get_devdata(mem->spi->master);
+	unsigned int pops = 0;
+	int ret, i, op_len;
+	const u8 *tx_buf = NULL;
+	u8 *rx_buf = NULL, op_buf[MAX_S_BUF];
+
+	if (op->data.nbytes) {
+		if (op->data.dir == SPI_MEM_DATA_IN)
+			rx_buf = op->data.buf.in;
+		else
+			tx_buf = op->data.buf.out;
+	}
+	op_len = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes;
+	sf_qspi_set_param(s, op);
+	/*
+	 * Avoid using malloc() here so that we can use this code in SPL where
+	 * simple malloc may be used. That implementation does not allow free()
+	 * so repeated calls to this code can exhaust the space.
+	 *
+	 * The value of op_len is small, since it does not include the actual
+	 * data being sent, only the op-code and address. In fact, it should be
+	 * popssible to just use a small fixed value here instead of op_len.
+	 */
+	op_buf[pops++] = op->cmd.opcode;
+	if (op->addr.nbytes) {
+		for (i = 0; i < op->addr.nbytes; i++)
+			op_buf[pops + i] = op->addr.val >>
+					   (8 * (op->addr.nbytes - i - 1));
+		pops += op->addr.nbytes;
+	}
+
+	sf_qspi_flush_rxfifo(s);
+	memset(op_buf + pops, 0xff, op->dummy.nbytes);
+	sf_qspi_xmit(s, op_len, op_buf);
+	if (tx_buf)
+		sf_qspi_xmit(s, op->data.nbytes, tx_buf);
+
+	sf_qspi_enable(s);
+	if (rx_buf)
+		ret = sf_qspi_rcv(s, op->data.nbytes, rx_buf);
+	else
+		ret = sf_qspi_wait_not_busy(s);
+
+	sf_qspi_disable(s);
+	return ret;
+}
+
+static int sf_qspi_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
+{
+	u32 nbytes;
+
+	nbytes = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes;
+	if (nbytes >= SF_SSP_FIFO_LEVEL)
+		return -EOPNOTSUPP;
+
+	if (op->data.dir == SPI_MEM_DATA_IN)
+		op->data.nbytes = min_t(unsigned int, op->data.nbytes,
+					SF_SSP_FIFO_LEVEL);
+	else
+		op->data.nbytes = min_t(unsigned int, op->data.nbytes,
+					SF_SSP_FIFO_LEVEL - nbytes);
+
+	return 0;
+}
+
+static int sf_qspi_default_setup(struct sf_qspi *s)
+{
+	u16 scr = SSP_SCR_MIN, cr0 = 0, cpsr = SSP_CPSR_MIN, best_scr = scr, best_cpsr = cpsr;
+	u32 min, max, best_freq = 0, tmp;
+	u32 rate = clk_get_rate(s->clk), speed = s->freq;
+	bool found = false;
+
+	writew(DFLT_PRESCALE, s->base + SSP_CPSR);
+
+	max = spi_rate(rate, SSP_CPSR_MIN, SSP_SCR_MIN);
+	min = spi_rate(rate, SSP_CPSR_MAX, SSP_SCR_MAX);
+
+	if (speed > max || speed < min) {
+		dev_err(s->dev, "Tried to set speed to %dHz but min=%d and max=%d\n",
+			speed, min, max);
+		return -EINVAL;
+	}
+	while (cpsr <= SSP_CPSR_MAX && !found) {
+		while (scr <= SSP_SCR_MAX) {
+			tmp = spi_rate(rate, cpsr, scr);
+			if (abs(speed - tmp) < abs(speed - best_freq)) {
+				best_freq = tmp;
+				best_cpsr = cpsr;
+				best_scr = scr;
+				if (tmp == speed) {
+					found = true;
+					break;
+				}
+			}
+			scr++;
+		}
+		cpsr += 2;
+		scr = SSP_SCR_MIN;
+	}
+	writew(best_cpsr, s->base + SSP_CPSR);
+	cr0 = SSP_CR0_BIT_MODE(8);
+	cr0 |= best_scr << 8;
+	/* set module */
+	cr0 &= ~(SSP_CR0_SPH | SSP_CR0_SPO);
+	if (s->mode_bit & SPI_CPHA)
+		cr0 |= SSP_CR0_SPH;
+	if (s->mode_bit & SPI_CPOL)
+		cr0 |= SSP_CR0_SPO;
+	cr0 |= SSP_CR0_EXSPI_FRAME;
+	writew(cr0, s->base + SSP_CR0);
+	/* clear and enable interrupt */
+	writew(FIELD_PREP(SSP_FIFO_LEVEL_RX, DFLT_THRESH_RX) |
+	       FIELD_PREP(SSP_FIFO_LEVEL_TX, DFLT_THRESH_TX),
+	       s->base + SSP_FIFO_LEVEL);
+
+	return 0;
+}
+
+static const struct spi_controller_mem_ops sf_qspi_mem_ops = {
+	.adjust_op_size = sf_qspi_adjust_op_size,
+	.exec_op = sf_qspi_exec_op,
+};
+
+static int sf_qspi_probe(struct platform_device *pdev)
+{
+	struct spi_controller *master;
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node, *nc;
+	struct sf_qspi *s;
+
+	master = devm_spi_alloc_host(&pdev->dev, sizeof(*s));
+	if (!master)
+		return -ENOMEM;
+	master->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_DUAL |
+			    SPI_TX_QUAD;
+	s = spi_controller_get_devdata(master);
+	s->dev = dev;
+	s->mode_bit = 0;
+	platform_set_drvdata(pdev, s);
+	s->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(s->base))
+		return PTR_ERR(s->base);
+
+	s->clk = devm_clk_get_enabled(dev, NULL);
+	if (IS_ERR(s->clk))
+		return PTR_ERR(s->clk);
+
+	for_each_available_child_of_node(dev->of_node, nc) {
+		of_property_read_u32(nc, "spi-max-frequency", &s->freq);
+	}
+
+	master->bus_num = pdev->id;
+	master->num_chipselect = 1;
+
+	master->mem_ops = &sf_qspi_mem_ops;
+	sf_qspi_default_setup(s);
+	master->dev.of_node = np;
+	return devm_spi_register_controller(dev, master);
+}
+
+static const struct of_device_id sf_qspi_ids[] = {
+	{ .compatible = "siflower,qspi" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, sf_qspi_ids);
+
+static struct platform_driver sf_qspi_driver = {
+	.driver = {
+		.name = "siflower_qspi",
+		.of_match_table = sf_qspi_ids,
+	},
+	.probe		= sf_qspi_probe,
+};
+module_platform_driver(sf_qspi_driver);
+
+MODULE_LICENSE("GPL");
-- 
2.34.1

Re: [RFC PATCH v2 1/2] spi: dt-bindings: add Siflower Quad SPI controller

[Krzysztof Kozlowski]

On 29/03/2024 06:46, Qingfang Deng wrote:
> From: Qingfang Deng <qingfang.deng@siflower.com.cn>
> 
> Add YAML devicetree bindings for Siflower Quad SPI controller.

Not much improved.

Do not attach (thread) your patchsets to some other threads (unrelated
or older versions). This buries them deep in the mailbox and might
interfere with applying entire sets.

Allow people to actually review your code - give them some time, like
24h between postings.

> 
> Signed-off-by: Qingfang Deng <qingfang.deng@siflower.com.cn>
> ---
> v2: fix dt_binding_check reported errors
> 
>  .../bindings/spi/siflower,qspi.yaml           | 54 +++++++++++++++++++
>  1 file changed, 54 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/spi/siflower,qspi.yaml
> 
> diff --git a/Documentation/devicetree/bindings/spi/siflower,qspi.yaml b/Documentation/devicetree/bindings/spi/siflower,qspi.yaml
> new file mode 100644
> index 000000000000..15ce25a2176a
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/spi/siflower,qspi.yaml
> @@ -0,0 +1,54 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/spi/siflower,qspi.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Siflower Quad Serial Peripheral Interface (QSPI)
> +
> +maintainers:
> +  - Qingfang Deng <qingfang.deng@siflower.com.cn>
> +
> +allOf:
> +  - $ref: spi-controller.yaml#
> +
> +properties:
> +  compatible:
> +    const: siflower,qspi
> +

My previous comments stay valid. Respond to them.

Best regards,
Krzysztof

Re: [RFC PATCH 1/2] spi: dt-bindings: add Siflower Quad SPI controller

[Krzysztof Kozlowski]

On 29/03/2024 02:51, Qingfang Deng wrote:
> From: Qingfang Deng <qingfang.deng@siflower.com.cn>
> 
> Add YAML devicetree bindings for Siflower Quad SPI controller.

Describe the hardware. What is this Siflower?
> 
> Signed-off-by: Qingfang Deng <qingfang.deng@siflower.com.cn>
> ---
>  .../bindings/spi/siflower,qspi.yaml           | 54 +++++++++++++++++++
>  1 file changed, 54 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/spi/siflower,qspi.yaml
> 
> diff --git a/Documentation/devicetree/bindings/spi/siflower,qspi.yaml b/Documentation/devicetree/bindings/spi/siflower,qspi.yaml
> new file mode 100644
> index 000000000000..c2dbe82affc2
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/spi/siflower,qspi.yaml
> @@ -0,0 +1,54 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/spi/siflower,qspi.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Siflower Quad Serial Peripheral Interface (QSPI)
> +
> +maintainers:
> +  - Qingfang Deng <qingfang.deng@siflower.com.cn>
> +
> +allOf:
> +  - $ref: spi-controller.yaml#
> +
> +properties:
> +  compatible:
> +    const: siflower,qspi

Except that this was not tested, aren't you adding it for some SoC? If
so, then you miss here SoC part.

Best regards,
Krzysztof

Re: [RFC PATCH 1/2] spi: dt-bindings: add Siflower Quad SPI controller

[Qingfang Deng]

Hi Krzysztof,

On Sun, Mar 31, 2024 at 1:42 AM Krzysztof Kozlowski
<krzysztof.kozlowski@linaro.org> wrote:
> On 29/03/2024 02:51, Qingfang Deng wrote:
> > Add YAML devicetree bindings for Siflower Quad SPI controller.
>
> Describe the hardware. What is this Siflower?

It's a new RISC-V SoC which hasn't been upstreamed yet.

> > +properties:
> > +  compatible:
> > +    const: siflower,qspi
>
> Except that this was not tested, aren't you adding it for some SoC? If
> so, then you miss here SoC part.

I should add the "siflower" prefix to
Documentation/devicetree/bindings/vendor-prefixes.yaml, right?

Regards,
Qingfang

Re: [RFC PATCH 1/2] spi: dt-bindings: add Siflower Quad SPI controller

[Krzysztof Kozlowski]

On 01/04/2024 05:36, Qingfang Deng wrote:
> Hi Krzysztof,
> 
> On Sun, Mar 31, 2024 at 1:42 AM Krzysztof Kozlowski
> <krzysztof.kozlowski@linaro.org> wrote:
>> On 29/03/2024 02:51, Qingfang Deng wrote:
>>> Add YAML devicetree bindings for Siflower Quad SPI controller.
>>
>> Describe the hardware. What is this Siflower?
> 
> It's a new RISC-V SoC which hasn't been upstreamed yet.
> 
>>> +properties:
>>> +  compatible:
>>> +    const: siflower,qspi
>>
>> Except that this was not tested, aren't you adding it for some SoC? If
>> so, then you miss here SoC part.
> 
> I should add the "siflower" prefix to
> Documentation/devicetree/bindings/vendor-prefixes.yaml, right?

Isn't it already there? Then obvious you must, but that was not the
point. Please read writing-bindings document. Compatibles should be SoC
specific, not generic. "qspi" is generic.

Best regards,
Krzysztof

Re: [RFC PATCH 1/2] spi: dt-bindings: add Siflower Quad SPI controller

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 441 bytes --]

On Sat, Mar 30, 2024 at 06:42:11PM +0100, Krzysztof Kozlowski wrote:
> On 29/03/2024 02:51, Qingfang Deng wrote:

> > Add YAML devicetree bindings for Siflower Quad SPI controller.

> Describe the hardware. What is this Siflower?

That seems like a perfectly adequate description - ${VENDOR} ${FUNCTION}
is normal enough and Quad SPI is a well known standard.  We don't need a
marketing spiel for whatever IP version is currently supported.

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

Re: [RFC PATCH 1/2] spi: dt-bindings: add Siflower Quad SPI controller

[Krzysztof Kozlowski]

On 02/04/2024 14:22, Mark Brown wrote:
> On Sat, Mar 30, 2024 at 06:42:11PM +0100, Krzysztof Kozlowski wrote:
>> On 29/03/2024 02:51, Qingfang Deng wrote:
> 
>>> Add YAML devicetree bindings for Siflower Quad SPI controller.
> 
>> Describe the hardware. What is this Siflower?
> 
> That seems like a perfectly adequate description - ${VENDOR} ${FUNCTION}
> is normal enough and Quad SPI is a well known standard.  We don't need a
> marketing spiel for whatever IP version is currently supported.

What we are missing here is the final product, so for example the SoC.
Is the company making exactly one and only one Quad SPI? I provided more
explanation what is missing further in the quoted email and in follow up
email/discussion.

Best regards,
Krzysztof