Re: [PATCH 3/3] SPI: Ingenic: Add SFC support for Ingenic SoCs.

[Paul Cercueil <paul@crapouillou.net>]

Hi Zhou,


Le sam., juil. 23 2022 at 00:48:30 +0800, 周琰杰 (Zhou Yanjie) 
<zhouyanjie@wanyeetech.com> a écrit :
> Add SFC support for the X1000 SoC, the X1600 SoC, and the X2000 SoC
> from Ingenic.
> 
> Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
> ---
>  drivers/spi/Kconfig           |   9 +
>  drivers/spi/Makefile          |   1 +
>  drivers/spi/spi-ingenic-sfc.c | 662 
> ++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 672 insertions(+)
>  create mode 100644 drivers/spi/spi-ingenic-sfc.c
> 
> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
> index 3b1044e..1077bd3 100644
> --- a/drivers/spi/Kconfig
> +++ b/drivers/spi/Kconfig
> @@ -437,6 +437,15 @@ config SPI_INGENIC
>  	  To compile this driver as a module, choose M here: the module
>  	  will be called spi-ingenic.
> 
> +config SPI_INGENIC_SFC
> +	tristate "Ingenic SoCs SPI Flash Controller"
> +	depends on MACH_INGENIC || COMPILE_TEST
> +	help
> +	  This enables support for the Ingenic SoCs SPI flash controller.
> +
> +	  To compile this driver as a module, choose M here: the module
> +	  will be called ingenic-sfc.
> +
>  config SPI_INTEL
>  	tristate
> 
> diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
> index 0f44eb6..f3e42c0 100644
> --- a/drivers/spi/Makefile
> +++ b/drivers/spi/Makefile
> @@ -62,6 +62,7 @@ obj-$(CONFIG_SPI_HISI_SFC_V3XX)		+= 
> spi-hisi-sfc-v3xx.o
>  obj-$(CONFIG_SPI_IMG_SPFI)		+= spi-img-spfi.o
>  obj-$(CONFIG_SPI_IMX)			+= spi-imx.o
>  obj-$(CONFIG_SPI_INGENIC)		+= spi-ingenic.o
> +obj-$(CONFIG_SPI_INGENIC_SFC)	+= spi-ingenic-sfc.o
>  obj-$(CONFIG_SPI_INTEL)			+= spi-intel.o
>  obj-$(CONFIG_SPI_INTEL_PCI)		+= spi-intel-pci.o
>  obj-$(CONFIG_SPI_INTEL_PLATFORM)	+= spi-intel-platform.o
> diff --git a/drivers/spi/spi-ingenic-sfc.c 
> b/drivers/spi/spi-ingenic-sfc.c
> new file mode 100644
> index 00000000..a565546
> --- /dev/null
> +++ b/drivers/spi/spi-ingenic-sfc.c
> @@ -0,0 +1,662 @@
> +// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)

Dual-license driver? That's not what MODULE_LICENSE() says.

> +/*
> + * Ingenic SoCs SPI Flash Controller Driver
> + * Copyright (c) 2022 周琰杰 (Zhou Yanjie) 
> <zhouyanjie@wanyeetech.com>
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/bitops.h>
> +#include <linux/clk.h>
> +#include <linux/completion.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/interrupt.h>
> +#include <linux/iopoll.h>
> +#include <linux/module.h>
> +#include <linux/mtd/mtd.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/spi/spi.h>
> +#include <linux/spi/spi-mem.h>
> +
> +/* SFC register offsets */
> +#define SFC_REG_GLB						0x0000
> +#define SFC_REG_DEV_CONF				0x0004
> +#define SFC_REG_DEV_STA_EXP				0x0008
> +#define SFC_REG_DEV_STA_RT				0x000c
> +#define SFC_REG_DEV_STA_MSK				0x0010
> +#define SFC_REG_TRAN_CONF(n)			(0x0014 + n * 4)
> +#define SFC_REG_TRAN_CFG0(n)			(0x0014 + n * 4)

You should protect the macro parameter. If you do for instance 
SFC_REG_TRAN_CONF(x + 1) it would resolve to (0x0014 + x + 1 * 4) which 
is not what you'd want.

Also - looks like SFC_REG_TRAN_CONF() and SFC_REG_TRAN_CFG0() are the 
same thing, that's on purpose?

> +#define SFC_REG_TRAN_LEN				0x002c
> +#define SFC_REG_DEV_ADDR(n)				(0x0030 + n * 4)
> +#define SFC_REG_DEV_ADDR_PLUS(n)		(0x0048 + n * 4)
> +#define SFC_REG_MEM_ADDR				0x0060
> +#define SFC_REG_TRIG					0x0064
> +#define SFC_REG_SR						0x0068
> +#define SFC_REG_SCR						0x006c
> +#define SFC_REG_INTC					0x0070
> +#define SFC_REG_FSM						0x0074
> +#define SFC_REG_CGE						0x0078
> +#define SFC_REG_TRAN_CFG1(n)			(0x009c + n * 4)
> +#define SFC_REG_DR						0x1000
> +
> +/* bits within the GLB register */
> +#define GLB_TRAN_DIR_MASK				GENMASK(13, 13)
> +#define GLB_TRAN_DIR_WRITE				0x1
> +#define GLB_TRAN_DIR_READ				0x0

When it's a single bit - just use BIT().

> +#define GLB_THRESHOLD_MASK				GENMASK(12, 7)
> +#define GLB_OP_MODE_MASK				GENMASK(6, 6)

Same here, and I see it a few times below as well.

> +#define GLB_OP_MODE_DMA					0x1
> +#define GLB_OP_MODE_SLAVE				0x0
> +#define GLB_PHASE_NUM_MASK				GENMASK(5, 3)
> +#define GLB_WP_EN						BIT(2)
> +#define GLB_BURST_MD_MASK				GENMASK(1, 0)
> +#define GLB_BURST_MD_INCR32				0x3
> +#define GLB_BURST_MD_INCR16				0x2
> +#define GLB_BURST_MD_INCR8				0x1
> +#define GLB_BURST_MD_INCR4				0x0
> +
> +/* bits within the DEV_CONF register */
> +#define DEV_CONF_SMP_DELAY_MASK			GENMASK(20, 16)
> +#define DEV_CONF_SMP_DELAY_180DEG		0x4
> +#define DEV_CONF_SMP_DELAY_HALF_CYCLE	0x1
> +#define DEV_CONF_CMD_TYPE_MASK			GENMASK(15, 15)
> +#define DEV_CONF_CMD_TYPE_16BIT			0x1
> +#define DEV_CONF_CMD_TYPE_8BIT			0x0
> +#define DEV_CONF_STA_TYPE_MASK			GENMASK(14, 13)
> +#define DEV_CONF_THOLD_MASK				GENMASK(12, 11)
> +#define DEV_CONF_TSETUP_MASK			GENMASK(10, 9)
> +#define DEV_CONF_TSH_MASK				GENMASK(8, 5)
> +#define DEV_CONF_CPHA					BIT(4)
> +#define DEV_CONF_CPOL					BIT(3)
> +#define DEV_CONF_CE_DL					BIT(2)
> +#define DEV_CONF_HOLD_DL				BIT(1)
> +#define DEV_CONF_WP_DL					BIT(0)
> +
> +/* bits within the TRAN_CONF(n) register */
> +#define TRAN_CONF_TRAN_MODE_MASK		GENMASK(31, 29)
> +#define TRAN_CONF_ADDR_WIDTH_MASK		GENMASK(28, 26)
> +#define TRAN_CONF_POLL_EN				BIT(25)
> +#define TRAN_CONF_CMD_EN				BIT(24)
> +#define TRAN_CONF_PHASE_FORMAT_MASK		GENMASK(23, 23)
> +#define TRAN_CONF_DMY_BITS_MASK			GENMASK(22, 17)
> +#define TRAN_CONF_DATA_EN				BIT(16)
> +#define TRAN_CONF_CMD_MASK				GENMASK(15, 0)
> +
> +/* bits within the TRIG register */
> +#define TRIG_FLUSH						BIT(2)
> +#define TRIG_STOP						BIT(1)
> +#define TRIG_START						BIT(0)
> +
> +/* bits within the SR register */
> +#define SR_FIFO_NUM_MASK				GENMASK(22, 16)
> +#define SR_END							BIT(4)
> +#define SR_TRAN_REQ						BIT(3)
> +#define SR_RECE_REQ						BIT(2)
> +#define SR_OVER							BIT(1)
> +#define SR_UNDER						BIT(0)
> +
> +/* bits within the SCR register */
> +#define SCR_CLR_END						BIT(4)
> +#define SCR_CLR_TREQ					BIT(3)
> +#define SCR_CLR_RREQ					BIT(2)
> +#define SCR_CLR_OVER					BIT(1)
> +#define SCR_CLR_UNDER					BIT(0)
> +
> +/* bits within the INTC register */
> +#define INTC_MASK_END					BIT(4)
> +#define INTC_MASK_TREQ					BIT(3)
> +#define INTC_MASK_RREQ					BIT(2)
> +#define INTC_MASK_OVER					BIT(1)
> +#define INTC_MASK_UNDER					BIT(0)
> +
> +/* bits within the TRAN_CFG1(n) register */
> +#define TRAN_CFG1_TRAN_MODE_MASK		GENMASK(7, 4)
> +
> +#define TRAN_MODE_STANDARD				0
> +#define TRAN_MODE_DUAL_DATA				1
> +#define TRAN_MODE_DUAL_IO				2
> +#define TRAN_MODE_DUAL_FULL				3
> +#define TRAN_MODE_QUAD_DATA				5
> +#define TRAN_MODE_QUAD_IO				6
> +#define TRAN_MODE_QUAD_FULL				7
> +#define TRAN_MODE_OCTAL_DATA			9
> +#define TRAN_MODE_OCTAL_IO				10
> +#define TRAN_MODE_OCTAL_FULL			11
> +
> +#define INGENIC_SFC_FIFO_SIZE			(64 * 4)
> +
> +#define INGENIC_SFC_TRANSFER_TIMEOUT	1000

Maybe add the unit name in the macro as well - 
INGENIC_SFC_TRANSFER_TIMEOUT_MS.

> +
> +enum ingenic_sfc_version {
> +	ID_X1000,
> +	ID_X1600,
> +	ID_X2000,
> +};
> +
> +struct ingenic_soc_info {
> +	enum ingenic_sfc_version version;
> +
> +	unsigned int max_bus_width;
> +
> +	const u32 tran_mode_mask;
> +};
> +
> +struct ingenic_sfc {
> +	const struct ingenic_soc_info *soc_info;
> +
> +	void __iomem *base;
> +	struct device *dev;
> +	struct clk *clk;
> +	int irq;
> +
> +	struct completion completion;
> +};
> +
> +static irqreturn_t ingenic_sfc_irq_handler(int irq, void *data)
> +{
> +	struct ingenic_sfc *sfc = data;
> +
> +	writel(0x1f, sfc->base + SFC_REG_INTC);
> +
> +	complete(&sfc->completion);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int ingenic_sfc_adjust_op_size(struct spi_mem *mem, struct 
> spi_mem_op *op)
> +{
> +	uintptr_t addr = (uintptr_t)op->data.buf.in;
> +
> +	if (op->data.nbytes > INGENIC_SFC_FIFO_SIZE && !IS_ALIGNED(addr, 4))
> +		op->data.nbytes = INGENIC_SFC_FIFO_SIZE;
> +
> +	return 0;
> +}
> +
> +static bool ingenic_sfc_supports_op(struct spi_mem *mem, const 
> struct spi_mem_op *op)
> +{
> +	struct spi_device *spi = mem->spi;
> +	struct ingenic_sfc *sfc = spi_controller_get_devdata(spi->master);
> +	uintptr_t addr = (uintptr_t)op->data.buf.in;
> +
> +	/* The controller only supports Standard SPI mode, Duall mode, Quad 
> mode and Octal mode. */

Dual*

> +	if (op->cmd.buswidth > sfc->soc_info->max_bus_width ||
> +		op->addr.buswidth > sfc->soc_info->max_bus_width ||
> +		op->dummy.buswidth > sfc->soc_info->max_bus_width ||
> +		op->data.buswidth > sfc->soc_info->max_bus_width)
> +		return false;
> +
> +	/* Max 32 dummy clock cycles supported */
> +	if (op->dummy.nbytes && op->dummy.nbytes * 8 / op->dummy.buswidth > 
> 32)
> +		return false;
> +
> +	/* Max rx data length, check controller limits and alignment */
> +	if (op->data.dir == SPI_MEM_DATA_IN &&
> +		op->data.nbytes > INGENIC_SFC_FIFO_SIZE && !IS_ALIGNED(addr, 4))

This does the same check than in ingenic_sfc_adjust_op_size(), maybe 
move it to a new inline function?

> +		return false;
> +
> +	/* Max 6 bytes address width supported */
> +	if (op->addr.nbytes > 6)
> +		return false;
> +
> +	return spi_mem_default_supports_op(mem, op);
> +}
> +
> +static void ingenic_sfc_set_transfer_mode(struct ingenic_sfc *sfc, 
> const struct spi_mem_op *op)
> +{
> +	int val;
> +
> +	val = readl(sfc->base + (sfc->soc_info->version >= ID_X1600 ?
> +			SFC_REG_TRAN_CFG1(0) : SFC_REG_TRAN_CONF(0)));

As Krzysztof said - ugh.

Also, instead of having a "version" enum in your soc_info, why not just 
have a "reg_conf" field that gives you directly the right register?


> +	val &= ~sfc->soc_info->tran_mode_mask;
> +	if (op->cmd.buswidth == 8)
> +		val |= (TRAN_MODE_OCTAL_FULL << 
> (ffs(sfc->soc_info->tran_mode_mask) - 1)) &
> +				sfc->soc_info->tran_mode_mask;

Looks like you're really trying to reinvent the wheel.

val |= FIELD_PREP(sfc->soc_info->tran_mode_mask, TRAN_MODE_OCTAL_FULL);

using <linux/bitfield.h>.

Also, just define a 'mode' variable and set it in your if/else blocks, 
that would look much better. Then you can set val |= FIELD_PREP(..., 
mode) at the end.

> +	else if (op->cmd.buswidth == 4)
> +		val |= (TRAN_MODE_QUAD_FULL << (ffs(sfc->soc_info->tran_mode_mask) 
> - 1)) &
> +				sfc->soc_info->tran_mode_mask;
> +	else if (op->cmd.buswidth == 2)
> +		val |= (TRAN_MODE_DUAL_FULL << (ffs(sfc->soc_info->tran_mode_mask) 
> - 1)) &
> +				sfc->soc_info->tran_mode_mask;
> +	else if (op->addr.buswidth == 8)
> +		val |= (TRAN_MODE_OCTAL_IO << (ffs(sfc->soc_info->tran_mode_mask) 
> - 1)) &
> +				sfc->soc_info->tran_mode_mask;
> +	else if (op->addr.buswidth == 4)
> +		val |= (TRAN_MODE_QUAD_IO << (ffs(sfc->soc_info->tran_mode_mask) - 
> 1)) &
> +				sfc->soc_info->tran_mode_mask;
> +	else if (op->addr.buswidth == 2)
> +		val |= (TRAN_MODE_DUAL_IO << (ffs(sfc->soc_info->tran_mode_mask) - 
> 1)) &
> +				sfc->soc_info->tran_mode_mask;
> +	else if (op->data.buswidth == 8)
> +		val |= (TRAN_MODE_OCTAL_DATA << 
> (ffs(sfc->soc_info->tran_mode_mask) - 1)) &
> +				sfc->soc_info->tran_mode_mask;
> +	else if (op->data.buswidth == 4)
> +		val |= (TRAN_MODE_QUAD_DATA << (ffs(sfc->soc_info->tran_mode_mask) 
> - 1)) &
> +				sfc->soc_info->tran_mode_mask;
> +	else if (op->data.buswidth == 2)
> +		val |= (TRAN_MODE_DUAL_DATA << (ffs(sfc->soc_info->tran_mode_mask) 
> - 1)) &
> +				sfc->soc_info->tran_mode_mask;
> +	else
> +		val |= (TRAN_MODE_STANDARD << (ffs(sfc->soc_info->tran_mode_mask) 
> - 1)) &
> +				sfc->soc_info->tran_mode_mask;
> +	writel(val, sfc->base + (sfc->soc_info->version >= ID_X1600 ?
> +			SFC_REG_TRAN_CFG1(0) : SFC_REG_TRAN_CONF(0)));
> +}
> +
> +/*
> + * We only need PIO mode to handle the SPI_MEM_NO_DATA transfers,
> + * and the unaligned accesses in SPI_MEM_DATA_IN transfers.
> + */
> +static void ingenic_sfc_read_rxfifo(struct ingenic_sfc *sfc, u8 *to, 
> unsigned int len)
> +{
> +	void __iomem *from;
> +
> +	from = sfc->base + SFC_REG_DR;
> +
> +	for (; len >= 4; len -= 4, to += 4) {
> +		u32 val = __raw_readl(from);
> +		memcpy(to, &val, 4);

No need to use memcpy for 4 bytes. You can do: put_unaligned(val, (u32 
*)to);

> +	}
> +
> +	if (len) {
> +		u32 val = __raw_readl(from);
> +		memcpy(to, &val, len);

Hmm, I'm not sure that is endian-safe. I would prefer if you copied 
byte by byte.

> +	}
> +}
> +
> +static int ingenic_sfc_exec_op_pio(struct ingenic_sfc *sfc, const 
> struct spi_mem_op *op)
> +{
> +	int ret, val;
> +
> +	val = readl(sfc->base + SFC_REG_GLB);
> +	u32p_replace_bits(&val, GLB_TRAN_DIR_READ, GLB_TRAN_DIR_MASK);
> +	u32p_replace_bits(&val, GLB_OP_MODE_SLAVE, GLB_OP_MODE_MASK);
> +	writel(val, sfc->base + SFC_REG_GLB);

By the way, have you considered using regmap?

It would give you things like regmap_update_bits() for this kind of 
things, and regmap_field() to handle your conf register being at a 
different address across SoCs.

> +
> +	val = TRAN_CONF_CMD_EN | op->cmd.opcode;
> +
> +	if (op->addr.nbytes > 0) {
> +		val |= FIELD_PREP(TRAN_CONF_ADDR_WIDTH_MASK, op->addr.nbytes);
> +
> +		writel(op->addr.val & 0xffffffff, sfc->base + SFC_REG_DEV_ADDR(0));
> +		writel(op->addr.val >> 32, sfc->base + SFC_REG_DEV_ADDR_PLUS(0));
> +	}
> +
> +	if (op->dummy.nbytes > 0)
> +		val |= FIELD_PREP(TRAN_CONF_DMY_BITS_MASK,
> +				op->dummy.nbytes * 8 / op->dummy.buswidth);
> +
> +	if (op->data.nbytes > 0)
> +		val |= TRAN_CONF_DATA_EN;
> +
> +	writel(val, sfc->base + SFC_REG_TRAN_CONF(0));
> +	writel(op->data.nbytes, sfc->base + SFC_REG_TRAN_LEN);
> +
> +	ingenic_sfc_set_transfer_mode(sfc, op);
> +
> +	writel(0x1f, sfc->base + SFC_REG_SCR);

Random 0x1f value here, maybe use a macro?

> +	writel(~(INTC_MASK_END | INTC_MASK_RREQ), sfc->base + SFC_REG_INTC);
> +
> +	writel(0, sfc->base + SFC_REG_MEM_ADDR);
> +
> +	writel(TRIG_FLUSH, sfc->base + SFC_REG_TRIG);
> +	writel(TRIG_START, sfc->base + SFC_REG_TRIG);
> +
> +	ret = wait_for_completion_timeout(&sfc->completion,
> +			msecs_to_jiffies(INGENIC_SFC_TRANSFER_TIMEOUT));
> +	if (!ret) {
> +		writel(0x1f, sfc->base + SFC_REG_INTC);
> +		writel(0x1f, sfc->base + SFC_REG_SCR);
> +		dev_err(sfc->dev, "line:%d Timeout for ACK from SFC device\n", 
> __LINE__);
> +		return -ETIMEDOUT;
> +	}
> +
> +	ingenic_sfc_read_rxfifo(sfc, op->data.buf.in, op->data.nbytes);
> +	readl_poll_timeout(sfc->base + SFC_REG_SR, val, val & SR_END, 10, 
> 0);

Infinite timeout? Is that very wise?

> +
> +	writel(INTC_MASK_END | INTC_MASK_RREQ, sfc->base + SFC_REG_SCR);
> +	writel(TRIG_STOP, sfc->base + SFC_REG_TRIG);
> +
> +	return 0;
> +}
> +
> +static int ingenic_sfc_exec_op_dma(struct ingenic_sfc *sfc, const 
> struct spi_mem_op *op)
> +{
> +	dma_addr_t addr;
> +	int ret, val;
> +
> +	val = readl(sfc->base + SFC_REG_GLB);
> +	u32p_replace_bits(&val, op->data.dir == SPI_MEM_DATA_IN ?
> +			GLB_TRAN_DIR_READ : GLB_TRAN_DIR_WRITE, GLB_TRAN_DIR_MASK);
> +	u32p_replace_bits(&val, GLB_OP_MODE_DMA, GLB_OP_MODE_MASK);
> +	writel(val, sfc->base + SFC_REG_GLB);
> +
> +	val = TRAN_CONF_CMD_EN | op->cmd.opcode;
> +
> +	if (op->addr.nbytes > 0) {
> +		val |= FIELD_PREP(TRAN_CONF_ADDR_WIDTH_MASK, op->addr.nbytes);
> +		writel(op->addr.val & 0xffffffff, sfc->base + SFC_REG_DEV_ADDR(0));
> +		writel(op->addr.val >> 32, sfc->base + SFC_REG_DEV_ADDR_PLUS(0));
> +	}
> +
> +	if (op->dummy.nbytes > 0)
> +		val |= FIELD_PREP(TRAN_CONF_DMY_BITS_MASK,
> +				op->dummy.nbytes * 8 / op->dummy.buswidth);
> +
> +	if (op->data.nbytes > 0)
> +		val |= TRAN_CONF_DATA_EN;

There's a lot of code duplication here with ingenic_sfc_exec_op_pio(). 
A lot can be factorized.

> +
> +	writel(val, sfc->base + SFC_REG_TRAN_CONF(0));
> +	writel(op->data.nbytes, sfc->base + SFC_REG_TRAN_LEN);
> +
> +	ingenic_sfc_set_transfer_mode(sfc, op);
> +
> +	writel(0x1f, sfc->base + SFC_REG_SCR);
> +	writel(~INTC_MASK_END, sfc->base + SFC_REG_INTC);
> +
> +	switch (op->data.dir) {
> +	case SPI_MEM_DATA_IN:
> +		addr = dma_map_single(sfc->dev, op->data.buf.in, op->data.nbytes, 
> DMA_FROM_DEVICE);
> +		if (dma_mapping_error(sfc->dev, addr)) {
> +			dev_err(sfc->dev, "RX DMA　memory not mapped\n");
> +			return -ENOMEM;
> +		}
> +
> +		writel(addr, sfc->base + SFC_REG_MEM_ADDR);
> +		break;
> +
> +	case SPI_MEM_DATA_OUT:
> +		addr = dma_map_single(sfc->dev, (void *)op->data.buf.out,
> +				op->data.nbytes, DMA_TO_DEVICE);
> +		if (dma_mapping_error(sfc->dev, addr)) {
> +			dev_err(sfc->dev, "TX DMA　memory not mapped\n");
> +			return -ENOMEM;
> +		}
> +
> +		writel(addr, sfc->base + SFC_REG_MEM_ADDR);
> +		break;
> +
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	writel(TRIG_START, sfc->base + SFC_REG_TRIG);
> +
> +	ret = wait_for_completion_timeout(&sfc->completion,
> +			msecs_to_jiffies(INGENIC_SFC_TRANSFER_TIMEOUT));
> +	if (!ret) {
> +		writel(0x1f, sfc->base + SFC_REG_INTC);
> +		writel(0x1f, sfc->base + SFC_REG_SCR);
> +		dev_err(sfc->dev, "line:%d Timeout for ACK from SFC device\n", 
> __LINE__);
> +		return -ETIMEDOUT;
> +	}
> +
> +	dma_unmap_single(sfc->dev, addr, op->data.nbytes,
> +			op->data.dir == SPI_MEM_DATA_IN ? DMA_FROM_DEVICE : 
> DMA_TO_DEVICE);

Use a small inline function for that too. My personal rule is that ?: 
is fine if the line fits in 80 characters, but if you have to break, 
then you really need to move it somewhere else.

> +
> +	writel(INTC_MASK_END, sfc->base + SFC_REG_SCR);
> +	writel(TRIG_STOP, sfc->base + SFC_REG_TRIG);
> +
> +	return 0;
> +}
> +
> +static int ingenic_sfc_exec_op(struct spi_mem *mem, const struct 
> spi_mem_op *op)
> +{
> +	struct spi_device *spi = mem->spi;
> +	struct ingenic_sfc *sfc = spi_controller_get_devdata(spi->master);
> +	uintptr_t addr = (uintptr_t)op->data.buf.in;
> +
> +	init_completion(&sfc->completion);
> +
> +	switch (op->data.dir) {
> +	case SPI_MEM_DATA_IN:
> +		if (sfc->soc_info->version >= ID_X1600 || IS_ALIGNED(addr, 4))
> +			break;
> +
> +		fallthrough;
> +
> +	case SPI_MEM_NO_DATA:
> +		return ingenic_sfc_exec_op_pio(sfc, op);
> +
> +	default:
> +		break;
> +	}
> +
> +	return ingenic_sfc_exec_op_dma(sfc, op);
> +}
> +
> +static int ingenic_sfc_poll_status(struct spi_mem *mem, const struct 
> spi_mem_op *op,
> +			u16 mask, u16 match, unsigned long initial_delay_us,
> +			unsigned long polling_delay_us, unsigned long timeout_ms)
> +{
> +	struct spi_device *spi = mem->spi;
> +	struct ingenic_sfc *sfc = spi_controller_get_devdata(spi->master);
> +	int ret, val;
> +
> +	init_completion(&sfc->completion);
> +
> +	val = readl(sfc->base + SFC_REG_GLB);
> +	u32p_replace_bits(&val, GLB_TRAN_DIR_READ, GLB_TRAN_DIR_MASK);
> +	u32p_replace_bits(&val, GLB_OP_MODE_SLAVE, GLB_OP_MODE_MASK);
> +	writel(val, sfc->base + SFC_REG_GLB);
> +
> +	writel(match, sfc->base + SFC_REG_DEV_STA_EXP);
> +	writel(mask, sfc->base + SFC_REG_DEV_STA_MSK);
> +
> +	val = TRAN_CONF_POLL_EN | TRAN_CONF_CMD_EN | op->cmd.opcode;
> +
> +	if (op->addr.nbytes > 0) {
> +		val |= FIELD_PREP(TRAN_CONF_ADDR_WIDTH_MASK, op->addr.nbytes);
> +
> +		writel(op->addr.val & 0xffffffff, sfc->base + SFC_REG_DEV_ADDR(0));
> +		writel(op->addr.val >> 32, sfc->base + SFC_REG_DEV_ADDR_PLUS(0));
> +	}
> +
> +	if (op->dummy.nbytes > 0)
> +		val |= FIELD_PREP(TRAN_CONF_DMY_BITS_MASK,
> +				op->dummy.nbytes * 8 / op->dummy.buswidth);
> +
> +	if (op->data.nbytes > 0)
> +		val |= TRAN_CONF_DATA_EN;
> +
> +	writel(val, sfc->base + SFC_REG_TRAN_CONF(0));
> +	writel(op->data.nbytes, sfc->base + SFC_REG_TRAN_LEN);
> +
> +	ingenic_sfc_set_transfer_mode(sfc, op);
> +
> +	writel(0x1f, sfc->base + SFC_REG_SCR);
> +	writel(~INTC_MASK_END, sfc->base + SFC_REG_INTC);
> +
> +	writel(0, sfc->base + SFC_REG_MEM_ADDR);
> +
> +	writel(TRIG_START, sfc->base + SFC_REG_TRIG);
> +
> +	ret = wait_for_completion_timeout(&sfc->completion,
> +			msecs_to_jiffies(INGENIC_SFC_TRANSFER_TIMEOUT));
> +	if (!ret) {
> +		writel(0x1f, sfc->base + SFC_REG_INTC);
> +		writel(0x1f, sfc->base + SFC_REG_SCR);
> +		dev_err(sfc->dev, "line:%d Timeout for ACK from SFC device\n", 
> __LINE__);
> +		return -ETIMEDOUT;
> +	}
> +
> +	writel(SCR_CLR_END, sfc->base + SFC_REG_SCR);
> +	writel(TRIG_STOP, sfc->base + SFC_REG_TRIG);
> +
> +	return 0;
> +}
> +
> +static const struct spi_controller_mem_ops ingenic_sfc_mem_ops = {
> +	.adjust_op_size = ingenic_sfc_adjust_op_size,
> +	.supports_op = ingenic_sfc_supports_op,
> +	.exec_op = ingenic_sfc_exec_op,
> +	.poll_status = ingenic_sfc_poll_status,
> +};
> +
> +static int ingenic_sfc_setup(struct spi_device *spi)
> +{
> +	struct ingenic_sfc *sfc = spi_controller_get_devdata(spi->master);
> +	unsigned long rate;
> +	int ret, val;
> +
> +	if (!spi->max_speed_hz)
> +		return -EINVAL;

Maybe set a sane default?

> +
> +	ret = clk_set_rate(sfc->clk, spi->max_speed_hz * 2);
> +	if (ret)
> +		return -EINVAL;
> +
> +	writel(TRIG_STOP, sfc->base + SFC_REG_TRIG);
> +	writel(0, sfc->base + SFC_REG_DEV_CONF);
> +	writel(0, sfc->base + SFC_REG_CGE);
> +
> +	val = readl(sfc->base + SFC_REG_GLB);
> +	u32p_replace_bits(&val, 64 - 1, GLB_THRESHOLD_MASK);
> +	writel(val, sfc->base + SFC_REG_GLB);
> +
> +	val = readl(sfc->base + SFC_REG_DEV_CONF);
> +
> +	/* cpha bit:0 , cpol bit:0 */
> +	val &= ~(DEV_CONF_CPHA | DEV_CONF_CPOL);
> +	val |= spi->mode & SPI_CPHA ? DEV_CONF_CPHA : 0;
> +	val |= spi->mode & SPI_CPOL ? DEV_CONF_CPOL : 0;
> +
> +	/* ce_dl bit:1, hold bit:1, wp bit:1 */
> +	val |= (DEV_CONF_CE_DL | DEV_CONF_HOLD_DL | DEV_CONF_WP_DL);
> +
> +	writel(val, sfc->base + SFC_REG_DEV_CONF);
> +
> +	val = readl(sfc->base + SFC_REG_GLB);
> +	u32p_replace_bits(&val, GLB_OP_MODE_SLAVE, GLB_OP_MODE_MASK);
> +	writel(val, sfc->base + SFC_REG_GLB);
> +
> +	rate = clk_get_rate(sfc->clk);

I'd suggest using clk_round_rate() before clk_set_rate() because then 
you know what frequency it's going to be, and you don't have to call 
clk_get_rate() afterwards.

Cheers,
-Paul

> +	val = readl(sfc->base + SFC_REG_DEV_CONF);
> +	if (sfc->soc_info->version >= ID_X1600 && rate >= 200000000)
> +		u32p_replace_bits(&val, DEV_CONF_SMP_DELAY_180DEG, 
> DEV_CONF_SMP_DELAY_MASK);
> +	else if (sfc->soc_info->version == ID_X1000 && rate >= 100000000)
> +		u32p_replace_bits(&val, DEV_CONF_SMP_DELAY_HALF_CYCLE, 
> DEV_CONF_SMP_DELAY_MASK);
> +	writel(val, sfc->base + SFC_REG_DEV_CONF);
> +
> +	return 0;
> +}
> +
> +static int ingenic_sfc_probe(struct platform_device *pdev)
> +{
> +	struct ingenic_sfc *sfc;
> +	struct spi_controller *ctlr;
> +	int ret;
> +
> +	ctlr = spi_alloc_master(&pdev->dev, sizeof(*sfc));
> +	if (!ctlr)
> +		return -ENOMEM;
> +
> +	sfc = spi_controller_get_devdata(ctlr);
> +
> +	sfc->soc_info = of_device_get_match_data(&pdev->dev);
> +	if (!sfc->soc_info) {
> +		dev_err(&pdev->dev, "No of match data provided\n");
> +		ret = -ENODEV;
> +		goto err_put_master;
> +	}
> +
> +	sfc->base = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(sfc->base)) {
> +		ret = PTR_ERR(sfc->base);
> +		goto err_put_master;
> +	}
> +
> +	sfc->clk = devm_clk_get(&pdev->dev, "sfc");
> +	if (IS_ERR(sfc->clk)) {
> +		ret = IS_ERR(sfc->clk);
> +		goto err_put_master;
> +	}
> +
> +	ret = clk_prepare_enable(sfc->clk);
> +	if (ret)
> +		goto err_put_master;
> +
> +	sfc->irq = platform_get_irq(pdev, 0);
> +	if (sfc->irq < 0) {
> +		ret = sfc->irq;
> +		goto err_put_master;
> +	}
> +
> +	sfc->dev = &pdev->dev;
> +
> +	platform_set_drvdata(pdev, sfc);
> +
> +	ret = devm_request_irq(&pdev->dev, sfc->irq, 
> ingenic_sfc_irq_handler, 0,
> +			dev_name(&pdev->dev), sfc);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to request irq%d, ret = %d\n", 
> sfc->irq, ret);
> +		goto err_put_master;
> +	}
> +
> +	ctlr->bus_num = -1;
> +	ctlr->num_chipselect = 1;
> +	ctlr->mem_ops = &ingenic_sfc_mem_ops;
> +	ctlr->dev.of_node = pdev->dev.of_node;
> +	ctlr->setup = ingenic_sfc_setup;
> +	ctlr->mode_bits = SPI_CPHA | SPI_CPOL |
> +			SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_DUAL | SPI_TX_QUAD;
> +	if (sfc->soc_info->version >= ID_X2000)
> +		ctlr->mode_bits |= SPI_RX_OCTAL | SPI_TX_OCTAL;
> +
> +	ret = devm_spi_register_controller(&pdev->dev, ctlr);
> +	if (ret)
> +		goto err_put_master;
> +
> +	return 0;
> +
> +err_put_master:
> +	spi_master_put(ctlr);
> +
> +	return ret;
> +}
> +
> +static const struct ingenic_soc_info x1000_soc_info = {
> +	.version = ID_X1000,
> +
> +	.max_bus_width = 4,
> +
> +	.tran_mode_mask = TRAN_CONF_TRAN_MODE_MASK,
> +};
> +
> +static const struct ingenic_soc_info x1600_soc_info = {
> +	.version = ID_X1600,
> +
> +	.max_bus_width = 4,
> +
> +	.tran_mode_mask = TRAN_CONF_TRAN_MODE_MASK,
> +};
> +
> +static const struct ingenic_soc_info x2000_soc_info = {
> +	.version = ID_X2000,
> +
> +	.max_bus_width = 8,
> +
> +	.tran_mode_mask = TRAN_CFG1_TRAN_MODE_MASK,
> +};
> +
> +static const struct of_device_id ingenic_sfc_of_matches[] = {
> +	{ .compatible = "ingenic,x1000-sfc", .data = &x1000_soc_info },
> +	{ .compatible = "ingenic,x1600-sfc", .data = &x1600_soc_info },
> +	{ .compatible = "ingenic,x2000-sfc", .data = &x2000_soc_info },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, ingenic_sfc_of_matches);
> +
> +static struct platform_driver ingenic_sfc_driver = {
> +	.driver = {
> +		.name = "ingenic-sfc",
> +		.of_match_table = ingenic_sfc_of_matches,
> +	},
> +	.probe = ingenic_sfc_probe,
> +};
> +module_platform_driver(ingenic_sfc_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>");
> +MODULE_DESCRIPTION("Ingenic SoCs SPI Flash Controller Driver");
> --
> 2.7.4
> 



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