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From: Zhou Yanjie <zhouyanjie@wanyeetech.com>
To: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
	tudor.ambarus@microchip.com, p.yadav@ti.com, michael@walle.cc,
	miquel.raynal@bootlin.com, richard@nod.at, vigneshr@ti.com,
	broonie@kernel.org, robh+dt@kernel.org,
	krzysztof.kozlowski+dt@linaro.org
Cc: linux-mtd@lists.infradead.org, linux-spi@vger.kernel.org,
	linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org,
	devicetree@vger.kernel.org, aidanmacdonald.0x0@gmail.com,
	tmn505@gmail.com, paul@crapouillou.net,
	dongsheng.qiu@ingenic.com, aric.pzqi@ingenic.com,
	rick.tyliu@ingenic.com, jinghui.liu@ingenic.com,
	sernia.zhou@foxmail.com, reimu@sudomaker.com
Subject: Re: [PATCH 3/3] SPI: Ingenic: Add SFC support for Ingenic SoCs.
Date: Sun, 24 Jul 2022 00:53:10 +0800	[thread overview]
Message-ID: <4904a283-8ede-3147-078a-b64318513b07@wanyeetech.com> (raw)
In-Reply-To: <1a0245c3-5659-573a-c74d-c2145a564b76@linaro.org>

Hi Krzysztof,

On 2022/7/23 上午2:07, Krzysztof Kozlowski wrote:
> On 22/07/2022 18:48, 周琰杰 (Zhou Yanjie) wrote:
>> 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)
>> +/*
>> + * 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)
>> +#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
>> +#define GLB_THRESHOLD_MASK				GENMASK(12, 7)
>> +#define GLB_OP_MODE_MASK				GENMASK(6, 6)
>> +#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
>> +
>> +enum ingenic_sfc_version {
>> +	ID_X1000,
>> +	ID_X1600,
>> +	ID_X2000,
>> +};
>> +
>> +struct ingenic_soc_info {
>> +	enum ingenic_sfc_version version;
>> +
> No need for blank line.
>
>> +	unsigned int max_bus_width;
>> +
> Remove as well.
>
>> +	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. */
>> +	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))
>> +		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)));
> This is no really readable.


Sure, I will change it in the next version.


>> +	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;
>> +	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)));
> Not readable.


Will change it.


>
>> +}
>> +
>> +/*
>> + * We only need PIO mode to handle the SPI_MEM_NO_DATA transfers,
>> + * and the unaligned accesses in SPI_MEM_DATA_IN transfers.
>> + */
> (...)
>
>> +	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);
> What about unpreparing clocks? Is it part of spi_master_put()?


Will add it in the next version.


Thanks and beset regards!


>> +
>> +	return ret;
>> +}
>> +
>> +static const struct ingenic_soc_info x1000_soc_info = {
>> +	.version = ID_X1000,
>> +
> No need for blank lines after each field.
>
>
> Best regards,
> Krzysztof

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  reply	other threads:[~2022-07-23 16:53 UTC|newest]

Thread overview: 39+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-07-22 16:48 [PATCH 0/3] Add SFC support for Ingenic SoCs 周琰杰 (Zhou Yanjie)
2022-07-22 16:48 ` [PATCH 1/3] mtd: spi-nor: Use the spi-mem poll status APIs 周琰杰 (Zhou Yanjie)
2022-07-23  8:30   ` Sergey Shtylyov
2022-07-22 16:48 ` [PATCH 2/3] dt-bindings: SPI: Add Ingenic SFC bindings 周琰杰 (Zhou Yanjie)
2022-07-22 17:46   ` Krzysztof Kozlowski
2022-07-23 16:50     ` Zhou Yanjie
2022-07-23 17:43       ` Krzysztof Kozlowski
2022-07-23 18:47         ` Mike Yang
2022-07-23 19:27           ` Mark Brown
2022-07-23 20:07             ` Krzysztof Kozlowski
2022-07-23 20:49               ` Mike Yang
2022-07-24 15:33                 ` Zhou Yanjie
2022-07-25 18:30                 ` Rob Herring
2022-07-23 20:05           ` Krzysztof Kozlowski
2022-07-24 14:52             ` Zhou Yanjie
2022-07-22 22:44   ` Rob Herring
2022-07-22 16:48 ` [PATCH 3/3] SPI: Ingenic: Add SFC support for Ingenic SoCs 周琰杰 (Zhou Yanjie)
2022-07-22 18:07   ` Krzysztof Kozlowski
2022-07-23 16:53     ` Zhou Yanjie [this message]
2022-07-22 18:38   ` Mark Brown
2022-07-23 17:06     ` Zhou Yanjie
2022-07-23 19:32       ` Mark Brown
2022-07-24  1:24         ` Zhou Yanjie
2022-07-22 20:03   ` Paul Cercueil
2022-07-23 17:26     ` Zhou Yanjie
2022-07-23 20:24       ` Paul Cercueil
2022-07-24 15:29         ` Zhou Yanjie
2022-07-23 15:15   ` Christophe JAILLET
2022-07-23 15:15     ` Christophe JAILLET
2022-07-24  1:22     ` Zhou Yanjie
2022-07-24  0:43   ` kernel test robot
2022-07-24  1:28     ` Vanessa Page
2022-07-23 14:47 ` [PATCH 0/3] " Tomasz Maciej Nowak
2022-07-24  1:25   ` Zhou Yanjie
2022-07-24  1:28     ` Vanessa Page
2022-07-24  1:28     ` Vanessa Page
2022-07-24  1:30     ` Vanessa Page
2022-07-24  1:32       ` Vee Page
2022-07-26  6:13         ` Vee Page

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