Date:   Mon, 29 Aug 2022 11:27:40 +0300
From:   Ivan Bornyakov <i.bornyakov@...rotek.ru>
To:     Xu Yilun <yilun.xu@...el.com>
Cc:     mdf@...nel.org, hao.wu@...el.com, trix@...hat.com, dg@...ix.com,
        robh+dt@...nel.org, krzysztof.kozlowski+dt@...aro.org,
        linux-fpga@...r.kernel.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org, system@...rotek.ru
Subject: Re: [PATCH v8 1/2] fpga: lattice-sysconfig-spi: add Lattice
 sysCONFIG FPGA manager

On Mon, Aug 29, 2022 at 03:25:41PM +0800, Xu Yilun wrote:
> On 2022-08-25 at 14:24:32 +0300, Ivan Bornyakov wrote:
> > Add support to the FPGA manager for programming Lattice ECP5 and MachXO2
> > FPGAs over slave SPI sysCONFIG interface.
> > 
> > Signed-off-by: Ivan Bornyakov <i.bornyakov@...rotek.ru>
> > ---
> >  drivers/fpga/Kconfig                 |   7 +
> >  drivers/fpga/Makefile                |   1 +
> >  drivers/fpga/lattice-sysconfig-spi.c | 630 +++++++++++++++++++++++++++
> >  3 files changed, 638 insertions(+)
> >  create mode 100644 drivers/fpga/lattice-sysconfig-spi.c
> > 
> > diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
> > index 6c416955da53..991d9d976dca 100644
> > --- a/drivers/fpga/Kconfig
> > +++ b/drivers/fpga/Kconfig
> > @@ -263,4 +263,11 @@ config FPGA_MGR_MICROCHIP_SPI
> >  	  programming over slave SPI interface with .dat formatted
> >  	  bitstream image.
> >  
> > +config FPGA_MGR_LATTICE_SPI
> > +	tristate "Lattice sysCONFIG SPI FPGA manager"
> > +	depends on SPI
> > +	help
> > +	  FPGA manager driver support for Lattice FPGAs programming over slave
> > +	  SPI sysCONFIG interface.
> > +
> >  endif # FPGA
> > diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
> > index 42ae8b58abce..115dba916024 100644
> > --- a/drivers/fpga/Makefile
> > +++ b/drivers/fpga/Makefile
> > @@ -20,6 +20,7 @@ obj-$(CONFIG_FPGA_MGR_ZYNQ_FPGA)	+= zynq-fpga.o
> >  obj-$(CONFIG_FPGA_MGR_ZYNQMP_FPGA)	+= zynqmp-fpga.o
> >  obj-$(CONFIG_FPGA_MGR_VERSAL_FPGA)	+= versal-fpga.o
> >  obj-$(CONFIG_FPGA_MGR_MICROCHIP_SPI)	+= microchip-spi.o
> > +obj-$(CONFIG_FPGA_MGR_LATTICE_SPI)	+= lattice-sysconfig-spi.o
> >  obj-$(CONFIG_ALTERA_PR_IP_CORE)		+= altera-pr-ip-core.o
> >  obj-$(CONFIG_ALTERA_PR_IP_CORE_PLAT)	+= altera-pr-ip-core-plat.o
> >  
> > diff --git a/drivers/fpga/lattice-sysconfig-spi.c b/drivers/fpga/lattice-sysconfig-spi.c
> > new file mode 100644
> > index 000000000000..145b5b27b88d
> > --- /dev/null
> > +++ b/drivers/fpga/lattice-sysconfig-spi.c
> > @@ -0,0 +1,630 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Lattice FPGA programming over slave SPI sysCONFIG interface.
> > + */
> > +
> > +#include <linux/delay.h>
> > +#include <linux/fpga/fpga-mgr.h>
> > +#include <linux/of_device.h>
> > +#include <linux/spi/spi.h>
> > +
> > +#define	SYSCONFIG_ISC_ENABLE		{0xC6, 0x00, 0x00, 0x00}
> > +#define	SYSCONFIG_ISC_DISABLE		{0x26, 0x00, 0x00, 0x00}
> > +#define	SYSCONFIG_ISC_ERASE		{0x0E, 0x00, 0x00, 0x00}
> > +#define	SYSCONFIG_ISC_PROGRAM_DONE	{0x5E, 0x00, 0x00, 0x00}
> > +#define	SYSCONFIG_LSC_READ_STATUS	{0x3C, 0x00, 0x00, 0x00}
> > +#define	SYSCONFIG_LSC_CHECK_BUSY	{0xF0, 0x00, 0x00, 0x00}
> > +#define	SYSCONFIG_LSC_REFRESH		{0x79, 0x00, 0x00, 0x00}
> > +#define	SYSCONFIG_LSC_INIT_ADDR		{0x46, 0x00, 0x00, 0x00}
> > +#define	SYSCONFIG_LSC_BITSTREAM_BURST	{0x7a, 0x00, 0x00, 0x00}
> > +#define	SYSCONFIG_LSC_PROG_INCR_NV	{0x70, 0x00, 0x00, 0x01}
> > +
> > +#define	SYSCONFIG_STATUS_DONE		BIT(8)
> > +#define	SYSCONFIG_STATUS_BUSY		BIT(12)
> > +#define	SYSCONFIG_STATUS_FAIL		BIT(13)
> > +#define	SYSCONFIG_STATUS_ERR		(BIT(23) | BIT(24) | BIT(25))
> > +
> > +#define	SYSCONFIG_POLL_RETRIES		100000
> > +
> > +#define	ECP5_SPI_MAX_SPEED_HZ		60000000
> > +#define	ECP5_ISC_ERASE_OPERAND		0x01
> > +
> > +#define	MACHXO2_SPI_MAX_SPEED_HZ	66000000
> > +#define	MACHXO2_PAGE_SIZE		16
> > +#define	MACHXO2_ISC_ENABLE_OPERAND	0x08
> > +#define	MACHXO2_ISC_ERASE_OPERAND	0x04
> 
> You need to deliver the meaning of each operand, rather than just point
> out this is for machxo2, that is for esp5. I assume the sysCONFIG will
> not deliberately design different commands with the exact same
> functionality for different boards.
> 
> We should have a set of common configurations with finer granularity that
> board specific fpga manager device could select from, rather than create
> more and more similar macros for each new board.
> 
> Back to the 2 operands, what's the meaning of 0x1 & 0x4 for erase,

0x1 - erase SRAM, 0x4 - erase FLASH. I'll redefine them properly in v9

> also 0x0 & 0x8 for enable?
> 

Their meaning is not documented. It's just 0x08 for MachXO2 and 0x00 for
ECP5.

> > +
> > +struct sysconfig_priv {
> > +	struct gpio_desc *program;
> > +	struct gpio_desc *init;
> > +	struct gpio_desc *done;
> > +	struct spi_device *spi;
> > +	u8 isc_enable_operand;
> > +	u8 isc_erase_operand;
> > +};
> > +
> > +static int sysconfig_poll_busy(struct sysconfig_priv *data)
> > +{
> > +	const u8 lsc_check_busy[] = SYSCONFIG_LSC_CHECK_BUSY;
> > +	int ret, retries = SYSCONFIG_POLL_RETRIES;
> > +	u8 busy;
> > +
> > +	while (retries--) {
> > +		ret = spi_write_then_read(data->spi,
> > +					  lsc_check_busy, sizeof(lsc_check_busy),
> > +					  &busy, sizeof(busy));
> > +		if (ret)
> > +			return ret;
> > +
> > +		if (!busy)
> > +			return 0;
> > +
> > +		usleep_range(50, 100);
> > +	}
> > +
> > +	return -EBUSY;
> > +}
> > +
> > +static int sysconfig_read_status(struct sysconfig_priv *data, u32 *status)
> > +{
> > +	const u8 lsc_read_status[] = SYSCONFIG_LSC_READ_STATUS;
> > +	__be32 device_status;
> > +	int ret;
> > +
> > +	ret = spi_write_then_read(data->spi,
> > +				  lsc_read_status, sizeof(lsc_read_status),
> > +				  &device_status, sizeof(device_status));
> > +	if (ret)
> > +		return ret;
> > +
> > +	*status = be32_to_cpu(device_status);
> > +
> > +	return 0;
> > +}
> > +
> > +static int sysconfig_poll_status(struct sysconfig_priv *data, u32 *status)
> > +{
> > +	int ret;
> > +
> > +	ret = sysconfig_poll_busy(data);
> > +	if (ret)
> > +		return ret;
> > +
> > +	return sysconfig_read_status(data, status);
> > +}
> > +
> > +static int sysconfig_poll_gpio(struct gpio_desc *gpio, bool is_active)
> > +{
> > +	int value, retries = SYSCONFIG_POLL_RETRIES;
> > +
> > +	while (retries--) {
> > +		value = gpiod_get_value(gpio);
> > +		if (value < 0)
> > +			return value;
> > +
> > +		if ((!is_active && !value) || (is_active && value))
> > +			return 0;
> > +
> > +		ndelay(10);
> > +	}
> > +
> > +	return -ETIMEDOUT;
> > +}
> > +
> > +static int sysconfig_refresh(struct sysconfig_priv *data)
> > +{
> > +	static const u8 lsc_refresh[] = SYSCONFIG_LSC_REFRESH;
> > +	int ret;
> > +
> > +	ret = spi_write(data->spi, lsc_refresh, sizeof(lsc_refresh));
> > +	if (ret)
> > +		return ret;
> > +
> > +	usleep_range(4000, 8000);
> > +
> > +	return 0;
> > +}
> > +
> > +static int sysconfig_isc_enable(struct sysconfig_priv *data)
> > +{
> > +	u8 isc_enable[] = SYSCONFIG_ISC_ENABLE;
> > +	u32 status;
> > +	int ret;
> > +
> > +	isc_enable[1] = data->isc_enable_operand;
> > +
> > +	ret = spi_write(data->spi, isc_enable, sizeof(isc_enable));
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = sysconfig_poll_status(data, &status);
> > +	if (ret || (status & SYSCONFIG_STATUS_FAIL))
> > +		return ret ? : -EFAULT;
> > +
> > +	return 0;
> > +}
> > +
> > +static int sysconfig_isc_erase(struct sysconfig_priv *data)
> > +{
> > +	u8 isc_erase[] = SYSCONFIG_ISC_ERASE;
> > +	u32 status;
> > +	int ret;
> > +
> > +	isc_erase[1] = data->isc_erase_operand;
> > +
> > +	ret = spi_write(data->spi, isc_erase, sizeof(isc_erase));
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = sysconfig_poll_status(data, &status);
> > +	if (ret || (status & SYSCONFIG_STATUS_FAIL))
> > +		return ret ? : -EFAULT;
> > +
> > +	return 0;
> > +}
> > +
> > +static int sysconfig_isc_init(struct sysconfig_priv *data)
> > +{
> > +	int ret;
> > +
> > +	ret = sysconfig_isc_enable(data);
> > +	if (ret)
> > +		return ret;
> > +
> > +	return sysconfig_isc_erase(data);
> > +}
> > +
> > +static int sysconfig_lsc_init_addr(struct sysconfig_priv *data)
> > +{
> > +	const u8 lsc_init_addr[] = SYSCONFIG_LSC_INIT_ADDR;
> > +
> > +	return spi_write(data->spi, lsc_init_addr, sizeof(lsc_init_addr));
> > +}
> > +
> > +static int sysconfig_lsc_bitstream_burst(struct sysconfig_priv *data)
> > +{
> > +	const u8 lsc_bitstream_burst[] = SYSCONFIG_LSC_BITSTREAM_BURST;
> > +	struct spi_transfer xfer = {
> > +		.tx_buf = lsc_bitstream_burst,
> > +		.len = sizeof(lsc_bitstream_burst),
> > +		.cs_change = 1,
> > +	};
> > +	struct spi_message msg;
> > +
> > +	spi_message_init_with_transfers(&msg, &xfer, 1);
> > +
> > +	return spi_sync_locked(data->spi, &msg);
> > +}
> > +
> > +static int sysconfig_isc_prog_done(struct sysconfig_priv *data)
> > +{
> > +	const u8 isc_prog_done[] = SYSCONFIG_ISC_PROGRAM_DONE;
> > +	u32 status;
> > +	int ret;
> > +
> > +	ret = spi_write(data->spi, isc_prog_done, sizeof(isc_prog_done));
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = sysconfig_poll_status(data, &status);
> > +	if (ret)
> > +		return ret;
> > +
> > +	if (status & SYSCONFIG_STATUS_DONE)
> > +		return 0;
> > +
> > +	return -EFAULT;
> > +}
> > +
> > +static int sysconfig_isc_disable(struct sysconfig_priv *data)
> > +{
> > +	const u8 isc_disable[] = SYSCONFIG_ISC_DISABLE;
> > +
> > +	return spi_write(data->spi, isc_disable, sizeof(isc_disable));
> > +}
> > +
> > +static enum fpga_mgr_states ecp5_ops_state(struct fpga_manager *mgr)
> > +{
> > +	struct sysconfig_priv *priv = mgr->priv;
> > +
> > +	return (gpiod_get_value(priv->done) > 0) ? FPGA_MGR_STATE_OPERATING :
> > +						   FPGA_MGR_STATE_UNKNOWN;
> > +}
> > +
> > +static int ecp5_ops_write_init(struct fpga_manager *mgr,
> > +			       struct fpga_image_info *info,
> > +			       const char *buf, size_t count)
> > +{
> > +	struct sysconfig_priv *priv = mgr->priv;
> > +	struct spi_device *spi = priv->spi;
> > +	struct device *dev = &mgr->dev;
> > +	struct gpio_desc *program;
> > +	struct gpio_desc *init;
> > +	struct gpio_desc *done;
> > +	int ret;
> > +
> > +	if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) {
> > +		dev_err(dev, "Partial reconfiguration is not supported\n");
> > +		return -EOPNOTSUPP;
> > +	}
> > +
> > +	program = priv->program;
> > +	init = priv->init;
> > +	done = priv->done;
> > +
> > +	/* Enter init mode */
> > +	gpiod_set_value(program, 1);
> 
> Same concern, provide gpio or command options for all board specific
> fpga manager to select. 
> 
> I'll not list each features one by one below.
> 
> some more comments below.
> 
> > +
> > +	ret = sysconfig_poll_gpio(init, true);
> > +	if (!ret)
> > +		ret = sysconfig_poll_gpio(done, false);
> > +
> > +	if (ret) {
> > +		dev_err(dev, "Failed to go to init mode\n");
> > +		return ret;
> > +	}
> > +
> > +	/* Enter program mode */
> > +	gpiod_set_value(program, 0);
> > +
> > +	ret = sysconfig_poll_gpio(init, false);
> > +	if (ret) {
> > +		dev_err(dev, "Failed to go to program mode\n");
> > +		return ret;
> > +	}
> > +
> > +	/* Enter ISC mode */
> > +	ret = sysconfig_isc_init(priv);
> > +	if (ret) {
> > +		dev_err(dev, "Failed to go to ISC mode\n");
> > +		return ret;
> > +	}
> > +
> > +	/* Initialize the Address Shift Register */
> > +	ret = sysconfig_lsc_init_addr(priv);
> > +	if (ret) {
> > +		dev_err(dev,
> > +			"Failed to initialize the Address Shift Register\n");
> > +		return ret;
> > +	}
> > +
> > +	/*
> > +	 * Lock SPI bus for exclusive usage until FPGA programming is done.
> > +	 * SPI bus will be released in ecp5_ops_write_complete() or on error.
> > +	 */
> > +	spi_bus_lock(spi->controller);
> > +
> > +	/* Prepare for bitstream burst write */
> > +	ret = sysconfig_lsc_bitstream_burst(priv);
> > +	if (ret) {
> > +		dev_err(dev, "Failed to prepare for bitstream burst write\n");
> > +		spi_bus_unlock(spi->controller);
> > +	}
> > +
> > +	return ret;
> > +}
> > +
> > +static int ecp5_ops_write(struct fpga_manager *mgr, const char *buf, size_t count)
> > +{
> > +	struct sysconfig_priv *priv = mgr->priv;
> > +	struct spi_device *spi = priv->spi;
> > +	struct spi_transfer xfer = {
> > +		.tx_buf = buf,
> > +		.len = count,
> > +		.cs_change = 1,
> > +	};
> > +	struct spi_message msg;
> > +	int ret;
> > +
> > +	spi_message_init_with_transfers(&msg, &xfer, 1);
> > +	ret = spi_sync_locked(spi, &msg);
> > +	if (ret)
> > +		spi_bus_unlock(spi->controller);
> > +
> > +	return ret;
> > +}
> > +
> > +static int ecp5_ops_write_complete(struct fpga_manager *mgr,
> > +				   struct fpga_image_info *info)
> > +{
> > +	struct sysconfig_priv *priv = mgr->priv;
> > +	struct spi_device *spi = priv->spi;
> > +	struct device *dev = &mgr->dev;
> > +	int ret;
> > +
> > +	/* Bitstream burst write is done, release SPI bus */
> > +	spi_bus_unlock(spi->controller);
> > +
> > +	/* Toggle CS and wait for bitstream write to finish */
> > +	ret = spi_write(spi, NULL, 0);
> > +	if (!ret)
> > +		ret = sysconfig_poll_busy(priv);
> > +
> > +	if (ret) {
> > +		dev_err(dev, "Error while waiting bitstream write to finish\n");
> > +		return ret;
> > +	}
> > +
> > +	/* Exit ISC mode */
> > +	ret = sysconfig_isc_disable(priv);
> > +	if (!ret)
> > +		ret = sysconfig_poll_gpio(priv->done, true);
> > +
> > +	if (ret)
> > +		dev_err(dev, "Failed to finish ISC\n");
> > +
> > +	return ret;
> > +}
> > +
> > +static const struct fpga_manager_ops ecp5_fpga_ops = {
> > +	.state = ecp5_ops_state,
> > +	.write_init = ecp5_ops_write_init,
> > +	.write = ecp5_ops_write,
> > +	.write_complete = ecp5_ops_write_complete,
> > +};
> > +
> > +static int ecp5_probe(struct sysconfig_priv *priv)
> > +{
> > +	struct spi_device *spi = priv->spi;
> > +	struct device *dev = &spi->dev;
> > +	struct fpga_manager *mgr;
> > +	int ret;
> > +
> > +	if (spi->max_speed_hz > ECP5_SPI_MAX_SPEED_HZ) {
> > +		dev_err(dev, "SPI speed %u is too high, maximum speed is %u\n",
> > +			spi->max_speed_hz, ECP5_SPI_MAX_SPEED_HZ);
> > +		return -EINVAL;
> > +	}
> > +
> > +	priv->isc_erase_operand = ECP5_ISC_ERASE_OPERAND;
> > +
> > +	priv->done = devm_gpiod_get(dev, "done", GPIOD_IN);
> > +	if (IS_ERR(priv->done)) {
> > +		ret = PTR_ERR(priv->done);
> > +		dev_err(dev, "Failed to get DONE GPIO: %d\n", ret);
> > +		return ret;
> > +	}
> > +
> > +	priv->init = devm_gpiod_get(dev, "init", GPIOD_IN);
> > +	if (IS_ERR(priv->init)) {
> > +		ret = PTR_ERR(priv->init);
> > +		dev_err(dev, "Failed to get INIT GPIO: %d\n", ret);
> > +		return ret;
> > +	}
> > +
> > +	priv->program = devm_gpiod_get(dev, "program", GPIOD_OUT_LOW);
> > +	if (IS_ERR(priv->program)) {
> > +		ret = PTR_ERR(priv->program);
> > +		dev_err(dev, "Failed to get PROGRAM GPIO: %d\n", ret);
> > +		return ret;
> > +	}
> > +
> > +	mgr = devm_fpga_mgr_register(dev, "Lattice ECP5 SPI FPGA Manager",
> > +				     &ecp5_fpga_ops, priv);
> > +
> > +	return PTR_ERR_OR_ZERO(mgr);
> > +}
> > +
> > +static enum fpga_mgr_states machxo2_ops_state(struct fpga_manager *mgr)
> > +{
> > +	struct sysconfig_priv *priv = mgr->priv;
> > +	u32 status;
> > +	int ret;
> > +
> > +	ret = sysconfig_read_status(priv, &status);
> > +	if (ret || !(status & SYSCONFIG_STATUS_DONE))
> > +		return FPGA_MGR_STATE_UNKNOWN;
> > +
> > +	return FPGA_MGR_STATE_OPERATING;
> > +}
> > +
> > +static int machxo2_ops_write_init(struct fpga_manager *mgr,
> > +				  struct fpga_image_info *info,
> > +				  const char *buf, size_t count)
> > +{
> > +	struct sysconfig_priv *priv = mgr->priv;
> > +	struct device *dev = &mgr->dev;
> > +	int ret;
> > +
> > +	if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) {
> > +		dev_err(dev, "Partial reconfiguration is not supported\n");
> > +		return -EOPNOTSUPP;
> > +	}
> > +
> > +	/* Enter ISC mode */
> > +	ret = sysconfig_isc_init(priv);
> > +	if (ret) {
> > +		dev_err(dev, "Failed to go to ISC mode\n");
> > +		return ret;
> > +	}
> > +
> > +	/* Initialize the Address Shift Register */
> > +	ret = sysconfig_lsc_init_addr(priv);
> > +	if (ret)
> > +		dev_err(dev,
> > +			"Failed to initialize the Address Shift Register\n");
> > +
> > +	return ret;
> > +}
> > +
> > +static int machxo2_ops_write(struct fpga_manager *mgr, const char *buf, size_t count)
> > +{
> > +	const u8 lsc_progincr[] = SYSCONFIG_LSC_PROG_INCR_NV;
> > +	struct sysconfig_priv *priv = mgr->priv;
> > +	struct device *dev = &mgr->dev;
> > +	struct spi_transfer xfers[2] = {
> > +		{
> > +			.tx_buf = lsc_progincr,
> > +			.len = sizeof(lsc_progincr),
> > +		}, {
> > +			.len = MACHXO2_PAGE_SIZE,
> > +		},
> > +	};
> > +	size_t i;
> > +	int ret;
> > +
> > +	if (count % MACHXO2_PAGE_SIZE) {
> > +		dev_err(dev, "Malformed payload.\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	for (i = 0; i < count; i += MACHXO2_PAGE_SIZE) {
> > +		xfers[1].tx_buf = buf + i;
> > +
> > +		ret = spi_sync_transfer(priv->spi, xfers, 2);
> > +		if (!ret)
> > +			ret = sysconfig_poll_busy(priv);
> > +
> > +		if (ret) {
> > +			dev_err(dev, "Failed to write frame %zu of %zu\n",
> > +				i / MACHXO2_PAGE_SIZE, count / MACHXO2_PAGE_SIZE);
> > +			return ret;
> > +		}
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static void machxo2_cleanup(struct sysconfig_priv *data)
> > +{
> > +	sysconfig_isc_erase(data);
> > +	sysconfig_refresh(data);
> > +}
> > +
> > +static int machxo2_ops_write_complete(struct fpga_manager *mgr,
> > +				      struct fpga_image_info *info)
> > +{
> > +	int ret, retries = SYSCONFIG_POLL_RETRIES;
> > +	struct sysconfig_priv *priv = mgr->priv;
> > +	struct device *dev = &mgr->dev;
> > +	u32 status;
> > +
> > +	ret = sysconfig_isc_prog_done(priv);
> > +	if (ret) {
> > +		dev_err(dev, "Failed to enable Self-Download Mode\n");
> > +		goto fail;
> > +	}
> > +
> > +	ret = sysconfig_isc_disable(priv);
> > +	if (ret) {
> > +		dev_err(dev, "Failed to disable Configuration Interface\n");
> > +		goto fail;
> > +	}
> > +
> > +	while (retries--) {
> > +		ret = sysconfig_refresh(priv);
> > +		if (!ret)
> > +			ret = sysconfig_read_status(priv, &status);
> > +
> > +		if (ret) {
> > +			dev_err(dev, "Failed to refresh\n");
> > +			break;
> > +		}
> > +
> > +		if (status & SYSCONFIG_STATUS_DONE &&
> > +		    !(status & SYSCONFIG_STATUS_BUSY) &&
> > +		    !(status & SYSCONFIG_STATUS_ERR))
> > +			return 0;
> > +	}
> > +
> > +fail:
> > +	machxo2_cleanup(priv);
> > +
> > +	return -EFAULT;
> > +}
> > +
> > +static const struct fpga_manager_ops machxo2_fpga_ops = {
> > +	.state = machxo2_ops_state,
> > +	.write_init = machxo2_ops_write_init,
> > +	.write = machxo2_ops_write,
> > +	.write_complete = machxo2_ops_write_complete,
> > +};
> > +
> > +static int machxo2_probe(struct sysconfig_priv *priv)
> > +{
> > +	struct spi_device *spi = priv->spi;
> > +	struct device *dev = &spi->dev;
> > +	struct fpga_manager *mgr;
> > +
> > +	if (spi->max_speed_hz > MACHXO2_SPI_MAX_SPEED_HZ) {
> > +		dev_err(dev, "SPI speed %u is too high, maximum speed is %u\n",
> > +			spi->max_speed_hz, MACHXO2_SPI_MAX_SPEED_HZ);
> > +		return -EINVAL;
> > +	}
> > +
> > +	priv->isc_enable_operand = MACHXO2_ISC_ENABLE_OPERAND;
> > +	priv->isc_erase_operand = MACHXO2_ISC_ERASE_OPERAND;
> > +
> > +	mgr = devm_fpga_mgr_register(dev, "Lattice MachXO2 SPI FPGA Manager",
> > +				     &machxo2_fpga_ops, priv);
> > +
> > +	return PTR_ERR_OR_ZERO(mgr);
> > +}
> > +
> > +typedef int (*lattice_fpga_probe_func)(struct sysconfig_priv *);
> > +
> > +static int sysconfig_probe(struct spi_device *spi)
> > +{
> > +	const struct spi_device_id *dev_id;
> > +	lattice_fpga_probe_func probe_func;
> > +	struct device *dev = &spi->dev;
> > +	struct sysconfig_priv *priv;
> > +
> > +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> > +	if (!priv)
> > +		return -ENOMEM;
> > +
> > +	priv->spi = spi;
> > +
> > +	probe_func = of_device_get_match_data(&spi->dev);
> > +	if (!probe_func) {
> > +		dev_id = spi_get_device_id(spi);
> > +		if (!dev_id)
> > +			return -ENODEV;
> > +
> > +		probe_func = (lattice_fpga_probe_func)dev_id->driver_data;
> > +	}
> > +
> > +	if (!probe_func)
> > +		return -EINVAL;
> > +
> > +	return probe_func(priv);
> > +}
> > +
> > +static const struct spi_device_id sysconfig_spi_ids[] = {
> > +	{
> > +		.name = "ecp5-fpga-mgr",
> > +		.driver_data = (kernel_ulong_t)ecp5_probe,
> > +	}, {
> > +		.name = "machxo2-fpga-mgr",
> > +		.driver_data = (kernel_ulong_t)machxo2_probe,
> 
> Putting the whole probe flow in driver_data is the same as providing 2
> drivers. The purpose is not to put all the code in one file.
> 

Sorry, I don't understand what you suggest. Separate file for each
specific FPGA?

> Thanks,
> Yilun
> 
> > +	}, {},
> > +};
> > +MODULE_DEVICE_TABLE(spi, sysconfig_spi_ids);
> > +
> > +#if IS_ENABLED(CONFIG_OF)
> > +static const struct of_device_id sysconfig_of_ids[] = {
> > +	{
> > +		.compatible = "lattice,ecp5-fpga-mgr",
> > +		.data = ecp5_probe,
> > +	}, {
> > +		.compatible = "lattice,machxo2-fpga-mgr",
> > +		.data = machxo2_probe
> > +	}, {},
> > +};
> > +MODULE_DEVICE_TABLE(of, sysconfig_of_ids);
> > +#endif /* IS_ENABLED(CONFIG_OF) */
> > +
> > +static struct spi_driver lattice_sysconfig_driver = {
> > +	.probe = sysconfig_probe,
> > +	.id_table = sysconfig_spi_ids,
> > +	.driver = {
> > +		.name = "lattice_sysconfig_spi_fpga_mgr",
> > +		.of_match_table = of_match_ptr(sysconfig_of_ids),
> > +	},
> > +};
> > +
> > +module_spi_driver(lattice_sysconfig_driver);
> > +
> > +MODULE_DESCRIPTION("Lattice sysCONFIG Slave SPI FPGA Manager");
> > +MODULE_LICENSE("GPL");
> > -- 
> > 2.37.2
> > 
> > 

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