[v20,1/2] fpga: lattice-sysconfig-spi: add Lattice sysCONFIG FPGA manager

diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
index 6c416955da53..d1a8107fdcb3 100644
--- a/drivers/fpga/Kconfig
+++ b/drivers/fpga/Kconfig
@@ -263,4 +263,15 @@  config FPGA_MGR_MICROCHIP_SPI
 	  programming over slave SPI interface with .dat formatted
 	  bitstream image.
 
+config FPGA_MGR_LATTICE_SYSCONFIG
+	tristate
+
+config FPGA_MGR_LATTICE_SYSCONFIG_SPI
+	tristate "Lattice sysCONFIG SPI FPGA manager"
+	depends on SPI
+	select FPGA_MGR_LATTICE_SYSCONFIG
+	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..72e554b4d2f7 100644
--- a/drivers/fpga/Makefile
+++ b/drivers/fpga/Makefile
@@ -20,6 +20,8 @@  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-$(CONFIG_FPGA_MGR_LATTICE_SYSCONFIG)	+= lattice-sysconfig.o
+obj-$(CONFIG_FPGA_MGR_LATTICE_SYSCONFIG_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..dabad23cbe71
--- /dev/null
+++ b/drivers/fpga/lattice-sysconfig-spi.c
@@ -0,0 +1,153 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Lattice FPGA programming over slave SPI sysCONFIG interface.
+ */
+
+#include <linux/spi/spi.h>
+
+#include "lattice-sysconfig.h"
+
+static const u32 ecp5_spi_max_speed_hz = 60000000;
+
+static int sysconfig_spi_cmd_transfer(struct sysconfig_priv *priv,
+				      const void *tx_buf, size_t tx_len,
+				      void *rx_buf, size_t rx_len)
+{
+	struct spi_device *spi = to_spi_device(priv->dev);
+
+	return spi_write_then_read(spi, tx_buf, tx_len, rx_buf, rx_len);
+}
+
+static int sysconfig_spi_bitstream_burst_init(struct sysconfig_priv *priv)
+{
+	const u8 lsc_bitstream_burst[] = SYSCONFIG_LSC_BITSTREAM_BURST;
+	struct spi_device *spi = to_spi_device(priv->dev);
+	struct spi_transfer xfer = {};
+	struct spi_message msg;
+	size_t buf_len;
+	void *buf;
+	int ret;
+
+	buf_len = sizeof(lsc_bitstream_burst);
+
+	buf = kmemdup(lsc_bitstream_burst, buf_len, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+
+	xfer.len = buf_len;
+	xfer.tx_buf = buf;
+	xfer.cs_change = 1;
+
+	spi_message_init_with_transfers(&msg, &xfer, 1);
+
+	/*
+	 * Lock SPI bus for exclusive usage until FPGA programming is done.
+	 * SPI bus will be released in sysconfig_spi_bitstream_burst_complete().
+	 */
+	spi_bus_lock(spi->controller);
+
+	ret = spi_sync_locked(spi, &msg);
+	if (ret)
+		spi_bus_unlock(spi->controller);
+
+	kfree(buf);
+
+	return ret;
+}
+
+static int sysconfig_spi_bitstream_burst_write(struct sysconfig_priv *priv,
+					       const char *buf, size_t len)
+{
+	struct spi_device *spi = to_spi_device(priv->dev);
+	struct spi_transfer xfer = {
+		.tx_buf = buf,
+		.len = len,
+		.cs_change = 1,
+	};
+	struct spi_message msg;
+
+	spi_message_init_with_transfers(&msg, &xfer, 1);
+
+	return spi_sync_locked(spi, &msg);
+}
+
+static int sysconfig_spi_bitstream_burst_complete(struct sysconfig_priv *priv)
+{
+	struct spi_device *spi = to_spi_device(priv->dev);
+
+	/* Bitstream burst write is done, release SPI bus */
+	spi_bus_unlock(spi->controller);
+
+	/* Toggle CS to finish bitstream write */
+	return spi_write(spi, NULL, 0);
+}
+
+static int sysconfig_spi_probe(struct spi_device *spi)
+{
+	const struct spi_device_id *dev_id;
+	struct device *dev = &spi->dev;
+	struct sysconfig_priv *priv;
+	const u32 *spi_max_speed;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	spi_max_speed = device_get_match_data(dev);
+	if (!spi_max_speed) {
+		dev_id = spi_get_device_id(spi);
+		if (!dev_id)
+			return -ENODEV;
+
+		spi_max_speed = (const u32 *)dev_id->driver_data;
+	}
+
+	if (!spi_max_speed)
+		return -EINVAL;
+
+	if (spi->max_speed_hz > *spi_max_speed) {
+		dev_err(dev, "SPI speed %u is too high, maximum speed is %u\n",
+			spi->max_speed_hz, *spi_max_speed);
+		return -EINVAL;
+	}
+
+	priv->dev = dev;
+	priv->command_transfer = sysconfig_spi_cmd_transfer;
+	priv->bitstream_burst_write_init = sysconfig_spi_bitstream_burst_init;
+	priv->bitstream_burst_write = sysconfig_spi_bitstream_burst_write;
+	priv->bitstream_burst_write_complete = sysconfig_spi_bitstream_burst_complete;
+
+	return sysconfig_probe(priv);
+}
+
+static const struct spi_device_id sysconfig_spi_ids[] = {
+	{
+		.name = "sysconfig-ecp5",
+		.driver_data = (kernel_ulong_t)&ecp5_spi_max_speed_hz,
+	}, {},
+};
+MODULE_DEVICE_TABLE(spi, sysconfig_spi_ids);
+
+#if IS_ENABLED(CONFIG_OF)
+static const struct of_device_id sysconfig_of_ids[] = {
+	{
+		.compatible = "lattice,sysconfig-ecp5",
+		.data = &ecp5_spi_max_speed_hz,
+	}, {},
+};
+MODULE_DEVICE_TABLE(of, sysconfig_of_ids);
+#endif /* IS_ENABLED(CONFIG_OF) */
+
+static struct spi_driver lattice_sysconfig_driver = {
+	.probe = sysconfig_spi_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");
diff --git a/drivers/fpga/lattice-sysconfig.c b/drivers/fpga/lattice-sysconfig.c
new file mode 100644
index 000000000000..ba51a60f672f
--- /dev/null
+++ b/drivers/fpga/lattice-sysconfig.c
@@ -0,0 +1,397 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Lattice FPGA sysCONFIG interface functions independent of port type.
+ */
+
+#include <linux/delay.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/gpio/consumer.h>
+#include <linux/iopoll.h>
+
+#include "lattice-sysconfig.h"
+
+static int sysconfig_cmd_write(struct sysconfig_priv *priv, const void *buf,
+			       size_t buf_len)
+{
+	return priv->command_transfer(priv, buf, buf_len, NULL, 0);
+}
+
+static int sysconfig_cmd_read(struct sysconfig_priv *priv, const void *tx_buf,
+			      size_t tx_len, void *rx_buf, size_t rx_len)
+{
+	return priv->command_transfer(priv, tx_buf, tx_len, rx_buf, rx_len);
+}
+
+static int sysconfig_read_busy(struct sysconfig_priv *priv)
+{
+	const u8 lsc_check_busy[] = SYSCONFIG_LSC_CHECK_BUSY;
+	u8 busy;
+	int ret;
+
+	ret = sysconfig_cmd_read(priv, lsc_check_busy, sizeof(lsc_check_busy),
+				 &busy, sizeof(busy));
+
+	return ret ? : busy;
+}
+
+static int sysconfig_poll_busy(struct sysconfig_priv *priv)
+{
+	int ret, busy;
+
+	ret = read_poll_timeout(sysconfig_read_busy, busy, busy <= 0,
+				SYSCONFIG_POLL_INTERVAL_US,
+				SYSCONFIG_POLL_BUSY_TIMEOUT_US, false, priv);
+
+	return ret ? : busy;
+}
+
+static int sysconfig_read_status(struct sysconfig_priv *priv, u32 *status)
+{
+	const u8 lsc_read_status[] = SYSCONFIG_LSC_READ_STATUS;
+	__be32 device_status;
+	int ret;
+
+	ret = sysconfig_cmd_read(priv, 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 *priv, u32 *status)
+{
+	int ret = sysconfig_poll_busy(priv);
+
+	if (ret)
+		return ret;
+
+	return sysconfig_read_status(priv, status);
+}
+
+static int sysconfig_poll_gpio(struct gpio_desc *gpio, bool is_active)
+{
+	int ret, val;
+
+	ret = read_poll_timeout(gpiod_get_value, val,
+				val < 0 || !!val == is_active,
+				SYSCONFIG_POLL_INTERVAL_US,
+				SYSCONFIG_POLL_GPIO_TIMEOUT_US, false, gpio);
+
+	if (val < 0)
+		return val;
+
+	return ret;
+}
+
+static int sysconfig_gpio_refresh(struct sysconfig_priv *priv)
+{
+	struct gpio_desc *program = priv->program;
+	struct gpio_desc *init = priv->init;
+	struct gpio_desc *done = priv->done;
+	int ret;
+
+	/* Enter init mode */
+	gpiod_set_value(program, 1);
+
+	ret = sysconfig_poll_gpio(init, true);
+	if (!ret)
+		ret = sysconfig_poll_gpio(done, false);
+
+	if (ret)
+		return ret;
+
+	/* Enter program mode */
+	gpiod_set_value(program, 0);
+
+	return sysconfig_poll_gpio(init, false);
+}
+
+static int sysconfig_lsc_refresh(struct sysconfig_priv *priv)
+{
+	static const u8 lsc_refresh[] = SYSCONFIG_LSC_REFRESH;
+	int ret;
+
+	ret = sysconfig_cmd_write(priv, lsc_refresh, sizeof(lsc_refresh));
+	if (ret)
+		return ret;
+
+	usleep_range(4000, 8000);
+
+	return 0;
+}
+
+static int sysconfig_refresh(struct sysconfig_priv *priv)
+{
+	struct gpio_desc *program = priv->program;
+	struct gpio_desc *init = priv->init;
+	struct gpio_desc *done = priv->done;
+
+	if (program && init && done)
+		return sysconfig_gpio_refresh(priv);
+
+	return sysconfig_lsc_refresh(priv);
+}
+
+static int sysconfig_isc_enable(struct sysconfig_priv *priv)
+{
+	u8 isc_enable[] = SYSCONFIG_ISC_ENABLE;
+	u32 status;
+	int ret;
+
+	ret = sysconfig_cmd_write(priv, isc_enable, sizeof(isc_enable));
+	if (ret)
+		return ret;
+
+	ret = sysconfig_poll_status(priv, &status);
+	if (ret)
+		return ret;
+
+	if (status & SYSCONFIG_STATUS_FAIL)
+		return -EFAULT;
+
+	return 0;
+}
+
+static int sysconfig_isc_erase(struct sysconfig_priv *priv)
+{
+	u8 isc_erase[] = SYSCONFIG_ISC_ERASE;
+	u32 status;
+	int ret;
+
+	ret = sysconfig_cmd_write(priv, isc_erase, sizeof(isc_erase));
+	if (ret)
+		return ret;
+
+	ret = sysconfig_poll_status(priv, &status);
+	if (ret)
+		return ret;
+
+	if (status & SYSCONFIG_STATUS_FAIL)
+		return -EFAULT;
+
+	return 0;
+}
+
+static int sysconfig_isc_init(struct sysconfig_priv *priv)
+{
+	int ret = sysconfig_isc_enable(priv);
+
+	if (ret)
+		return ret;
+
+	return sysconfig_isc_erase(priv);
+}
+
+static int sysconfig_lsc_init_addr(struct sysconfig_priv *priv)
+{
+	const u8 lsc_init_addr[] = SYSCONFIG_LSC_INIT_ADDR;
+
+	return sysconfig_cmd_write(priv, lsc_init_addr, sizeof(lsc_init_addr));
+}
+
+static int sysconfig_burst_write_init(struct sysconfig_priv *priv)
+{
+	return priv->bitstream_burst_write_init(priv);
+}
+
+static int sysconfig_burst_write_complete(struct sysconfig_priv *priv)
+{
+	return priv->bitstream_burst_write_complete(priv);
+}
+
+static int sysconfig_bitstream_burst_write(struct sysconfig_priv *priv,
+					   const char *buf, size_t count)
+{
+	int ret = priv->bitstream_burst_write(priv, buf, count);
+
+	if (ret)
+		sysconfig_burst_write_complete(priv);
+
+	return ret;
+}
+
+static int sysconfig_isc_disable(struct sysconfig_priv *priv)
+{
+	const u8 isc_disable[] = SYSCONFIG_ISC_DISABLE;
+
+	return sysconfig_cmd_write(priv, isc_disable, sizeof(isc_disable));
+}
+
+static void sysconfig_cleanup(struct sysconfig_priv *priv)
+{
+	sysconfig_isc_erase(priv);
+	sysconfig_refresh(priv);
+}
+
+static int sysconfig_isc_finish(struct sysconfig_priv *priv)
+{
+	struct gpio_desc *done_gpio = priv->done;
+	u32 status;
+	int ret;
+
+	if (done_gpio) {
+		ret = sysconfig_isc_disable(priv);
+		if (ret)
+			return ret;
+
+		return sysconfig_poll_gpio(done_gpio, true);
+	}
+
+	ret = sysconfig_poll_status(priv, &status);
+	if (ret)
+		return ret;
+
+	if ((status & SYSCONFIG_STATUS_DONE) &&
+	    !(status & SYSCONFIG_STATUS_BUSY) &&
+	    !(status & SYSCONFIG_STATUS_ERR))
+		return sysconfig_isc_disable(priv);
+
+	return -EFAULT;
+}
+
+static enum fpga_mgr_states sysconfig_ops_state(struct fpga_manager *mgr)
+{
+	struct sysconfig_priv *priv = mgr->priv;
+	struct gpio_desc *done = priv->done;
+	u32 status;
+	int ret;
+
+	if (done && (gpiod_get_value(done) > 0))
+		return FPGA_MGR_STATE_OPERATING;
+
+	ret = sysconfig_read_status(priv, &status);
+	if (!ret && (status & SYSCONFIG_STATUS_DONE))
+		return FPGA_MGR_STATE_OPERATING;
+
+	return FPGA_MGR_STATE_UNKNOWN;
+}
+
+static int sysconfig_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 program mode */
+	ret = sysconfig_refresh(priv);
+	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;
+	}
+
+	/* Prepare for bitstream burst write */
+	ret = sysconfig_burst_write_init(priv);
+	if (ret)
+		dev_err(dev, "Failed to prepare for bitstream burst write\n");
+
+	return ret;
+}
+
+static int sysconfig_ops_write(struct fpga_manager *mgr, const char *buf,
+			       size_t count)
+{
+	return sysconfig_bitstream_burst_write(mgr->priv, buf, count);
+}
+
+static int sysconfig_ops_write_complete(struct fpga_manager *mgr,
+					struct fpga_image_info *info)
+{
+	struct sysconfig_priv *priv = mgr->priv;
+	struct device *dev = &mgr->dev;
+	int ret;
+
+	ret = sysconfig_burst_write_complete(priv);
+	if (!ret)
+		ret = sysconfig_poll_busy(priv);
+
+	if (ret) {
+		dev_err(dev, "Error while waiting bitstream write to finish\n");
+		goto fail;
+	}
+
+	ret = sysconfig_isc_finish(priv);
+
+fail:
+	if (ret)
+		sysconfig_cleanup(priv);
+
+	return ret;
+}
+
+static const struct fpga_manager_ops sysconfig_fpga_mgr_ops = {
+	.state = sysconfig_ops_state,
+	.write_init = sysconfig_ops_write_init,
+	.write = sysconfig_ops_write,
+	.write_complete = sysconfig_ops_write_complete,
+};
+
+int sysconfig_probe(struct sysconfig_priv *priv)
+{
+	struct gpio_desc *program, *init, *done;
+	struct device *dev = priv->dev;
+	struct fpga_manager *mgr;
+
+	if (!dev)
+		return -ENODEV;
+
+	if (!priv->command_transfer ||
+	    !priv->bitstream_burst_write_init ||
+	    !priv->bitstream_burst_write ||
+	    !priv->bitstream_burst_write_complete) {
+		dev_err(dev, "Essential callback is missing\n");
+		return -EINVAL;
+	}
+
+	program = devm_gpiod_get_optional(dev, "program", GPIOD_OUT_LOW);
+	if (IS_ERR(program))
+		return dev_err_probe(dev, PTR_ERR(program),
+				     "Failed to get PROGRAM GPIO\n");
+
+	init = devm_gpiod_get_optional(dev, "init", GPIOD_IN);
+	if (IS_ERR(init))
+		return dev_err_probe(dev, PTR_ERR(init),
+				     "Failed to get INIT GPIO\n");
+
+	done = devm_gpiod_get_optional(dev, "done", GPIOD_IN);
+	if (IS_ERR(done))
+		return dev_err_probe(dev, PTR_ERR(done),
+				     "Failed to get DONE GPIO\n");
+
+	priv->program = program;
+	priv->init = init;
+	priv->done = done;
+
+	mgr = devm_fpga_mgr_register(dev, "Lattice sysCONFIG FPGA Manager",
+				     &sysconfig_fpga_mgr_ops, priv);
+
+	return PTR_ERR_OR_ZERO(mgr);
+}
+EXPORT_SYMBOL(sysconfig_probe);
+
+MODULE_DESCRIPTION("Lattice sysCONFIG FPGA Manager Core");
+MODULE_LICENSE("GPL");
diff --git a/drivers/fpga/lattice-sysconfig.h b/drivers/fpga/lattice-sysconfig.h
new file mode 100644
index 000000000000..df47d9a524f6
--- /dev/null
+++ b/drivers/fpga/lattice-sysconfig.h
@@ -0,0 +1,39 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef	__LATTICE_SYSCONFIG_H
+#define	__LATTICE_SYSCONFIG_H
+
+#define	SYSCONFIG_ISC_ENABLE		{0xC6, 0x00, 0x00, 0x00}
+#define	SYSCONFIG_ISC_DISABLE		{0x26, 0x00, 0x00, 0x00}
+#define	SYSCONFIG_ISC_ERASE		{0x0E, 0x01, 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_STATUS_DONE		BIT(8)
+#define	SYSCONFIG_STATUS_BUSY		BIT(12)
+#define	SYSCONFIG_STATUS_FAIL		BIT(13)
+#define	SYSCONFIG_STATUS_ERR		GENMASK(25, 23)
+
+#define	SYSCONFIG_POLL_INTERVAL_US	30
+#define	SYSCONFIG_POLL_BUSY_TIMEOUT_US	1000000
+#define	SYSCONFIG_POLL_GPIO_TIMEOUT_US	100000
+
+struct sysconfig_priv {
+	struct gpio_desc *program;
+	struct gpio_desc *init;
+	struct gpio_desc *done;
+	struct device *dev;
+	int (*command_transfer)(struct sysconfig_priv *priv, const void *tx_buf,
+				size_t tx_len, void *rx_buf, size_t rx_len);
+	int (*bitstream_burst_write_init)(struct sysconfig_priv *priv);
+	int (*bitstream_burst_write)(struct sysconfig_priv *priv,
+				     const char *tx_buf, size_t tx_len);
+	int (*bitstream_burst_write_complete)(struct sysconfig_priv *priv);
+};
+
+int sysconfig_probe(struct sysconfig_priv *priv);
+
+#endif /* __LATTICE_SYSCONFIG_H */