Add support to the FPGA manager for programming Lattice ECP5 FPGA over
slave SPI interface with .bit formatted uncompressed bitstream image.
Signed-off-by: Ivan Bornyakov <i.bornyakov@xxxxxxxxxxx>
---
drivers/fpga/Kconfig | 7 +
drivers/fpga/Makefile | 1 +
drivers/fpga/ecp5-spi.c | 275 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 283 insertions(+)
create mode 100644 drivers/fpga/ecp5-spi.c
diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
index 6c416955da53..920277a08ed9 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_ECP5_SPI
+ tristate "Lattice ECP5 SPI FPGA manager"
+ depends on SPI
+ help
+ FPGA manager driver support for Lattice ECP5 programming over slave
+ SPI interface with .bit formatted uncompressed bitstream image.
+
endif # FPGA
diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
index 42ae8b58abce..17c7a3c4b385 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-$(CONFIG_FPGA_MGR_ECP5_SPI) += ecp5-spi.o
obj-$(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/ecp5-spi.c b/drivers/fpga/ecp5-spi.c
new file mode 100644
index 000000000000..7293f19931e0
--- /dev/null
+++ b/drivers/fpga/ecp5-spi.c
@@ -0,0 +1,275 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Lattice ECP5 FPGA programming over slave SPI interface.
+ */
+
+#include <linux/delay.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/spi/spi.h>
+
+#define ECP5_SPI_MAX_SPEED_HZ 60000000
+
+#define ECP5_SPI_ISC_ENABLE {0xC6, 0x00, 0x00, 0x00}
+#define ECP5_SPI_ISC_DISABLE {0x26, 0x00, 0x00, 0x00}
+#define ECP5_SPI_ISC_ERASE {0x0E, 0x01, 0x00, 0x00}
+#define ECP5_SPI_LSC_INIT_ADDR {0x46, 0x00, 0x00, 0x00}
+#define ECP5_SPI_LSC_BITSTREAM_BURST {0x7a, 0x00, 0x00, 0x00}
+#define ECP5_SPI_LSC_CHECK_BUSY {0xF0, 0x00, 0x00, 0x00}
+
+#define ECP5_POLL_RETRIES 100000
+
+struct ecp5_priv {
+ struct gpio_desc *program;
+ struct gpio_desc *init;
+ struct gpio_desc *done;
+ struct spi_device *spi;
+};
+
+static enum fpga_mgr_states ecp5_ops_state(struct fpga_manager *mgr)
+{
+ struct ecp5_priv *priv = mgr->priv;
+
+ return gpiod_get_value(priv->done) ? FPGA_MGR_STATE_OPERATING :
+ FPGA_MGR_STATE_UNKNOWN;
+}
+
+static int ecp5_poll_busy(struct spi_device *spi)
+{
+ const u8 lsc_check_busy[] = ECP5_SPI_LSC_CHECK_BUSY;
+ int ret, retries = ECP5_POLL_RETRIES;
+ struct spi_transfer xfers[2] = { 0 };
+ u8 busy;
+
+ xfers[0].tx_buf = lsc_check_busy;
+ xfers[0].len = sizeof(lsc_check_busy);
+ xfers[1].rx_buf = &busy;
+ xfers[1].len = sizeof(busy);
+
+ while (retries--) {
+ ret = spi_sync_transfer(spi, xfers, ARRAY_SIZE(xfers));
+ if (ret)
+ return ret;
+
+ if (!busy)
+ return 0;
+
+ usleep_range(50, 100);
+ }
+
+ return -EBUSY;
+}
+
+static int ecp5_poll_gpio(struct gpio_desc *gpio, bool is_active)
+{
+ int value, retries = ECP5_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 -EFAULT;
+}
+
+static int ecp5_ops_write_init(struct fpga_manager *mgr,
+ struct fpga_image_info *info,
+ const char *buf, size_t count)
+{
+ const u8 lsc_bitstream_burst[] = ECP5_SPI_LSC_BITSTREAM_BURST;
+ const u8 lsc_init_addr[] = ECP5_SPI_LSC_INIT_ADDR;
+ const u8 isc_enable[] = ECP5_SPI_ISC_ENABLE;
+ const u8 isc_erase[] = ECP5_SPI_ISC_ERASE;
+ struct ecp5_priv *priv = mgr->priv;
+ struct spi_device *spi = priv->spi;
+ struct device *dev = &mgr->dev;
+ struct spi_transfer isc_xfers[] = {
+ {
+ .tx_buf = isc_enable,
+ .len = sizeof(isc_enable),
+ .cs_change = 1,
+ }, {
+ .tx_buf = isc_erase,
+ .len = sizeof(isc_erase),
+ },
+ };
+ struct spi_transfer lsc_xfers[] = {
+ {
+ .tx_buf = lsc_init_addr,
+ .len = sizeof(lsc_init_addr),
+ .cs_change = 1,
+ }, {
+ .tx_buf = lsc_bitstream_burst,
+ .len = sizeof(lsc_bitstream_burst),
+ .cs_change = 1,
+ },
+ };
+ int ret;
+
+ if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) {
+ dev_err(dev, "Partial reconfiguration is not supported\n");
+ return -EOPNOTSUPP;
+ }
+
+ /* Enter init mode */
+ gpiod_set_value(priv->program, 1);
+
+ ret = ecp5_poll_gpio(priv->init, true);
+ if (!ret)
+ ret = ecp5_poll_gpio(priv->done, false);
+
+ if (ret) {
+ dev_err(dev, "Failed to go to initialization mode\n");
+ return ret;
+ }
+
+ /* Enter program mode */
+ gpiod_set_value(priv->program, 0);
+
+ ret = ecp5_poll_gpio(priv->init, false);
+ if (ret) {
+ dev_err(dev, "Failed to go to program mode\n");
+ return ret;
+ }
+
+ /* Enter ISC mode */
+ ret = spi_sync_transfer(spi, isc_xfers, ARRAY_SIZE(isc_xfers));
+ if (!ret)
+ ret = ecp5_poll_busy(spi);
+
+ if (ret) {
+ dev_err(dev, "Failed to go to ISC mode\n");
+ return ret;
+ }
+
+ /* Prepare for bitstream burst write */
+ return spi_sync_transfer(spi, lsc_xfers, ARRAY_SIZE(lsc_xfers));
+}
+
+static int ecp5_ops_write(struct fpga_manager *mgr, const char *buf, size_t count)
+{
+ struct ecp5_priv *priv = mgr->priv;
+ struct spi_transfer xfer = {
+ .tx_buf = buf,
+ .len = count,
+ .cs_change = 1,
+ };
+
+ return spi_sync_transfer(priv->spi, &xfer, 1);
+}
+
+static int ecp5_ops_write_complete(struct fpga_manager *mgr,
+ struct fpga_image_info *info)
+{
+ const u8 isc_disable[] = ECP5_SPI_ISC_DISABLE;
+ struct ecp5_priv *priv = mgr->priv;
+ struct spi_device *spi = priv->spi;
+ struct device *dev = &mgr->dev;
+ int ret;
+
+ /* Toggle CS and wait for bitstream write to finish */
+ ret = spi_write(spi, NULL, 0);
+ if (!ret)
+ ret = ecp5_poll_busy(spi);
+
+ if (ret) {
+ dev_err(dev, "Error while waiting bitstream write to finish\n");
+ return ret;
+ }
+
+ /* Exit ISC mode */
+ ret = spi_write(spi, isc_disable, sizeof(isc_disable));
+ if (!ret)
+ ret = ecp5_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 spi_device *spi)
+{
+ struct device *dev = &spi->dev;
+ struct fpga_manager *mgr;
+ struct ecp5_priv *priv;
+ 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 = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->spi = spi;
+
+ 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 const struct spi_device_id ecp5_spi_ids[] = {
+ { .name = "ecp5-fpga-mgr" },
+ {},
+};
+MODULE_DEVICE_TABLE(spi, ecp5_spi_ids);
+
+#if IS_ENABLED(CONFIG_OF)
+static const struct of_device_id ecp5_of_ids[] = {
+ { .compatible = "lattice,ecp5-fpga-mgr" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, ecp5_of_ids);
+#endif /* IS_ENABLED(CONFIG_OF) */
+
+static struct spi_driver ecp5_driver = {
+ .probe = ecp5_probe,
+ .id_table = ecp5_spi_ids,
+ .driver = {
+ .name = "lattice_ecp5_spi_fpga_mgr",
+ .of_match_table = of_match_ptr(ecp5_of_ids),
+ },
+};
+
+module_spi_driver(ecp5_driver);
+
+MODULE_DESCRIPTION("Lattice ECP5 SPI FPGA Manager");
+MODULE_LICENSE("GPL");
--
2.37.1
