This patch adds support to the FPGA manager for programming
MachXO2 device’s internal flash memory, via slave SPI.
Signed-off-by: Paolo Pisati <p.pisati@xxxxxxxxx>
---
drivers/fpga/Kconfig | 7 +
drivers/fpga/Makefile | 1 +
drivers/fpga/machxo2-spi.c | 405 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 413 insertions(+)
create mode 100644 drivers/fpga/machxo2-spi.c
diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
index f47ef84..53d3f55 100644
--- a/drivers/fpga/Kconfig
+++ b/drivers/fpga/Kconfig
@@ -70,6 +70,13 @@ config FPGA_MGR_ICE40_SPI
help
FPGA manager driver support for Lattice iCE40 FPGAs over SPI.
+config FPGA_MGR_MACHXO2_SPI
+ tristate "Lattice MachXO2 SPI"
+ depends on SPI
+ help
+ FPGA manager driver support for Lattice MachXO2 configuration
+ over slave SPI interface.
+
config FPGA_MGR_TS73XX
tristate "Technologic Systems TS-73xx SBC FPGA Manager"
depends on ARCH_EP93XX && MACH_TS72XX
diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
index 3cb276a..f9803da 100644
--- a/drivers/fpga/Makefile
+++ b/drivers/fpga/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_FPGA) += fpga-mgr.o
obj-$(CONFIG_FPGA_MGR_ALTERA_CVP) += altera-cvp.o
obj-$(CONFIG_FPGA_MGR_ALTERA_PS_SPI) += altera-ps-spi.o
obj-$(CONFIG_FPGA_MGR_ICE40_SPI) += ice40-spi.o
+obj-$(CONFIG_FPGA_MGR_MACHXO2_SPI) += machxo2-spi.o
obj-$(CONFIG_FPGA_MGR_SOCFPGA) += socfpga.o
obj-$(CONFIG_FPGA_MGR_SOCFPGA_A10) += socfpga-a10.o
obj-$(CONFIG_FPGA_MGR_TS73XX) += ts73xx-fpga.o
diff --git a/drivers/fpga/machxo2-spi.c b/drivers/fpga/machxo2-spi.c
new file mode 100644
index 0000000..783aaf2
--- /dev/null
+++ b/drivers/fpga/machxo2-spi.c
@@ -0,0 +1,405 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Lattice MachXO2 Slave SPI Driver
+ *
+ * Manage Lattice FPGA firmware that is loaded over SPI using
+ * the slave serial configuration interface.
+ *
+ * Copyright (C) 2018 Paolo Pisati <p.pisati@xxxxxxxxx>
+ */
+
+#include <linux/delay.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/spi/spi.h>
+
+/* MachXO2 Programming Guide - sysCONFIG Programming Commands */
+#define IDCODE_PUB {0xe0, 0x00, 0x00, 0x00}
+#define ISC_ENABLE {0xc6, 0x08, 0x00, 0x00}
+#define ISC_ERASE {0x0e, 0x04, 0x00, 0x00}
+#define ISC_PROGRAMDONE {0x5e, 0x00, 0x00, 0x00}
+#define LSC_INITADDRESS {0x46, 0x00, 0x00, 0x00}
+#define LSC_PROGINCRNV {0x70, 0x00, 0x00, 0x01}
+#define LSC_READ_STATUS {0x3c, 0x00, 0x00, 0x00}
+#define LSC_REFRESH {0x79, 0x00, 0x00, 0x00}
+
+/*
+ * Max CCLK in Slave SPI mode according to 'MachXO2 Family Data
+ * Sheet' sysCONFIG Port Timing Specifications (3-36)
+ */
+#define MACHXO2_MAX_SPEED 66000000
+
+#define MACHXO2_LOW_DELAY_USEC 5
+#define MACHXO2_HIGH_DELAY_USEC 200
+#define MACHXO2_REFRESH_USEC 4800
+#define MACHXO2_MAX_BUSY_LOOP 128
+#define MACHXO2_MAX_REFRESH_LOOP 16
+
+#define MACHXO2_PAGE_SIZE 16
+#define MACHXO2_BUF_SIZE (MACHXO2_PAGE_SIZE + 4)
+
+/* Status register bits, errors and error mask */
+#define BUSY 12
+#define DONE 8
+#define DVER 27
+#define ENAB 9
+#define ERRBITS 23
+#define ERRMASK 7
+#define FAIL 13
+
+#define ENOERR 0 /* no error */
+#define EID 1
+#define ECMD 2
+#define ECRC 3
+#define EPREAM 4 /* preamble error */
+#define EABRT 5 /* abort error */
+#define EOVERFL 6 /* overflow error */
+#define ESDMEOF 7 /* SDM EOF */
+
+static inline u8 get_err(unsigned long *status)
+{
+ return (*status >> ERRBITS) & ERRMASK;
+}
+
+static int get_status(struct spi_device *spi, unsigned long *status)
+{
+ struct spi_message msg;
+ struct spi_transfer rx, tx;
+ static const u8 cmd[] = LSC_READ_STATUS;
+ int ret;
+
+ memset(&rx, 0, sizeof(rx));
+ memset(&tx, 0, sizeof(tx));
+ tx.tx_buf = cmd;
+ tx.len = sizeof(cmd);
+ rx.rx_buf = status;
+ rx.len = 4;
+ spi_message_init(&msg);
+ spi_message_add_tail(&tx, &msg);
+ spi_message_add_tail(&rx, &msg);
+ ret = spi_sync(spi, &msg);
+ if (ret)
+ return ret;
+
+ *status = be32_to_cpu(*status);
+
+ return 0;
+}
+
+#ifdef DEBUG
+static const char *get_err_string(u8 err)
+{
+ switch (err) {
+ case ENOERR: return "No Error";
+ case EID: return "ID ERR";
+ case ECMD: return "CMD ERR";
+ case ECRC: return "CRC ERR";
+ case EPREAM: return "Preamble ERR";
+ case EABRT: return "Abort ERR";
+ case EOVERFL: return "Overflow ERR";
+ case ESDMEOF: return "SDM EOF";
+ }
+
+ return "Default switch case";
+}
+#endif
+
+static void dump_status_reg(unsigned long *status)
+{
+#ifdef DEBUG
+ pr_debug("machxo2 status: 0x%08lX - done=%d, cfgena=%d, busy=%d, fail=%d, devver=%d, err=%s\n",
+ *status, test_bit(DONE, status), test_bit(ENAB, status),
+ test_bit(BUSY, status), test_bit(FAIL, status),
+ test_bit(DVER, status), get_err_string(get_err(status)));
+#endif
+}
+
+static int wait_until_not_busy(struct spi_device *spi)
+{
+ unsigned long status;
+ int ret, loop = 0;
+
+ do {
+ ret = get_status(spi, &status);
+ if (ret)
+ return ret;
+ if (++loop >= MACHXO2_MAX_BUSY_LOOP)
+ return -EBUSY;
+ } while (test_bit(BUSY, &status));
+
+ return 0;
+}
+
+static int machxo2_cleanup(struct fpga_manager *mgr)
+{
+ struct spi_device *spi = mgr->priv;
+ struct spi_message msg;
+ struct spi_transfer tx[2];
+ static const u8 erase[] = ISC_ERASE;
+ static const u8 refresh[] = LSC_REFRESH;
+ int ret;
+
+ memset(tx, 0, sizeof(tx));
+ spi_message_init(&msg);
+ tx[0].tx_buf = &erase;
+ tx[0].len = sizeof(erase);
+ spi_message_add_tail(&tx[0], &msg);
+ ret = spi_sync(spi, &msg);
+ if (ret)
+ goto fail;
+
+ ret = wait_until_not_busy(spi);
+ if (ret)
+ goto fail;
+
+ spi_message_init(&msg);
+ tx[1].tx_buf = &refresh;
+ tx[1].len = sizeof(refresh);
+ tx[1].delay_usecs = MACHXO2_REFRESH_USEC;
+ spi_message_add_tail(&tx[1], &msg);
+ ret = spi_sync(spi, &msg);
+ if (ret)
+ goto fail;
+
+ return 0;
+fail:
+ dev_err(&mgr->dev, "Cleanup failed\n");
+
+ return ret;
+}
+
+static enum fpga_mgr_states machxo2_spi_state(struct fpga_manager *mgr)
+{
+ return FPGA_MGR_STATE_UNKNOWN;
+}
+
+static int machxo2_write_init(struct fpga_manager *mgr,
+ struct fpga_image_info *info,
+ const char *buf, size_t count)
+{
+ struct spi_device *spi = mgr->priv;
+ struct spi_message msg;
+ struct spi_transfer tx[3];
+ static const u8 enable[] = ISC_ENABLE;
+ static const u8 erase[] = ISC_ERASE;
+ static const u8 initaddr[] = LSC_INITADDRESS;
+ unsigned long status;
+ int ret;
+
+ if ((info->flags & FPGA_MGR_PARTIAL_RECONFIG)) {
+ dev_err(&mgr->dev,
+ "Partial reconfiguration is not supported\n");
+ return -ENOTSUPP;
+ }
+
+ get_status(spi, &status);
+ dump_status_reg(&status);
+ memset(tx, 0, sizeof(tx));
+ spi_message_init(&msg);
+ tx[0].tx_buf = &enable;
+ tx[0].len = sizeof(enable);
+ tx[0].delay_usecs = MACHXO2_LOW_DELAY_USEC;
+ spi_message_add_tail(&tx[0], &msg);
+
+ tx[1].tx_buf = &erase;
+ tx[1].len = sizeof(erase);
+ spi_message_add_tail(&tx[1], &msg);
+ ret = spi_sync(spi, &msg);
+ if (ret)
+ goto fail;
+
+ ret = wait_until_not_busy(spi);
+ if (ret)
+ goto fail;
+
+ get_status(spi, &status);
+ if (test_bit(FAIL, &status))
+ goto fail;
+ dump_status_reg(&status);
+
+ spi_message_init(&msg);
+ tx[2].tx_buf = &initaddr;
+ tx[2].len = sizeof(initaddr);
+ spi_message_add_tail(&tx[2], &msg);
+ ret = spi_sync(spi, &msg);
+ if (ret)
+ goto fail;
+
+ get_status(spi, &status);
+ dump_status_reg(&status);
+
+ return 0;
+fail:
+ dev_err(&mgr->dev, "Error during FPGA init.\n");
+
+ return ret;
+}
+
+static int machxo2_write(struct fpga_manager *mgr, const char *buf,
+ size_t count)
+{
+ struct spi_device *spi = mgr->priv;
+ struct spi_message msg;
+ struct spi_transfer tx;
+ static const u8 progincr[] = LSC_PROGINCRNV;
+ u8 payload[MACHXO2_BUF_SIZE];
+ unsigned long status;
+ int i, ret;
+
+ if (count % MACHXO2_PAGE_SIZE != 0) {
+ dev_err(&mgr->dev, "Malformed payload.\n");
+ return -EINVAL;
+ }
+ get_status(spi, &status);
+ dump_status_reg(&status);
+ memcpy(payload, &progincr, sizeof(progincr));
+ for (i = 0; i < count; i += MACHXO2_PAGE_SIZE) {
+ memcpy(&payload[sizeof(progincr)], &buf[i], MACHXO2_PAGE_SIZE);
+ memset(&tx, 0, sizeof(tx));
+ spi_message_init(&msg);
+ tx.tx_buf = payload;
+ tx.len = MACHXO2_BUF_SIZE;
+ tx.delay_usecs = MACHXO2_HIGH_DELAY_USEC;
+ spi_message_add_tail(&tx, &msg);
+ ret = spi_sync(spi, &msg);
+ if (ret) {
+ dev_err(&mgr->dev, "Error loading the bitstream.\n");
+ return ret;
+ }
+ }
+ get_status(spi, &status);
+ dump_status_reg(&status);
+
+ return 0;
+}
+
+static int machxo2_write_complete(struct fpga_manager *mgr,
+ struct fpga_image_info *info)
+{
+ struct spi_device *spi = mgr->priv;
+ struct spi_message msg;
+ struct spi_transfer tx[2];
+ static const u8 progdone[] = ISC_PROGRAMDONE;
+ static const u8 refresh[] = LSC_REFRESH;
+ unsigned long status;
+ int ret, refreshloop = 0;
+
+ memset(tx, 0, sizeof(tx));
+ spi_message_init(&msg);
+ tx[0].tx_buf = &progdone;
+ tx[0].len = sizeof(progdone);
+ spi_message_add_tail(&tx[0], &msg);
+ ret = spi_sync(spi, &msg);
+ if (ret)
+ goto fail;
+ ret = wait_until_not_busy(spi);
+ if (ret)
+ goto fail;
+
+ get_status(spi, &status);
+ dump_status_reg(&status);
+ if (!test_bit(DONE, &status)) {
+ machxo2_cleanup(mgr);
+ goto fail;
+ }
+
+ do {
+ spi_message_init(&msg);
+ tx[1].tx_buf = &refresh;
+ tx[1].len = sizeof(refresh);
+ tx[1].delay_usecs = MACHXO2_REFRESH_USEC;
+ spi_message_add_tail(&tx[1], &msg);
+ ret = spi_sync(spi, &msg);
+ if (ret)
+ goto fail;
+
+ /* check refresh status */
+ get_status(spi, &status);
+ dump_status_reg(&status);
+ if (!test_bit(BUSY, &status) && test_bit(DONE, &status) &&
+ get_err(&status) == ENOERR)
+ break;
+ if (++refreshloop == MACHXO2_MAX_REFRESH_LOOP) {
+ machxo2_cleanup(mgr);
+ goto fail;
+ }
+ } while (1);
+
+ get_status(spi, &status);
+ dump_status_reg(&status);
+
+ return 0;
+fail:
+ dev_err(&mgr->dev, "Refresh failed.\n");
+
+ return ret;
+}
+
+static const struct fpga_manager_ops machxo2_ops = {
+ .state = machxo2_spi_state,
+ .write_init = machxo2_write_init,
+ .write = machxo2_write,
+ .write_complete = machxo2_write_complete,
+};
+
+static int machxo2_spi_probe(struct spi_device *spi)
+{
+ struct device *dev = &spi->dev;
+ struct fpga_manager *mgr;
+
+ if (spi->max_speed_hz > MACHXO2_MAX_SPEED) {
+ dev_err(dev, "Speed is too high\n");
+ return -EINVAL;
+ }
+
+ mgr = devm_kzalloc(dev, sizeof(*mgr), GFP_KERNEL);
+ if (!mgr)
+ return -ENOMEM;
+
+ mgr->parent = dev;
+ mgr->name = "Lattice MachXO2 SPI FPGA Manager";
+ mgr->mops = &machxo2_ops;
+ mgr->priv = spi;
+ spi_set_drvdata(spi, mgr);
+
+ return fpga_mgr_register(mgr);
+}
+
+static int machxo2_spi_remove(struct spi_device *spi)
+{
+ struct fpga_manager *mgr = spi_get_drvdata(spi);
+
+ fpga_mgr_unregister(mgr);
+
+ return 0;
+}
+
+static const struct of_device_id of_match[] = {
+ { .compatible = "lattice,machxo2-slave-spi", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, of_match);
+
+static const struct spi_device_id lattice_ids[] = {
+ { "machxo2-slave-spi", 0 },
+ { },
+};
+MODULE_DEVICE_TABLE(spi, lattice_ids);
+
+static struct spi_driver machxo2_spi_driver = {
+ .driver = {
+ .name = "machxo2-slave-spi",
+ .of_match_table = of_match_ptr(of_match),
+ },
+ .probe = machxo2_spi_probe,
+ .remove = machxo2_spi_remove,
+ .id_table = lattice_ids,
+};
+
+module_spi_driver(machxo2_spi_driver)
+
+MODULE_AUTHOR("Paolo Pisati <p.pisati@xxxxxxxxx>");
+MODULE_DESCRIPTION("Load Lattice FPGA firmware over SPI");
+MODULE_LICENSE("GPL v2");
--
2.7.4
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