--- /dev/null
+/*
+ * Copyright (C) 2012 Stefan Roese <sr@denx.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/device.h>
+#include <linux/firmware.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/spi/spi.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+
+#define FIRMWARE_NAME "lattice-ecp3.bit"
+
+/*
+ * The JTAG ID's of the supported FPGA's. The ID is 32bit wide
+ * reversed as noted in the manual.
+ */
+#define ID_ECP3_17 0xc2088080
+#define ID_ECP3_35 0xc2048080
+
+/* FPGA commands */
+#define FPGA_CMD_READ_ID 0x07 /* plus 24 bits */
+#define FPGA_CMD_READ_STATUS 0x09 /* plus 24 bits */
+#define FPGA_CMD_CLEAR 0x70
+#define FPGA_CMD_REFRESH 0x71
+#define FPGA_CMD_WRITE_EN 0x4a /* plus 2 bits */
+#define FPGA_CMD_WRITE_DIS 0x4f /* plus 8 bits */
+#define FPGA_CMD_WRITE_INC 0x41 /* plus 0 bits */
+
+/*
+ * The status register is 32bit revered, DONE is bit 17 from the TN1222.pdf
+ * (LatticeECP3 Slave SPI Port User's Guide)
+ */
+#define FPGA_STATUS_DONE 0x00004000
+#define FPGA_STATUS_CLEARED 0x00010000
+
+#define FPGA_CLEAR_TIMEOUT 5000 /* max. 5000ms for FPGA clear */
+#define FPGA_CLEAR_MSLEEP 10
+#define FPGA_CLEAR_LOOP_COUNT (FPGA_CLEAR_TIMEOUT / FPGA_CLEAR_MSLEEP)
+
+struct fpga_data {
+ struct completion fw_loaded;
+};
+
+struct ecp3_dev {
+ u32 jedec_id;
+ char *name;
+};
+
+static const struct ecp3_dev ecp3_dev[] = {
+ {
+ .jedec_id = ID_ECP3_17,
+ .name = "Lattice ECP3-17",
+ },
+ {
+ .jedec_id = ID_ECP3_35,
+ .name = "Lattice ECP3-35",
+ },
+};
+
+static void firmware_load(const struct firmware *fw, void *context)
+{
+ struct spi_device *spi = (struct spi_device *)context;
+ struct fpga_data *data = dev_get_drvdata(&spi->dev);
+ u8 *buffer;
+ int ret;
+ u8 txbuf[8];
+ u8 rxbuf[8];
+ int rx_len = 8;
+ int i;
+ u32 jedec_id;
+ u32 status;
+
+ if (fw->size == 0) {
+ dev_err(&spi->dev, "Error: Firmware size is 0!\n");
+ return;
+ }
+
+ /* Fill dummy data (24 stuffing bits for commands) */
+ txbuf[1] = 0x00;
+ txbuf[2] = 0x00;
+ txbuf[3] = 0x00;
+
+ /* Trying to speak with the FPGA via SPI... */
+ txbuf[0] = FPGA_CMD_READ_ID;
+ ret = spi_write_then_read(spi, txbuf, 8, rxbuf, rx_len);
+ dev_dbg(&spi->dev, "FPGA JTAG ID=%08x\n", *(u32 *)&rxbuf[4]);
+ jedec_id = *(u32 *)&rxbuf[4];
+
+ for (i = 0; i < ARRAY_SIZE(ecp3_dev); i++) {
+ if (jedec_id == ecp3_dev[i].jedec_id)
+ break;
+ }
+ if (i == ARRAY_SIZE(ecp3_dev)) {
+ dev_err(&spi->dev,
+ "Error: No supported FPGA detected (JEDEC_ID=%08x)!\n",
+ jedec_id);
+ return;
+ }
+
+ dev_info(&spi->dev, "FPGA %s detected\n", ecp3_dev[i].name);
+
+ txbuf[0] = FPGA_CMD_READ_STATUS;
+ ret = spi_write_then_read(spi, txbuf, 8, rxbuf, rx_len);
+ dev_dbg(&spi->dev, "FPGA Status=%08x\n", *(u32 *)&rxbuf[4]);
+
+ buffer = kzalloc(fw->size + 8, GFP_KERNEL);
+ if (!buffer) {
+ dev_err(&spi->dev, "Error: Can't allocate memory!\n");
+ return;
+ }
+
+ /*
+ * Insert WRITE_INC command into stream (one SPI frame)
+ */
+ buffer[0] = FPGA_CMD_WRITE_INC;
+ buffer[1] = 0xff;
+ buffer[2] = 0xff;
+ buffer[3] = 0xff;
+ memcpy(buffer + 4, fw->data, fw->size);
+
+ txbuf[0] = FPGA_CMD_REFRESH;
+ ret = spi_write(spi, txbuf, 4);
+
+ txbuf[0] = FPGA_CMD_WRITE_EN;
+ ret = spi_write(spi, txbuf, 4);
+
+ txbuf[0] = FPGA_CMD_CLEAR;
+ ret = spi_write(spi, txbuf, 4);
+
+ /*
+ * Wait for FPGA memory to become cleared
+ */
+ for (i = 0; i < FPGA_CLEAR_LOOP_COUNT; i++) {
+ txbuf[0] = FPGA_CMD_READ_STATUS;
+ ret = spi_write_then_read(spi, txbuf, 8, rxbuf, rx_len);
+ status = *(u32 *)&rxbuf[4];
+ if (status == FPGA_STATUS_CLEARED)
+ break;
+
+ msleep(FPGA_CLEAR_MSLEEP);
+ }
+
+ if (i == FPGA_CLEAR_LOOP_COUNT) {
+ dev_err(&spi->dev,
+ "Error: Timeout waiting for FPGA to clear (status=%08x)!\n",
+ status);
+ kfree(buffer);
+ return;
+ }
+
+ dev_info(&spi->dev, "Configuring the FPGA...\n");
+ ret = spi_write(spi, buffer, fw->size + 8);
+
+ txbuf[0] = FPGA_CMD_WRITE_DIS;
+ ret = spi_write(spi, txbuf, 4);
+
+ txbuf[0] = FPGA_CMD_READ_STATUS;
+ ret = spi_write_then_read(spi, txbuf, 8, rxbuf, rx_len);
+ dev_dbg(&spi->dev, "FPGA Status=%08x\n", *(u32 *)&rxbuf[4]);
+ status = *(u32 *)&rxbuf[4];
+
+ /* Check result */
+ if (status & FPGA_STATUS_DONE)
+ dev_info(&spi->dev, "FPGA succesfully configured!\n");
+ else
+ dev_info(&spi->dev, "FPGA not configured (DONE not set)\n");
+
+ /*
+ * Don't forget to release the firmware again
+ */
+ release_firmware(fw);
+
+ kfree(buffer);
+
+ complete(&data->fw_loaded);
+}
+
+static int __devinit lattice_ecp3_probe(struct spi_device *spi)
+{
+ struct fpga_data *data;
+ int err;
+
+ data = devm_kzalloc(&spi->dev, sizeof(*data), GFP_KERNEL);
+ if (!data) {
+ dev_err(&spi->dev, "Memory allocation for fpga_data failed\n");
+ return -ENOMEM;
+ }
+ spi_set_drvdata(spi, data);
+
+ init_completion(&data->fw_loaded);
+ err = request_firmware_nowait(THIS_MODULE, FW_ACTION_NOHOTPLUG,
+ FIRMWARE_NAME, &spi->dev,
+ GFP_KERNEL, spi, firmware_load);
+ if (err) {
+ dev_err(&spi->dev, "Firmware loading failed with %d!\n", err);
+ return err;
+ }
+
+ dev_info(&spi->dev, "FPGA bitstream configuration driver registered\n");
+
+ return 0;
+}
+
+static int __devexit lattice_ecp3_remove(struct spi_device *spi)
+{
+ struct fpga_data *data = spi_get_drvdata(spi);
+
+ wait_for_completion(&data->fw_loaded);
+
+ return 0;
+}
+
+static const struct spi_device_id lattice_ecp3_id[] __devinitdata = {
+ { "ecp3-17", 0 },
+ { "ecp3-35", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(spi, lattice_ecp3_id);
+
+static struct spi_driver lattice_ecp3_driver = {
+ .driver = {
+ .name = "lattice-ecp3",
+ .owner = THIS_MODULE,
+ },
+ .probe = lattice_ecp3_probe,
+ .remove = __devexit_p(lattice_ecp3_remove),
+ .id_table = lattice_ecp3_id,
+};
+
+module_spi_driver(lattice_ecp3_driver);
+
+MODULE_AUTHOR("Stefan Roese <sr@denx.de>");
+MODULE_DESCRIPTION("Lattice ECP3 FPGA configuration via SPI");
+MODULE_LICENSE("GPL");
projects / platform / kernel / linux-stable.git / commitdiff