diff options
Diffstat (limited to 'drivers/misc/lattice-ecp3-config.c')
| -rw-r--r-- | drivers/misc/lattice-ecp3-config.c | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/drivers/misc/lattice-ecp3-config.c b/drivers/misc/lattice-ecp3-config.c new file mode 100644 index 0000000..155700b --- /dev/null +++ b/drivers/misc/lattice-ecp3-config.c @@ -0,0 +1,243 @@ +/* + * 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 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 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[] = { + { "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 = 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"); |
