blob: 4668e7f2506852bb886ec10d7b7ac93d18e6700a [file] [log] [blame]
/*
* This file is part of the flashrom project.
*
* Copyright (C) 2011 Sven Schnelle <svens@stackframe.org>
*
* 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; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#if CONFIG_LINUX_SPI == 1
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdint.h>
#include <inttypes.h>
#include <fcntl.h>
#include <errno.h>
#include <ctype.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <linux/types.h>
#include "flash.h"
#include "chipdrivers.h"
#include "programmer.h"
#include "spi.h"
/*
* Linux versions prior to v4.14-rc7 may need linux/ioctl.h included here due
* to missing from linux/spi/spidev.h. This was fixed in the following commit:
* a2b4a79b88b2 spi: uapi: spidev: add missing ioctl header
*/
#include <linux/ioctl.h>
#include <linux/spi/spidev.h>
/* Devices known to work with this module (FIXME: export as struct dev_entry):
* Beagle Bone Black
* Raspberry Pi
* HummingBoard
*/
#define BUF_SIZE_FROM_SYSFS "/sys/module/spidev/parameters/bufsiz"
struct linux_spi_data {
int fd;
size_t max_kernel_buf_size;
};
static int linux_spi_read(struct flashctx *flash, uint8_t *buf, unsigned int start, unsigned int len)
{
struct linux_spi_data *spi_data = flash->mst->spi.data;
/* Older kernels use a single buffer for combined input and output
data. So account for longest possible command + address, too. */
return spi_read_chunked(flash, buf, start, len, spi_data->max_kernel_buf_size - 5);
}
static int linux_spi_write_256(struct flashctx *flash, const uint8_t *buf, unsigned int start, unsigned int len)
{
struct linux_spi_data *spi_data = flash->mst->spi.data;
/* 5 bytes must be reserved for longest possible command + address. */
return spi_write_chunked(flash, buf, start, len, spi_data->max_kernel_buf_size - 5);
}
static int linux_spi_shutdown(void *data)
{
struct linux_spi_data *spi_data = data;
close(spi_data->fd);
free(spi_data);
return 0;
}
static int linux_spi_send_command(const struct flashctx *flash, unsigned int writecnt,
unsigned int readcnt,
const unsigned char *txbuf,
unsigned char *rxbuf)
{
struct linux_spi_data *spi_data = flash->mst->spi.data;
int iocontrol_code;
struct spi_ioc_transfer msg[2] = {
{
.tx_buf = (uint64_t)(uintptr_t)txbuf,
.len = writecnt,
},
{
.rx_buf = (uint64_t)(uintptr_t)rxbuf,
.len = readcnt,
},
};
if (spi_data->fd == -1)
return -1;
/* The implementation currently does not support requests that
don't start with sending a command. */
if (writecnt == 0)
return SPI_INVALID_LENGTH;
/* Just submit the first (write) request in case there is nothing
to read. Otherwise submit both requests. */
if (readcnt == 0)
iocontrol_code = SPI_IOC_MESSAGE(1);
else
iocontrol_code = SPI_IOC_MESSAGE(2);
if (ioctl(spi_data->fd, iocontrol_code, msg) == -1) {
msg_cerr("%s: ioctl: %s\n", __func__, strerror(errno));
return -1;
}
return 0;
}
static struct spi_master spi_master_linux = {
.features = SPI_MASTER_4BA,
.max_data_read = MAX_DATA_UNSPECIFIED, /* TODO? */
.max_data_write = MAX_DATA_UNSPECIFIED, /* TODO? */
.command = linux_spi_send_command,
.multicommand = default_spi_send_multicommand,
.read = linux_spi_read,
.write_256 = linux_spi_write_256,
.write_aai = default_spi_write_aai,
};
/* Read max buffer size from sysfs, or use page size as fallback. */
static size_t get_max_kernel_buf_size()
{
size_t result = 0;
FILE *fp;
fp = fopen(BUF_SIZE_FROM_SYSFS, "r");
if (!fp) {
msg_pwarn("Cannot open %s: %s.\n", BUF_SIZE_FROM_SYSFS, strerror(errno));
goto out;
}
char buf[10];
if (!fgets(buf, sizeof(buf), fp)) {
if (feof(fp))
msg_pwarn("Cannot read %s: file is empty.\n", BUF_SIZE_FROM_SYSFS);
else
msg_pwarn("Cannot read %s: %s.\n", BUF_SIZE_FROM_SYSFS, strerror(errno));
goto out;
}
long int tmp;
errno = 0;
tmp = strtol(buf, NULL, 0);
if ((tmp < 0) || errno) {
msg_pwarn("Buffer size %ld from %s seems wrong.\n", tmp, BUF_SIZE_FROM_SYSFS);
} else {
msg_pdbg("%s: Using value from %s as max buffer size.\n", __func__, BUF_SIZE_FROM_SYSFS);
result = (size_t)tmp;
}
out:
if (fp)
fclose(fp);
if (!result) {
msg_pdbg("%s: Using page size as max buffer size.\n", __func__);
result = (size_t)getpagesize();
}
return result;
}
int linux_spi_init(void)
{
char *p, *endp, *dev;
uint32_t speed_hz = 2 * 1000 * 1000;
/* FIXME: make the following configurable by CLI options. */
/* SPI mode 0 (beware this also includes: MSB first, CS active low and others */
const uint8_t mode = SPI_MODE_0;
const uint8_t bits = 8;
int fd;
size_t max_kernel_buf_size;
struct linux_spi_data *spi_data;
p = extract_programmer_param("spispeed");
if (p && strlen(p)) {
speed_hz = (uint32_t)strtoul(p, &endp, 10) * 1000;
if (p == endp || speed_hz == 0) {
msg_perr("%s: invalid clock: %s kHz\n", __func__, p);
free(p);
return 1;
}
} else {
msg_pinfo("Using default %"PRIu32
"kHz clock. Use 'spispeed' parameter to override.\n",
speed_hz / 1000);
}
free(p);
dev = extract_programmer_param("dev");
if (!dev || !strlen(dev)) {
msg_perr("No SPI device given. Use flashrom -p "
"linux_spi:dev=/dev/spidevX.Y\n");
free(dev);
return 1;
}
msg_pdbg("Using device %s\n", dev);
if ((fd = open(dev, O_RDWR)) == -1) {
msg_perr("%s: failed to open %s: %s\n", __func__,
dev, strerror(errno));
free(dev);
return 1;
}
free(dev);
if (ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed_hz) == -1) {
msg_perr("%s: failed to set speed to %"PRIu32"Hz: %s\n",
__func__, speed_hz, strerror(errno));
goto init_err;
}
msg_pdbg("Using %"PRIu32"kHz clock\n", speed_hz / 1000);
if (ioctl(fd, SPI_IOC_WR_MODE, &mode) == -1) {
msg_perr("%s: failed to set SPI mode to 0x%02x: %s\n",
__func__, mode, strerror(errno));
goto init_err;
}
if (ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bits) == -1) {
msg_perr("%s: failed to set the number of bits per SPI word to %u: %s\n",
__func__, bits == 0 ? 8 : bits, strerror(errno));
goto init_err;
}
max_kernel_buf_size = get_max_kernel_buf_size();
msg_pdbg("%s: max_kernel_buf_size: %zu\n", __func__, max_kernel_buf_size);
spi_data = calloc(1, sizeof(*spi_data));
if (!spi_data) {
msg_perr("Unable to allocated space for SPI master data\n");
goto init_err;
}
spi_data->fd = fd;
spi_data->max_kernel_buf_size = max_kernel_buf_size;
spi_master_linux.data = spi_data;
if (register_shutdown(linux_spi_shutdown, spi_data)) {
free(spi_data);
goto init_err;
}
register_spi_master(&spi_master_linux);
return 0;
init_err:
close(fd);
return 1;
}
#endif // CONFIG_LINUX_SPI == 1