linux/drivers/net/sfc/mtd.c
Ben Hutchings be4ea89c8d sfc: Clean up waits for flash/EEPROM operations
Make falcon_spi_wait() ignore the write timer - it is only relevant to
write commands, it only works for the device that contains VPD, and it
might not be initialised properly at all.

Rename falcon_spi_fast_wait() to falcon_spi_wait_write(), reflecting
its use, and make it wait up to 10 ms (not 1 ms) since buffered writes
to EEPROM may take this long to complete.

Make both wait functions sleep instead of busy-waiting.

Replace wait for command completion at top of falcon_spi_cmd() with a
single poll; no command should be running when the function starts.

Correct some comments.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-12 21:57:35 -08:00

268 lines
6.3 KiB
C

/****************************************************************************
* Driver for Solarflare Solarstorm network controllers and boards
* Copyright 2005-2006 Fen Systems Ltd.
* Copyright 2006-2008 Solarflare Communications Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation, incorporated herein by reference.
*/
#include <linux/module.h>
#include <linux/mtd/mtd.h>
#include <linux/delay.h>
#define EFX_DRIVER_NAME "sfc_mtd"
#include "net_driver.h"
#include "spi.h"
#define EFX_SPI_VERIFY_BUF_LEN 16
struct efx_mtd {
const struct efx_spi_device *spi;
struct mtd_info mtd;
char name[IFNAMSIZ + 20];
};
/* SPI utilities */
static int efx_spi_slow_wait(struct efx_mtd *efx_mtd, bool uninterruptible)
{
const struct efx_spi_device *spi = efx_mtd->spi;
struct efx_nic *efx = spi->efx;
u8 status;
int rc, i;
/* Wait up to 4s for flash/EEPROM to finish a slow operation. */
for (i = 0; i < 40; i++) {
__set_current_state(uninterruptible ?
TASK_UNINTERRUPTIBLE : TASK_INTERRUPTIBLE);
schedule_timeout(HZ / 10);
rc = falcon_spi_cmd(spi, SPI_RDSR, -1, NULL,
&status, sizeof(status));
if (rc)
return rc;
if (!(status & SPI_STATUS_NRDY))
return 0;
if (signal_pending(current))
return -EINTR;
}
EFX_ERR(efx, "timed out waiting for %s\n", efx_mtd->name);
return -ETIMEDOUT;
}
static int efx_spi_unlock(const struct efx_spi_device *spi)
{
const u8 unlock_mask = (SPI_STATUS_BP2 | SPI_STATUS_BP1 |
SPI_STATUS_BP0);
u8 status;
int rc;
rc = falcon_spi_cmd(spi, SPI_RDSR, -1, NULL, &status, sizeof(status));
if (rc)
return rc;
if (!(status & unlock_mask))
return 0; /* already unlocked */
rc = falcon_spi_cmd(spi, SPI_WREN, -1, NULL, NULL, 0);
if (rc)
return rc;
rc = falcon_spi_cmd(spi, SPI_SST_EWSR, -1, NULL, NULL, 0);
if (rc)
return rc;
status &= ~unlock_mask;
rc = falcon_spi_cmd(spi, SPI_WRSR, -1, &status, NULL, sizeof(status));
if (rc)
return rc;
rc = falcon_spi_wait_write(spi);
if (rc)
return rc;
return 0;
}
static int efx_spi_erase(struct efx_mtd *efx_mtd, loff_t start, size_t len)
{
const struct efx_spi_device *spi = efx_mtd->spi;
unsigned pos, block_len;
u8 empty[EFX_SPI_VERIFY_BUF_LEN];
u8 buffer[EFX_SPI_VERIFY_BUF_LEN];
int rc;
if (len != spi->erase_size)
return -EINVAL;
if (spi->erase_command == 0)
return -EOPNOTSUPP;
rc = efx_spi_unlock(spi);
if (rc)
return rc;
rc = falcon_spi_cmd(spi, SPI_WREN, -1, NULL, NULL, 0);
if (rc)
return rc;
rc = falcon_spi_cmd(spi, spi->erase_command, start, NULL, NULL, 0);
if (rc)
return rc;
rc = efx_spi_slow_wait(efx_mtd, false);
/* Verify the entire region has been wiped */
memset(empty, 0xff, sizeof(empty));
for (pos = 0; pos < len; pos += block_len) {
block_len = min(len - pos, sizeof(buffer));
rc = falcon_spi_read(spi, start + pos, block_len, NULL, buffer);
if (rc)
return rc;
if (memcmp(empty, buffer, block_len))
return -EIO;
/* Avoid locking up the system */
cond_resched();
if (signal_pending(current))
return -EINTR;
}
return rc;
}
/* MTD interface */
static int efx_mtd_read(struct mtd_info *mtd, loff_t start, size_t len,
size_t *retlen, u8 *buffer)
{
struct efx_mtd *efx_mtd = mtd->priv;
const struct efx_spi_device *spi = efx_mtd->spi;
struct efx_nic *efx = spi->efx;
int rc;
rc = mutex_lock_interruptible(&efx->spi_lock);
if (rc)
return rc;
rc = falcon_spi_read(spi, FALCON_FLASH_BOOTCODE_START + start,
len, retlen, buffer);
mutex_unlock(&efx->spi_lock);
return rc;
}
static int efx_mtd_erase(struct mtd_info *mtd, struct erase_info *erase)
{
struct efx_mtd *efx_mtd = mtd->priv;
struct efx_nic *efx = efx_mtd->spi->efx;
int rc;
rc = mutex_lock_interruptible(&efx->spi_lock);
if (rc)
return rc;
rc = efx_spi_erase(efx_mtd, FALCON_FLASH_BOOTCODE_START + erase->addr,
erase->len);
mutex_unlock(&efx->spi_lock);
if (rc == 0) {
erase->state = MTD_ERASE_DONE;
} else {
erase->state = MTD_ERASE_FAILED;
erase->fail_addr = 0xffffffff;
}
mtd_erase_callback(erase);
return rc;
}
static int efx_mtd_write(struct mtd_info *mtd, loff_t start,
size_t len, size_t *retlen, const u8 *buffer)
{
struct efx_mtd *efx_mtd = mtd->priv;
const struct efx_spi_device *spi = efx_mtd->spi;
struct efx_nic *efx = spi->efx;
int rc;
rc = mutex_lock_interruptible(&efx->spi_lock);
if (rc)
return rc;
rc = falcon_spi_write(spi, FALCON_FLASH_BOOTCODE_START + start,
len, retlen, buffer);
mutex_unlock(&efx->spi_lock);
return rc;
}
static void efx_mtd_sync(struct mtd_info *mtd)
{
struct efx_mtd *efx_mtd = mtd->priv;
struct efx_nic *efx = efx_mtd->spi->efx;
int rc;
mutex_lock(&efx->spi_lock);
rc = efx_spi_slow_wait(efx_mtd, true);
mutex_unlock(&efx->spi_lock);
if (rc)
EFX_ERR(efx, "%s sync failed (%d)\n", efx_mtd->name, rc);
return;
}
void efx_mtd_remove(struct efx_nic *efx)
{
if (efx->spi_flash && efx->spi_flash->mtd) {
struct efx_mtd *efx_mtd = efx->spi_flash->mtd;
int rc;
for (;;) {
rc = del_mtd_device(&efx_mtd->mtd);
if (rc != -EBUSY)
break;
ssleep(1);
}
WARN_ON(rc);
kfree(efx_mtd);
}
}
void efx_mtd_rename(struct efx_nic *efx)
{
if (efx->spi_flash && efx->spi_flash->mtd) {
struct efx_mtd *efx_mtd = efx->spi_flash->mtd;
snprintf(efx_mtd->name, sizeof(efx_mtd->name),
"%s sfc_flash_bootrom", efx->name);
}
}
int efx_mtd_probe(struct efx_nic *efx)
{
struct efx_spi_device *spi = efx->spi_flash;
struct efx_mtd *efx_mtd;
if (!spi || spi->size <= FALCON_FLASH_BOOTCODE_START)
return -ENODEV;
efx_mtd = kzalloc(sizeof(*efx_mtd), GFP_KERNEL);
if (!efx_mtd)
return -ENOMEM;
efx_mtd->spi = spi;
spi->mtd = efx_mtd;
efx_mtd->mtd.type = MTD_NORFLASH;
efx_mtd->mtd.flags = MTD_CAP_NORFLASH;
efx_mtd->mtd.size = spi->size - FALCON_FLASH_BOOTCODE_START;
efx_mtd->mtd.erasesize = spi->erase_size;
efx_mtd->mtd.writesize = 1;
efx_mtd_rename(efx);
efx_mtd->mtd.owner = THIS_MODULE;
efx_mtd->mtd.priv = efx_mtd;
efx_mtd->mtd.name = efx_mtd->name;
efx_mtd->mtd.erase = efx_mtd_erase;
efx_mtd->mtd.read = efx_mtd_read;
efx_mtd->mtd.write = efx_mtd_write;
efx_mtd->mtd.sync = efx_mtd_sync;
if (add_mtd_device(&efx_mtd->mtd)) {
kfree(efx_mtd);
spi->mtd = NULL;
/* add_mtd_device() returns 1 if the MTD table is full */
return -ENOMEM;
}
return 0;
}