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sfc: Clean up waits for flash/EEPROM operations

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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>
This commit is contained in:
Ben Hutchings 2008-12-12 21:33:50 -08:00 committed by David S. Miller
parent 1ab00629f0
commit be4ea89c8d
3 changed files with 39 additions and 23 deletions
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58
drivers/net/sfc/falcon.c
View File

@ -1607,24 +1607,37 @@ void falcon_fini_interrupt(struct efx_nic *efx)
#define FALCON_SPI_MAX_LEN sizeof(efx_oword_t)
static int falcon_spi_poll(struct efx_nic *efx)
{
efx_oword_t reg;
falcon_read(efx, &reg, EE_SPI_HCMD_REG_KER);
return EFX_OWORD_FIELD(reg, EE_SPI_HCMD_CMD_EN) ? -EBUSY : 0;
}
/* Wait for SPI command completion */
static int falcon_spi_wait(struct efx_nic *efx)
{
unsigned long timeout = jiffies + DIV_ROUND_UP(HZ, 10);
efx_oword_t reg;
bool cmd_en, timer_active;
/* Most commands will finish quickly, so we start polling at
* very short intervals. Sometimes the command may have to
* wait for VPD or expansion ROM access outside of our
* control, so we allow up to 100 ms. */
unsigned long timeout = jiffies + 1 + DIV_ROUND_UP(HZ, 10);
int i;
for (i = 0; i < 10; i++) {
if (!falcon_spi_poll(efx))
return 0;
udelay(10);
}
for (;;) {
falcon_read(efx, &reg, EE_SPI_HCMD_REG_KER);
cmd_en = EFX_OWORD_FIELD(reg, EE_SPI_HCMD_CMD_EN);
timer_active = EFX_OWORD_FIELD(reg, EE_WR_TIMER_ACTIVE);
if (!cmd_en && !timer_active)
if (!falcon_spi_poll(efx))
return 0;
if (time_after_eq(jiffies, timeout)) {
EFX_ERR(efx, "timed out waiting for SPI\n");
return -ETIMEDOUT;
}
cpu_relax();
schedule_timeout_uninterruptible(1);
}
}
@ -1643,8 +1656,8 @@ int falcon_spi_cmd(const struct efx_spi_device *spi,
return -EINVAL;
BUG_ON(!mutex_is_locked(&efx->spi_lock));
/* Check SPI not currently being accessed */
rc = falcon_spi_wait(efx);
/* Check that previous command is not still running */
rc = falcon_spi_poll(efx);
if (rc)
return rc;
@ -1700,26 +1713,29 @@ efx_spi_munge_command(const struct efx_spi_device *spi,
return command | (((address >> 8) & spi->munge_address) << 3);
}
int falcon_spi_fast_wait(const struct efx_spi_device *spi)
/* Wait up to 10 ms for buffered write completion */
int falcon_spi_wait_write(const struct efx_spi_device *spi)
{
struct efx_nic *efx = spi->efx;
unsigned long timeout = jiffies + 1 + DIV_ROUND_UP(HZ, 100);
u8 status;
int i, rc;
/* Wait up to 1000us for flash/EEPROM to finish a fast operation. */
for (i = 0; i < 50; i++) {
udelay(20);
int rc;
for (;;) {
rc = falcon_spi_cmd(spi, SPI_RDSR, -1, NULL,
&status, sizeof(status));
if (rc)
return rc;
if (!(status & SPI_STATUS_NRDY))
return 0;
if (time_after_eq(jiffies, timeout)) {
EFX_ERR(efx, "SPI write timeout on device %d"
" last status=0x%02x\n",
spi->device_id, status);
return -ETIMEDOUT;
}
schedule_timeout_uninterruptible(1);
}
EFX_ERR(spi->efx,
"timed out waiting for device %d last status=0x%02x\n",
spi->device_id, status);
return -ETIMEDOUT;
}
int falcon_spi_read(const struct efx_spi_device *spi, loff_t start,
@ -1773,7 +1789,7 @@ int falcon_spi_write(const struct efx_spi_device *spi, loff_t start,
if (rc)
break;
rc = falcon_spi_fast_wait(spi);
rc = falcon_spi_wait_write(spi);
if (rc)
break;

2
drivers/net/sfc/mtd.c
View File

@ -76,7 +76,7 @@ static int efx_spi_unlock(const struct efx_spi_device *spi)
rc = falcon_spi_cmd(spi, SPI_WRSR, -1, &status, NULL, sizeof(status));
if (rc)
return rc;
rc = falcon_spi_fast_wait(spi);
rc = falcon_spi_wait_write(spi);
if (rc)
return rc;

2
drivers/net/sfc/spi.h
View File

@ -69,7 +69,7 @@ struct efx_spi_device {
int falcon_spi_cmd(const struct efx_spi_device *spi, unsigned int command,
int address, const void* in, void *out, size_t len);
int falcon_spi_fast_wait(const struct efx_spi_device *spi);
int falcon_spi_wait_write(const struct efx_spi_device *spi);
int falcon_spi_read(const struct efx_spi_device *spi, loff_t start,
size_t len, size_t *retlen, u8 *buffer);
int falcon_spi_write(const struct efx_spi_device *spi, loff_t start,