Commit be4ea89c authored by Ben Hutchings's avatar Ben Hutchings Committed by David S. Miller
Browse files

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: default avatarBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 1ab00629

drivers/net/sfc/falcon.c

+37 −21
Original line number Diff line number Diff line
@@ -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;
@@ -1700,27 +1713,30 @@ 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;

	}

	EFX_ERR(spi->efx,

		"timed out waiting for device %d last status=0x%02x\n",

		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);

	}

}



int falcon_spi_read(const struct efx_spi_device *spi, loff_t start,

		    size_t len, size_t *retlen, u8 *buffer)
@@ -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;

drivers/net/sfc/mtd.c

+1 −1
Original line number Diff line number Diff line
@@ -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;

drivers/net/sfc/spi.h

+1 −1
Original line number Diff line number Diff line
@@ -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,

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