[U-Boot] [V4 1/2] sf: Add clear flag status register operation on Micron chips

[Hou Zhiqiang]

Hi Jagan,

Do you have any feedback?

> -----Original Message-----
> From: Zhiqiang Hou [mailto:B48286 at freescale.com]
> Sent: 2015年7月23日 17:54
> To: u-boot at lists.denx.de; jteki at openedev.com
> Cc: Sun York-R58495; Hu Mingkai-B21284; Hou Zhiqiang-B48286; Hu Mingkai-
> B21284
> Subject: [V4 1/2] sf: Add clear flag status register operation on Micron
> chips
> 
> From: Hou Zhiqiang <B48286 at freescale.com>
> 
> Add clear flag status register operation that was required by Micron SPI
> flash chips after reading the flag status register to check if the erase
> and program operations complete or an error occur.
> 
> Signed-off-by: Hou Zhiqiang <B48286 at freescale.com>
> Signed-off-by: Mingkai.Hu <Mingkai.Hu at freescale.com>
> ---
>  drivers/mtd/spi/sf_internal.h |  9 +++++++++
>  drivers/mtd/spi/sf_ops.c      | 40 ++++++++++++++++++++++++++++++++-----
> ---
>  2 files changed, 41 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/mtd/spi/sf_internal.h
> b/drivers/mtd/spi/sf_internal.h index 9fb5557..703d4a7 100644
> --- a/drivers/mtd/spi/sf_internal.h
> +++ b/drivers/mtd/spi/sf_internal.h
> @@ -73,6 +73,7 @@ enum {
>  #define CMD_WRITE_ENABLE		0x06
>  #define CMD_READ_CONFIG			0x35
>  #define CMD_FLAG_STATUS			0x70
> +#define CMD_CLEAR_FLAG_STATUS		0x50
> 
>  /* Read commands */
>  #define CMD_READ_ARRAY_SLOW		0x03
> @@ -96,6 +97,8 @@ enum {
>  #define STATUS_QEB_WINSPAN		(1 << 1)
>  #define STATUS_QEB_MXIC		(1 << 6)
>  #define STATUS_PEC			(1 << 7)
> +#define STATUS_PROT			(1 << 1)
> +#define STATUS_ERASE			(1 << 5)
> 
>  /* Flash timeout values */
>  #define SPI_FLASH_PROG_TIMEOUT		(2 * CONFIG_SYS_HZ)
> @@ -182,6 +185,12 @@ static inline int spi_flash_cmd_write_disable(struct
> spi_flash *flash)
>  	return spi_flash_cmd(flash->spi, CMD_WRITE_DISABLE, NULL, 0);  }
> 
> +/* Clear flag status register */
> +static inline int spi_flash_cmd_clear_flag_status(struct spi_slave
> +*spi) {
> +	return spi_flash_cmd(spi, CMD_CLEAR_FLAG_STATUS, NULL, 0); }
> +
>  /*
>   * Send the read status command to the device and wait for the wip
>   * (write-in-progress) bit to clear itself.
> diff --git a/drivers/mtd/spi/sf_ops.c b/drivers/mtd/spi/sf_ops.c index
> 38592f5..cbb9f00 100644
> --- a/drivers/mtd/spi/sf_ops.c
> +++ b/drivers/mtd/spi/sf_ops.c
> @@ -160,6 +160,7 @@ static int spi_flash_poll_status(struct spi_slave
> *spi, unsigned long timeout,
>  	unsigned long timebase;
>  	unsigned long flags = SPI_XFER_BEGIN;
>  	int ret;
> +	int out_of_time = 1;
>  	u8 status;
>  	u8 check_status = 0x0;
> 
> @@ -182,22 +183,45 @@ static int spi_flash_poll_status(struct spi_slave
> *spi, unsigned long timeout,
>  		WATCHDOG_RESET();
> 
>  		ret = spi_xfer(spi, 8, NULL, &status, 0);
> -		if (ret)
> +		if (ret) {
> +			spi_xfer(spi, 0, NULL, NULL, SPI_XFER_END);
>  			return -1;
> +		}
> 
> -		if ((status & poll_bit) == check_status)
> +		if ((status & poll_bit) == check_status) {
> +			out_of_time = 0;
>  			break;
> +		}
> 
>  	} while (get_timer(timebase) < timeout);
> 
>  	spi_xfer(spi, 0, NULL, NULL, SPI_XFER_END);
> 
> -	if ((status & poll_bit) == check_status)
> -		return 0;
> +	if (out_of_time) {
> +		/* Timed out */
> +		debug("SF: time out!\n");
> +		if (cmd == CMD_FLAG_STATUS) {
> +			if (spi_flash_cmd_clear_flag_status(spi) < 0)
> +				debug("SF: clear flag status failed\n");
> +		}
> +		ret = -1;
> +	}
> +#ifdef CONFIG_SPI_FLASH_STMICRO
> +	else if (cmd == CMD_FLAG_STATUS) {
> +		if (!(status & (STATUS_PROT | STATUS_ERASE))) {
> +			ret = 0;
> +		} else {
> +			debug("SF: flag status error");
> +			ret = -1;
> +		}
> 
> -	/* Timed out */
> -	debug("SF: time out!\n");
> -	return -1;
> +		if (spi_flash_cmd_clear_flag_status(spi) < 0) {
> +			debug("SF: clear flag status failed\n");
> +			ret = -1;
> +		}
> +	}
> +#endif
> +	return ret;
>  }
> 
>  int spi_flash_cmd_wait_ready(struct spi_flash *flash, unsigned long
> timeout) @@ -252,7 +276,7 @@ int spi_flash_write_common(struct spi_flash
> *flash, const u8 *cmd,
> 
>  	ret = spi_flash_cmd_wait_ready(flash, timeout);
>  	if (ret < 0) {
> -		debug("SF: write %s timed out\n",
> +		debug("SF: write %s failed\n",
>  		      timeout == SPI_FLASH_PROG_TIMEOUT ?
>  			"program" : "page erase");
>  		return ret;
> --
> 2.1.0.27.g96db324

Thanks,
Zhiqiang