-----Original Message----- From: Simon Guinot [mailto:sguinot@lacie.com] Sent: Monday, May 02, 2011 2:40 AM To: Prafulla Wadaskar; Albert ARIBAUD; Wolfgang Denk Cc: u-boot@lists.denx.de; Simon Guinot Subject: [PATCH v2 2/6] sf: disable write protection for Macronix flash
Signed-off-by: Simon Guinot sguinot@lacie.com
drivers/mtd/spi/macronix.c | 87 ++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 87 insertions(+), 0 deletions(-)
diff --git a/drivers/mtd/spi/macronix.c b/drivers/mtd/spi/macronix.c index 8e4d71c..b587ac9 100644 --- a/drivers/mtd/spi/macronix.c +++ b/drivers/mtd/spi/macronix.c @@ -49,6 +49,10 @@ #define CMD_MX25XX_DP 0xb9 /* Deep Power-down */ #define CMD_MX25XX_RES 0xab /* Release from DP, and Read Signature */
+/* Status registers */ +#define MX25XX_SR_BP (0xF << 2) /* Block Protect */ +#define MX25XX_SR_SRWP (1 << 7) /* Write Protect */
struct macronix_spi_flash_params { u16 idcode; u16 page_size; @@ -120,6 +124,86 @@ static const struct macronix_spi_flash_params macronix_spi_flash_table[] = { }, };
+static int macronix_write_status(struct spi_flash *flash, u8 sr) +{
- u8 cmd[2];
- int ret;
- ret = spi_flash_cmd(flash->spi, CMD_MX25XX_WREN, NULL, 0);
- if (ret < 0) {
debug("SF: Enabling Write failed\n");return ret;- }
- cmd[0] = CMD_MX25XX_WRSR;
- cmd[1] = sr;
- ret = spi_xfer(flash->spi, 16, cmd, NULL, SPI_XFER_BEGIN);
- if (ret) {
debug("SF: fail to write status register\n");return ret;- }
- spi_xfer(flash->spi, 0, NULL, NULL, SPI_XFER_END);
- ret = spi_flash_cmd_wait_ready(flash, SPI_FLASH_PROG_TIMEOUT);
- if (ret < 0) {
debug("SF: write status register timed out\n");return ret;- }
- return 0;
+}
+static int macronix_read_status(struct spi_flash *flash, u8 *sr) +{
- u8 cmd = CMD_MX25XX_RDSR;
- int ret;
- ret = spi_xfer(flash->spi, 8, &cmd, NULL, SPI_XFER_BEGIN);
- if (ret) {
debug("SF: Failed to send command %02x: %d\n", cmd, ret);return ret;- }
- ret = spi_xfer(flash->spi, 8, NULL, sr, 0);
- if (ret) {
debug("SF: fail to read status register: %d\n", ret);return ret;- }
- spi_xfer(flash->spi, 0, NULL, NULL, SPI_XFER_END);
- return 0;
+}
+static int macronix_disable_protect(struct spi_flash *flash) +{
- int ret;
- u8 sr;
- ret = macronix_read_status(flash, &sr);
- if (ret)
return ret;- if ((sr & MX25XX_SR_BP) == 0)
return ret;- /* Disable status register write protection. */
- sr &= ~MX25XX_SR_SRWP;
- ret = macronix_write_status(flash, sr);
- if (ret)
return ret;- /* Disable block protection. */
- sr &= ~MX25XX_SR_BP;
- ret = macronix_write_status(flash, sr);
- if (ret)
return ret;- printf("SF: disable write protection\n");
- return 0;
+}
static int macronix_write(struct spi_flash *flash, u32 offset, size_t len, const void *buf) { @@ -223,5 +307,8 @@ struct spi_flash *spi_flash_probe_macronix(struct spi_slave *spi, u8 *idcode) * params->sectors_per_block; mcx->flash.size = mcx->flash.sector_size * params->nr_blocks;
- if (macronix_disable_protect(&mcx->flash))
printf("SF: disable write protection failed\n");
This will forced disable the flash being written. What if some one has purposely protected certain flash sectors?
This feature should be addressed through protect CLI
Regards.. Prafulla . .
return &mcx->flash; } -- 1.6.3.1