sf: probe: Add support for SST_WP
Most of the SST flashes needs to write up using SST_WP, AAI
Word Program, so added a flag param on spi_flash_params table.
SST flashes, which supports SST_WP need to use a WP write
sst_write_wp instead of common flash write.
Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
diff --git a/drivers/mtd/spi/spi_flash_ops.c b/drivers/mtd/spi/spi_flash_ops.c
index 6133363..79381b1 100644
--- a/drivers/mtd/spi/spi_flash_ops.c
+++ b/drivers/mtd/spi/spi_flash_ops.c
@@ -312,3 +312,96 @@
return ret;
}
+
+#ifdef CONFIG_SPI_FLASH_SST
+static int sst_byte_write(struct spi_flash *flash, u32 offset, const void *buf)
+{
+ int ret;
+ u8 cmd[4] = {
+ CMD_SST_BP,
+ offset >> 16,
+ offset >> 8,
+ offset,
+ };
+
+ debug("BP[%02x]: 0x%p => cmd = { 0x%02x 0x%06x }\n",
+ spi_w8r8(flash->spi, CMD_READ_STATUS), buf, cmd[0], offset);
+
+ ret = spi_flash_cmd_write_enable(flash);
+ if (ret)
+ return ret;
+
+ ret = spi_flash_cmd_write(flash->spi, cmd, sizeof(cmd), buf, 1);
+ if (ret)
+ return ret;
+
+ return spi_flash_cmd_wait_ready(flash, SPI_FLASH_PROG_TIMEOUT);
+}
+
+int sst_write_wp(struct spi_flash *flash, u32 offset, size_t len,
+ const void *buf)
+{
+ size_t actual, cmd_len;
+ int ret;
+ u8 cmd[4];
+
+ ret = spi_claim_bus(flash->spi);
+ if (ret) {
+ debug("SF: Unable to claim SPI bus\n");
+ return ret;
+ }
+
+ /* If the data is not word aligned, write out leading single byte */
+ actual = offset % 2;
+ if (actual) {
+ ret = sst_byte_write(flash, offset, buf);
+ if (ret)
+ goto done;
+ }
+ offset += actual;
+
+ ret = spi_flash_cmd_write_enable(flash);
+ if (ret)
+ goto done;
+
+ cmd_len = 4;
+ cmd[0] = CMD_SST_AAI_WP;
+ cmd[1] = offset >> 16;
+ cmd[2] = offset >> 8;
+ cmd[3] = offset;
+
+ for (; actual < len - 1; actual += 2) {
+ debug("WP[%02x]: 0x%p => cmd = { 0x%02x 0x%06x }\n",
+ spi_w8r8(flash->spi, CMD_READ_STATUS), buf + actual,
+ cmd[0], offset);
+
+ ret = spi_flash_cmd_write(flash->spi, cmd, cmd_len,
+ buf + actual, 2);
+ if (ret) {
+ debug("SF: sst word program failed\n");
+ break;
+ }
+
+ ret = spi_flash_cmd_wait_ready(flash, SPI_FLASH_PROG_TIMEOUT);
+ if (ret)
+ break;
+
+ cmd_len = 1;
+ offset += 2;
+ }
+
+ if (!ret)
+ ret = spi_flash_cmd_write_disable(flash);
+
+ /* If there is a single trailing byte, write it out */
+ if (!ret && actual != len)
+ ret = sst_byte_write(flash, offset, buf + actual);
+
+ done:
+ debug("SF: sst: program %s %zu bytes @ 0x%zx\n",
+ ret ? "failure" : "success", len, offset - actual);
+
+ spi_release_bus(flash->spi);
+ return ret;
+}
+#endif
