MLK-11937: mtd: spi-nor: add DDR quad read support for Micron

This patch adds the DDR(or DTR) quad read support for the Micron
SPI NOR flash.

Signed-off-by: Han Xu <b45815@freescale.com>

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index 765f8a1..57c9c65 100644 (file)
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -1301,6 +1301,9 @@ static int set_ddr_quad_mode(struct spi_nor *nor, const struct flash_info *info)
                        return status;
                }
                return status;
+       case CFI_MFR_ST: /* Micron, actually */
+               /* DTR quad read works with the Extended SPI protocol. */
+               return 0;
        default:
                return -EINVAL;
        }
@@ -1498,6 +1501,8 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode)
        case SPI_NOR_DDR_QUAD:
                if (JEDEC_MFR(info) == CFI_MFR_AMD) { /* Spansion */
                        nor->read_opcode = SPINOR_OP_READ_1_4_4_D;
+               } else if (JEDEC_MFR(info) == CFI_MFR_ST) {
+                       nor->read_opcode = SPINOR_OP_READ_1_1_4_D;
                } else {
                        dev_err(dev, "DDR Quad Read is not supported.\n");
                        return -EINVAL;

diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index 1d0b9fb..7328180 100644 (file)
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -46,7 +46,8 @@
 #define SPINOR_OP_READ_FAST    0x0b    /* Read data bytes (high frequency) */
 #define SPINOR_OP_READ_1_1_2   0x3b    /* Read data bytes (Dual SPI) */
 #define SPINOR_OP_READ_1_1_4   0x6b    /* Read data bytes (Quad SPI) */
-#define SPINOR_OP_READ_1_4_4_D 0xeb    /* Read data bytes (DDR Quad SPI) */
+#define SPINOR_OP_READ_1_1_4_D 0x6d    /* Read data bytes (DDR Quad SPI) */
+#define SPINOR_OP_READ_1_4_4_D 0xed    /* Read data bytes (DDR Quad SPI) */
 #define SPINOR_OP_PP           0x02    /* Page program (up to 256 bytes) */
 #define SPINOR_OP_BE_4K                0x20    /* Erase 4KiB block */
 #define SPINOR_OP_BE_4K_PMC    0xd7    /* Erase 4KiB block on PMC chips */