sf: Add extended read commands support

Current sf uses FAST_READ command, this patch adds support to
use the different/extended read command.

This implementation will determine the fastest command by taking
the supported commands from the flash and the controller, controller
is always been a priority.

Added rd_cmd support to S25FL256S_64K SPI flash.

Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>

diff --git a/drivers/mtd/spi/spansion.c b/drivers/mtd/spi/spansion.c
index 7f3ab8d15b2e520b4aa6a1da216028965799e74e..b2452064ebcacc52c6ac8052e1d6fad845515456 100644 (file)
--- a/drivers/mtd/spi/spansion.c
+++ b/drivers/mtd/spi/spansion.c
@@ -36,6 +36,7 @@ struct spansion_spi_flash_params {
        u16 idcode2;
        u16 pages_per_sector;
        u16 nr_sectors;
+       u8 rd_cmd;
        const char *name;
 };
 
@@ -108,6 +109,7 @@ static const struct spansion_spi_flash_params spansion_spi_flash_table[] = {
                .idcode2 = 0x4d01,
                .pages_per_sector = 256,
                .nr_sectors = 512,
+               .rd_cmd = READ_CMD_FULL,
                .name = "S25FL256S_64K",
        },
        {
@@ -132,6 +134,7 @@ struct spi_flash *spi_flash_probe_spansion(struct spi_slave *spi, u8 *idcode)
        struct spi_flash *flash;
        unsigned int i;
        unsigned short jedec, ext_jedec;
+       u8 cmd;
 
        jedec = idcode[1] << 8 | idcode[2];
        ext_jedec = idcode[3] << 8 | idcode[4];
@@ -155,6 +158,13 @@ struct spi_flash *spi_flash_probe_spansion(struct spi_slave *spi, u8 *idcode)
                return NULL;
        }
 
+       /* Look for the fastest read cmd */
+       cmd = fls(params->rd_cmd & flash->spi->rd_cmd);
+       if (cmd) {
+               cmd = spi_read_cmds_array[cmd - 1];
+               flash->read_cmd = cmd;
+       }
+
        flash->page_size = 256;
        flash->sector_size = 256 * params->pages_per_sector;
 

diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
index 4db1bbe0545d37b0f1fcb73469ff25cb77275325..832372ec5cdecf62d3739ca711daad66293013b4 100644 (file)
--- a/drivers/mtd/spi/spi_flash.c
+++ b/drivers/mtd/spi/spi_flash.c
@@ -318,7 +318,7 @@ int spi_flash_cmd_read_fast(struct spi_flash *flash, u32 offset,
        if (is_dual == MODE_DUAL_PARALLEL)
                bank_boun = SPI_FLASH_16MB_BOUN << 1;
 
-       cmd[0] = CMD_READ_ARRAY_FAST;
+       cmd[0] = flash->read_cmd;
        cmd[4] = 0x00;
 
        while (len) {
@@ -659,6 +659,9 @@ void *spi_flash_do_alloc(int offset, int size, struct spi_slave *spi,
        flash->write = spi_flash_cmd_write_multi;
        flash->erase = spi_flash_cmd_erase;
 
+       /* Go for default command - if caller don't have any addons */
+       flash->read_cmd = CMD_READ_ARRAY_FAST;
+
        return flash;
 }
 

diff --git a/drivers/spi/zynq_qspi.c b/drivers/spi/zynq_qspi.c
index 0ad2c5e047548e5d9e92a2dec095e71ccdbd7eea..2000cbc1fb800e80e9f573300f7d2c0ef81f0e7e 100644 (file)
--- a/drivers/spi/zynq_qspi.c
+++ b/drivers/spi/zynq_qspi.c
@@ -993,6 +993,7 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
        }
 
        qspi->slave.is_dual = is_dual;
+       qspi->slave.rd_cmd = READ_CMD_FULL;
        qspi->qspi.master.speed_hz = qspi->qspi.master.input_clk_hz / 2;
        qspi->qspi.max_speed_hz = qspi->qspi.master.speed_hz;
        qspi->qspi.master.is_dual = is_dual;

diff --git a/include/spi.h b/include/spi.h
index a80d0f068290b8e4d6205066cbd8bd168ca66be9..e0ac5794e3f87b73e6635e481d2e63b94e473337 100644 (file)
--- a/include/spi.h
+++ b/include/spi.h
@@ -59,6 +59,7 @@
  *   u_page:   Indicates the upper memory page, in dual stacked connection.
  *   max_write_size:   If non-zero, the maximum number of bytes which can
  *             be written at once, excluding command bytes.
+ *   rd_cmd:   Read command.
  */
 struct spi_slave {
        unsigned int    bus;
@@ -66,6 +67,7 @@ struct spi_slave {
        unsigned int    is_dual;
        unsigned int    u_page;
        unsigned int max_write_size;
+       u8 rd_cmd;
 };
 
 /*-----------------------------------------------------------------------

diff --git a/include/spi_flash.h b/include/spi_flash.h
index ebe537fb86faf1fb560d2b839c81f7e320ab623e..7afa5f765304ba41c42220b1d48e23b4889b8f2b 100644 (file)
--- a/include/spi_flash.h
+++ b/include/spi_flash.h
@@ -35,6 +35,29 @@ enum spi_con_topology {
        MODE_DUAL_PARALLEL,
 };
 
+/* Read commands */
+#define CMD_READ_ARRAY_SLOW            0x03
+#define CMD_READ_ARRAY_FAST            0x0b
+#define CMD_READ_DUAL_OUTPUT_FAST      0x3b
+#define CMD_READ_DUAL_IO_FAST          0xbb
+
+static u32 spi_read_cmds_array[] = {
+       CMD_READ_ARRAY_SLOW,
+       CMD_READ_ARRAY_FAST,
+       CMD_READ_DUAL_OUTPUT_FAST,
+       CMD_READ_DUAL_IO_FAST,
+};
+
+enum spi_read_cmds {
+       ARRAY_SLOW = 1 << 0,
+       ARRAY_FAST = 1 << 1,
+       DUAL_OUTPUT_FAST = 1 << 2,
+       DUAL_IO_FAST = 1 << 3,
+};
+
+#define READ_CMD_FULL  ARRAY_SLOW | ARRAY_FAST | DUAL_OUTPUT_FAST | \
+                       DUAL_IO_FAST
+
 struct spi_flash {
        struct spi_slave *spi;
 
@@ -56,6 +79,8 @@ struct spi_flash {
 #endif
        /* Poll cmd - for flash erase/program */
        u8              poll_cmd;
+       /* Read command */
+       u8              read_cmd;
 
        void *memory_map;       /* Address of read-only SPI flash access */
        int             (*read)(struct spi_flash *flash, u32 offset,