spi/bcm63xx-hsspi: add support for dual spi read/write
authorJonas Gorski <jogo@openwrt.org>
Sun, 23 Aug 2015 20:49:32 +0000 (22:49 +0200)
committerMark Brown <broonie@kernel.org>
Tue, 25 Aug 2015 16:33:49 +0000 (17:33 +0100)
Add support for dual read/writes on spi-bcm63xx-hsspi. This has been
tested with a s25fl129p1 dual read capable spi flash, with a nice speed
improvement:

serial read:

root@OpenWrt:/# time dd if=/dev/mtd4 of=/dev/null bs=8192
2032+0 records in
2032+0 records out
real    0m 4.39s
user    0m 0.00s
sys     0m 1.55s

dual read:

root@OpenWrt:/# time dd if=/dev/mtd4 of=/dev/null bs=8192
2032+0 records in
2032+0 records out
real    0m 3.09s
user    0m 0.00s
sys     0m 1.56s

Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
drivers/spi/spi-bcm63xx-hsspi.c

index f5ca6dc3a157879895aa0953c4c6681594b3d5ff..55789f7cda9280b2f0d21b65b6a7f3c019780047 100644 (file)
@@ -76,6 +76,7 @@
 #define HSSPI_FIFO_REG(x)                      (0x200 + (x) * 0x200)
 
 
+#define HSSPI_OP_MULTIBIT                      BIT(11)
 #define HSSPI_OP_CODE_SHIFT                    13
 #define HSSPI_OP_SLEEP                         (0 << HSSPI_OP_CODE_SHIFT)
 #define HSSPI_OP_READ_WRITE                    (1 << HSSPI_OP_CODE_SHIFT)
@@ -171,9 +172,12 @@ static int bcm63xx_hsspi_do_txrx(struct spi_device *spi, struct spi_transfer *t)
        if (opcode != HSSPI_OP_READ)
                step_size -= HSSPI_OPCODE_LEN;
 
-       __raw_writel(0 << MODE_CTRL_PREPENDBYTE_CNT_SHIFT |
-                    2 << MODE_CTRL_MULTIDATA_WR_STRT_SHIFT |
-                    2 << MODE_CTRL_MULTIDATA_RD_STRT_SHIFT | 0xff,
+       if ((opcode == HSSPI_OP_READ && t->rx_nbits == SPI_NBITS_DUAL) ||
+           (opcode == HSSPI_OP_WRITE && t->tx_nbits == SPI_NBITS_DUAL))
+               opcode |= HSSPI_OP_MULTIBIT;
+
+       __raw_writel(1 << MODE_CTRL_MULTIDATA_WR_SIZE_SHIFT |
+                    1 << MODE_CTRL_MULTIDATA_RD_SIZE_SHIFT | 0xff,
                     bs->regs + HSSPI_PROFILE_MODE_CTRL_REG(chip_select));
 
        while (pending > 0) {
@@ -374,7 +378,8 @@ static int bcm63xx_hsspi_probe(struct platform_device *pdev)
        master->num_chipselect = 8;
        master->setup = bcm63xx_hsspi_setup;
        master->transfer_one_message = bcm63xx_hsspi_transfer_one;
-       master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
+       master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH |
+                           SPI_RX_DUAL | SPI_TX_DUAL;
        master->bits_per_word_mask = SPI_BPW_MASK(8);
        master->auto_runtime_pm = true;