target/linux/brcm63xx/patches-4.1/010-4.3-01-spi-bcm63xx-hsspi-add-support-for-dual-spi-read-writ.patch

   1 From 61dc388f577b6f984797949f32c30021d9ea73dc Mon Sep 17 00:00:00 2001
   2 From: Jonas Gorski <jogo@openwrt.org>
   3 Date: Sun, 23 Aug 2015 12:16:02 +0200
   4 Subject: [PATCH V2] spi/bcm63xx-hsspi: add support for dual spi read/write
   5
   6 Add support for dual read/writes on spi-bcm63xx-hsspi. This has been
   7 tested with a s25fl129p1 dual read capable spi flash, with a nice speed
   8 improvement:
   9
  10 serial read:
  11
  12 root@OpenWrt:/# time dd if=/dev/mtd4 of=/dev/null bs=8192
  13 2032+0 records in
  14 2032+0 records out
  15 real    0m 4.39s
  16 user    0m 0.00s
  17 sys     0m 1.55s
  18
  19 dual read:
  20
  21 root@OpenWrt:/# time dd if=/dev/mtd4 of=/dev/null bs=8192
  22 2032+0 records in
  23 2032+0 records out
  24 real    0m 3.09s
  25 user    0m 0.00s
  26 sys     0m 1.56s
  27
  28 Signed-off-by: Jonas Gorski <jogo@openwrt.org>
  29 ---
  30  drivers/spi/spi-bcm63xx-hsspi.c | 13 +++++++++----
  31  1 file changed, 9 insertions(+), 4 deletions(-)
  32
  33 --- a/drivers/spi/spi-bcm63xx-hsspi.c
  34 +++ b/drivers/spi/spi-bcm63xx-hsspi.c
  35 @@ -76,6 +76,7 @@
  36  #define HSSPI_FIFO_REG(x)                      (0x200 + (x) * 0x200)
  37
  38
  39 +#define HSSPI_OP_MULTIBIT                      BIT(11)
  40  #define HSSPI_OP_CODE_SHIFT                    13
  41  #define HSSPI_OP_SLEEP                         (0 << HSSPI_OP_CODE_SHIFT)
  42  #define HSSPI_OP_READ_WRITE                    (1 << HSSPI_OP_CODE_SHIFT)
  43 @@ -171,9 +172,12 @@ static int bcm63xx_hsspi_do_txrx(struct
  44         if (opcode != HSSPI_OP_READ)
  45                 step_size -= HSSPI_OPCODE_LEN;
  46
  47 -       __raw_writel(0 << MODE_CTRL_PREPENDBYTE_CNT_SHIFT |
  48 -                    2 << MODE_CTRL_MULTIDATA_WR_STRT_SHIFT |
  49 -                    2 << MODE_CTRL_MULTIDATA_RD_STRT_SHIFT | 0xff,
  50 +       if ((opcode == HSSPI_OP_READ && t->rx_nbits == SPI_NBITS_DUAL) ||
  51 +           (opcode == HSSPI_OP_WRITE && t->tx_nbits == SPI_NBITS_DUAL))
  52 +               opcode |= HSSPI_OP_MULTIBIT;
  53 +
  54 +       __raw_writel(1 << MODE_CTRL_MULTIDATA_WR_SIZE_SHIFT |
  55 +                    1 << MODE_CTRL_MULTIDATA_RD_SIZE_SHIFT | 0xff,
  56                      bs->regs + HSSPI_PROFILE_MODE_CTRL_REG(chip_select));
  57
  58         while (pending > 0) {
  59 @@ -374,7 +378,8 @@ static int bcm63xx_hsspi_probe(struct pl
  60         master->num_chipselect = 8;
  61         master->setup = bcm63xx_hsspi_setup;
  62         master->transfer_one_message = bcm63xx_hsspi_transfer_one;
  63 -       master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
  64 +       master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH |
  65 +                           SPI_RX_DUAL | SPI_TX_DUAL;
  66         master->bits_per_word_mask = SPI_BPW_MASK(8);
  67         master->auto_runtime_pm = true;
  68