target/linux/sunxi/patches-4.1/129-nand-sunxi-fix-write-to-USER_DATA-a13.patch

   1 From b1488f1a55da6a297ac4e8e9140922f35b7583c5 Mon Sep 17 00:00:00 2001
   2 From: Boris Brezillon <boris.brezillon@free-electrons.com>
   3 Date: Mon, 15 Jun 2015 11:09:58 +0200
   4 Subject: [PATCH] nand: sunxi: fix write to USER_DATA reg
   5
   6 The USER_DATA register cannot be updated with readb on A13 SoCs, thus
   7 triggering a bug when using memcpy_toio on this register.
   8 Use writel (plus a temporary variable to old the USER_DATA value) to
   9 address that problem.
  10
  11 Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
  12 ---
  13  drivers/mtd/nand/sunxi_nand.c | 38 +++++++++++++++++++++-----------------
  14  1 file changed, 21 insertions(+), 17 deletions(-)
  15
  16 --- a/drivers/mtd/nand/sunxi_nand.c
  17 +++ b/drivers/mtd/nand/sunxi_nand.c
  18 @@ -908,7 +908,7 @@ static int sunxi_nfc_hw_ecc_write_page(s
  19
  20         for (i = 0; i < ecc->steps; i++) {
  21                 bool rndactiv = false;
  22 -               u8 oob_buf[4];
  23 +               u32 user_data;
  24
  25                 if (i)
  26                         chip->cmdfunc(mtd, NAND_CMD_RNDIN, i * ecc->size, -1);
  27 @@ -919,15 +919,13 @@ static int sunxi_nfc_hw_ecc_write_page(s
  28                 offset = layout->eccpos[i * ecc->bytes] - 4 + mtd->writesize;
  29
  30                 /* Fill OOB data in */
  31 -               if (!oob_required)
  32 -                       memset(oob_buf, 0xff, 4);
  33 -               else
  34 -                       memcpy(oob_buf,
  35 -                              chip->oob_poi + layout->oobfree[i].offset,
  36 -                              4);
  37 -
  38 -
  39 -               memcpy_toio(nfc->regs + NFC_REG_USER_DATA_BASE, oob_buf, 4);
  40 +               if (!oob_required) {
  41 +                       user_data = 0xffffffff;
  42 +               } else {
  43 +                       memcpy(&user_data,
  44 +                              chip->oob_poi + layout->oobfree[i].offset, 4);
  45 +                       user_data = le32_to_cpu(user_data);
  46 +               }
  47
  48                 if (i) {
  49                         cnt = ecc->bytes + 4;
  50 @@ -946,12 +944,16 @@ static int sunxi_nfc_hw_ecc_write_page(s
  51                 if (rndactiv) {
  52                         /* pre randomize to generate FF patterns on the NAND */
  53                         if (!i) {
  54 +                               u8 oob_tmp[2];
  55                                 u16 state = rnd->subseeds[rnd->page % rnd->nseeds];
  56 +                               oob_tmp[0] = user_data;
  57 +                               oob_tmp[1] = user_data >> 8;
  58                                 state = sunxi_nfc_hwrnd_single_step(state, 15);
  59 -                               oob_buf[0] ^= state;
  60 +                               oob_tmp[0] ^= state;
  61                                 state = sunxi_nfc_hwrnd_step(rnd, state, 1);
  62 -                               oob_buf[1] ^= state;
  63 -                               memcpy_toio(nfc->regs + NFC_REG_USER_DATA_BASE, oob_buf, 4);
  64 +                               oob_tmp[1] ^= state;
  65 +                               user_data &= ~0xffff;
  66 +                               user_data |= oob_tmp[0] | (oob_tmp[1] << 8);
  67                         }
  68                         tmp = readl(nfc->regs + NFC_REG_ECC_CTL);
  69                         tmp &= ~(NFC_RANDOM_DIRECTION | NFC_ECC_EXCEPTION);
  70 @@ -959,6 +961,8 @@ static int sunxi_nfc_hw_ecc_write_page(s
  71                         writel(tmp, nfc->regs + NFC_REG_ECC_CTL);
  72                 }
  73
  74 +               writel(user_data, nfc->regs + NFC_REG_USER_DATA_BASE);
  75 +
  76                 chip->cmdfunc(mtd, NAND_CMD_RNDIN, offset, -1);
  77
  78                 ret = sunxi_nfc_wait_cmd_fifo_empty(nfc);