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 diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
  17 index 72ab770..3668197 100644
  18 --- a/drivers/mtd/nand/sunxi_nand.c
  19 +++ b/drivers/mtd/nand/sunxi_nand.c
  20 @@ -904,7 +904,7 @@ static int sunxi_nfc_hw_ecc_write_page(struct mtd_info *mtd,
  21
  22         for (i = 0; i < ecc->steps; i++) {
  23                 bool rndactiv = false;
  24 -               u8 oob_buf[4];
  25 +               u32 user_data;
  26
  27                 if (i)
  28                         chip->cmdfunc(mtd, NAND_CMD_RNDIN, i * ecc->size, -1);
  29 @@ -915,15 +915,13 @@ static int sunxi_nfc_hw_ecc_write_page(struct mtd_info *mtd,
  30                 offset = layout->eccpos[i * ecc->bytes] - 4 + mtd->writesize;
  31
  32                 /* Fill OOB data in */
  33 -               if (!oob_required)
  34 -                       memset(oob_buf, 0xff, 4);
  35 -               else
  36 -                       memcpy(oob_buf,
  37 -                              chip->oob_poi + layout->oobfree[i].offset,
  38 -                              4);
  39 -
  40 -
  41 -               memcpy_toio(nfc->regs + NFC_REG_USER_DATA_BASE, oob_buf, 4);
  42 +               if (!oob_required) {
  43 +                       user_data = 0xffffffff;
  44 +               } else {
  45 +                       memcpy(&user_data,
  46 +                              chip->oob_poi + layout->oobfree[i].offset, 4);
  47 +                       user_data = le32_to_cpu(user_data);
  48 +               }
  49
  50                 if (i) {
  51                         cnt = ecc->bytes + 4;
  52 @@ -942,12 +940,16 @@ static int sunxi_nfc_hw_ecc_write_page(struct mtd_info *mtd,
  53                 if (rndactiv) {
  54                         /* pre randomize to generate FF patterns on the NAND */
  55                         if (!i) {
  56 +                               u8 oob_tmp[2];
  57                                 u16 state = rnd->subseeds[rnd->page % rnd->nseeds];
  58 +                               oob_tmp[0] = user_data;
  59 +                               oob_tmp[1] = user_data >> 8;
  60                                 state = sunxi_nfc_hwrnd_single_step(state, 15);
  61 -                               oob_buf[0] ^= state;
  62 +                               oob_tmp[0] ^= state;
  63                                 state = sunxi_nfc_hwrnd_step(rnd, state, 1);
  64 -                               oob_buf[1] ^= state;
  65 -                               memcpy_toio(nfc->regs + NFC_REG_USER_DATA_BASE, oob_buf, 4);
  66 +                               oob_tmp[1] ^= state;
  67 +                               user_data &= ~0xffff;
  68 +                               user_data |= oob_tmp[0] | (oob_tmp[1] << 8);
  69                         }
  70                         tmp = readl(nfc->regs + NFC_REG_ECC_CTL);
  71                         tmp &= ~(NFC_RANDOM_DIRECTION | NFC_ECC_EXCEPTION);
  72 @@ -955,6 +957,8 @@ static int sunxi_nfc_hw_ecc_write_page(struct mtd_info *mtd,
  73                         writel(tmp, nfc->regs + NFC_REG_ECC_CTL);
  74                 }
  75
  76 +               writel(user_data, nfc->regs + NFC_REG_USER_DATA_BASE);
  77 +
  78                 chip->cmdfunc(mtd, NAND_CMD_RNDIN, offset, -1);
  79
  80                 ret = sunxi_nfc_wait_cmd_fifo_empty(nfc);
  81 @@ -1164,13 +1168,13 @@ static int sunxi_nfc_hw_syndrome_ecc_write_page(struct mtd_info *mtd,
  82                 /* Fill OOB data in */
  83                 if (oob_required) {
  84                         tmp = 0xffffffff;
  85 -                       memcpy_toio(nfc->regs + NFC_REG_USER_DATA_BASE, &tmp,
  86 -                                   4);
  87                 } else {
  88 -                       memcpy_toio(nfc->regs + NFC_REG_USER_DATA_BASE, oob,
  89 -                                   4);
  90 +                       memcpy(&tmp, oob, sizeof(tmp));
  91 +                       tmp = le32_to_cpu(tmp);
  92                 }
  93
  94 +               writel(tmp, nfc->regs + NFC_REG_USER_DATA_BASE);
  95 +
  96                 cnt = ecc->bytes + 4;
  97                 if (rnd &&
  98                     nand_rnd_is_activ(mtd, rnd->page, offset, &cnt) > 0 &&