target/linux/lantiq/patches-3.9/0014-MTD-lantiq-xway-make-nand-actually-work.patch

   1 From 48b06753494e3abbf97ffebe02b1765edab7c689 Mon Sep 17 00:00:00 2001
   2 From: John Crispin <blogic@openwrt.org>
   3 Date: Mon, 22 Oct 2012 10:25:39 +0200
   4 Subject: [PATCH 14/22] MTD: lantiq: xway: make nand actually work
   5
   6 http://lists.infradead.org/pipermail/linux-mtd/2012-September/044240.html
   7
   8 Signed-off-by: John Crispin <blogic@openwrt.org>
   9 ---
  10  drivers/mtd/nand/xway_nand.c |   54 +++++++++++++++++++++++++++++++++++-------
  11  1 file changed, 45 insertions(+), 9 deletions(-)
  12
  13 --- a/drivers/mtd/nand/xway_nand.c
  14 +++ b/drivers/mtd/nand/xway_nand.c
  15 @@ -54,19 +54,29 @@
  16  #define NAND_CON_CSMUX         (1 << 1)
  17  #define NAND_CON_NANDM         1
  18
  19 +static u32 xway_latchcmd;
  20 +
  21  static void xway_reset_chip(struct nand_chip *chip)
  22  {
  23         unsigned long nandaddr = (unsigned long) chip->IO_ADDR_W;
  24         unsigned long flags;
  25 +       unsigned long timeout;
  26
  27         nandaddr &= ~NAND_WRITE_ADDR;
  28         nandaddr |= NAND_WRITE_CMD;
  29
  30         /* finish with a reset */
  31 +       timeout = jiffies + msecs_to_jiffies(200);
  32 +
  33         spin_lock_irqsave(&ebu_lock, flags);
  34 +
  35         writeb(NAND_WRITE_CMD_RESET, (void __iomem *) nandaddr);
  36 -       while ((ltq_ebu_r32(EBU_NAND_WAIT) & NAND_WAIT_WR_C) == 0)
  37 -               ;
  38 +       do {
  39 +               if ((ltq_ebu_r32(EBU_NAND_WAIT) & NAND_WAIT_WR_C) == 0)
  40 +                       break;
  41 +               cond_resched();
  42 +       } while (!time_after_eq(jiffies, timeout));
  43 +
  44         spin_unlock_irqrestore(&ebu_lock, flags);
  45  }
  46
  47 @@ -94,17 +104,15 @@ static void xway_cmd_ctrl(struct mtd_inf
  48         unsigned long flags;
  49
  50         if (ctrl & NAND_CTRL_CHANGE) {
  51 -               nandaddr &= ~(NAND_WRITE_CMD | NAND_WRITE_ADDR);
  52                 if (ctrl & NAND_CLE)
  53 -                       nandaddr |= NAND_WRITE_CMD;
  54 -               else
  55 -                       nandaddr |= NAND_WRITE_ADDR;
  56 -               this->IO_ADDR_W = (void __iomem *) nandaddr;
  57 +                       xway_latchcmd = NAND_WRITE_CMD;
  58 +               else if (ctrl & NAND_ALE)
  59 +                       xway_latchcmd = NAND_WRITE_ADDR;
  60         }
  61
  62         if (cmd != NAND_CMD_NONE) {
  63                 spin_lock_irqsave(&ebu_lock, flags);
  64 -               writeb(cmd, this->IO_ADDR_W);
  65 +               writeb(cmd, (void __iomem *) (nandaddr | xway_latchcmd));
  66                 while ((ltq_ebu_r32(EBU_NAND_WAIT) & NAND_WAIT_WR_C) == 0)
  67                         ;
  68                 spin_unlock_irqrestore(&ebu_lock, flags);
  69 @@ -124,12 +132,38 @@ static unsigned char xway_read_byte(stru
  70         int ret;
  71
  72         spin_lock_irqsave(&ebu_lock, flags);
  73 -       ret = ltq_r8((void __iomem *)(nandaddr + NAND_READ_DATA));
  74 +       ret = ltq_r8((void __iomem *)(nandaddr | NAND_READ_DATA));
  75         spin_unlock_irqrestore(&ebu_lock, flags);
  76
  77         return ret;
  78  }
  79
  80 +static void xway_read_buf(struct mtd_info *mtd, u_char *buf, int len)
  81 +{
  82 +       struct nand_chip *this = mtd->priv;
  83 +       unsigned long nandaddr = (unsigned long) this->IO_ADDR_R;
  84 +       unsigned long flags;
  85 +       int i;
  86 +
  87 +       spin_lock_irqsave(&ebu_lock, flags);
  88 +       for (i = 0; i < len; i++)
  89 +               buf[i] = ltq_r8((void __iomem *)(nandaddr | NAND_READ_DATA));
  90 +       spin_unlock_irqrestore(&ebu_lock, flags);
  91 +}
  92 +
  93 +static void xway_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
  94 +{
  95 +       struct nand_chip *this = mtd->priv;
  96 +       unsigned long nandaddr = (unsigned long) this->IO_ADDR_W;
  97 +       unsigned long flags;
  98 +       int i;
  99 +
 100 +       spin_lock_irqsave(&ebu_lock, flags);
 101 +       for (i = 0; i < len; i++)
 102 +               ltq_w8(buf[i], (void __iomem *)nandaddr);
 103 +       spin_unlock_irqrestore(&ebu_lock, flags);
 104 +}
 105 +
 106  static int xway_nand_probe(struct platform_device *pdev)
 107  {
 108         struct nand_chip *this = platform_get_drvdata(pdev);
 109 @@ -175,6 +209,8 @@ static struct platform_nand_data xway_na
 110                 .dev_ready      = xway_dev_ready,
 111                 .select_chip    = xway_select_chip,
 112                 .read_byte      = xway_read_byte,
 113 +               .read_buf       = xway_read_buf,
 114 +               .write_buf      = xway_write_buf,
 115         }
 116  };
 117