Re: Au1550 Nandflash

[Manuel Lauss <mano@roarinelk.homelinux.net>]

On Thu, 7 Aug 2008 12:16:19 +0800
"maowy" <maowy@avit.org.cn> wrote:

> borasah____________
>       I have the same problem with you when using nandflash.
>     Our kernel can recognize nandflash but it seems to be all bad block.
>       How dou you successfully solve this problem of  nandflash .
>       Can you tell how to solve this problem.
>       Hope to receive your letter as soon as possible.Thanks.
>       
> 
> our platform:AU1550
> OS:linux-2.6.13

Please give the "gen_nand" driver a try.  I ran into identical problems
on Au1200; the in-kernel au1550nd.c code seems to be explicitly
tailored for small-page nands on the PB1550/DB1200 boards and doesn't
seem to work anywhere else.

FWIW, here's a snippet I use on Au1200 which you can paste into your
board setup code; it should work on Au1550 too since the NAND parts are
identical.

---------- 8< --------------------- 8< -----------------

#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <asm/mach-au1x00/au1000.h>

static void au1200_nand_cmd_ctrl(struct mtd_info *mtd, int cmd,
                                 unsigned int ctrl)
{
        struct nand_chip *this = mtd->priv;
        unsigned long ioaddr = (unsigned long)this->IO_ADDR_W;

        ioaddr &= 0xffffff00;

        if (ctrl & NAND_CLE) {
                ioaddr += MEM_STNAND_CMD;
        } else if (ctrl & NAND_ALE) {
                ioaddr += MEM_STNAND_ADDR;
        } else {
                /* assume we want to r/w real data  by default */
                ioaddr += MEM_STNAND_DATA;
        }
        this->IO_ADDR_R = this->IO_ADDR_W = (void __iomem *)ioaddr;
        if (cmd != NAND_CMD_NONE) {
                au_writeb(cmd, ioaddr);
                au_sync();
        }
}

static int au1200_nand_device_ready(struct mtd_info *mtd)
{
        int ret = (au_readl(MEM_STSTAT) & 1);
        au_sync();
        return ret;
}

static const char *au1200_part_probes[] = { "cmdlinepart", NULL };

static struct mtd_partition au1200_nand_parts[] = {
        [0] = {
                .name   = "NAND FS 0",
                .offset = 0,
                .size   = MTDPART_SIZ_FULL,
        },
};

struct platform_nand_data au1200_nand_platdata = {
        .chip = {
                .nr_chips = 1,
                .chip_offset = 0,
                .nr_partitions = ARRAY_SIZE(au1200_nand_parts),
                .partitions = au1200_nand_parts,
                .chip_delay = 20,
                .part_probe_types = au1200_part_probes,
        },
        .ctrl = {
                .hwcontrol = 0,
                .dev_ready = au1200_nand_device_ready,
                .select_chip = 0,
                .cmd_ctrl = au1200_nand_cmd_ctrl,
        },
};

static struct resource au1200_nand_res[] = {
        [0] = {
                .start = 0x20000000,
                .end   = 0x200000ff,
                .flags = IORESOURCE_MEM,
        },
};

static struct platform_device au1200_nand_dev = {
        .name           = "gen_nand",
        .num_resources  = ARRAY_SIZE(au1200_nand_res),
        .resource       = au1200_nand_res,
        .id             = -1,
        .dev            = {
                .platform_data = &au1200_nand_platdata,
        }
};

---------- 8< --------------------- 8< -----------------


Best regards,
        Manuel Lauss