[PATCH] mtd: gpmi: add NAND write verify support

[Huang Shijie]

On Fri, Aug 10, 2012 at 7:25 AM, Marek Vasut <marex at denx.de> wrote:
> Dear Huang Shijie,
>
>> Add NAND write verify support in gpmi-nand driver.
>>
>> Signed-off-by: Huang Shijie <b32955 at freescale.com>
>> ---
>>  drivers/mtd/nand/gpmi-nand/gpmi-nand.c |   17 +++++++++++++++++
>>  1 files changed, 17 insertions(+), 0 deletions(-)
>>
>> diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
>> b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c index 8c0d2f0..6394483 100644
>> --- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
>> +++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
>> @@ -1488,6 +1488,22 @@ static int gpmi_set_geometry(struct gpmi_nand_data
>> *this) return gpmi_alloc_dma_buffer(this);
>>  }
>>
>> +#define MAX_PAGESIZE 8192
>
> Use NAND_MAX_PAGESIZE, see include/linux/mtd/nand.h .
>
>> +static uint8_t verify_buf[MAX_PAGESIZE];

ok, thanks.

>
> What will happen when you have two NANDs attached to GPMI controller and they
> hit this place both at once? Race condition, causing this function to fail for
> both?
>
Even there are two nand chips, there is only one gpmi controller.
And the current gpmi-nand does not support two nands now.
does the race occur with only one nand chip?


> Possibly devm_kmalloc() such buffer per-controller?
>
>> +static int gpmi_verify_buf(struct mtd_info *mtd, const uint8_t *buf, int
>> len) +{
>> +     struct nand_chip *nand = mtd->priv;
>> +     int ret;
>> +
>> +     ret = gpmi_ecc_read_page(mtd, nand, verify_buf, 0, 0);
>
> mtd->chip.ecc.read_page() ?
In actually, they are the same.


Best Regards
Huang Shijie