[U-Boot] [PATCH 3/4] atmel_nand: increase more delay to support MT29F32G08CBADA

[Yang, Wenyou]

Hi Andreas,

> -----Original Message-----
> From: Andreas Bießmann [mailto:andreas.devel at googlemail.com]
> Sent: 2016年1月25日 5:42
> To: Wu, Josh <Josh.wu at atmel.com>; Scott Wood <scottwood at freescale.com>;
> U-Boot Mailing List <u-boot at lists.denx.de>
> Cc: Yang, Wenyou <Wenyou.Yang at atmel.com>; Bo Shen
> <voice.shen at gmail.com>
> Subject: Re: [PATCH 3/4] atmel_nand: increase more delay to support
> MT29F32G08CBADA
> 
> Hi Josh,
> 
> On 24.11.15 09:26, Josh Wu wrote:
> > The tR is 100us in the datasheet section: Array Characteristics
> >
> 
> I've seen 50us for tR. Which datasheet do you have?

The datasheet is downloaded from micron official website.

https://www.micron.com/parts/nand-flash/mass-storage/mt29f32g08cbadawp?pc=%7B80EFFAAD-26CB-4D06-84BC-0E3274B960A9%7D

This device requires the number of bits ECC correctability is 40 bits,

but the maximum error correction capability of PMECC IP of SAMA5D2 is 32 bits.

That is,  SAMA5D2 can't support this device.

So, I suggest to drop this patch.

> 
> Andreas
> 
> > Signed-off-by: Josh Wu <josh.wu at atmel.com>
> > ---
> >
> >  drivers/mtd/nand/atmel_nand.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/mtd/nand/atmel_nand.c
> > b/drivers/mtd/nand/atmel_nand.c index 5226acf..266dfd9 100644
> > --- a/drivers/mtd/nand/atmel_nand.c
> > +++ b/drivers/mtd/nand/atmel_nand.c
> > @@ -1492,7 +1492,7 @@ int atmel_nand_chip_init(int devnum, ulong
> > base_addr)  #ifdef CONFIG_SYS_NAND_READY_PIN
> >  	nand->dev_ready = at91_nand_ready;
> >  #endif
> > -	nand->chip_delay = 75;
> > +	nand->chip_delay = 100;
> >  #ifdef CONFIG_SYS_NAND_USE_FLASH_BBT
> >  	nand->bbt_options |= NAND_BBT_USE_FLASH;  #endif
> >

Best Regards,
Wenyou Yang