[PATCH 3/4] ARM: OMAP2: gpmc: Add support for BCH ECC scheme

Philip, Avinash avinashphilip at ti.com
Tue Oct 23 06:18:02 EDT 2012


On Tue, Oct 16, 2012 at 00:18:30, Peter Korsgaard wrote:
> >>>>> Philip, Avinash <avinashphilip at ti.com> writes:
> 
>  > Add support for BCH ECC scheme to gpmc driver and also enabling multi
>  > sector read/write. This helps in doing single shot NAND page read and
>  > write.
> 
>  > ECC engine configurations
>  > BCH 4 bit support
>  > 1. write => ECC engine configured in wrap mode 6 and with ecc_size0 as 32.
>  > 2. read  => ECC engine configured in wrap mode 1 and with ecc_size0 as
>  > 13 and ecc_size1 as 1.
> 
>  > BCH 8 bit support
>  > 1. write => ECC engine configured in wrap mode 6 and with ecc_size0 as 32.
>  > 2. read  => ECC engine configured in wrap mode 1 and with ecc_size0 as
>  > 26 and ecc_size1 as 2.
> 
>  > Note: For BCH8 ECC bytes set to 14 to make compatible with RBL.
> 
> On what device? In the am335x TRM (spruh73f.pdf) figure 26-15 (pg 4273)
> the rom code is documented to not use any padding on the ECC bytes
> (E.G. oob 2..53):
> 
> http://www.ti.com/litv/pdf/spruh73f
> 
> I see the driver in the u-boot-am33x tree (ti81xx_nand.c) seems to use
> 4x14 bytes as well though, so perhaps that's a bug in the documentation
> instead?

Yes, RBL uses 4x14 bytes.

Thanks
Avinash

> 
> -- 
> Bye, Peter Korsgaard
> 




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