[U-Boot] [PATCH v2] pcm058: fix NAND flash not using badblock table

[Harald Seiler]

Hello Marek,

On Fri, 2018-12-07 at 12:48 +0100, Marek Vasut wrote:
> On 12/07/2018 10:19 AM, Harald Seiler wrote:
> > Currently, U-Boot ignores the BBT stored in the last 4 blocks of NAND
> > flash because the NAND_BBT_USE_FLASH flag is not set.  This leads to
> > two issues:
> > 
> > * U-Boot silently uses a memory-only BBT which is initialized with all
> >   blocks marked as good.  This means, actual bad blocks are marked good
> >   and U-Boot might try writing to or reading from them.
> > * The BBT in flash, which will be created once Linux boots up, is not
> >   off limits for a driver ontop, like UBI.  While it does not seem to
> >   consistently produce an error, sometimes UBI will fail to attach
> >   because the BBT blocks obviously don't contain valid UBI data.
> > 
> > To fix this, this patch sets the CONFIG_SYS_NAND_USE_FLASH_BBT option,
> > which is used in ./drivers/mtd/nand/raw/mxs_nand.c to decide whether
> > a BBT in flash is used.
> > 
> > Signed-off-by: Harald Seiler <hws at denx.de>
> 
> V2 Changelog is missing.
> 
> > ---
> >  include/configs/pcm058.h | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/include/configs/pcm058.h b/include/configs/pcm058.h
> > index 49048c163f..b9bc08b388 100644
> > --- a/include/configs/pcm058.h
> > +++ b/include/configs/pcm058.h
> > @@ -55,6 +55,7 @@
> >  #define CONFIG_SYS_NAND_BASE		0x40000000
> >  #define CONFIG_SYS_NAND_5_ADDR_CYCLE
> >  #define CONFIG_SYS_NAND_ONFI_DETECTION
> > +#define CONFIG_SYS_NAND_USE_FLASH_BBT
> 
> Shouldn't this be enabled on all boards with GPMI NAND ?
> 

I looked at other boards and they all defined this config, so I
assumed this was the way to go ... But yes, as far as I understand,
it would make sense to have it enabled most of the time.  Although
there is some code which makes this configuration from the
devicetree, which might be an even better solution.

> >  #endif
> >  
> >  /* DMA stuff, needed for GPMI/MXS NAND support */
> > 
> 
> 

-- 
Harald

DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-62  Fax: +49-8142-66989-80   Email: hws at denx.de