[U-Boot] [PATCH] NAND: Let NAND_NO_SUBPAGE_WRITE through

[Marek Vasut <marek.vasut@gmail.com>]

> On Thu, Nov 10, 2011 at 06:02:36PM +0100, Marek Vasut wrote:
> > > There is a problem reported that the NAND_NO_SUBPAGE_WRITE, set by some
> > > drivers, is silently ignored by NAND core. This causes UBI to
> > > malfunction on these drivers, because UBI tries to use subpage writes.
> > > 
> > > This was discussed already with no conclusion, see thread:
> > > Message-Id: <1302372335-30232-6-git-send-email-sbabic@denx.de>
> > > 
> > > The bug was recently retriggered by Veli-Pekka Peltola, causing him
> > > trouble with UBI on the MX28 CPU:
> > > Message-ID: <4EB3E4EA.9080509@bluegiga.com>
> > > 
> > > Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
> > > Cc: Stefano Babic <sbabic@denx.de>
> > > Cc: Scott Wood <scottwood@freescale.com>
> > > Cc: Veli-Pekka Peltola <veli-pekka.peltola@bluegiga.com>
> > > ---
> > > 
> > >  drivers/mtd/nand/nand_base.c |   11 +++++++++++
> > >  1 files changed, 11 insertions(+), 0 deletions(-)
> > > 
> > > diff --git a/drivers/mtd/nand/nand_base.c
> > > b/drivers/mtd/nand/nand_base.c index 6aac6a2..7ecd5a3 100644
> > > --- a/drivers/mtd/nand/nand_base.c
> > > +++ b/drivers/mtd/nand/nand_base.c
> > > @@ -2548,6 +2548,7 @@ static const struct nand_flash_dev
> > > *nand_get_flash_type(struct mtd_info *mtd, {
> > > 
> > >  	int ret, maf_idx;
> > >  	int tmp_id, tmp_manf;
> > > 
> > > +	int no_subpage = 0;
> > > 
> > >  	/* Select the device */
> > >  	chip->select_chip(mtd, 0);
> > > 
> > > @@ -2612,10 +2613,20 @@ static const struct nand_flash_dev
> > > *nand_get_flash_type(struct mtd_info *mtd, if (!ret)
> > > 
> > >  		nand_flash_detect_non_onfi(mtd, chip, type, &busw);
> > > 
> > > +	/*
> > > +	 * If the controller is incapable of subpage writes, force no subpage
> > > +	 * writes. This has to be done here, otherwise UBI will complain.
> > > +	 */
> > > +	if (chip->options & NAND_NO_SUBPAGE_WRITE)
> > > +		no_subpage = 1;
> > > +
> > > 
> > >  	/* Get chip options, preserve non chip based options */
> > >  	chip->options &= ~NAND_CHIPOPTIONS_MSK;
> > >  	chip->options |= type->options & NAND_CHIPOPTIONS_MSK;
> > > 
> > > +	if (no_subpage)
> > > +		chip->options |= NAND_NO_SUBPAGE_WRITE;
> > > +
> > > 
> > >  	/*
> > >  	
> > >  	 * Set chip as a default. Board drivers can override it, if necessary
> > >  	 */
> > 
> > Scott, ping ?
> 
> We could do that I guess, but couldn't we also just get rid of
> NAND_CHIPOPTIONS_MSK?
> 
> -Scott

Actually, maybe we should fix this in Linux first. Is the GPMI-NAND driver for 
i.MX28 applied already to mainline linux-mtd?