[PATCH 08/12] cfi flash: fix flash_make_cmd for big endian access

[Sascha Hauer]

On Fri, Sep 23, 2011 at 04:05:29PM +0200, Teresa Gamez wrote:
> Hello Sascha,
> 
> Am Freitag, den 23.09.2011, 11:26 +0200 schrieb Sascha Hauer:
> > Hi Teresa,
> > 
> > On Fri, Sep 23, 2011 at 11:24:16AM +0200, Sascha Hauer wrote:
> > > This is broken on big endian systems since:
> > > 
> > > 943b271 cfi_flash: support of u32 cmd
> > > 
> > > I looked over it and I *think* that the function was correct
> > > for both big and little endian systems before this patch.
> > > To support u32 cmd we only have to change the data type of
> > > the command from u8 to u32.
> > 
> > Can you please test if this patch works on your u8-is-not-enough
> > flash?
> 
> Successfully tested with a u8-is-not-enough flash (28F256P33BF) on a
> phyCORE-i.MX35.

Nice, thanks. I can't test this with such a flash on a big endian
machine, but I'm confident that the patch does the right thing.
Famous last words...

Sascha


> 
> Teresa
> 
> > 
> > Sascha
> > 
> > > 
> > > Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> > > Cc: Teresa Gámez <t.gamez at phytec.de>
> > > ---
> > >  drivers/nor/cfi_flash.c |   24 +++++-------------------
> > >  1 files changed, 5 insertions(+), 19 deletions(-)
> > > 
> > > diff --git a/drivers/nor/cfi_flash.c b/drivers/nor/cfi_flash.c
> > > index f9b96c5..654e647 100644
> > > --- a/drivers/nor/cfi_flash.c
> > > +++ b/drivers/nor/cfi_flash.c
> > > @@ -822,26 +822,12 @@ int flash_generic_status_check (struct flash_info *info, flash_sect_t sector,
> > >   */
> > >  void flash_make_cmd(struct flash_info *info, u32 cmd, cfiword_t *cmdbuf)
> > >  {
> > > -	int i;
> > > -	int cp_offset;
> > > -	int cword_offset;
> > > -	uchar val;
> > > -	uchar *cp;
> > > -
> > > -	*cmdbuf = 0;
> > > -	cp = (uchar *)cmdbuf;
> > > +	cfiword_t result = 0;
> > > +	int i = info->portwidth / info->chipwidth;
> > >  
> > > -	for (i = info->portwidth; i > 0; i--) {
> > > -		cword_offset = (info->portwidth-i) % info->chipwidth;
> > > -#if __BYTE_ORDER == __LITTLE_ENDIAN
> > > -		cp_offset = info->portwidth - i;
> > > -		val = *((uchar *)&cmd + cword_offset);
> > > -#else
> > > -		cp_offset = i - 1;
> > > -		val = *((uchar *)&cmd + sizeof(u32) - cword_offset - 1);
> > > -#endif
> > > -	cp[cp_offset] = (cword_offset >= sizeof(u32)) ? 0x00 : val;
> > > -	}
> > > +	while (i--)
> > > +		result = (result << (8 * info->chipwidth)) | cmd;
> > > +	*cmdbuf = result;
> > >  }
> > >  
> > >  /*
> > > -- 
> > > 1.7.6.3
> > > 
> > > 
> > 
> 
> 
> 

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |