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

[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?

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
> 
> 

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