[U-Boot] PATCH mtd CFI flash: timeout calculation underflow if imprecise 1kHz timer: fix

[Wolfgang Denk]

Dear Renato Andreola,

In message <4A7AD624.9030902 at imagos.it> you wrote:
>  From 3723c8437d8c3d2e04bc3bc1de9c21b33072ab08 Mon Sep 17 00:00:00 2001
> From: Renato Andreola <renato.andreola at imagos.it>
> Date: Thu, 6 Aug 2009 14:49:59 +0200
> Subject: [PATCH] drivers/mtd/cfi_flash: precision and underflow problem 
> in tout calculation
> 
> With old configuration it could happen tout=0 if CONFIG_SYS_HZ<1000
> solved avoiding the preprocessor conditional and introducing a compile 
> time branch between a high freq case and a slow freq case.
> 
> Signed-off-by: Renato Andreola renato.andreola at imagos.it
> ---
>   drivers/mtd/cfi_flash.c |    7 ++++---
>   1 files changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c
> index 81ac5d3..b118f71 100644
> --- a/drivers/mtd/cfi_flash.c
> +++ b/drivers/mtd/cfi_flash.c
> @@ -659,9 +659,10 @@ static int flash_status_check (flash_info_t * info, 
> flash_sect_t sector,
>   {
>   	ulong start;
> 
> -#if CONFIG_SYS_HZ != 1000
> -	tout *= CONFIG_SYS_HZ/1000;
> -#endif
> +        if (CONFIG_SYS_HZ > 10000)
> +                tout *= CONFIG_SYS_HZ/1000;  /* for a big HZ, avoid 
> overflow */
> +        else
> +                tout = tout * CONFIG_SYS_HZ / 1000 + 1;

NAK, for several reasons:

1) The patch is line wrapped and thus unusable.
2) There should be a Signed-off-by: from Alessandro, too.
3) Please use TAB only for indentation.
4) Please use parens to show what you are relying on, i. e.

	tout = (tout * CONFIG_SYS_HZ) / 1000;

5) Omit the "+1". It seems bogus to me.

Best regards,

Wolfgang Denk

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