[U-Boot] [PATCH] [v4] powerpc/85xx: fix compatible property for the L2 cache node

[Wolfgang Denk]

Dear Timur Tabi,

In message <1304113875-6749-1-git-send-email-timur at freescale.com> you wrote:
> The compatible property for the L2 cache node (on 85xx systems that don't
> have a CPC) was using a value for the property length that did not match
> the actual length of the property.
> 
> Signed-off-by: Timur Tabi <timur at freescale.com>
> ---
>  arch/powerpc/cpu/mpc85xx/fdt.c |   20 ++++++++++++--------
>  1 files changed, 12 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/powerpc/cpu/mpc85xx/fdt.c b/arch/powerpc/cpu/mpc85xx/fdt.c
> index 642f6c5..121db5f 100644
> --- a/arch/powerpc/cpu/mpc85xx/fdt.c
> +++ b/arch/powerpc/cpu/mpc85xx/fdt.c
> @@ -165,7 +165,6 @@ static inline void ft_fixup_l2cache(void *blob)
>  	int len, off;
>  	u32 *ph;
>  	struct cpu_type *cpu = identify_cpu(SVR_SOC_VER(get_svr()));
> -	char compat_buf[38];
>  
>  	const u32 line_size = 32;
>  	const u32 num_ways = 8;
> @@ -192,22 +191,27 @@ static inline void ft_fixup_l2cache(void *blob)
>  	}
>  
>  	if (cpu) {
> +		char buf[40];
> +
>  		if (isdigit(cpu->name[0]))
> -			len = sprintf(compat_buf,
> -				"fsl,mpc%s-l2-cache-controller", cpu->name);
> +			/* MPCxxxx, where xxxx == 4-digit number */
> +			len = sprintf(buf, "fsl,mpc%s-l2-cache-controller",
> +				cpu->name) + 1;
>  		else
> -			len = sprintf(compat_buf,
> -				"fsl,%c%s-l2-cache-controller",
> -				tolower(cpu->name[0]), cpu->name + 1);
> +			/* Pxxxx or Txxxx, where xxxx == 4-digit number */
> +			len = sprintf(buf, "fsl,%c%s-l2-cache-controller",
> +				tolower(cpu->name[0]), cpu->name + 1) + 1;

Why do we need this "if" at all? tolower() on a digit is a nop, so you
can omit the first branch.

> +		/* append "cache" to the string */
> +		len += sprintf(buf + len, "cache") + 1;

This is wrong and misleading.  This is not an operation on a C string.
You do not "append" (or concatenate) the string cache.  You build a
specifically structured data set, which is not a C string.  So please
don't call it a string.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Speculation is always more interesting than facts.
                                    - Terry Pratchett, _Making_Money_