[U-Boot] [PATCH v2 3/7] bootcount: Add function wrappers to handle bootcount increment and error checking

[Stefan Roese]

On 14.03.2018 18:24, Lukasz Majewski wrote:
> Those two functions can be used to provide easy bootcount management.
> 
> Signed-off-by: Lukasz Majewski <lukma at denx.de>
> 
> ---
> 
> Changes in v2:
> - None
> 
>   include/bootcount.h | 25 +++++++++++++++++++++++++
>   1 file changed, 25 insertions(+)
> 
> diff --git a/include/bootcount.h b/include/bootcount.h
> index e3b3f7028e..0ec9af6e2b 100644
> --- a/include/bootcount.h
> +++ b/include/bootcount.h
> @@ -40,4 +40,29 @@ static inline u32 raw_bootcount_load(volatile u32 *addr)
>   	return in_be32(addr);
>   }
>   #endif
> +
> +#ifdef CONFIG_SPL_BOOTCOUNT_LIMIT
> +static inline bool bootcount_error(void)
> +{
> +	unsigned long bootcount = bootcount_load();
> +	unsigned long bootlimit = env_get_ulong("bootlimit", 10, 0);
> +
> +	if (bootlimit && (bootcount > bootlimit)) {
> +		printf("Warning: Bootlimit (%lu) exceeded.\n", bootlimit);
> +		return true;
> +	}
> +
> +	return false;
> +}
> +
> +static inline void bootcount_inc(void)
> +{
> +	unsigned long bootcount = bootcount_load();
> +
> +	bootcount_store(++bootcount);
> +}

Why not:

static inline void bootcount_inc(void)
{
	bootcount_store(bootcount_load() + 1);
}

instead ?

> +#else
> +static inline bool bootcount_error(void) { return false; }
> +static inline void bootcount_inc(void) {}
> +#endif /* CONFIG_SPL_BOOTCOUNT_LIMIT */
>   #endif /* _BOOTCOUNT_H__ */

And can't you use these helper functions in proper U-Boot as well
(common/autoboot.c). Looking at this old code there, there is also
room for improvement - perhaps as a new patch in this series. ;)

Thanks,
Stefan