[U-Boot] [PATCH 2/2] arm: Fix _start for CONFIG_SYS_DV_NOR_BOOT_CFG

[Albert ARIBAUD]

Hi Benoît,

On Wed,  3 Sep 2014 23:32:34 +0200, Benoît Thébaudeau
<benoit.thebaudeau.dev at gmail.com> wrote:

> The boards using CONFIG_SYS_DV_NOR_BOOT_CFG (i.e. calimain,
> da850evm_direct_nor and enbw_cmc) had the _start symbol defined after
> the CONFIG_SYS_DV_NOR_BOOT_CFG word rather than before it in
> arch/arm/lib/vectors.S. Because of that, if by lack of luck
> 'gd->mon_len = (ulong)&__bss_end - (ulong)_start' (see setup_mon_len())
> was a multiple of 4 kiB (see reserve_uboot()), then the last BSS word
> overlapped the first word of the following reserved RAM area (or went
> beyond the top of RAM without such an area) after relocation because
> __image_copy_start did not match _start (see relocate_code()).
> 
> This was broken by commit 41623c9 'arm: move exception handling out of
> start.S files', which defined _start twice (before and after the
> CONFIG_SYS_DV_NOR_BOOT_CFG word), then by commit 0a26e1d 'arm: fix a
> double-definition error of _start symbol', which kept the definition of
> the _start symbol after the CONFIG_SYS_DV_NOR_BOOT_CFG word. This new
> commit fixes this issue by restoring the original behavior, i.e. by
> defining the _start symbol before the CONFIG_SYS_DV_NOR_BOOT_CFG word.
> 
> Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau.dev at gmail.com>
> Cc: Albert Aribaud <albert.u.boot at aribaud.net>
> Cc: Manfred Rudigier <manfred.rudigier at omicron.at>
> Cc: Christian Riesch <christian.riesch at omicron.at>
> Cc: Sudhakar Rajashekhara <sudhakar.raj at ti.com>
> Cc: Heiko Schocher <hs at denx.de>
> ---
>  arch/arm/lib/vectors.S |    3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm/lib/vectors.S b/arch/arm/lib/vectors.S
> index 843b18f..0cb87ce 100644
> --- a/arch/arm/lib/vectors.S
> +++ b/arch/arm/lib/vectors.S
> @@ -45,11 +45,12 @@
>   *************************************************************************
>   */
>  
> +_start:
> +
>  #ifdef CONFIG_SYS_DV_NOR_BOOT_CFG
>  	.word	CONFIG_SYS_DV_NOR_BOOT_CFG
>  #endif
>  
> -_start:
>  	b	reset
>  	ldr	pc, _undefined_instruction
>  	ldr	pc, _software_interrupt

Applied (as a bug fix) to u-boot-arm/master, thanks!

Amicalement,
-- 
Albert.