[U-Boot] [PATCH v5 02/18] rockchip: boot0: align to 0x20 for armv7 '_start'

[Andy Yan]

Hi Phipipp, Kever:


On 2017年10月10日 22:21, Philipp Tomsich wrote:
> From: Kever Yang <kever.yang at rock-chips.com>
>
> The '_start' is using as vector table base address, and will write
> to VBAR register, so it needs to be aligned to 0x20 for armv7.
>
> Signed-off-by: Kever Yang <kever.yang at rock-chips.com>
> [Updated to current code base:]
> Signed-off-by: Philipp Tomsich <philipp.tomsich at theobroma-systems.com>
>
> ---
>
> Changes in v5: None
> Changes in v4: None
> Changes in v3: None
> Changes in v2: None
>
>   arch/arm/include/asm/arch-rockchip/boot0.h | 14 ++++++++++++--
>   1 file changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm/include/asm/arch-rockchip/boot0.h b/arch/arm/include/asm/arch-rockchip/boot0.h
> index 455d842..f7c6146 100644
> --- a/arch/arm/include/asm/arch-rockchip/boot0.h
> +++ b/arch/arm/include/asm/arch-rockchip/boot0.h
> @@ -6,12 +6,13 @@
>   
>   /*
>    * Execution starts on the instruction following this 4-byte header
> - * (containing the magic 'RK33').
> + * (containing the magic 'RK30', 'RK31', 'RK32' or 'RK33').  This
> + * magic constant will be written into the final image by the rkimage
> + * tool, but we need to reserve space for it here.
>    *
>    * To make life easier for everyone, we build the SPL binary with
>    * space for this 4-byte header already included in the binary.
>    */
> -
>   #ifdef CONFIG_SPL_BUILD
>   	/*
>   	 * We need to add 4 bytes of space for the 'RK33' at the
> @@ -26,6 +27,15 @@
>   	b reset	 /* may be overwritten --- should be 'nop' or a 'b reset' */
>   #endif
>   	b reset

     Do we really need the "b reset" here? the macro ARM_VECTORS already 
has a b reset.
Besides Joseph found  that the irq function will not work with this "b 
reset"
> +#if !defined(CONFIG_ARM64)
> +	/*
> +	 * For armv7, the addr '_start' will used as vector start address
> +	 * and write to VBAR register, which needs to aligned to 0x20.
> +	 */
> +	.align(5)
> +_start:
> +	ARM_VECTORS
> +#endif
>   
>   #if defined(CONFIG_ROCKCHIP_RK3399) && defined(CONFIG_SPL_BUILD)
>   	.space CONFIG_ROCKCHIP_SPL_RESERVE_IRAM	/* space for the ATF data */