[U-Boot] [PATCH 3/3] powerpc/mpc85xx: SECURE BOOT- Disable law 0 for non PBL platforms

[Scott Wood]

On Mon, 2014-01-20 at 14:57 +0530, Aneesh Bansal wrote:
> ISBC creates a LAW 0 entry for non PBL platforms, which is not
> disabled before transferring the control to uboot.
> The LAW 0 entry has to be disabled.
> 
> Signed-off-by: Aneesh Bansal <aneesh.bansal at freescale.com>
> ---
>  arch/powerpc/cpu/mpc85xx/start.S | 58 ++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 58 insertions(+)
> 
> diff --git a/arch/powerpc/cpu/mpc85xx/start.S b/arch/powerpc/cpu/mpc85xx/start.S
> index 5440bf5..2b2c4dd 100644
> --- a/arch/powerpc/cpu/mpc85xx/start.S
> +++ b/arch/powerpc/cpu/mpc85xx/start.S
> @@ -116,6 +116,64 @@ _start_e500:
>  	mtspr	SPRN_HDBCR0, r3
>  #endif
>  
> +#if defined(CONFIG_SECURE_BOOT) && defined(CONFIG_E500) && \
> +						!defined(CONFIG_E500MC)

CONFIG_E500 can be assumed in this file.

> +	/* ISBC creates a LAW 0 entry for non PBL platforms,
> +	 * which is not disabled before transferring the control to uboot.
> +	 * Disable the LAW 0 entry here.
> +	 */

Could you explain what this LAW 0 entry is for, why we don't need it,
and why we can't wait until later to clear it?

-Scott