[PATCH] ARM: Fix Keystone 2 kernel mapping regression

[Russell King (Oracle)]

Hi Linus,

Looks fine. An improvement:

On Wed, Aug 04, 2021 at 03:57:47PM +0200, Linus Walleij wrote:
> @@ -250,7 +253,12 @@ __create_page_tables:
>  	add	r0, r4, #KERNEL_OFFSET >> (SECTION_SHIFT - PMD_ORDER)
>  	ldr	r6, =(_end - 1)
>  	adr_l	r5, kernel_sec_start		@ _pa(kernel_sec_start)
> -	str	r8, [r5]			@ Save physical start of kernel
> +#ifdef CONFIG_CPU_ENDIAN_BE8
> +	add	r5, r5, #4			@ Move to the upper 32bit word
> +	str	r8, [r5]			@ Save physical start of kernel (BE)

These two instructions can simply be replaced with:

	str	r8, [r5, #4]

> +#else
> +	str	r8, [r5]			@ Save physical start of kernel (LE)
> +#endif
>  	orr	r3, r8, r7			@ Add the MMU flags
>  	add	r6, r4, r6, lsr #(SECTION_SHIFT - PMD_ORDER)
>  1:	str	r3, [r0], #1 << PMD_ORDER
> @@ -259,7 +267,12 @@ __create_page_tables:
>  	bls	1b
>  	eor	r3, r3, r7			@ Remove the MMU flags
>  	adr_l	r5, kernel_sec_end		@ _pa(kernel_sec_end)
> -	str	r3, [r5]			@ Save physical end of kernel
> +#ifdef CONFIG_CPU_ENDIAN_BE8
> +	add	r5, r5, #4			@ Move to the upper 32bit word
> +	str	r8, [r5]			@ Save physical end of kernel (BE)

Same here.

The patch can still usefully be tested by Nishanth without these
changes... it'll tell us if this was indeed the issue.

Thanks!

-- 
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