[PATCH v4 12/14] ARM64: KVM: vgic_elrsr and vgic_eisr need to be byteswapped in BE case

Christoffer Dall christoffer.dall at linaro.org
Sat Jun 14 08:04:59 PDT 2014


On Thu, Jun 12, 2014 at 09:30:11AM -0700, Victor Kamensky wrote:
> On arm64 'u32 vgic_eisr[2];' and 'u32 vgic_elrsr[2]' are accessed as
> one 'unsigned long *' bit fields, which has 64bit size. So we need to
> swap least significant word with most significant word when code reads
> those registers from h/w.
> 
> Signed-off-by: Victor Kamensky <victor.kamensky at linaro.org>
> ---
>  arch/arm64/kvm/hyp.S | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S
> index 0620691..5035b41 100644
> --- a/arch/arm64/kvm/hyp.S
> +++ b/arch/arm64/kvm/hyp.S
> @@ -415,10 +415,17 @@ CPU_BE(	rev	w11, w11 )
>  	str	w4, [x3, #VGIC_CPU_HCR]
>  	str	w5, [x3, #VGIC_CPU_VMCR]
>  	str	w6, [x3, #VGIC_CPU_MISR]
> +#ifndef CONFIG_CPU_BIG_ENDIAN
>  	str	w7, [x3, #VGIC_CPU_EISR]
>  	str	w8, [x3, #(VGIC_CPU_EISR + 4)]
>  	str	w9, [x3, #VGIC_CPU_ELRSR]
>  	str	w10, [x3, #(VGIC_CPU_ELRSR + 4)]
> +#else
> +	str	w7, [x3, #(VGIC_CPU_EISR + 4)]
> +	str	w8, [x3, #VGIC_CPU_EISR]
> +	str	w9, [x3, #(VGIC_CPU_ELRSR + 4)]
> +	str	w10, [x3, #VGIC_CPU_ELRSR]
> +#endif
>  	str	w11, [x3, #VGIC_CPU_APR]
>  
>  	/* Clear GICH_HCR */
> -- 
> 1.8.1.4
> 
I thought Marc had something here which allowed you to deal with the
conversion in the accessor functions and avoid this patch?

-Christoffer



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