On 30/05/2025 22:31, Mykola Kvach wrote:
> From: Mykola Kvach <mykola_kv...@epam.com>
>
> Add missing input register descriptions to enable_secondary_cpu_mm
> and enable_boot_cpu_mm functions.
>
> Specifically:
> - x19 is used in enable_boot_cpu_mm as physical start address.
> - x20 is used in both functions for physical offset passed to load_paddr.
I'm not sure if we need to document register usage that is part of a comment in
so called "Common register usage". It's repeating information for me. That said,
I can see that Arm32 does that too so no objection.
>
> This update improves code clarity and consistency in comments.
>
> No functional changes are introduced by this patch.
>
> Signed-off-by: Mykola Kvach <mykola_kv...@epam.com>
> ---
> xen/arch/arm/arm64/mmu/head.S | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/xen/arch/arm/arm64/mmu/head.S b/xen/arch/arm/arm64/mmu/head.S
> index 634156f83d..033b3a018a 100644
> --- a/xen/arch/arm/arm64/mmu/head.S
> +++ b/xen/arch/arm/arm64/mmu/head.S
> @@ -313,6 +313,7 @@ END(enable_mmu)
> *
> * Inputs:
> * lr : Virtual address to return to.
> + * x20: phys offset (used by load_paddr)
> *
> * Clobbers x0 - x6
> */
> @@ -337,6 +338,8 @@ END(enable_secondary_cpu_mm)
> *
> * Inputs:
> * lr : Virtual address to return to.
> + * x19: paddr(start) (used by remove_identity_mapping)
AFAICT it's also used by create_page_tables. I don't see it beneficial to
mention the places the register is used. It can easily go stale.
With the remark addressed:
Reviewed-by: Michal Orzel <michal.or...@amd.com>
~Michal
