Re: [RFC V2 10/10] arm64/mm: Enable CONFIG_ARM64_PA_BITS_52 on CONFIG_ARM64_[4K|16K]_PAGES

From: Catalin Marinas
Date: Thu Aug 05 2021 - 13:23:30 EST


On Mon, Jul 26, 2021 at 12:07:25PM +0530, Anshuman Khandual wrote:
> All required FEAT_LPA2 components for 52 bit PA range are already in place.
> Just enable CONFIG_ARM64_PA_BITS_52 on 4K and 16K pages which would select
> CONFIG_ARM64_PA_BITS_52_LPA2 activating 52 bit PA range via FEAT_LPA2.
>
> Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
> ---
> arch/arm64/Kconfig | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 1999ac6..ce139415 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -952,9 +952,9 @@ config ARM64_PA_BITS_48
>
> config ARM64_PA_BITS_52
> bool "52-bit (ARMv8.2)"
> - depends on ARM64_64K_PAGES
> depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
> select ARM64_PA_BITS_52_LPA if ARM64_64K_PAGES
> + select ARM64_PA_BITS_52_LPA2 if (ARM64_4K_PAGES || ARM64_16K_PAGES)
> help
> Enable support for a 52-bit physical address space, introduced as
> part of the ARMv8.2-LPA extension.

If you do it this way, the text here needs updating and the 8.2
architecture version removed.

--
Catalin