Hi Palmer,.
On Fri, Apr 22, 2022 at 11:42 PM Palmer Dabbelt <palmer@xxxxxxxxxxxx> wrote:
> Similar to the previous patch, this allows a dt-selected downgrade to
> sv48 on systems that support sv57 in case users don't need the extra VA
> bits and want to save memory or improve performance.
>
> Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
> ---
> This is on top of the patches from Alex's set that I dropped.
You mean "[PATCH v3 13/13] riscv: Allow user to downgrade to sv39
when hw supports sv48 if !KASAN"?
20211206104657.433304-14-alexandre.ghiti@xxxxxxxxxxxxx
For both: "DT describes hardware, not software policy"?
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -740,6 +740,11 @@ static __init void set_satp_mode(uintptr_t dtb_pa)
> if (!mmu_type)
> continue;
>
> + if (!strcmp(mmu_type, "riscv,sv48")) {
> + disable_pgtable_l5();
> + return;
> + }
> +
> if (!strcmp(mmu_type, "riscv,sv39")) {
> disable_pgtable_l5();
> disable_pgtable_l4();
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
