Re: [PATCH V4 05/23] ACPI: OSL: Make should_use_kmap() 0 for RISC-V

[Björn Töpel]

Sunil V L <sunilvl@xxxxxxxxxxxxxxxx> writes:

> Without this, if the tables are larger than 4K,
> acpi_map() will fail.
>
> Signed-off-by: Sunil V L <sunilvl@xxxxxxxxxxxxxxxx>
> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> ---
>  drivers/acpi/osl.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
> index 3269a888fb7a..f725813d0cce 100644
> --- a/drivers/acpi/osl.c
> +++ b/drivers/acpi/osl.c
> @@ -276,7 +276,7 @@ acpi_map_lookup_virt(void __iomem *virt, acpi_size size)
>  	return NULL;
>  }
>  
> -#if defined(CONFIG_IA64) || defined(CONFIG_ARM64)
> +#if defined(CONFIG_IA64) || defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
>  /* ioremap will take care of cache attributes */
>  #define should_use_kmap(pfn)   0

An observation, which can be addressed later; The acpi_os_ioremap()
(called when the config above is enabled for RV), does not have an arch
specific implementation for RISC-V. The generic one calls
ioremap_cached(), which on RISC-V defaults to ioremap() -- caching
disabled/_PAGE_IO.

That is probably not what we want, but rather something similar that
arm64 does.


Björn