[PATCH v2 3/8] ACPICA: IORT: Update for revision E.f

Rafael J. Wysocki rafael at kernel.org
Thu Aug 29 03:14:54 PDT 2024


On Tue, Aug 27, 2024 at 5:51 PM Jason Gunthorpe <jgg at nvidia.com> wrote:
>
> From: Nicolin Chen <nicolinc at nvidia.com>
>
> ACPICA commit c4f5c083d24df9ddd71d5782c0988408cf0fc1ab
>
> The IORT spec, Issue E.f (April 2024), adds a new CANWBS bit to the Memory
> Access Flag field in the Memory Access Properties table, mainly for a PCI
> Root Complex.
>
> This CANWBS defines the coherency of memory accesses to be not marked IOWB
> cacheable/shareable. Its value further implies the coherency impact from a
> pair of mismatched memory attributes (e.g. in a nested translation case):
>   0x0: Use of mismatched memory attributes for accesses made by this
>        device may lead to a loss of coherency.
>   0x1: Coherency of accesses made by this device to locations in
>        Conventional memory are ensured as follows, even if the memory
>        attributes for the accesses presented by the device or provided by
>        the SMMU are different from Inner and Outer Write-back cacheable,
>        Shareable.
>
> Link: https://github.com/acpica/acpica/commit/c4f5c083
> Signed-off-by: Nicolin Chen <nicolinc at nvidia.com>
> Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>

Acked-by: Rafael J. Wysocki <rafael.j.wysocki at intel.com>

> ---
>  include/acpi/actbl2.h | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/include/acpi/actbl2.h b/include/acpi/actbl2.h
> index e27958ef82642f..9a7acf403ed3c8 100644
> --- a/include/acpi/actbl2.h
> +++ b/include/acpi/actbl2.h
> @@ -453,7 +453,7 @@ struct acpi_table_ccel {
>   * IORT - IO Remapping Table
>   *
>   * Conforms to "IO Remapping Table System Software on ARM Platforms",
> - * Document number: ARM DEN 0049E.e, Sep 2022
> + * Document number: ARM DEN 0049E.f, Apr 2024
>   *
>   ******************************************************************************/
>
> @@ -524,6 +524,7 @@ struct acpi_iort_memory_access {
>
>  #define ACPI_IORT_MF_COHERENCY          (1)
>  #define ACPI_IORT_MF_ATTRIBUTES         (1<<1)
> +#define ACPI_IORT_MF_CANWBS             (1<<2)
>
>  /*
>   * IORT node specific subtables
> --
> 2.46.0
>
>



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