[PATCH v3 2/9] ACPICA: IORT: Update for revision E.f

Hanjun Guo guohanjun at huawei.com
Wed Oct 9 18:48:55 PDT 2024


On 2024/10/10 0:23, Jason Gunthorpe 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.
> 

Acked-by: Hanjun Guo <guohanjun at huawei.com>

Thanks
Hanjun



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