Re: [PATCH 1/3] iommu/vt-d: Add new enum value and structure for SATC

[Lu Baolu]

Hi Ashok,

On 2/3/21 12:02 AM, Raj, Ashok wrote:
> On Tue, Feb 02, 2021 at 12:40:55PM +0800, Lu Baolu wrote:
> > From: Yian Chen <yian.chen@xxxxxxxxx>
> >
> > Starting from Intel Platform VT-d v3.2, BIOS may provide new remapping
> > structure SATC for SOC integrated devices, according to section 8.8 of
> > Intel VT-d architecture specification v3.2. The SATC structure reports
> > a list of the devices that require SATC enabling via ATS capacity.
>
> nit: s/require SATC/require ATS for normal device operation. This is a
> functional requirement that these devices will not work without OS enabling
> ATS capability.

Yes. This looks clearer.

Best regards,
baolu

> > This patch introduces the new enum value and structure to represent the
> > remapping information. Kernel should parse the information from the
> > reporting structure and enable ATC for the devices as needed.
> >
> > Signed-off-by: Yian Chen <yian.chen@xxxxxxxxx>
> > ---
> >   include/acpi/actbl1.h | 11 ++++++++++-
> >   1 file changed, 10 insertions(+), 1 deletion(-)
> >
> > diff --git a/include/acpi/actbl1.h b/include/acpi/actbl1.h
> > index 43549547ed3e..b7ca802b66d2 100644
> > --- a/include/acpi/actbl1.h
> > +++ b/include/acpi/actbl1.h
> > @@ -514,7 +514,8 @@ enum acpi_dmar_type {
> >   	ACPI_DMAR_TYPE_ROOT_ATS = 2,
> >   	ACPI_DMAR_TYPE_HARDWARE_AFFINITY = 3,
> >   	ACPI_DMAR_TYPE_NAMESPACE = 4,
> > -	ACPI_DMAR_TYPE_RESERVED = 5	/* 5 and greater are reserved */
> > +	ACPI_DMAR_TYPE_SATC = 5,
> > +	ACPI_DMAR_TYPE_RESERVED = 6	/* 5 and greater are reserved */
> >   };
> >   
>
> Think Joerg spotted the comment update.