Re: [RFC PATCH v2 1/8] ACPICA: IORT: Update for revision E

[Jon Nettleton <jon@solid-run.com>]

On Mon, Mar 22, 2021 at 11:37 AM Shameerali Kolothum Thodi
<shameerali.kolothum.thodi@huawei.com> wrote:
>
> [+]
>
> Hi Erik,
>
> As this is now just merged ino acpica-master and based on the discussion we had here,
>
> https://github.com/acpica/acpica/pull/638
>
> I had a discussion with ARM folks(Lorenzo) in the linaro-open-discussions call and
> can confirm that the IORT Revision E is not the final specification and has some issues
> which is now corrected in the latest E.b revision[1]. Also there are no current users
> for the Rev E and it may not be a good idea to push this version into the Linux kernel
> or elsewhere.

Well it was a released revision, although it was found to have issues.
Currently
HoneyComb Systems Ready certified firmware does include support for this table,
although incomplete.  Without agreement on mainline support I am fine to update
to the latest spec bump.

>
> So could you please revert the merge and I am planning to work on the E.b soon.
> Please let me know if I need to explicitly send a revert pull request or not.

Can you please CC. me on your next release.  I was planning on spending time
on this regardless.  I already have a patchset for the fsl-mc-bus driver that
needs to change in order to function properly with RMR support.

Thanks.

>
> Thanks,
> Shameer
>
> 1. https://developer.arm.com/documentation/den0049/latest/
>
> > -----Original Message-----
> > From: iommu [mailto:iommu-bounces@lists.linux-foundation.org] On Behalf Of
> > Shameer Kolothum
> > Sent: 19 November 2020 12:12
> > To: linux-arm-kernel@lists.infradead.org; linux-acpi@vger.kernel.org;
> > iommu@lists.linux-foundation.org; devel@acpica.org
> > Cc: Linuxarm <linuxarm@huawei.com>; steven.price@arm.com; Guohanjun
> > (Hanjun Guo) <guohanjun@huawei.com>; Sami.Mujawar@arm.com;
> > robin.murphy@arm.com; wanghuiqiang <wanghuiqiang@huawei.com>
> > Subject: [RFC PATCH v2 1/8] ACPICA: IORT: Update for revision E
> >
> > IORT revision E contains a few additions like,
> >     -Added an identifier field in the node descriptors to aid table
> >      cross-referencing.
> >     -Introduced the Reserved Memory Range(RMR) node. This is used
> >      to describe memory ranges that are used by endpoints and requires
> >      a unity mapping in SMMU.
> >     -Introduced a flag in the RC node to express support for PRI.
> >
> > Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
> > ---
> >  include/acpi/actbl2.h | 25 +++++++++++++++++++------
> >  1 file changed, 19 insertions(+), 6 deletions(-)
> >
> > diff --git a/include/acpi/actbl2.h b/include/acpi/actbl2.h index
> > ec66779cb193..274fce7b5c01 100644
> > --- a/include/acpi/actbl2.h
> > +++ b/include/acpi/actbl2.h
> > @@ -68,7 +68,7 @@
> >   * IORT - IO Remapping Table
> >   *
> >   * Conforms to "IO Remapping Table System Software on ARM Platforms",
> > - * Document number: ARM DEN 0049D, March 2018
> > + * Document number: ARM DEN 0049E, June 2020
> >   *
> >
> > ****************************************************************
> > **************/
> >
> > @@ -86,7 +86,8 @@ struct acpi_iort_node {
> >       u8 type;
> >       u16 length;
> >       u8 revision;
> > -     u32 reserved;
> > +     u16 reserved;
> > +     u16 identifier;
> >       u32 mapping_count;
> >       u32 mapping_offset;
> >       char node_data[1];
> > @@ -100,7 +101,8 @@ enum acpi_iort_node_type {
> >       ACPI_IORT_NODE_PCI_ROOT_COMPLEX = 0x02,
> >       ACPI_IORT_NODE_SMMU = 0x03,
> >       ACPI_IORT_NODE_SMMU_V3 = 0x04,
> > -     ACPI_IORT_NODE_PMCG = 0x05
> > +     ACPI_IORT_NODE_PMCG = 0x05,
> > +     ACPI_IORT_NODE_RMR = 0x06,
> >  };
> >
> >  struct acpi_iort_id_mapping {
> > @@ -167,10 +169,10 @@ struct acpi_iort_root_complex {
> >       u8 reserved[3];         /* Reserved, must be zero */
> >  };
> >
> > -/* Values for ats_attribute field above */
> > +/* Masks for ats_attribute field above */
> >
> > -#define ACPI_IORT_ATS_SUPPORTED         0x00000001   /* The root
> > complex supports ATS */
> > -#define ACPI_IORT_ATS_UNSUPPORTED       0x00000000   /* The root
> > complex doesn't support ATS */
> > +#define ACPI_IORT_ATS_SUPPORTED         (1)  /* The root complex
> > supports ATS */
> > +#define ACPI_IORT_PRI_SUPPORTED         (1<<1)       /* The root complex
> > supports PRI */
> >
> >  struct acpi_iort_smmu {
> >       u64 base_address;       /* SMMU base address */
> > @@ -241,6 +243,17 @@ struct acpi_iort_pmcg {
> >       u64 page1_base_address;
> >  };
> >
> > +struct acpi_iort_rmr {
> > +     u32 rmr_count;
> > +     u32 rmr_offset;
> > +};
> > +
> > +struct acpi_iort_rmr_desc {
> > +     u64 base_address;
> > +     u64 length;
> > +     u32 reserved;
> > +};
> > +
> >
> > /***************************************************************
> > ****************
> >   *
> >   * IVRS - I/O Virtualization Reporting Structure
> > --
> > 2.17.1
> >
> > _______________________________________________
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> > iommu@lists.linux-foundation.org
> > https://lists.linuxfoundation.org/mailman/listinfo/iommu
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