Re: [Qemu-devel] [V11 2/4] hw/i386: ACPI IVRS table

[Valentine Sinitsyn]

Hi all,

On 24.05.2016 11:54, Peter Xu wrote:
> On Sun, May 22, 2016 at 01:21:52PM +0300, David Kiarie wrote:
> [...]
> > +static void
> > +build_amd_iommu(GArray *table_data, GArray *linker)
> > +{
> > +    int iommu_start = table_data->len;
> > +    bool iommu_ambig;
> > +
> > +    /* IVRS definition  - table header has an extra 2-byte field */
> > +    acpi_data_push(table_data, (sizeof(AcpiTableHeader)));
> > +    /* common virtualization information */
> > +    build_append_int_noprefix(table_data, AMD_IOMMU_HOST_ADDRESS_WIDTH << 8, 
> > 4);
> > +    /* reserved */
> > +    build_append_int_noprefix(table_data, 0, 8);
> > +
> > +    AMDVIState *s = (AMDVIState *)object_resolve_path_type("",
> > +                        TYPE_AMD_IOMMU_DEVICE, &iommu_ambig);
> > +
> > +    /* IVDB definition - type 10h */
> > +    if (!iommu_ambig) {
> > +        /* IVHD definition - type 10h */
> > +        build_append_int_noprefix(table_data, 0x10, 1);
> > +        /* virtualization flags */
> > +        build_append_int_noprefix(table_data, (IVHD_HT_TUNEN |
> > +                     IVHD_PPRSUP | IVHD_IOTLBSUP | IVHD_PREFSUP), 1);
> > +        /* ivhd length */
> > +        build_append_int_noprefix(table_data, 0x20, 2);
> > +        /* iommu device id */
> > +        build_append_int_noprefix(table_data, PCI_DEVICE_ID_RD890_IOMMU, 2);
> > +        /* offset of capability registers */
> > +        build_append_int_noprefix(table_data, s->capab_offset, 2);
> > +        /* mmio base register */
> > +        build_append_int_noprefix(table_data, s->mmio.addr, 8);
> > +        /* pci segment */
> > +        build_append_int_noprefix(table_data, 0, 2);
> > +        /* interrupt numbers */
> > +        build_append_int_noprefix(table_data, 0, 2);
> > +        /* feature reporting */
> > +        build_append_int_noprefix(table_data, (IVHD_EFR_GTSUP |
> > +                    IVHD_EFR_HATS | IVHD_EFR_GATS), 4);
> > +        /* Add device flags here
> > +         *   These are 4-byte device entries currently reporting the range of
> > +         *   devices 00h - ffffh; all devices
> > +         *   Device setting affecting all devices should be made here
> > +         *
> > +         *   Refer to
> > +         *   (http://developer.amd.com/wordpress/media/2012/10/488821.pdf)
> > +         *   Table 95
>
> I failed to find Table 95 in the document. Is that typo?
I guess it should be "Table 75". David, am I right?
On a side note, 2.0 specification you mention is rather outdated.
Please consider referencing something newer, like 2.6.

> [...]
>
> >   static
> >   void acpi_build(AcpiBuildTables *tables, MachineState *machine)
> >   {
> > @@ -2657,6 +2721,7 @@ void acpi_build(AcpiBuildTables *tables, MachineState 
> > *machine)
> >       AcpiMcfgInfo mcfg;
> >       PcPciInfo pci;
> >       uint8_t *u;
> > +    IommuType IOMMUType = has_iommu();
> >       size_t aml_len = 0;
> >       GArray *tables_blob = tables->table_data;
> >       AcpiSlicOem slic_oem = { .id = NULL, .table_id = NULL };
> > @@ -2722,7 +2787,13 @@ void acpi_build(AcpiBuildTables *tables, MachineState 
> > *machine)
> >           acpi_add_table(table_offsets, tables_blob);
> >           build_mcfg_q35(tables_blob, tables->linker, &mcfg);
> >       }
> > -    if (acpi_has_iommu()) {
> > +
> > +    if (IOMMUType == TYPE_AMD) {
> > +        acpi_add_table(table_offsets, tables_blob);
> > +        build_amd_iommu(tables_blob, tables->linker);
> > +    }
> > +
> > +    if (IOMMUType == TYPE_INTEL) {
> >           acpi_add_table(table_offsets, tables_blob);
> >           build_dmar_q35(tables_blob, tables->linker);
> >       }
>
> Nit: I'd prefer:
>
>      if (type == Intel) {
>      ...
>      } else if (type == AMD) {
>      ...
>      }
>
> for better readability.
>
> Thanks,
>
> -- peterx

Best,
Valentine