Re: [Qemu-devel] [PATCH v3 6/8] hw: arm: Support both legacy and current RSDP build

[Igor Mammedov <imammedo@redhat.com>]

On Fri, 30 Nov 2018 14:00:30 +0100
Samuel Ortiz <sameo@linux.intel.com> wrote:

> We add the ability to build legacy or current RSDP tables, based on the
> AcpiRsdpData revision field passed to build_rsdp().
> Although arm/virt only uses RSDP v2, adding that capability to
> build_rsdp will allow us to share the RSDP build code between ARM and x86.
> 
> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
> Reviewed-by: Igor Mammedov <imammedo@redhat.com>
> ---
>  hw/arm/virt-acpi-build.c | 39 ++++++++++++++++++++++++++++++++++-----
>  1 file changed, 34 insertions(+), 5 deletions(-)
> 
> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> index 4a6b53fbfc..4b212fa44c 100644
> --- a/hw/arm/virt-acpi-build.c
> +++ b/hw/arm/virt-acpi-build.c
> @@ -370,8 +370,23 @@ static void acpi_dsdt_add_power_button(Aml *scope)
>  static void
>  build_rsdp(GArray *tbl, BIOSLinker *linker, AcpiRsdpData *rsdp_data)
>  {
> +
unrelated white space change
 (you can do v4 of this patch as reply to this patch and add changelog below ---
  so it would be clear what's changed)

>      int tbl_off = tbl->len; /* Table offset in the RSDP file */
>  
> +    switch (rsdp_data->revision) {
> +    case 0:
> +        /* With ACPI 1.0, we must have an RSDT pointer */
> +        g_assert(rsdp_data->rsdt_tbl_offset);
> +        break;
> +    case 2:
> +        /* With ACPI 2.0+, we must have an XSDT pointer */
> +        g_assert(rsdp_data->xsdt_tbl_offset);
> +        break;
> +    default:
> +        /* Only revisions 0 (ACPI 1.0) and 2 (ACPI 2.0+) are valid for RSDP */
> +        g_assert_not_reached();
> +    }
> +
>      bios_linker_loader_alloc(linker, ACPI_BUILD_RSDP_FILE, tbl, 16,
>                               true /* fseg memory */);
>  
> @@ -380,10 +395,29 @@ build_rsdp(GArray *tbl, BIOSLinker *linker, AcpiRsdpData *rsdp_data)
>      g_array_append_vals(tbl, rsdp_data->oem_id, 6); /* OEMID */
>      build_append_int_noprefix(tbl, rsdp_data->revision, 1); /* Revision */
>      build_append_int_noprefix(tbl, 0, 4); /* RsdtAddress */
> +    if (rsdp_data->rsdt_tbl_offset) {
> +        /* RSDT address to be filled by guest linker */
> +        bios_linker_loader_add_pointer(linker, ACPI_BUILD_RSDP_FILE,
> +                                       tbl_off + 16, 4,
> +                                       ACPI_BUILD_TABLE_FILE,
> +                                       *rsdp_data->rsdt_tbl_offset);
> +    }
> +
> +    /* Checksum to be filled by guest linker */
> +    bios_linker_loader_add_checksum(linker, ACPI_BUILD_RSDP_FILE,
> +                                    tbl_off, 20, /* ACPI rev 1.0 RSDP size */
> +                                    8);
> +
> +    if (rsdp_data->revision == 0) {
> +        /* ACPI 1.0 RSDP, we're done */
> +        return;
> +    }
> +
>      build_append_int_noprefix(tbl, 36, 4); /* Length */
>  
>      /* XSDT address to be filled by guest linker */
>      build_append_int_noprefix(tbl, 0, 8); /* XsdtAddress */
> +    /* We already validated our xsdt pointer */
>      bios_linker_loader_add_pointer(linker, ACPI_BUILD_RSDP_FILE,
>                                     tbl_off + 24, 8,
>                                     ACPI_BUILD_TABLE_FILE,
> @@ -392,11 +426,6 @@ build_rsdp(GArray *tbl, BIOSLinker *linker, AcpiRsdpData *rsdp_data)
>      build_append_int_noprefix(tbl, 0, 1); /* Extended Checksum */
>      build_append_int_noprefix(tbl, 0, 3); /* Reserved */
>  
> -    /* Checksum to be filled by guest linker */
> -    bios_linker_loader_add_checksum(linker, ACPI_BUILD_RSDP_FILE,
> -                                    tbl_off, 20, /* ACPI rev 1.0 RSDP size */
> -                                    8);
> -
>      /* Extended checksum to be filled by Guest linker */
>      bios_linker_loader_add_checksum(linker, ACPI_BUILD_RSDP_FILE,
>                                      tbl_off, 36, /* ACPI rev 2.0 RSDP size */