On Thu, Nov 29, 2018 at 02:24:26PM +0100, Samuel Ortiz 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 <sa...@linux.intel.com>
> ---
> hw/arm/virt-acpi-build.c | 37 ++++++++++++++++++++++++++-----------
> 1 file changed, 26 insertions(+), 11 deletions(-)
>
> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> index 4782aea4fe..e1338b6f5a 100644
> --- a/hw/arm/virt-acpi-build.c
> +++ b/hw/arm/virt-acpi-build.c
> @@ -378,23 +378,38 @@ 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 */
> - build_append_int_noprefix(tbl, 36, 4); /* Length */
> -
> - /* XSDT address to be filled by guest linker */
> - build_append_int_noprefix(tbl, 0, 8); /* XsdtAddress */
> - bios_linker_loader_add_pointer(linker, ACPI_BUILD_RSDP_FILE,
> - 24, 8,
> - ACPI_BUILD_TABLE_FILE,
> - *rsdp_data->xsdt_tbl_offset);
> -
> - build_append_int_noprefix(tbl, 0, 1); /* Extended Checksum */
> - build_append_int_noprefix(tbl, 0, 3); /* Reserved */
> + if (rsdp_data->rsdt_tbl_offset) {
I see why a pointer was used now. Using a pointer ensures a zero
offset won't fail this test. However the test could be replaced with
rsdp_data->revision == 0.
> + /* RSDT address to be filled by guest linker */
> + bios_linker_loader_add_pointer(linker,
> + ACPI_BUILD_RSDP_FILE, 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,
> 0, 20, /* ACPI rev 1.0 RSDP size */
> 8);
>
> + if (rsdp_data->revision == 0) {
> + /* ACPI 1.0 RSDP, we're done */
> + return;
> + }
> +
> + /* The RSDP revision is 2 and later, we must have an XSDT pointer */
> + g_assert(rsdp_data->xsdt_tbl_offset != NULL);
So here's the justification for the pointers. We sanity check the callers.
We're missing the (rsdp_data->revision == 0 && rsdp_data->rsdt_tbl_offset)
sanity check though.
> +
> + build_append_int_noprefix(tbl, 36, 4); /* Length */
> +
> + /* XSDT address to be filled by guest linker */
> + build_append_int_noprefix(tbl, 0, 8); /* XsdtAddress */
> + bios_linker_loader_add_pointer(linker, ACPI_BUILD_RSDP_FILE, 24, 8,
> + ACPI_BUILD_TABLE_FILE,
> + *rsdp_data->xsdt_tbl_offset);
> +
> + build_append_int_noprefix(tbl, 0, 1); /* Extended Checksum */
> + build_append_int_noprefix(tbl, 0, 3); /* Reserved */
> +
> /* Extended checksum to be filled by Guest linker */
> bios_linker_loader_add_checksum(linker, ACPI_BUILD_RSDP_FILE,
> 0, 36, /* ACPI rev 2.0 RSDP size */
> --
> 2.19.2
>
>
Thanks,
drew
