hw: acpi: Export and share the ARM RSDP build

Now that build_rsdp() supports building both legacy and current RSDP
tables, we can move it to a generic folder (hw/acpi) and have the i386
ACPI code reuse it in order to reduce code duplication.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>

1 files changed, 19 insertions, 30 deletions

diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index fb87764..9891b69 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -2547,35 +2547,6 @@ build_amd_iommu(GArray *table_data, BIOSLinker *linker)
                  "IVRS", table_data->len - iommu_start, 1, NULL, NULL);
 }
 
-static void
-build_rsdp(GArray *rsdp_table, BIOSLinker *linker, unsigned rsdt_tbl_offset)
-{
-    /* AcpiRsdpDescriptor describes revision 2 RSDP table and as result we
-     * allocate extra 16 bytes for pc/q35 RSDP rev1 as well. Keep extra 16 bytes
-     * wasted to make sure we won't breake migration for machine types older
-     * than 2.3 due to size mismatch.
-     */
-    AcpiRsdpDescriptor *rsdp = acpi_data_push(rsdp_table, sizeof *rsdp);
-    unsigned rsdt_pa_size = sizeof(rsdp->rsdt_physical_address);
-    unsigned rsdt_pa_offset =
-        (char *)&rsdp->rsdt_physical_address - rsdp_table->data;
-
-    bios_linker_loader_alloc(linker, ACPI_BUILD_RSDP_FILE, rsdp_table, 16,
-                             true /* fseg memory */);
-
-    memcpy(&rsdp->signature, "RSD PTR ", 8);
-    memcpy(rsdp->oem_id, ACPI_BUILD_APPNAME6, 6);
-    /* Address to be filled by Guest linker */
-    bios_linker_loader_add_pointer(linker,
-        ACPI_BUILD_RSDP_FILE, rsdt_pa_offset, rsdt_pa_size,
-        ACPI_BUILD_TABLE_FILE, rsdt_tbl_offset);
-
-    /* Checksum to be filled by Guest linker */
-    bios_linker_loader_add_checksum(linker, ACPI_BUILD_RSDP_FILE,
-        (char *)rsdp - rsdp_table->data, 20 /* ACPI rev 1.0 RSDP size */,
-        (char *)&rsdp->checksum - rsdp_table->data);
-}
-
 typedef
 struct AcpiBuildState {
     /* Copy of table in RAM (for patching). */
@@ -2732,7 +2703,25 @@ void acpi_build(AcpiBuildTables *tables, MachineState *machine)
                slic_oem.id, slic_oem.table_id);
 
     /* RSDP is in FSEG memory, so allocate it separately */
-    build_rsdp(tables->rsdp, tables->linker, rsdt);
+    {
+        AcpiRsdpData rsdp_data = {
+            .revision = 0,
+            .oem_id = ACPI_BUILD_APPNAME6,
+            .xsdt_tbl_offset = NULL,
+            .rsdt_tbl_offset = &rsdt,
+        };
+        build_rsdp(tables->rsdp, tables->linker, &rsdp_data);
+        if (!pcmc->rsdp_in_ram) {
+            /* We used to allocate some extra space for RSDP revision 2 but
+             * only used the RSDP revision 0 space. The extra bytes were
+             * zeroed out and not used.
+             * Here we continue wasting those extra 16 bytes to make sure we
+             * don't break migration for machine types 2.2 and older due to
+             * RSDP blob size mismatch.
+             */
+            build_append_int_noprefix(tables->rsdp, 0, 16);
+        }
+    }
 
     /* We'll expose it all to Guest so we want to reduce
      * chance of size changes.