libacpi: set FADT boot flag to notify lack of VGA for PVHv2 guests

PVHv2 guests don't have any VGA card, and as so it must be notified in the FADT.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

tools/firmware/hvmloader/util.c

@@ -950,7 +950,7 @@ void hvmloader_acpi_build_tables(struct acpi_config *config,
 
     config->table_flags |= (ACPI_HAS_TCPA | ACPI_HAS_IOAPIC |
                             ACPI_HAS_WAET | ACPI_HAS_PMTIMER |
-                            ACPI_HAS_BUTTONS);
+                            ACPI_HAS_BUTTONS | ACPI_HAS_VGA);
 
     config->tis_hdr = (uint16_t *)ACPI_TIS_HDR_ADDRESS;
 

tools/libacpi/acpi2_0.h

@@ -229,6 +229,7 @@ struct acpi_20_fadt {
  */
 #define ACPI_FADT_LEGACY_DEVICES    (1 << 0)
 #define ACPI_FADT_8042              (1 << 1)
+#define ACPI_FADT_NO_VGA            (1 << 2)
 
 /*
  * FADT Fixed Feature Flags.

tools/libacpi/build.c

@@ -586,6 +586,8 @@ int acpi_build_tables(struct acpi_ctxt *ctxt, struct acpi_config *config)
     fadt->x_dsdt = ctxt->mem_ops.v2p(ctxt, dsdt);
     fadt->firmware_ctrl   = ctxt->mem_ops.v2p(ctxt, facs);
     fadt->x_firmware_ctrl = ctxt->mem_ops.v2p(ctxt, facs);
+    if ( !(config->table_flags & ACPI_HAS_VGA) )
+        fadt->iapc_boot_arch |= ACPI_FADT_NO_VGA;
     set_checksum(fadt,
                  offsetof(struct acpi_header, checksum),
                  sizeof(struct acpi_20_fadt));

tools/libacpi/libacpi.h

@@ -32,6 +32,7 @@
 #define ACPI_HAS_WAET        (1<<9)
 #define ACPI_HAS_PMTIMER     (1<<10)
 #define ACPI_HAS_BUTTONS     (1<<11)
+#define ACPI_HAS_VGA         (1<<12)
 
 struct xen_vmemrange;
 struct acpi_numa {