From e9b0d476172e872bf695780a9ffa8072faeb3cd0 Mon Sep 17 00:00:00 2001
From: Jean-Philippe Brucker <jean-philippe@linaro.org>
Date: Mon, 25 Apr 2022 17:40:57 +0100
Subject: [PATCH] hw/acpi: Make _MAT method optional

The GICC interface on arm64 vCPUs is statically defined in the MADT, and
doesn't require a _MAT entry. Although the GICC is indicated as present
by the MADT entry, it can only be used from vCPU sysregs, which aren't
accessible until hot-add.

Co-developed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Co-developed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
---
 hw/acpi/cpu.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/hw/acpi/cpu.c b/hw/acpi/cpu.c
index 991f1d4181..c922c380aa 100644
--- a/hw/acpi/cpu.c
+++ b/hw/acpi/cpu.c
@@ -720,9 +720,11 @@ void build_cpus_aml(Aml *table, MachineState *machine, CPUHotplugFeatures opts,
             aml_append(dev, method);
 
             /* build _MAT object */
-            build_madt_cpu(i, arch_ids, madt_buf, true); /* set enabled flag */
-            aml_append(dev, aml_name_decl("_MAT",
-                aml_buffer(madt_buf->len, (uint8_t *)madt_buf->data)));
+            if (build_madt_cpu) {
+                build_madt_cpu(i, arch_ids, madt_buf, true); /* set enabled flag */
+                aml_append(dev, aml_name_decl("_MAT",
+                    aml_buffer(madt_buf->len, (uint8_t *)madt_buf->data)));
+            }
             g_array_free(madt_buf, true);
 
             if (CPU(arch_ids->cpus[i].cpu) != first_cpu) {
-- 
2.27.0