hw/arm/virt: Declare virtio-mmio as dma cache coherent in ACPI

Virtio-mmio devices can directly access guest memory and do so in cache
coherent fashion. Tell the guest about that fact when it's using ACPI.

Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Shannon Zhao <shannon.zhao@linaro.org>
Message-id: 1486644810-33181-3-git-send-email-agraf@suse.de
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
index 07a10aca40418867a4cb5881b61c7440df28eba2..8955a9d3840d44e9dfc96390ed01255048d47a93 100644 (file)
--- a/hw/arm/virt-acpi-build.c
+++ b/hw/arm/virt-acpi-build.c
@@ -135,6 +135,7 @@ static void acpi_dsdt_add_virtio(Aml *scope,
         Aml *dev = aml_device("VR%02u", i);
         aml_append(dev, aml_name_decl("_HID", aml_string("LNRO0005")));
         aml_append(dev, aml_name_decl("_UID", aml_int(i)));
+        aml_append(dev, aml_name_decl("_CCA", aml_int(1)));
 
         Aml *crs = aml_resource_template();
         aml_append(crs, aml_memory32_fixed(base, size, AML_READ_WRITE));