Introduce a new pci_preserve_config field in virt machine state which
allows the generation of DSM #5. This field is only set if accel SMMU
is instantiated.
In a subsequent patch, SMMUv3 accel mode will make use of IORT RMR nodes
to enable nested translation of MSI doorbell addresses. IORT RMR requires
_DSM #5 to be set for the PCI host bridge so that the Guest kernel
preserves the PCI boot configuration.
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Tested-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Shameer Kolothum <skolothumtho@nvidia.com>
---
hw/arm/virt-acpi-build.c | 8 ++++++++
hw/arm/virt.c | 1 +
include/hw/arm/virt.h | 1 +
3 files changed, 10 insertions(+)
diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
index 03b4342574..9032a5df1c 100644
--- a/hw/arm/virt-acpi-build.c
+++ b/hw/arm/virt-acpi-build.c
@@ -164,6 +164,14 @@ static void acpi_dsdt_add_pci(Aml *scope, const MemMapEntry *memmap,
.pci_native_hotplug = !acpi_pcihp,
};
+ /*
+ * Accel SMMU requires RMRs for MSI 1-1 mapping, which require _DSM
+ * function 5 (_DSM for Preserving PCI Boot Configurations).
+ */
+ if (vms->pci_preserve_config) {
+ cfg.preserve_config = true;
+ }
+
if (vms->highmem_mmio) {
cfg.mmio64 = memmap[VIRT_HIGH_PCIE_MMIO];
}
diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 08feadf0a8..d0321cea2d 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -3071,6 +3071,7 @@ static void virt_machine_device_pre_plug_cb(HotplugHandler *hotplug_dev,
}
object_property_set_uint(OBJECT(dev), "msi-gpa", db_start,
&error_abort);
+ vms->pci_preserve_config = true;
}
}
}
diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
index 8694aaa4e2..2147c6beb4 100644
--- a/include/hw/arm/virt.h
+++ b/include/hw/arm/virt.h
@@ -180,6 +180,7 @@ struct VirtMachineState {
bool ns_el2_virt_timer_irq;
CXLState cxl_devices_state;
bool legacy_smmuv3_present;
+ bool pci_preserve_config;
};
#define VIRT_ECAM_ID(high) (high ? VIRT_HIGH_PCIE_ECAM : VIRT_PCIE_ECAM)
--
2.43.0