Accelerated SMMUv3 instances rely on the physical SMMUv3 for nested
translation (guest Stage-1, host Stage-2). In this mode, the guest Stage-1
tables are programmed directly into hardware, and QEMU must not attempt to
walk them for translation, as doing so is not reliably safe. For vfio-pci
endpoints behind such a vSMMU, the only translation QEMU needs to perform
is for the MSI doorbell used during KVM MSI setup.
Implement the callback so that kvm_arch_fixup_msi_route() can retrieve the
MSI doorbell GPA directly, instead of attempting a software walk of the
guest translation tables.
Also introduce an SMMUv3 device property to carry the MSI doorbell GPA.
This property will be set by the virt machine in a subsequent patch.
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Signed-off-by: Shameer Kolothum <skolothumtho@nvidia.com>
---
hw/arm/smmuv3-accel.c | 10 ++++++++++
hw/arm/smmuv3.c | 2 ++
include/hw/arm/smmuv3.h | 1 +
3 files changed, 13 insertions(+)
diff --git a/hw/arm/smmuv3-accel.c b/hw/arm/smmuv3-accel.c
index c125974d12..c6ee123cdf 100644
--- a/hw/arm/smmuv3-accel.c
+++ b/hw/arm/smmuv3-accel.c
@@ -393,6 +393,15 @@ static void smmuv3_accel_unset_iommu_device(PCIBus *bus, void *opaque,
}
}
+static uint64_t smmuv3_accel_get_msi_gpa(PCIBus *bus, void *opaque, int devfn)
+{
+ SMMUState *bs = opaque;
+ SMMUv3State *s = ARM_SMMUV3(bs);
+
+ g_assert(s->msi_gpa);
+ return s->msi_gpa;
+}
+
/*
* Only allow PCIe bridges, pxb-pcie roots, and GPEX roots so vfio-pci
* endpoints can sit downstream. Accelerated SMMUv3 requires a vfio-pci
@@ -497,6 +506,7 @@ static const PCIIOMMUOps smmuv3_accel_ops = {
.get_viommu_flags = smmuv3_accel_get_viommu_flags,
.set_iommu_device = smmuv3_accel_set_iommu_device,
.unset_iommu_device = smmuv3_accel_unset_iommu_device,
+ .get_msi_direct_gpa = smmuv3_accel_get_msi_gpa,
};
/* Based on SMUUv3 GPBA.ABORT configuration, attach a corresponding HWPT */
diff --git a/hw/arm/smmuv3.c b/hw/arm/smmuv3.c
index 7a32afd800..6ed9914b1e 100644
--- a/hw/arm/smmuv3.c
+++ b/hw/arm/smmuv3.c
@@ -1998,6 +1998,8 @@ static const Property smmuv3_properties[] = {
* Defaults to stage 1
*/
DEFINE_PROP_STRING("stage", SMMUv3State, stage),
+ /* GPA of MSI doorbell, for SMMUv3 accel use. */
+ DEFINE_PROP_UINT64("msi-gpa", SMMUv3State, msi_gpa, 0),
};
static void smmuv3_instance_init(Object *obj)
diff --git a/include/hw/arm/smmuv3.h b/include/hw/arm/smmuv3.h
index e54ece2d38..5616a8a2be 100644
--- a/include/hw/arm/smmuv3.h
+++ b/include/hw/arm/smmuv3.h
@@ -67,6 +67,7 @@ struct SMMUv3State {
/* SMMU has HW accelerator support for nested S1 + s2 */
bool accel;
struct SMMUv3AccelState *s_accel;
+ uint64_t msi_gpa;
};
typedef enum {
--
2.43.0