Hi Nathan,
On 3/9/26 8:21 PM, Nathan Chen wrote:
> From: Nathan Chen <[email protected]>
>
> Allow accelerated SMMUv3 Address Translation Services support property
> to be derived from host IOMMU capabilities. Derive host values using
> IOMMU_GET_HW_INFO, retrieving ATS capability from IDR0.
>
> Set the default value of ATS to auto. The default for ATS support used
> to be set to off, but we change it to match what the host IOMMU
> properties report.
>
> Add a "ats-enabled" read-only property for smmuv3 to address an
> expected bool for the "ats" property in iort_smmuv3_devices().
>
> Signed-off-by: Nathan Chen <[email protected]>
> ---
> hw/arm/smmuv3-accel.c | 25 +++++++++++++++++++++++--
> hw/arm/smmuv3.c | 12 ++++++++++--
> hw/arm/virt-acpi-build.c | 2 +-
> include/hw/arm/smmuv3.h | 2 +-
> 4 files changed, 35 insertions(+), 6 deletions(-)
>
> diff --git a/hw/arm/smmuv3-accel.c b/hw/arm/smmuv3-accel.c
> index 617629bacd..8fec335557 100644
> --- a/hw/arm/smmuv3-accel.c
> +++ b/hw/arm/smmuv3-accel.c
> @@ -52,6 +52,12 @@ static void smmuv3_accel_auto_finalise(SMMUv3State *s,
> PCIDevice *pdev,
> return;
> }
>
> + /* Update ATS if auto from info */
> + if (s->ats == ON_OFF_AUTO_AUTO) {
> + s->idr[0] = FIELD_DP32(s->idr[0], IDR0, ATS,
> + FIELD_EX32(info->idr[0], IDR0, ATS));
> + }
> +
> accel->auto_finalised = true;
> }
>
> @@ -124,6 +130,13 @@ smmuv3_accel_check_hw_compatible(SMMUv3State *s,
> smmuv3_oas_bits(FIELD_EX32(s->idr[5], IDR5, OAS)));
> return false;
> }
> + /* Check ATS value opted is compatible with Host SMMUv3 */
> + if (FIELD_EX32(info->idr[0], IDR0, ATS) <
> + FIELD_EX32(s->idr[0], IDR0, ATS)) {
> + error_setg(errp, "Host SMMUv3 doesn't support Address Translation"
> + " Services");
> + return false;
> + }
Shouldn't this chunk be a separate fix for previous accel SMMU series?
>
> /* QEMU SMMUv3 supports GRAN4K/GRAN16K/GRAN64K translation granules */
> if (FIELD_EX32(info->idr[5], IDR5, GRAN4K) !=
> @@ -844,8 +857,12 @@ void smmuv3_accel_idr_override(SMMUv3State *s)
> /* By default QEMU SMMUv3 has RIL. Update IDR3 if user has disabled it */
> s->idr[3] = FIELD_DP32(s->idr[3], IDR3, RIL, s->ril);
>
> - /* QEMU SMMUv3 has no ATS. Advertise ATS if opt-in by property */
> - s->idr[0] = FIELD_DP32(s->idr[0], IDR0, ATS, s->ats);
> + /* Only override ATS if user explicitly set ON or OFF */
> + if (s->ats == ON_OFF_AUTO_ON) {
> + s->idr[0] = FIELD_DP32(s->idr[0], IDR0, ATS, 1);
> + } else if (s->ats == ON_OFF_AUTO_OFF) {
> + s->idr[0] = FIELD_DP32(s->idr[0], IDR0, ATS, 0);
> + }
>
> /* Advertise 48-bit OAS in IDR5 when requested (default is 44 bits). */
> if (s->oas == SMMU_OAS_48BIT) {
> @@ -923,4 +940,8 @@ void smmuv3_accel_init(SMMUv3State *s)
> s->s_accel = g_new0(SMMUv3AccelState, 1);
> bs->iommu_ops = &smmuv3_accel_ops;
> smmuv3_accel_as_init(s);
> +
> + if (s->ats == ON_OFF_AUTO_AUTO) {
> + s->s_accel->auto_mode = true;
> + }
> }
> diff --git a/hw/arm/smmuv3.c b/hw/arm/smmuv3.c
> index 068108e49b..197ba7c77b 100644
> --- a/hw/arm/smmuv3.c
> +++ b/hw/arm/smmuv3.c
> @@ -317,6 +317,12 @@ static void smmuv3_init_id_regs(SMMUv3State *s)
> smmuv3_accel_idr_override(s);
> }
>
> +static bool get_ats_enabled(Object *obj, Error **errp)
> +{
> + SMMUv3State *s = ARM_SMMUV3(obj);
> + return FIELD_EX32(s->idr[0], IDR0, ATS);
> +}
> +
> static void smmuv3_reset(SMMUv3State *s)
> {
> s->cmdq.base = deposit64(s->cmdq.base, 0, 5, SMMU_CMDQS);
> @@ -1971,7 +1977,7 @@ static bool smmu_validate_property(SMMUv3State *s,
> Error **errp)
> error_setg(errp, "ril can only be disabled if accel=on");
> return false;
> }
> - if (s->ats) {
> + if (s->ats == ON_OFF_AUTO_ON) {
> error_setg(errp, "ats can only be enabled if accel=on");
> return false;
> }
> @@ -2128,7 +2134,7 @@ static const Property smmuv3_properties[] = {
> DEFINE_PROP_UINT64("msi-gpa", SMMUv3State, msi_gpa, 0),
> /* RIL can be turned off for accel cases */
> DEFINE_PROP_BOOL("ril", SMMUv3State, ril, true),
> - DEFINE_PROP_BOOL("ats", SMMUv3State, ats, false),
> + DEFINE_PROP_ON_OFF_AUTO("ats", SMMUv3State, ats, ON_OFF_AUTO_AUTO),
> DEFINE_PROP_UINT8("oas", SMMUv3State, oas, 44),
> DEFINE_PROP_UINT8("ssidsize", SMMUv3State, ssidsize, 0),
> };
> @@ -2153,6 +2159,8 @@ static void smmuv3_class_init(ObjectClass *klass, const
> void *data)
> dc->hotpluggable = false;
> dc->user_creatable = true;
>
> + object_class_property_add_bool(klass, "ats-enabled", get_ats_enabled,
> NULL);
> +
> object_class_property_set_description(klass, "accel",
> "Enable SMMUv3 accelerator support. Allows host SMMUv3 to be "
> "configured in nested mode for vfio-pci dev assignment");
> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> index 719d2f994e..6c77fc5f6a 100644
> --- a/hw/arm/virt-acpi-build.c
> +++ b/hw/arm/virt-acpi-build.c
> @@ -402,7 +402,7 @@ static int iort_smmuv3_devices(Object *obj, void *opaque)
>
> bus = PCI_BUS(object_property_get_link(obj, "primary-bus",
> &error_abort));
> sdev.accel = object_property_get_bool(obj, "accel", &error_abort);
> - sdev.ats = object_property_get_bool(obj, "ats", &error_abort);
> + sdev.ats = object_property_get_bool(obj, "ats-enabled", &error_abort);
are we obliged to use a prop here.
we can dynamic cast to the TYPE_ARM_SMMUV3 and use an exported helper, no?
> pbus = PLATFORM_BUS_DEVICE(vms->platform_bus_dev);
> sbdev = SYS_BUS_DEVICE(obj);
> sdev.base = platform_bus_get_mmio_addr(pbus, sbdev, 0);
> diff --git a/include/hw/arm/smmuv3.h b/include/hw/arm/smmuv3.h
> index 26b2fc42fd..2ca49ded36 100644
> --- a/include/hw/arm/smmuv3.h
> +++ b/include/hw/arm/smmuv3.h
> @@ -70,7 +70,7 @@ struct SMMUv3State {
> uint64_t msi_gpa;
> Error *migration_blocker;
> bool ril;
> - bool ats;
> + OnOffAuto ats;
> uint8_t oas;
> uint8_t ssidsize;
> };
Thanks
Eric
