On 3/12/26 10:03 PM, Nathan Chen wrote:
> From: Nathan Chen <nathanc@nvidia.com>
>
> Introduce a new enum type property allowing to set a Substream ID size
> for HW-accelerated smmuv3. Values are auto and 0..20. The auto value
> allows SSID size property to be derived from host IOMMU capabilities.
> A value of 0 disables SubstreamID, while non-zero values specify the
> SSID size in bits.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Eric
>
> Signed-off-by: Nathan Chen <nathanc@nvidia.com>
> ---
> hw/core/qdev-properties-system.c | 14 ++++++++++++++
> include/hw/core/qdev-properties-system.h | 3 +++
> qapi/misc-arm.json | 16 ++++++++++++++++
> qapi/pragma.json | 1 +
> 4 files changed, 34 insertions(+)
>
> diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c
> index a402321f42..4aca1d4326 100644
> --- a/hw/core/qdev-properties-system.c
> +++ b/hw/core/qdev-properties-system.c
> @@ -18,6 +18,7 @@
> #include "qapi/qapi-types-block.h"
> #include "qapi/qapi-types-machine.h"
> #include "qapi/qapi-types-migration.h"
> +#include "qapi/qapi-types-misc-arm.h"
> #include "qapi/qapi-visit-virtio.h"
> #include "qapi/qmp/qerror.h"
> #include "qemu/ctype.h"
> @@ -723,6 +724,19 @@ const PropertyInfo qdev_prop_zero_page_detection = {
> .set_default_value = qdev_propinfo_set_default_value_enum,
> };
>
> +/* --- SsidSizeMode --- */
> +
> +QEMU_BUILD_BUG_ON(sizeof(SsidSizeMode) != sizeof(int));
> +
> +const PropertyInfo qdev_prop_ssidsize_mode = {
> + .type = "SsidSizeMode",
> + .description = "ssidsize mode: auto, 0-20",
> + .enum_table = &SsidSizeMode_lookup,
> + .get = qdev_propinfo_get_enum,
> + .set = qdev_propinfo_set_enum,
> + .set_default_value = qdev_propinfo_set_default_value_enum,
> +};
> +
> /* --- Reserved Region --- */
>
> /*
> diff --git a/include/hw/core/qdev-properties-system.h b/include/hw/core/qdev-properties-system.h
> index ec21732ce5..4708885164 100644
> --- a/include/hw/core/qdev-properties-system.h
> +++ b/include/hw/core/qdev-properties-system.h
> @@ -14,6 +14,7 @@ extern const PropertyInfo qdev_prop_multifd_compression;
> extern const PropertyInfo qdev_prop_mig_mode;
> extern const PropertyInfo qdev_prop_granule_mode;
> extern const PropertyInfo qdev_prop_zero_page_detection;
> +extern const PropertyInfo qdev_prop_ssidsize_mode;
> extern const PropertyInfo qdev_prop_losttickpolicy;
> extern const PropertyInfo qdev_prop_blockdev_on_error;
> extern const PropertyInfo qdev_prop_bios_chs_trans;
> @@ -61,6 +62,8 @@ extern const PropertyInfo qdev_prop_virtio_gpu_output_list;
> #define DEFINE_PROP_ZERO_PAGE_DETECTION(_n, _s, _f, _d) \
> DEFINE_PROP_SIGNED(_n, _s, _f, _d, qdev_prop_zero_page_detection, \
> ZeroPageDetection)
> +#define DEFINE_PROP_SSIDSIZE_MODE(_n, _s, _f, _d) \
> + DEFINE_PROP_SIGNED(_n, _s, _f, _d, qdev_prop_ssidsize_mode, SsidSizeMode)
> #define DEFINE_PROP_LOSTTICKPOLICY(_n, _s, _f, _d) \
> DEFINE_PROP_SIGNED(_n, _s, _f, _d, qdev_prop_losttickpolicy, \
> LostTickPolicy)
> diff --git a/qapi/misc-arm.json b/qapi/misc-arm.json
> index f921d740f1..76ea0a09fa 100644
> --- a/qapi/misc-arm.json
> +++ b/qapi/misc-arm.json
> @@ -45,3 +45,19 @@
> # { "version": 3, "emulated": false, "kernel": true } ] }
> ##
> { 'command': 'query-gic-capabilities', 'returns': ['GICCapability'] }
> +
> +##
> +# @SsidSizeMode:
> +#
> +# SMMUv3 SubstreamID size configuration mode.
> +#
> +# @auto: derive from host IOMMU capabilities
> +#
> +# Values 0-20: SSIDSIZE value in bits. 0 disables SubstreamID.
> +#
> +# Since: 11.0
> +##
> +{ 'enum': 'SsidSizeMode',
> + 'data': [ 'auto', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
> + '10', '11', '12', '13', '14', '15', '16', '17', '18',
> + '19', '20' ] } # order matters, see ssid_size_mode_auto()
> diff --git a/qapi/pragma.json b/qapi/pragma.json
> index 193bc39059..24aebbe8f5 100644
> --- a/qapi/pragma.json
> +++ b/qapi/pragma.json
> @@ -68,6 +68,7 @@
> 'S390CpuEntitlement',
> 'S390CpuPolarization',
> 'S390CpuState',
> + 'SsidSizeMode',
> 'String',
> 'StringWrapper',
> 'SysEmuTarget',