Re: [RFC PATCH v2 08/20] hw/arm/smmuv3-accel: Provide get_address_space callback

[Eric Auger]

Hi Shameer,

On 3/11/25 3:10 PM, Shameer Kolothum wrote:
> Also introduce a struct SMMUv3AccelDevice to hold accelerator specific
> device info. This will be populated accordingly in subsequent patches.
>
> Signed-off-by: Shameer Kolothum <shameerali.kolothum.th...@huawei.com>
> ---
>  hw/arm/smmuv3-accel.c         | 36 +++++++++++++++++++++++++++++++++++
>  include/hw/arm/smmuv3-accel.h |  4 ++++
>  2 files changed, 40 insertions(+)
>
> diff --git a/hw/arm/smmuv3-accel.c b/hw/arm/smmuv3-accel.c
> index 1471b65374..6610ebe4be 100644
> --- a/hw/arm/smmuv3-accel.c
> +++ b/hw/arm/smmuv3-accel.c
> @@ -11,6 +11,40 @@
>  #include "hw/arm/smmuv3-accel.h"
>  #include "hw/pci/pci_bridge.h"
>  
> +static SMMUv3AccelDevice *smmuv3_accel_get_dev(SMMUState *s, SMMUPciBus 
> *sbus,
> +                                                PCIBus *bus, int devfn)
> +{
> +    SMMUDevice *sdev = sbus->pbdev[devfn];
> +    SMMUv3AccelDevice *accel_dev;
> +
> +    if (sdev) {
> +        accel_dev = container_of(sdev, SMMUv3AccelDevice, sdev);
> +    } else {
> +        accel_dev = g_new0(SMMUv3AccelDevice, 1);
> +        sdev = &accel_dev->sdev;
> +
> +        sbus->pbdev[devfn] = sdev;
> +        smmu_init_sdev(s, sdev, bus, devfn);
> +    }
> +
> +    return accel_dev;
> +}
> +
> +static AddressSpace *smmuv3_accel_find_add_as(PCIBus *bus, void *opaque,
> +                                              int devfn)
If you reimplement the ops for the accelerated smmu why did you need to
add:

+++ b/hw/arm/smmu-common.c
@@ -865,6 +865,10 @@ static AddressSpace *smmu_find_add_as(PCIBus *bus, void 
*opaque, int devfn)
     SMMUState *s = opaque;
     SMMUPciBus *sbus = smmu_get_sbus(s, bus);
 
+    if (s->accel && s->get_address_space) {
+        return s->get_address_space(bus, opaque, devfn);
+    }

in 7/20?

Eric

> +{
> +    SMMUState *s = opaque;
> +    SMMUPciBus *sbus;
> +    SMMUv3AccelDevice *accel_dev;
> +    SMMUDevice *sdev;
> +
> +    sbus = smmu_get_sbus(s, bus);
> +    accel_dev = smmuv3_accel_get_dev(s, sbus, bus, devfn);
> +    sdev = &accel_dev->sdev;
> +
> +    return &sdev->as;
> +}
> +
>  static int smmuv3_accel_pxb_pcie_bus(Object *obj, void *opaque)
>  {
>      DeviceState *d = opaque;
> @@ -30,6 +64,7 @@ static void smmu_accel_realize(DeviceState *d, Error **errp)
>      SMMUv3AccelState *s_accel = ARM_SMMUV3_ACCEL(d);
>      SMMUv3AccelClass *c = ARM_SMMUV3_ACCEL_GET_CLASS(s_accel);
>      SysBusDevice *dev = SYS_BUS_DEVICE(d);
> +    SMMUState *bs = ARM_SMMU(d);
>      Error *local_err = NULL;
>  
>      object_child_foreach_recursive(object_get_root(),
> @@ -41,6 +76,7 @@ static void smmu_accel_realize(DeviceState *d, Error **errp)
>          error_propagate(errp, local_err);
>          return;
>      }
> +    bs->get_address_space = smmuv3_accel_find_add_as;
>  }
>  
>  static void smmuv3_accel_class_init(ObjectClass *klass, void *data)
> diff --git a/include/hw/arm/smmuv3-accel.h b/include/hw/arm/smmuv3-accel.h
> index 56fe376bf4..86c0523063 100644
> --- a/include/hw/arm/smmuv3-accel.h
> +++ b/include/hw/arm/smmuv3-accel.h
> @@ -16,6 +16,10 @@
>  #define TYPE_ARM_SMMUV3_ACCEL   "arm-smmuv3-accel"
>  OBJECT_DECLARE_TYPE(SMMUv3AccelState, SMMUv3AccelClass, ARM_SMMUV3_ACCEL)
>  
> +typedef struct SMMUv3AccelDevice {
> +    SMMUDevice  sdev;
> +} SMMUv3AccelDevice;
> +
>  struct SMMUv3AccelState {
>      SMMUv3State smmuv3_state;
>  };