On Tue, Aug 27, 2024 at 04:57:48PM +0100, Robin Murphy wrote:
> > > @@ -4341,18 +4341,28 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> > > }
> > >
> > > #ifdef CONFIG_ACPI
> > > -static void acpi_smmu_get_options(u32 model, struct arm_smmu_device *smmu)
> > > +static int acpi_smmu_iort_probe_model(struct acpi_iort_node *node,
> > > + struct arm_smmu_device *smmu)
> > > {
> > > - switch (model) {
> > > + struct acpi_iort_smmu_v3 *iort_smmu =
> > > + (struct acpi_iort_smmu_v3 *)node->node_data;
> > > +
> > > + switch (iort_smmu->model) {
> > > case ACPI_IORT_SMMU_V3_CAVIUM_CN99XX:
> > > smmu->options |= ARM_SMMU_OPT_PAGE0_REGS_ONLY;
> > > break;
> > > case ACPI_IORT_SMMU_V3_HISILICON_HI161X:
> > > smmu->options |= ARM_SMMU_OPT_SKIP_PREFETCH;
> > > break;
> > > + case ACPI_IORT_SMMU_V3_GENERIC:
> > > + break;
> > > + default:
> > > + dev_err(smmu->dev, "Unknown/unsupported IORT model!\n");
> > > + return -ENXIO;
> >
> > We probably don't want this 'default' case, otherwise the driver will
> > need to be updated every time there's a new model.
>
> ...although the intent is very strongly that there should never be any
> new models, because by now hardware should really not be failing to
> implement SMMU_IIDR correctly. In some ways, having this might help
> further discourage people from abusing the mechanism and making random
> stuff up in their firmware :/
I don't have a strong feeling about this, though Robin's point was
my intention here.
Apart from this "default case", I typo-ed the function name in the
patch subject and commit message. Also, there's a missed kdoc line
in struct tegra241_cmdqv (PATCH-8).
So, I prepared a v14:
https://github.com/nicolinc/iommufd/commits/vcmdq_in_kernel-v14
v14 changelog (attaching git-diff at the EOM):
* Rebased on Will's for-joerg/arm-smmu/updates
* Added a missed kdoc for "dev" in struct tegra241_cmdqv
* Dropped the default case in acpi_smmu_iort_probe_model()
(did this before seeing Robin's mail here.)
Let's see what makes the best for you, Will.
Thanks
Nicolin
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 8b1437240ce5..f23245012681 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -4356,9 +4356,6 @@ static int acpi_smmu_iort_probe_model(struct acpi_iort_node *node,
break;
case ACPI_IORT_SMMU_V3_GENERIC:
break;
- default:
- dev_err(smmu->dev, "Unknown/unsupported IORT model!\n");
- return -ENXIO;
}
dev_notice(smmu->dev, "option mask 0x%x\n", smmu->options);
diff --git a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
index b794a4dcbce1..5ac3032ee6dd 100644
--- a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
+++ b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
@@ -160,6 +160,7 @@ struct tegra241_vintf {
/**
* struct tegra241_cmdqv - CMDQ-V for SMMUv3
* @smmu: SMMUv3 device
+ * @dev: CMDQV device
* @base: MMIO base address
* @irq: IRQ number
* @num_vintfs: Total number of VINTFs
