[PATCH v4 2/3] iommu/arm-smmu-v3: Detect Tegra264 erratum

Nicolin Chen nicolinc at nvidia.com
Wed Jul 8 17:52:31 PDT 2026


On Wed, Jul 08, 2026 at 07:42:21PM +0530, Ashish Mhetre wrote:
> On 7/8/2026 4:55 AM, Nicolin Chen wrote:
> > On Tue, Jun 09, 2026 at 07:32:03AM +0000, Ashish Mhetre wrote:
> > > +arm_smmu_erratum_cmd_needs_repeating(struct arm_smmu_device *smmu,
> > > +				     struct arm_smmu_cmd *cmd)
> > > +{
> > [...]
> > > +	if (!static_branch_unlikely(&arm_smmu_erratum_repeat_tlbi_cfgi_key))
> > > +		return false;
> > > +	if (!(smmu->options & ARM_SMMU_OPT_REPEAT_TLBI_CFGI))
> > > +		return false;
> > Are they redundant?
> 
> Yes, both are set together in exactly one place, arm_smmu_device_dt_probe(),
> guarded by the same "nvidia,tegra264-smmu" compatible check.
> If we want to go with static key, then that makes option bit completely
> useless.

Drop the deadcode then.

Nicolin



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