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

Ashish Mhetre amhetre at nvidia.com
Wed Jul 8 07:12:21 PDT 2026



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.
Shall I respin v5 that uses only static key and drops the option bit 
completely?

Thanks,
Ashish Mhetre

> Nicolin




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