[PATCH 1/4] iommu/arm-smmu-v3: Work around MMU-600 erratum 1076982

[Robin Murphy]

On 2023-05-10 18:40, Nicolin Chen wrote:
> On Wed, May 10, 2023 at 04:38:43PM +0100, Robin Murphy wrote:
> 
>> MMU-600 versions prior to r1p0 fail to correctly generate a WFE wakeup
>> event when the command queue transitions fom full to non-full. We can
>> easily work around this by simply hiding the SEV capability such that we
>> fall back to polling for space in the queue - since MMU-600 implements
>> MSIs we wouldn't expect to need SEV for sync completion either, so this
>> should have little to no impact.
>>
>> Signed-off-by: Robin Murphy <robin.murphy at arm.com>
> 
> Reviewed-by: Nicolin Chen <nicolinc at nvidia.com>

Thanks!

>> +static void arm_smmu_device_iidr_probe(struct arm_smmu_device *smmu)
>> +{
>> +       u32 reg;
>> +       unsigned int implementer, productid, variant, revision;
> 
> Just for curiosity -- what's the fashion behind the coding style
> here? Usually I follow a longer-to-shorter style, yet perhaps I
> can follow this one for further SMMU patches, if it matters.

In the case of my code, it's usually some intuitive contextual order 
based on a hierarchy of the types and/or importance of variables within 
the logic of the function and relative to each other. I couldn't really 
explain it as a set of rules, it's just whatever feels most right :)

Cheers,
Robin.