Hi Olav, On Mon, Aug 04, 2014 at 07:01:03PM +0100, Olav Haugan wrote: > The SMR registers do not exist when stream matching is not > supported by the hardware. Avoid writing to this register if not needed. > > Signed-off-by: Olav Haugan <[email protected]> > --- > drivers/iommu/arm-smmu.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c > index c16431f..1f3a5b3 100644 > --- a/drivers/iommu/arm-smmu.c > +++ b/drivers/iommu/arm-smmu.c > @@ -1731,7 +1731,10 @@ static void arm_smmu_device_reset(struct > arm_smmu_device *smmu) > > /* Mark all SMRn as invalid and all S2CRn as bypass */ > for (i = 0; i < smmu->num_mapping_groups; ++i) { > - writel_relaxed(~SMR_VALID, gr0_base + ARM_SMMU_GR0_SMR(i)); > + if (smmu->features & ARM_SMMU_FEAT_STREAM_MATCH) { > + writel_relaxed(~SMR_VALID, > + gr0_base + ARM_SMMU_GR0_SMR(i)); > + } > writel_relaxed(S2CR_TYPE_BYPASS, > gr0_base + ARM_SMMU_GR0_S2CR(i));
smmu->num_mapping_groups should be zero for an SMMU that doesn't include the SMR registers, so I don't think this change is needed. Are you seeing problems with real hardware? Will _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
