> -----Original Message----- > From: Will Deacon [mailto:[email protected]] > Sent: Wednesday, January 22, 2014 5:56 PM > To: Sethi Varun-B16395 > Cc: Andreas Herrmann; [email protected]; linux-arm- > [email protected]; Andreas Herrmann > Subject: Re: [PATCH v3 02/11] iommu/arm-smmu: Introduce iommu_group > notifier block > > Hi Varun, Andreas, > > On Tue, Jan 21, 2014 at 05:48:02PM +0000, Varun Sethi wrote: > > > +static int arm_smmu_group_notifier(struct notifier_block *nb, > > > + unsigned long action, void *data) { > > > + struct device *dev = data; > > > + struct dma_iommu_mapping *mapping; > > > + struct arm_smmu_device *smmu; > > > + int ret; > > > + > > > + switch (action) { > > > + case IOMMU_GROUP_NOTIFY_BIND_DRIVER: > > > + > > > + smmu = dev->archdata.iommu; > > > + if (!smmu || !(smmu->options & ARM_SMMU_OPT_ISOLATE_DEVICES)) > > > + break; > > [Sethi Varun-B16395] Should this check be really done here? The > > "Isolate devices" property would allow us to set up iommu groups. My > > understanding is that if we specify the isolate devices property, then > > each device would have a separate iommu group otherwise all devices > > connected to the SMMU would share the iommu group. > > That's not what currently happens (at least, in the patch I have queued > for groups). The code queued adds each device to its own group in > arm_smmu_add_device, which I think is the right thing to do. > > > With that logic, we should link the mapping to the iommu group. > > Ok, so are you suggesting that we perform the isolation mapping in > arm_smmu_add_device and drop the notifier altogether? I think that should be fine, until we want to delay mapping creation till driver bind time. But the "isolate device" property should dictate iommu group creation.
-Varun _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
