On Tue 30 Mar 10:31 CDT 2021, Will Deacon wrote: > On Tue, Mar 30, 2021 at 08:03:36AM -0700, Rob Clark wrote: > > On Tue, Mar 30, 2021 at 2:34 AM Will Deacon <will@xxxxxxxxxx> wrote: > > > > > > On Mon, Mar 29, 2021 at 09:02:50PM -0700, Rob Clark wrote: > > > > On Mon, Mar 29, 2021 at 7:47 AM Will Deacon <will@xxxxxxxxxx> wrote: > > > > > > > > > > On Fri, Mar 26, 2021 at 04:13:02PM -0700, Eric Anholt wrote: > > > > > > db820c wants to use the qcom smmu path to get HUPCF set (which keeps > > > > > > the GPU from wedging and then sometimes wedging the kernel after a > > > > > > page fault), but it doesn't have separate pagetables support yet in > > > > > > drm/msm so we can't go all the way to the TTBR1 path. > > > > > > > > > > What do you mean by "doesn't have separate pagetables support yet"? The > > > > > compatible string doesn't feel like the right way to determine this. > > > > > > > > the compatible string identifies what it is, not what the sw > > > > limitations are, so in that regard it seems right to me.. > > > > > > Well it depends on what "doesn't have separate pagetables support yet" > > > means. I can't tell if it's a hardware issue, a firmware issue or a driver > > > issue. > > > > Just a driver issue (and the fact that currently we don't have > > physical access to a device... debugging a5xx per-process-pgtables by > > pushing untested things to the CI farm is kind of a difficult way to > > work) > > But then in that case, this is using the compatible string to identify a > driver issue, no? > No the compatible addition identifies the hardware, the implementation then uses this information to know that it needs to behave "differently" on this platform. When/if someone decides to add the necessary support in the driver they can remove the driver quirk, but it doesn't invalidate the specific compatible. Regards, Bjorn
