On Sun, Dec 10, 2023 at 10:06:53AM -0800, Rob Clark wrote: > From: Rob Clark <robdclark@xxxxxxxxxxxx> > > In some cases the firmware expects cbndx 1 to be assigned to the GMU, > so we also want the default domain for the GMU to be an identy domain. > This way it does not get a context bank assigned. Without this, both > of_dma_configure() and drm/msm's iommu_domain_attach() will trigger > allocating and configuring a context bank. So GMU ends up attached to > both cbndx 1 and later cbndx 2. This arrangement seemingly confounds > and surprises the firmware if the GPU later triggers a translation > fault, resulting (on sc8280xp / lenovo x13s, at least) in the SMMU > getting wedged and the GPU stuck without memory access. > > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx> Tested-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
