On 7/7/2026 10:09 PM, Dmitry Baryshkov wrote: > On Tue, Jul 07, 2026 at 05:02:43PM +0200, Anna Maniscalco wrote: >> On 7/6/26 5:04 PM, Dmitry Baryshkov wrote: >>> On Sun, Jul 05, 2026 at 09:13:37PM +0200, Anna Maniscalco wrote: >>>> In order to associate the SID used by LPAC to it's own domain and >>>> context bank we need a separate node on the DTS. >>> Can we use iommu-map instead of adding a new device using the same >>> addresses? You provide zero explanations, but it seems like you are >>> trying to separate a part of the GPU into a separate device, but it's >>> unnecessary. >> >> What I was trying to say is that we need to map sid0 and sid1 to different >> context banks. >> >> From what I recall, so long as we use the same dt node, the iommu drivert >> provides no way of doing this. >> >> What kgsl does is having a node for the iommu and then subnodes for gfx lpac >> and secure. >> >> The address on the lpac device doesn't really matter. I have very limted >> knowledge of DTSs but I think we could just leave it out altogether? > > I think, you were poined to the Glymur Iris patches. Another option is > the QDA driver being submitted too. Both ot them use iommu-map to > describe the same usecase - a set of SIDs which are used by the device > but which should not be a part of the defaut set. With it in place you > don't need to have separate qcom,lpac devices, no additional properties, > etc. > > I'd recommend following the same approach.
iiuc, the conclusion in this recent thread is to use child nodes for a similar case: https://lore.kernel.org/all/[email protected]/ -Akhil > >> >>> >>>> Add the code to look up that node on initialization. >>>> >>>> Signed-off-by: Anna Maniscalco <[email protected]> >>>> --- >>>> drivers/gpu/drm/msm/adreno/adreno_gpu.c | 21 ++++++++++++++++++++- >>>> drivers/gpu/drm/msm/msm_gpu.h | 1 + >>>> 2 files changed, 21 insertions(+), 1 deletion(-) >>>> >> >> Best regards, >> -- >> Anna Maniscalco <[email protected]> >> >
