On 23.10.19 г. 16:39 ч., Georgi Djakov wrote: > On 23.10.19 г. 15:47 ч., Brian Masney wrote: >> On Wed, Oct 23, 2019 at 02:50:19PM +0300, Georgi Djakov wrote: >>> On 13.10.19 г. 11:08 ч., Brian Masney wrote: >>>> Add interconnect nodes that's needed to support bus scaling. >>>> >>>> Signed-off-by: Brian Masney <masneyb@xxxxxxxxxxxxx> >>>> --- >>>> arch/arm/boot/dts/qcom-msm8974.dtsi | 60 +++++++++++++++++++++++++++++ >>>> 1 file changed, 60 insertions(+) >>>> >>>> diff --git a/arch/arm/boot/dts/qcom-msm8974.dtsi b/arch/arm/boot/dts/qcom-msm8974.dtsi >>>> @@ -1152,6 +1207,11 @@ >>>> "core", >>>> "vsync"; >>>> >>>> + interconnects = <&mmssnoc MNOC_MAS_GRAPHICS_3D &bimc BIMC_SLV_EBI_CH0>, >>>> + <&ocmemnoc OCMEM_VNOC_MAS_GFX3D &ocmemnoc OCMEM_SLV_OCMEM>; >>> >>> Who will be the requesting bandwidth to DDR and ocmem? Is it the display or GPU >>> or both? The above seem like GPU-related interconnects, so maybe these >>> properties should be in the GPU DT node. >> >> The display is what currently requests the interconnect path, >> specifically mdp5_setup_interconnect() in >> drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c. The Freedreno GPU bindings >> currently don't have interconnect support. Maybe this is something that >> I should add to that driver as well? > > The "mdp0-mem" and "mdp1-mem" paths mentioned in the mdp5_kms.c are the two > interconnects between the display and DDR memory. There is actually a patch [1] > to add to GPU bindings, but it seems that we missed to pick it up. It was actually merged in v5.2. BR, Georgi >>>> + interconnect-names = "mdp0-mem", >>>> + "mdp1-mem"; >>> >>> As the second path is not to DDR, but to ocmem, it might be better to call it >>> something like "gpu-ocmem". >> >> I used what mdp5_kms.c expected. > > This is for the display and here [2] are some patches for the GPU. Not sure how > the NoCs are configured on 8974 by default, but if you notice any blue/black > screens, you may need to request bandwidth for display too. > > Thanks, > Georgi > > [1] > https://lore.kernel.org/r/1555703787-10897-1-git-send-email-jcrouse@xxxxxxxxxxxxxx > [2] https://lore.kernel.org/r/20181220173026.3857-1-jcrouse@xxxxxxxxxxxxxx >
