This reverts commit e2a88eabb02410267519b838fb9b79f5206769be. The commit in question makes msm_use_mmu() check whether the DRM 'component master' device is translated by the IOMMU. At this moment it is the 'mdss' device. However on platforms using the MDP5 driver (e.g. MSM8916/APQ8016, MSM8996/APQ8096) it's the mdp5 device, which has the iommus property (and thus is "translated by the IOMMU"). This results in these devices being broken with the following lines in the dmesg. [drm] Initialized msm 1.9.0 20130625 for 1a00000.mdss on minor 0 msm 1a00000.mdss: [drm:adreno_request_fw] loaded qcom/a300_pm4.fw from new location msm 1a00000.mdss: [drm:adreno_request_fw] loaded qcom/a300_pfp.fw from new location msm 1a00000.mdss: [drm:get_pages] *ERROR* could not get pages: -28 msm 1a00000.mdss: could not allocate stolen bo msm 1a00000.mdss: [drm:get_pages] *ERROR* could not get pages: -28 msm 1a00000.mdss: [drm:msm_alloc_stolen_fb] *ERROR* failed to allocate buffer object msm 1a00000.mdss: [drm:msm_fbdev_create] *ERROR* failed to allocate fb Getting the mdp5 device pointer from this function is not that easy at this moment. Thus this patch is reverted till the MDSS rework [1] lands. It will make the mdp5/dpu1 device component master and the check will be legit. [1] https://patchwork.freedesktop.org/series/98525/ Fixes: e2a88eabb024 ("drm/msm: Stop using iommu_present()") Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Link: https://lore.kernel.org/r/20220419130422.1033699-1-dmitry.baryshkov@linaro.org Signed-off-by: Rob Clark <robdclark@chromium.org>
Linux kernel ============ There are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. Please read Documentation/admin-guide/README.rst first. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. The formatted documentation can also be read online at: https://www.kernel.org/doc/html/latest/ There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.
Description
Languages
C
97.6%
Assembly
1%
Shell
0.5%
Python
0.3%
Makefile
0.3%