Hi Marek, On Thu, Feb 23, 2017 at 11:26 PM, Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> wrote: > Hi Shuah > > > > On 2017-02-23 22:43, Shuah Khan wrote: >> >> On Tue, Feb 14, 2017 at 12:52 AM, Marek Szyprowski >> <m.szyprowski@xxxxxxxxxxx> wrote: >>> >>> It turned out that all versions of MFC v6+ hardware doesn't have a strict >>> requirement for ALL buffers to be allocated on higher addresses than the >>> firmware base like it was documented for MFC v5. This requirement is true >>> only for the device and per-context buffers. All video data buffers can >>> be >>> allocated anywhere for all MFC v6+ versions. Basing on this fact, the >>> special DMA configuration based on two reserved memory regions is not >>> really needed for MFC v6+ devices, because the memory requirements for >>> the >>> firmware, device and per-context buffers can be fulfilled by the simple >>> probe-time pre-allocated block allocator instroduced in previous patch. >>> >>> This patch enables support for such pre-allocated block based allocator >>> always for MFC v6+ devices. Due to the limitations of the memory >>> management >>> subsystem the largest supported size of the pre-allocated buffer when no >>> CMA (Contiguous Memory Allocator) is enabled is 4MiB. >>> >>> This patch also removes the requirement to provide two reserved memory >>> regions for MFC v6+ devices in device tree. Now the driver is fully >>> functional without them. >>> >>> Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> >> >> Hi Marek, >> >> This patch breaks display manager. exynos_drm_gem_create() isn't happy. >> dmesg and console are flooded with >> >> odroid login: [ 209.170566] [drm:exynos_drm_gem_create] *ERROR* failed to >> allo. >> [ 212.173222] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 215.354790] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 218.736464] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 221.837128] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 226.284827] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 229.242498] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 232.063150] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 235.799993] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 239.472061] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 242.567465] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 246.500541] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 249.996018] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 253.837272] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 257.048782] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 260.084819] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 263.448611] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 266.271074] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 269.011558] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 272.039066] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 275.404938] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 278.339033] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 281.274751] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 284.641202] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 287.461039] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 291.062011] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 294.746870] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> [ 298.246570] [drm:exynos_drm_gem_create] *ERROR* failed to allocate >> buffer. >> >> I don't think this is an acceptable behavior. It is a regression. > > > This is a really poor bug report... Could you elaborate a bit how to > reproduce > this? Could you provide your kernel config and information about test > environment? Yeah. I should have give you more information. My bad. > > I suspect that you use CMA without IOMMU and you have too small global CMA > region. Yes. I have CMA and using exynos_defconfig. Nothing fancy. I think what's happening is s5p_mfc pre-allocates and there is nothing left when disaply manager starts requestuing gem buffers. This failure happens when systemd kicks off lightdm. > After this patch MFC driver uses global CMA region instead of the MFC's > private > ones, so one has to ensure that the global region is large enough. This is still a regression since it requires users to take some action. I think we need some kind of checks to warn users there isn't a large enough CMA region. This is the same config I have been using forever and with this patch, it breaks. Easy to reproduce on odroid-xu4 with HDMI display. You just have to boot the system with exynos_defconfig. Display manager will fail when it requests buffers. thanks, -- Shuah > >> [...] > > > Best regards > -- > Marek Szyprowski, PhD > Samsung R&D Institute Poland >
