Hi Shuah,
On 2017-02-24 15:23, Shuah Khan wrote:
On Thu, Feb 23, 2017 at 11:26 PM, Marek Szyprowski
<m.szyprowski@xxxxxxxxxxx> wrote:
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.
That is still a bit strange. MFC pre-allocates 8MiB buffer. The default CMA
global region size is 64MiB, which should be enough for a few display
buffers.
It looks that your display manager consumes quite a lot of memory and it
already almost hits the limit from the exynos_defconfig.
It should be safe to increase default CMA region size to 80MiB or even 96MiB
in the exynos_defconfig to avoid such problem.
Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland
