Hello,
On 2015-05-11 18:00, Javier Martinez Canillas wrote:
Hello Marek,
On Mon, May 4, 2015 at 10:15 AM, Marek Szyprowski
<m.szyprowski@xxxxxxxxxxx> wrote:
Hello Everyone,
This is yet another attempt to get Exynos SYSMMU driver with integrated
with IOMMU & DMA-mapping subsystems. The main change from previous
version is addition of the patches to define iommu-mapping, which need
to be created during system boot to avoid IOMMU fault by devices, which
has been left enabled by bootloader (i.e. framebuffer displaying slash
screen).
Patches has been also rebased onto v4.1-rc2 with 'arm: dma-mapping: fix
off-by-one check in arm_setup_iommu_dma_ops' patch applied (see commit
1424532b2163bf1580f4b1091a5801e12310fac5 on fixes branch in
git://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-arm.git,
more information:
http://www.spinics.net/lists/arm-kernel/msg414722.html).
All patches are also available in the following git repository:
https://git.linaro.org/people/marek.szyprowski/linux-srpol.git
branch v4.1-exynos-iommu.
Thanks for the new series, this time I didn't get a system hang when I
enabled both CONFIG_DRM_EXYNOS_FIMD and CONFIG_DRM_EXYNOS_DP on my
Exynos5420 Peach Pit Chromebook.
The system finished booting and I have both a console on the HDMI and
eDP/LVDS displays. But if I try to start X or weston, I again have a
completele system hang with no output on the serial console. This
works correctly without your IOMMU series.
And again disabling CONFIG_DRM_EXYNOS_DP or CONFIG_DRM_EXYNOS_FIMD
avoids the system to hang. If I only have CONFIG_DRM_EXYNOS_HDMI
enabled, then I can start X with out issues and is displayed correctly
in the HDMI output.
So it seems your workaround for the boot-loader leaving the FIMD dma
engine enabled is not enough? I'm not a graphics person so I can think
of the top of my head what could trigger the system hang when X or
weston are executed so I wondered if you have any ideas.
This means that there are more bugs in Exynos DRM driver. Once Exynos DRM
driver is probed, the initial iommu domain with identity mapping is
destroyed
and Exynos DRM manages it's own iommu domain, so it has nothing to my
mentioned patch.
I will try to check this issue.
Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland
--
To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
