[PATCH v5 00/18] Exynos SYSMMU (IOMMU) integration with DT and DMA-mapping subsystem

[Javier Martinez Canillas]

Hello Marek,

On Wed, Feb 4, 2015 at 3:21 PM, Joerg Roedel <joro at 8bytes.org> wrote:
> Hi Marek,
>
> On Fri, Jan 23, 2015 at 04:51:10PM +0100, Marek Szyprowski wrote:
>> 1. All iommu related patches (with 'iommu: exynos') can be merged to
>> iommu tree. They don't have any direct dependencies on the DTS, DRM and
>> power domain initialization change - without them the driver will simply
>> not initialize, when no exynos,sysmmu nodes are provided in device tree.
>>
>> Joerg, could you merge those patches?
>
> Given the previous comments and tests on this patch set I am still
> waiting for some Acked-bys and/or Tested-bys on this. Can you collect
> these and resend then (probably after the v3.20 merge window)?
>

I rebased your patches on top of latest linux-next (next-20150415) and
tested it on my Exynos5420 Peach Pit. HDMI display is working
correctly (both console and X) when CONFIG_DRM_EXYNOS_IOMMU is
enabled. I also see that the mixer is attached to the IOMMU domain:

exynos-mixer 14450000.mixer: exynos_iommu_attach_device: Attached
IOMMU with pgtable 0x6e5e0000
...
exynos-sysmmu 14650000.sysmmu: Enabled

As I mentioned before [0] on your v4 series, I still have the boot
hang when CONFIG_DRM_EXYNOS_FIMD is enabled. You said that the cause
is u-boot leaving the FIMD DMA engine enabled and so causing IOMMU
page faults on init [1].

I tried disabling the display on u-boot but the system hangs remains.
But since I do a chain loading using the verified u-boot that comes
with the Chromebooks, I don't know if the RO boot-loader is leaving
something enabled.

In any case since HDMI with sysmmu is working correctly, that issue is
orthogonal to your series and can be fixed as a followup so:

Tested-by: Javier Martinez Canillas <javier.martinez at collabora.co.uk>

NOTE: Most of the patches don't apply cleanly so I pushed a branch [2]
with my conflict resolution so you don't have to do the same. I also
did some small changes like using bool instead of int when were
assigning it to true and renaming some of the subject lines to match
the format used by the subsystem.

What I didn't change is to re-order the sysmmu device nodes according
to the unit address that was asked by Andreas since the DTS patches
are likely to conflict with the work Krzysztof is doing to use labels
instead of overriding nodes in Exynos 4 and 5 DTS[i]. So you may need
to change those anyways once Krzysztof patches land.

Best regards,
Javier

[0]: http://lists.infradead.org/pipermail/linux-arm-kernel/2015-January/317727.html
[1]: http://lists.infradead.org/pipermail/linux-arm-kernel/2015-January/319178.html
[2]: http://cgit.collabora.com/git/user/javier/linux.git/log/?h=next20150415-exynos-iommu