Exynos IOMMU driver doesn't work?

From: Hongbo Zhang <hongbo.zhang-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
To: "iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org"
	<iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>,
	joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org,
	pullip.cho-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org
Cc: Antonios Motakis
	<a.motakis-lrHrjnjw1UfHK3s98zE1ajGjJy/sRE9J@public.gmane.org>
Subject: Exynos IOMMU driver doesn't work?
Date: Wed, 7 Jan 2015 18:31:42 +0800	[thread overview]
Message-ID: <CAOhR-w2vQbyYrWsvZjs-Pt6tU6m9BmH-T5tuBDSyUXteWgxP0Q@mail.gmail.com> (raw)

Hi Cho KyongHo, Joerg et al,
I found the latest Exynos IOMMU driver doesn't work, the line 481:
BUG_ON(!has_sysmmu(dev));
in function __exynos_sysmmu_enable() in file exynos-iommu.c triggers
kernel panic.

Then I found the dev->archdata.iommu isn't initialized at all, it
should be the root cause.

Am I right? any comment, solution?

Another problem is this driver is added support of device tree, but
there is no device tree nodes in the dts file, so I had to search from
internet and added those nodes manually.

I've found these links of v12 and v13 patches
https://lkml.org/lkml/2014/4/27/171
https://lkml.org/lkml/2014/5/12/34
patch v13 was merged into mainline kernel, but as a part of v12, it
isn't complete and doesn't work alone, eg dts nodes are missing.
(I didn't research much dev->archdata.iommu initialization error is
introduced by which patch, but it seems in very old codes there is no
such problem)

Thanks.