822a2ed8c6
When the iommu master device enters of_iommu_xlate, the ops may be
NULL(iommu dev is defered), then it will initialize the fwspec here:
[<c0c9c5bc>] (dev_iommu_fwspec_set) from [<c06bda80>]
(iommu_fwspec_init+0xbc/0xd4)
[<c06bd9c4>] (iommu_fwspec_init) from [<c06c0db4>]
(of_iommu_xlate+0x7c/0x12c)
[<c06c0d38>] (of_iommu_xlate) from [<c06c10e8>]
(of_iommu_configure+0x144/0x1e8)
BUT the mtk_iommu_v1.c only supports arm32, the probing flow still is a bit
weird. We always expect create the fwspec internally. otherwise it will
enter here and return fail.
static int mtk_iommu_create_mapping(struct device *dev,
struct of_phandle_args *args)
{
...
if (!fwspec) {
....
} else if (dev_iommu_fwspec_get(dev)->ops != &mtk_iommu_ops) {
>>>>>>>>>>Enter here. return fail.<<<<<<<<<<<<
return -EINVAL;
}
...
}
Thus, Free the existed fwspec if the master device already has fwspec.
This issue is reported at:
https://lore.kernel.org/linux-mediatek/trinity-7d9ebdc9-4849-4d93-bfb5-429dcb4ee449-1626253158870@3c-app-gmx-bs01/
Reported-by: Frank Wunderlich <frank-w@public-files.de>
Tested-by: Frank Wunderlich <frank-w@public-files.de> # BPI-R2/MT7623
Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
Acked-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.