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e30c960d3f
On some SoCs like MSM8956, MSM8976 and others, secure contexts are also secured: these get programmed by the bootloader or TZ (as usual) but their "interesting" registers are locked out by the hypervisor, disallowing direct register writes from Linux and, in many cases, completely disallowing the reprogramming of TTBR, TCR, MAIR and other registers including, but not limited to, resetting contexts. This is referred downstream as a "v2" IOMMU but this is effectively a "v2 firmware configuration" instead. Luckily, the described behavior of version 2 is effective only on secure contexts and not on non-secure ones: add support for that, finally getting a completely working IOMMU on at least MSM8956/76. Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org> [Marijn: Rebased over next-20221111] Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org> Link: https://lore.kernel.org/r/20230622092742.74819-7-angelogioacchino.delregno@collabora.com Signed-off-by: Will Deacon <will@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.