On 15/11/2022 12:11, AngeloGioacchino Del Regno wrote:
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@xxxxxxxxxxxxxx> [Marijn: Rebased over next-20221111] Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx> --- drivers/iommu/arm/arm-smmu/qcom_iommu.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-)
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> -- With best wishes Dmitry
