This is a note to let you know that I've just added the patch titled iommu/tegra-smmu: Make tegra_smmu_probe_device() to handle all IOMMU phandles to the 5.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: iommu-tegra-smmu-make-tegra_smmu_probe_device-to-handle-all-iommu-phandles.patch and it can be found in the queue-5.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 8dfd0fa6ecdc5e2099a57d485b7ce237abc6c7a0 Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko <digetx@xxxxxxxxx> Date: Fri, 12 Mar 2021 18:54:39 +0300 Subject: iommu/tegra-smmu: Make tegra_smmu_probe_device() to handle all IOMMU phandles From: Dmitry Osipenko <digetx@xxxxxxxxx> commit 8dfd0fa6ecdc5e2099a57d485b7ce237abc6c7a0 upstream. The tegra_smmu_probe_device() handles only the first IOMMU device-tree phandle, skipping the rest. Devices like 3D module on Tegra30 have multiple IOMMU phandles, one for each h/w block, and thus, only one IOMMU phandle is added to fwspec for the 3D module, breaking GPU. Previously this problem was masked by tegra_smmu_attach_dev() which didn't use the fwspec, but parsed the DT by itself. The previous commit to tegra-smmu driver partially reverted changes that caused problems for T124 and now we have tegra_smmu_attach_dev() that uses the fwspec and the old-buggy variant of tegra_smmu_probe_device() which skips secondary IOMMUs. Make tegra_smmu_probe_device() not to skip the secondary IOMMUs. This fixes a partially attached IOMMU of the 3D module on Tegra30 and now GPU works properly once again. Fixes: 765a9d1d02b2 ("iommu/tegra-smmu: Fix mc errors on tegra124-nyan") Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx> Tested-by: Nicolin Chen <nicoleotsuka@xxxxxxxxx> Link: https://lore.kernel.org/r/20210312155439.18477-1-digetx@xxxxxxxxx Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/iommu/tegra-smmu.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) --- a/drivers/iommu/tegra-smmu.c +++ b/drivers/iommu/tegra-smmu.c @@ -849,12 +849,11 @@ static struct iommu_device *tegra_smmu_p smmu = tegra_smmu_find(args.np); if (smmu) { err = tegra_smmu_configure(smmu, dev, &args); - of_node_put(args.np); - if (err < 0) + if (err < 0) { + of_node_put(args.np); return ERR_PTR(err); - - break; + } } of_node_put(args.np); Patches currently in stable-queue which might be from digetx@xxxxxxxxx are queue-5.11/iommu-tegra-smmu-make-tegra_smmu_probe_device-to-handle-all-iommu-phandles.patch