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iommu/tegra-smmu: Make tegra_smmu_probe_device() to handle all IOMMU phandles

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@gmail.com>
Tested-by: Nicolin Chen <nicoleotsuka@gmail.com>
Link: https://lore.kernel.org/r/20210312155439.18477-1-digetx@gmail.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

authored by

Dmitry Osipenko and committed by
Joerg Roedel
8dfd0fa6 4b8ef157

+3 -4
+3 -4
drivers/iommu/tegra-smmu.c
··· 849 849 smmu = tegra_smmu_find(args.np); 850 850 if (smmu) { 851 851 err = tegra_smmu_configure(smmu, dev, &args); 852 - of_node_put(args.np); 853 852 854 - if (err < 0) 853 + if (err < 0) { 854 + of_node_put(args.np); 855 855 return ERR_PTR(err); 856 - 857 - break; 856 + } 858 857 } 859 858 860 859 of_node_put(args.np);