Commit ec615f43 authored by Robin Murphy's avatar Robin Murphy Committed by Joerg Roedel

iommu/arm-smmu: Don't inadvertently reject multiple SMMUv3s

We now delay installing our per-bus iommu_ops until we know an SMMU has
successfully probed, as they don't serve much purpose beforehand, and
doing so also avoids fights between multiple IOMMU drivers in a single
kernel. However, the upshot of passing the return value of bus_set_iommu()
back from our probe function is that if there happens to be more than
one SMMUv3 device in a system, the second and subsequent probes will
wind up returning -EBUSY to the driver core and getting torn down again.

Avoid re-setting ops if ours are already installed, so that any genuine
failures stand out.

Fixes: 08d4ca2a ("iommu/arm-smmu: Support non-PCI devices with SMMUv3")
CC: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
CC: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: default avatarRobin Murphy <robin.murphy@arm.com>
Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent fba4f8e5
...@@ -2636,17 +2636,26 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev) ...@@ -2636,17 +2636,26 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev)
/* And we're up. Go go go! */ /* And we're up. Go go go! */
of_iommu_set_ops(dev->of_node, &arm_smmu_ops); of_iommu_set_ops(dev->of_node, &arm_smmu_ops);
#ifdef CONFIG_PCI #ifdef CONFIG_PCI
if (pci_bus_type.iommu_ops != &arm_smmu_ops) {
pci_request_acs(); pci_request_acs();
ret = bus_set_iommu(&pci_bus_type, &arm_smmu_ops); ret = bus_set_iommu(&pci_bus_type, &arm_smmu_ops);
if (ret) if (ret)
return ret; return ret;
}
#endif #endif
#ifdef CONFIG_ARM_AMBA #ifdef CONFIG_ARM_AMBA
if (amba_bustype.iommu_ops != &arm_smmu_ops) {
ret = bus_set_iommu(&amba_bustype, &arm_smmu_ops); ret = bus_set_iommu(&amba_bustype, &arm_smmu_ops);
if (ret) if (ret)
return ret; return ret;
}
#endif #endif
return bus_set_iommu(&platform_bus_type, &arm_smmu_ops); if (platform_bus_type.iommu_ops != &arm_smmu_ops) {
ret = bus_set_iommu(&platform_bus_type, &arm_smmu_ops);
if (ret)
return ret;
}
return 0;
} }
static int arm_smmu_device_remove(struct platform_device *pdev) static int arm_smmu_device_remove(struct platform_device *pdev)
......
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