On systems booting with ACPI that enable the ARM SMMU components in the kernel config options, the ARM SMMU v3 init function (ie arm_smmu_init(), that registers the driver and sets-up bus iommu operations) does not run only because the device tree interface (of_find_matching_node()) fails to find the respective device tree nodes for ARM SMMU devices. This works as long as there are no ARM SMMU devices to be probed with ACPI. If ARM SMMU v3 components are part of the IORT tables, for them to be instantiated and probed the function registering the ARM SMMU v3 driver must be able to register the driver and initialize the bus IOMMU operations accordingly. This patch changes the logic in arm-smmu-v3 init call to allow for it to be probed in ACPI systems. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> Acked-by: Will Deacon <will.deacon@xxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Cc: Robin Murphy <robin.murphy@xxxxxxx> Cc: Joerg Roedel <joro@xxxxxxxxxx> --- drivers/iommu/arm-smmu-v3.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index 91a7600..75b78f9 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -2689,11 +2689,16 @@ static int __init arm_smmu_init(void) if (registered) return 0; - np = of_find_matching_node(NULL, arm_smmu_of_match); - if (!np) - return 0; + if (acpi_disabled) { + np = of_find_matching_node(NULL, arm_smmu_of_match); + if (!np) + return 0; - of_node_put(np); + of_node_put(np); + } else { + if (!iort_node_match(ACPI_IORT_NODE_SMMU_V3)) + return 0; + } ret = platform_driver_register(&arm_smmu_driver); if (ret) -- 2.6.4 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html