From: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> The IOMMU probe deferral implementation requires a mechanism to detect if drivers for SMMU components are built-in in the kernel to detect whether IOMMU configuration for a given device should be deferred (ie SMMU drivers present but still not probed) or not (drivers not present). Add a simple function to IORT to detect if SMMU drivers for SMMU components managed by IORT are built-in in the kernel. Tested-by: Hanjun Guo <hanjun.guo@xxxxxxxxxx> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx> Cc: Sricharan R <sricharan@xxxxxxxxxxxxxx> --- drivers/acpi/arm64/iort.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index 4a5bb96..3dd9ec3 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -523,6 +523,19 @@ static int arm_smmu_iort_xlate(struct device *dev, u32 streamid, return ret; } +static inline bool iort_iommu_driver_enabled(u8 type) +{ + switch (type) { + case ACPI_IORT_NODE_SMMU_V3: + return IS_BUILTIN(CONFIG_ARM_SMMU_V3); + case ACPI_IORT_NODE_SMMU: + return IS_BUILTIN(CONFIG_ARM_SMMU); + default: + pr_warn("IORT node type %u does not describe an SMMU\n", type); + return false; + } +} + static const struct iommu_ops *iort_iommu_xlate(struct device *dev, struct acpi_iort_node *node, u32 streamid) -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation