[PATCH v2 3/3] iommu/arm-smmu-qcom: hook up qcom_smmu_impl for ACPI boot

Shawn Guo shawn.guo at linaro.org
Fri Apr 2 04:56:02 BST 2021


The hookup with qcom_smmu_impl is required to do ACPI boot on SC8180X
based devices like Lenovo Flex 5G laptop and Microsoft Surface Pro X.
Check IORT SMMU model identifier and create qcom_smmu_impl accordingly.

(np == NULL) is used to check ACPI boot, because fwnode of SMMU device
is a static allocation and thus helpers like has_acpi_companion() don't
work here.

Signed-off-by: Shawn Guo <shawn.guo at linaro.org>
---
 drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
index 82c7edc6e025..7ced0f93bc99 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
@@ -3,6 +3,7 @@
  * Copyright (c) 2019, The Linux Foundation. All rights reserved.
  */
 
+#include <linux/acpi_iort.h>
 #include <linux/adreno-smmu-priv.h>
 #include <linux/of_device.h>
 #include <linux/qcom_scm.h>
@@ -340,6 +341,14 @@ struct arm_smmu_device *qcom_smmu_impl_init(struct arm_smmu_device *smmu)
 {
 	const struct device_node *np = smmu->dev->of_node;
 
+	if (np == NULL) {
+		/* ACPI boot */
+		struct iort_smmu_pdata *pdata = dev_get_platdata(smmu->dev);
+
+		if (pdata && pdata->model == IORT_SMMU_QCOM)
+			return qcom_smmu_create(smmu, &qcom_smmu_impl);
+	}
+
 	if (of_match_node(qcom_smmu_impl_of_match, np))
 		return qcom_smmu_create(smmu, &qcom_smmu_impl);
 
-- 
2.17.1




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