[PATCH v5 03/17] iommu/arm-smmu-v3: Move arm_smmu_rmr_install_bypass_ste()

Jason Gunthorpe jgg at nvidia.com
Tue Feb 6 07:12:40 PST 2024


Logically arm_smmu_init_strtab() is the function that allocates and
populates the stream table with the initial value of the STEs. After this
function returns the stream table should be fully ready.

arm_smmu_rmr_install_bypass_ste() adjusts the initial stream table to force
any SIDs that the FW says have IOMMU_RESV_DIRECT to use bypass. This
ensures there is no disruption to the identity mapping during boot.

Put arm_smmu_rmr_install_bypass_ste() into arm_smmu_init_strtab(), it
already executes immediately after arm_smmu_init_strtab().

No functional change intended.

Tested-by: Shameer Kolothum <shameerali.kolothum.thodi at huawei.com>
Tested-by: Nicolin Chen <nicolinc at nvidia.com>
Tested-by: Moritz Fischer <moritzf at google.com>
Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 6123e5ad95822c..2ab36dcf7c61f5 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -101,6 +101,8 @@ static struct arm_smmu_option_prop arm_smmu_options[] = {
 	{ 0, NULL},
 };
 
+static void arm_smmu_rmr_install_bypass_ste(struct arm_smmu_device *smmu);
+
 static void parse_driver_options(struct arm_smmu_device *smmu)
 {
 	int i = 0;
@@ -3256,6 +3258,7 @@ static int arm_smmu_init_strtab_linear(struct arm_smmu_device *smmu)
 	cfg->strtab_base_cfg = reg;
 
 	arm_smmu_init_bypass_stes(strtab, cfg->num_l1_ents);
+
 	return 0;
 }
 
@@ -3279,6 +3282,8 @@ static int arm_smmu_init_strtab(struct arm_smmu_device *smmu)
 
 	ida_init(&smmu->vmid_map);
 
+	/* Check for RMRs and install bypass STEs if any */
+	arm_smmu_rmr_install_bypass_ste(smmu);
 	return 0;
 }
 
@@ -4073,9 +4078,6 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
 	/* Record our private device structure */
 	platform_set_drvdata(pdev, smmu);
 
-	/* Check for RMRs and install bypass STEs if any */
-	arm_smmu_rmr_install_bypass_ste(smmu);
-
 	/* Reset the device */
 	ret = arm_smmu_device_reset(smmu, bypass);
 	if (ret)
-- 
2.43.0




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