iommu/amd: Enable GT mode when supported by IOMMU
This feature needs to be enabled before IOMMUv2 DTEs can be
set up.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 60716ce..2c25ae3 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -623,6 +623,14 @@
free_pages((unsigned long)iommu->ppr_log, get_order(PPR_LOG_SIZE));
}
+static void iommu_enable_gt(struct amd_iommu *iommu)
+{
+ if (!iommu_feature(iommu, FEATURE_GT))
+ return;
+
+ iommu_feature_enable(iommu, CONTROL_GT_EN);
+}
+
/* sets a specific bit in the device table entry. */
static void set_dev_entry_bit(u16 devid, u8 bit)
{
@@ -1338,6 +1346,7 @@
iommu_enable_command_buffer(iommu);
iommu_enable_event_buffer(iommu);
iommu_enable_ppr_log(iommu);
+ iommu_enable_gt(iommu);
iommu_set_exclusion_range(iommu);
iommu_init_msi(iommu);
iommu_enable(iommu);