[PATCH v2 26/26] iommu/amd: Introduce logic to check and enable vIOMMU feature

[Suravee Suthikulpanit]

Also switch to enable vIOMMU by default.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
---
 drivers/iommu/amd/amd_iommu.h       |  1 +
 drivers/iommu/amd/amd_iommu_types.h |  3 +++
 drivers/iommu/amd/init.c            | 12 +++++++++++-
 drivers/iommu/amd/viommu.c          | 24 +++++++++++++++++++++++-
 4 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/amd/amd_iommu.h b/drivers/iommu/amd/amd_iommu.h
index cf2b051948a3..e505c5420255 100644
--- a/drivers/iommu/amd/amd_iommu.h
+++ b/drivers/iommu/amd/amd_iommu.h
@@ -27,6 +27,7 @@ void amd_iommu_restart_ga_log(struct amd_iommu *iommu);
 void amd_iommu_restart_ppr_log(struct amd_iommu *iommu);
 void amd_iommu_set_rlookup_table(struct amd_iommu *iommu, u16 devid);
 void iommu_feature_enable(struct amd_iommu *iommu, u8 bit);
+bool iommu_feature_enable_and_check(struct amd_iommu *iommu, u8 bit);
 void *__init iommu_alloc_4k_pages(struct amd_iommu *iommu,
 				  gfp_t gfp, size_t size);
 u8 __iomem * __init iommu_map_mmio_space(u64 address, u64 end);
diff --git a/drivers/iommu/amd/amd_iommu_types.h b/drivers/iommu/amd/amd_iommu_types.h
index 44a185bfa39e..7ff714ce79b8 100644
--- a/drivers/iommu/amd/amd_iommu_types.h
+++ b/drivers/iommu/amd/amd_iommu_types.h
@@ -201,9 +201,12 @@
 #define CONTROL_EPH_EN		45
 #define CONTROL_PPR_AUTO_RSP_AON 48
 #define CONTROL_XT_EN		50
+#define CONTROL_VCMD_EN         52
+#define CONTROL_VIOMMU_EN       53
 #define CONTROL_INTCAPXT_EN	51
 #define CONTROL_GCR3TRPMODE	58
 #define CONTROL_IRTCACHEDIS	59
+#define CONTROL_GSTBUFFERTRPMODE	60
 #define CONTROL_SNPAVIC_EN	61
 
 #define CTRL_INV_TO_MASK	7
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index 622bc0337eda..a66a5089bf91 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -198,7 +198,7 @@ bool amdr_ivrs_remap_support __read_mostly;
 bool amd_iommu_force_isolation __read_mostly;
 
 /* VIOMMU enabling flag */
-bool amd_iommu_viommu;
+bool amd_iommu_viommu = true;
 
 unsigned long amd_iommu_pgsize_bitmap __ro_after_init = AMD_IOMMU_PGSIZES;
 
@@ -417,6 +417,16 @@ void iommu_feature_enable(struct amd_iommu *iommu, u8 bit)
 	iommu_feature_set(iommu, 1ULL, 1ULL, bit);
 }
 
+bool iommu_feature_enable_and_check(struct amd_iommu *iommu, u8 bit)
+{
+	u64 ctrl;
+
+	iommu_feature_enable(iommu, bit);
+
+	ctrl = readq(iommu->mmio_base +  MMIO_CONTROL_OFFSET);
+	return (ctrl & (1ULL << bit));
+}
+
 static void iommu_feature_disable(struct amd_iommu *iommu, u8 bit)
 {
 	iommu_feature_set(iommu, 0ULL, 1ULL, bit);
diff --git a/drivers/iommu/amd/viommu.c b/drivers/iommu/amd/viommu.c
index d2c883e314f8..4dcd781bc35a 100644
--- a/drivers/iommu/amd/viommu.c
+++ b/drivers/iommu/amd/viommu.c
@@ -45,6 +45,18 @@
 
 LIST_HEAD(viommu_devid_map);
 
+static int viommu_enable(struct amd_iommu *iommu)
+{
+	/* The GstBufferTRPMode feature is checked by set and test */
+	if (!iommu_feature_enable_and_check(iommu, CONTROL_GSTBUFFERTRPMODE))
+		return -EINVAL;
+
+	iommu_feature_enable(iommu, CONTROL_VCMD_EN);
+	iommu_feature_enable(iommu, CONTROL_VIOMMU_EN);
+
+	return 0;
+}
+
 static int viommu_init_pci_vsc(struct amd_iommu *iommu)
 {
 	iommu->vsc_offset = pci_find_capability(iommu->dev, PCI_CAP_ID_VNDR);
@@ -308,11 +320,21 @@ int __init amd_viommu_init(struct amd_iommu *iommu)
 
 	ret = viommu_private_space_init(iommu);
 	if (ret)
-		return ret;
+		goto err_unmap_vf;
 
 	set_iommu_dte(iommu);
 
+	ret = viommu_enable(iommu);
+	if (ret)
+		goto err_private_space;
+
 	return 0;
+
+err_private_space:
+	viommu_private_space_uninit(iommu);
+err_unmap_vf:
+	amd_viommu_uninit(iommu);
+	return ret;
 }
 
 static int __maybe_unused alloc_private_vm_region(struct amd_iommu *iommu, u64 **entry,
-- 
2.34.1