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authorJoerg Roedel <joerg.roedel@amd.com>2011-11-10 14:41:57 +0100
committerJoerg Roedel <joerg.roedel@amd.com>2011-12-12 14:54:30 +0100
commit62f71abbc64d686064a4caa10a3249c26776995e (patch)
treedd902320a0048af1a46212698f342552b77d943f /drivers/iommu
parentee6c28684585a64fd79c5a56e849af58ebdc5948 (diff)
iommu/amd: Get the maximum number of PASIDs supported
Read the number of PASIDs supported by each IOMMU in the system and take the smallest number as the maximum value supported by the IOMMU driver. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Diffstat (limited to 'drivers/iommu')
-rw-r--r--drivers/iommu/amd_iommu_init.c13
-rw-r--r--drivers/iommu/amd_iommu_types.h6
2 files changed, 19 insertions, 0 deletions
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 17e0f77c7da..fb4afd6d357 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -141,6 +141,8 @@ int amd_iommus_present;
bool amd_iommu_np_cache __read_mostly;
bool amd_iommu_iotlb_sup __read_mostly = true;
+u32 amd_iommu_max_pasids __read_mostly = ~0;
+
/*
* The ACPI table parsing functions set this variable on an error
*/
@@ -699,6 +701,17 @@ static void __init init_iommu_from_pci(struct amd_iommu *iommu)
iommu->features = ((u64)high << 32) | low;
+ if (iommu_feature(iommu, FEATURE_GT)) {
+ u32 pasids;
+ u64 shift;
+
+ shift = iommu->features & FEATURE_PASID_MASK;
+ shift >>= FEATURE_PASID_SHIFT;
+ pasids = (1 << shift);
+
+ amd_iommu_max_pasids = min(amd_iommu_max_pasids, pasids);
+ }
+
if (!is_rd890_iommu(iommu->dev))
return;
diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index f8dd9ae693d..0d984ca925b 100644
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -87,6 +87,9 @@
#define FEATURE_HE (1ULL<<8)
#define FEATURE_PC (1ULL<<9)
+#define FEATURE_PASID_SHIFT 32
+#define FEATURE_PASID_MASK (0x1fULL << FEATURE_PASID_SHIFT)
+
/* MMIO status bits */
#define MMIO_STATUS_COM_WAIT_INT_MASK 0x04
@@ -549,6 +552,9 @@ extern unsigned long *amd_iommu_pd_alloc_bitmap;
*/
extern bool amd_iommu_unmap_flush;
+/* Smallest number of PASIDs supported by any IOMMU in the system */
+extern u32 amd_iommu_max_pasids;
+
/* takes bus and device/function and returns the device id
* FIXME: should that be in generic PCI code? */
static inline u16 calc_devid(u8 bus, u8 devfn)