diff options
| author | Sairaj Kodilkar <sarunkod@amd.com> | 2025-03-17 11:20:20 +0530 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2025-05-02 08:38:09 +0200 |
| commit | 94a9921e2c25eedcf95b00cedbd065579406655a (patch) | |
| tree | eb0cbf36fbe367c8557f388ea5bffecd0d23e8f0 | |
| parent | 94c721ea03c7078163f41dbaa101ac721ddac329 (diff) | |
iommu/amd: Add support for HTRangeIgnore feature
AMD IOMMU reserves the address range 0xfd00000000-0xffffffffff for
the hypertransport protocol (HT) and has special meaning. Hence devices
cannot use this address range for the DMA. However on some AMD platforms
this HT range is shifted to the very top of the address space and new
feature bit `HTRangeIgnore` is introduced. When this feature bit is on,
IOMMU treats the GPA access to the legacy HT range as regular GPA access.
Signed-off-by: Sairaj Kodilkar <sarunkod@amd.com>
Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>
Link: https://lore.kernel.org/r/20250317055020.25214-1-sarunkod@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
| -rw-r--r-- | drivers/iommu/amd/amd_iommu.h | 2 | ||||
| -rw-r--r-- | drivers/iommu/amd/amd_iommu_types.h | 1 | ||||
| -rw-r--r-- | drivers/iommu/amd/init.c | 5 | ||||
| -rw-r--r-- | drivers/iommu/amd/iommu.c | 3 |
4 files changed, 11 insertions, 0 deletions
diff --git a/drivers/iommu/amd/amd_iommu.h b/drivers/iommu/amd/amd_iommu.h index 220c598b7e14..29a8864381c3 100644 --- a/drivers/iommu/amd/amd_iommu.h +++ b/drivers/iommu/amd/amd_iommu.h @@ -147,6 +147,8 @@ static inline int get_pci_sbdf_id(struct pci_dev *pdev) return PCI_SEG_DEVID_TO_SBDF(seg, devid); } +bool amd_iommu_ht_range_ignore(void); + /* * This must be called after device probe completes. During probe * use rlookup_amd_iommu() get the iommu. diff --git a/drivers/iommu/amd/amd_iommu_types.h b/drivers/iommu/amd/amd_iommu_types.h index 5089b58e528a..11dd152cfa95 100644 --- a/drivers/iommu/amd/amd_iommu_types.h +++ b/drivers/iommu/amd/amd_iommu_types.h @@ -111,6 +111,7 @@ #define FEATURE_SNPAVICSUP GENMASK_ULL(7, 5) #define FEATURE_SNPAVICSUP_GAM(x) \ (FIELD_GET(FEATURE_SNPAVICSUP, x) == 0x1) +#define FEATURE_HT_RANGE_IGNORE BIT_ULL(11) #define FEATURE_NUM_INT_REMAP_SUP GENMASK_ULL(9, 8) #define FEATURE_NUM_INT_REMAP_SUP_2K(x) \ diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c index dd9e26b7b718..acf8941e1ed3 100644 --- a/drivers/iommu/amd/init.c +++ b/drivers/iommu/amd/init.c @@ -256,6 +256,11 @@ int amd_iommu_get_num_iommus(void) return amd_iommus_present; } +bool amd_iommu_ht_range_ignore(void) +{ + return check_feature2(FEATURE_HT_RANGE_IGNORE); +} + /* * Iterate through all the IOMMUs to get common EFR * masks among all IOMMUs and warn if found inconsistency. diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c index 15e334264881..95520bcf6c0e 100644 --- a/drivers/iommu/amd/iommu.c +++ b/drivers/iommu/amd/iommu.c @@ -2916,6 +2916,9 @@ static void amd_iommu_get_resv_regions(struct device *dev, return; list_add_tail(®ion->list, head); + if (amd_iommu_ht_range_ignore()) + return; + region = iommu_alloc_resv_region(HT_RANGE_START, HT_RANGE_END - HT_RANGE_START + 1, 0, IOMMU_RESV_RESERVED, GFP_KERNEL); |