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Diffstat (limited to 'Documentation/ABI/testing/debugfs-intel-iommu')
| -rw-r--r-- | Documentation/ABI/testing/debugfs-intel-iommu | 276 |
1 files changed, 276 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/debugfs-intel-iommu b/Documentation/ABI/testing/debugfs-intel-iommu new file mode 100644 index 0000000000..2ab8464504 --- /dev/null +++ b/Documentation/ABI/testing/debugfs-intel-iommu @@ -0,0 +1,276 @@ +What: /sys/kernel/debug/iommu/intel/iommu_regset +Date: December 2023 +Contact: Jingqi Liu <Jingqi.liu@intel.com> +Description: + This file dumps all the register contents for each IOMMU device. + + Example in Kabylake: + + :: + + $ sudo cat /sys/kernel/debug/iommu/intel/iommu_regset + + IOMMU: dmar0 Register Base Address: 26be37000 + + Name Offset Contents + VER 0x00 0x0000000000000010 + GCMD 0x18 0x0000000000000000 + GSTS 0x1c 0x00000000c7000000 + FSTS 0x34 0x0000000000000000 + FECTL 0x38 0x0000000000000000 + + [...] + + IOMMU: dmar1 Register Base Address: fed90000 + + Name Offset Contents + VER 0x00 0x0000000000000010 + GCMD 0x18 0x0000000000000000 + GSTS 0x1c 0x00000000c7000000 + FSTS 0x34 0x0000000000000000 + FECTL 0x38 0x0000000000000000 + + [...] + + IOMMU: dmar2 Register Base Address: fed91000 + + Name Offset Contents + VER 0x00 0x0000000000000010 + GCMD 0x18 0x0000000000000000 + GSTS 0x1c 0x00000000c7000000 + FSTS 0x34 0x0000000000000000 + FECTL 0x38 0x0000000000000000 + + [...] + +What: /sys/kernel/debug/iommu/intel/ir_translation_struct +Date: December 2023 +Contact: Jingqi Liu <Jingqi.liu@intel.com> +Description: + This file dumps the table entries for Interrupt + remapping and Interrupt posting. + + Example in Kabylake: + + :: + + $ sudo cat /sys/kernel/debug/iommu/intel/ir_translation_struct + + Remapped Interrupt supported on IOMMU: dmar0 + IR table address:100900000 + + Entry SrcID DstID Vct IRTE_high IRTE_low + 0 00:0a.0 00000080 24 0000000000040050 000000800024000d + 1 00:0a.0 00000001 ef 0000000000040050 0000000100ef000d + + Remapped Interrupt supported on IOMMU: dmar1 + IR table address:100300000 + Entry SrcID DstID Vct IRTE_high IRTE_low + 0 00:02.0 00000002 26 0000000000040010 000000020026000d + + [...] + + **** + + Posted Interrupt supported on IOMMU: dmar0 + IR table address:100900000 + Entry SrcID PDA_high PDA_low Vct IRTE_high IRTE_low + +What: /sys/kernel/debug/iommu/intel/dmar_translation_struct +Date: December 2023 +Contact: Jingqi Liu <Jingqi.liu@intel.com> +Description: + This file dumps Intel IOMMU DMA remapping tables, such + as root table, context table, PASID directory and PASID + table entries in debugfs. For legacy mode, it doesn't + support PASID, and hence PASID field is defaulted to + '-1' and other PASID related fields are invalid. + + Example in Kabylake: + + :: + + $ sudo cat /sys/kernel/debug/iommu/intel/dmar_translation_struct + + IOMMU dmar1: Root Table Address: 0x103027000 + B.D.F Root_entry + 00:02.0 0x0000000000000000:0x000000010303e001 + + Context_entry + 0x0000000000000102:0x000000010303f005 + + PASID PASID_table_entry + -1 0x0000000000000000:0x0000000000000000:0x0000000000000000 + + IOMMU dmar0: Root Table Address: 0x103028000 + B.D.F Root_entry + 00:0a.0 0x0000000000000000:0x00000001038a7001 + + Context_entry + 0x0000000000000000:0x0000000103220e7d + + PASID PASID_table_entry + 0 0x0000000000000000:0x0000000000800002:0x00000001038a5089 + + [...] + +What: /sys/kernel/debug/iommu/intel/invalidation_queue +Date: December 2023 +Contact: Jingqi Liu <Jingqi.liu@intel.com> +Description: + This file exports invalidation queue internals of each + IOMMU device. + + Example in Kabylake: + + :: + + $ sudo cat /sys/kernel/debug/iommu/intel/invalidation_queue + + Invalidation queue on IOMMU: dmar0 + Base: 0x10022e000 Head: 20 Tail: 20 + Index qw0 qw1 qw2 + 0 0000000000000014 0000000000000000 0000000000000000 + 1 0000000200000025 0000000100059c04 0000000000000000 + 2 0000000000000014 0000000000000000 0000000000000000 + + qw3 status + 0000000000000000 0000000000000000 + 0000000000000000 0000000000000000 + 0000000000000000 0000000000000000 + + [...] + + Invalidation queue on IOMMU: dmar1 + Base: 0x10026e000 Head: 32 Tail: 32 + Index qw0 qw1 status + 0 0000000000000004 0000000000000000 0000000000000000 + 1 0000000200000025 0000000100059804 0000000000000000 + 2 0000000000000011 0000000000000000 0000000000000000 + + [...] + +What: /sys/kernel/debug/iommu/intel/dmar_perf_latency +Date: December 2023 +Contact: Jingqi Liu <Jingqi.liu@intel.com> +Description: + This file is used to control and show counts of + execution time ranges for various types per DMAR. + + Firstly, write a value to + /sys/kernel/debug/iommu/intel/dmar_perf_latency + to enable sampling. + + The possible values are as follows: + + * 0 - disable sampling all latency data + + * 1 - enable sampling IOTLB invalidation latency data + + * 2 - enable sampling devTLB invalidation latency data + + * 3 - enable sampling intr entry cache invalidation latency data + + Next, read /sys/kernel/debug/iommu/intel/dmar_perf_latency gives + a snapshot of sampling result of all enabled monitors. + + Examples in Kabylake: + + :: + + 1) Disable sampling all latency data: + + $ sudo echo 0 > /sys/kernel/debug/iommu/intel/dmar_perf_latency + + 2) Enable sampling IOTLB invalidation latency data + + $ sudo echo 1 > /sys/kernel/debug/iommu/intel/dmar_perf_latency + + $ sudo cat /sys/kernel/debug/iommu/intel/dmar_perf_latency + + IOMMU: dmar0 Register Base Address: 26be37000 + <0.1us 0.1us-1us 1us-10us 10us-100us 100us-1ms + inv_iotlb 0 0 0 0 0 + + 1ms-10ms >=10ms min(us) max(us) average(us) + inv_iotlb 0 0 0 0 0 + + [...] + + IOMMU: dmar2 Register Base Address: fed91000 + <0.1us 0.1us-1us 1us-10us 10us-100us 100us-1ms + inv_iotlb 0 0 18 0 0 + + 1ms-10ms >=10ms min(us) max(us) average(us) + inv_iotlb 0 0 2 2 2 + + 3) Enable sampling devTLB invalidation latency data + + $ sudo echo 2 > /sys/kernel/debug/iommu/intel/dmar_perf_latency + + $ sudo cat /sys/kernel/debug/iommu/intel/dmar_perf_latency + + IOMMU: dmar0 Register Base Address: 26be37000 + <0.1us 0.1us-1us 1us-10us 10us-100us 100us-1ms + inv_devtlb 0 0 0 0 0 + + >=10ms min(us) max(us) average(us) + inv_devtlb 0 0 0 0 + + [...] + +What: /sys/kernel/debug/iommu/intel/<bdf>/domain_translation_struct +Date: December 2023 +Contact: Jingqi Liu <Jingqi.liu@intel.com> +Description: + This file dumps a specified page table of Intel IOMMU + in legacy mode or scalable mode. + + For a device that only supports legacy mode, dump its + page table by the debugfs file in the debugfs device + directory. e.g. + /sys/kernel/debug/iommu/intel/0000:00:02.0/domain_translation_struct. + + For a device that supports scalable mode, dump the + page table of specified pasid by the debugfs file in + the debugfs pasid directory. e.g. + /sys/kernel/debug/iommu/intel/0000:00:02.0/1/domain_translation_struct. + + Examples in Kabylake: + + :: + + 1) Dump the page table of device "0000:00:02.0" that only supports legacy mode. + + $ sudo cat /sys/kernel/debug/iommu/intel/0000:00:02.0/domain_translation_struct + + Device 0000:00:02.0 @0x1017f8000 + IOVA_PFN PML5E PML4E + 0x000000008d800 | 0x0000000000000000 0x00000001017f9003 + 0x000000008d801 | 0x0000000000000000 0x00000001017f9003 + 0x000000008d802 | 0x0000000000000000 0x00000001017f9003 + + PDPE PDE PTE + 0x00000001017fa003 0x00000001017fb003 0x000000008d800003 + 0x00000001017fa003 0x00000001017fb003 0x000000008d801003 + 0x00000001017fa003 0x00000001017fb003 0x000000008d802003 + + [...] + + 2) Dump the page table of device "0000:00:0a.0" with PASID "1" that + supports scalable mode. + + $ sudo cat /sys/kernel/debug/iommu/intel/0000:00:0a.0/1/domain_translation_struct + + Device 0000:00:0a.0 with pasid 1 @0x10c112000 + IOVA_PFN PML5E PML4E + 0x0000000000000 | 0x0000000000000000 0x000000010df93003 + 0x0000000000001 | 0x0000000000000000 0x000000010df93003 + 0x0000000000002 | 0x0000000000000000 0x000000010df93003 + + PDPE PDE PTE + 0x0000000106ae6003 0x0000000104b38003 0x0000000147c00803 + 0x0000000106ae6003 0x0000000104b38003 0x0000000147c01803 + 0x0000000106ae6003 0x0000000104b38003 0x0000000147c02803 + + [...] |