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MMIO and Capability registers - Add support to dump MMIO and Capability registers per IOMMU. Example: a. Write MMIO register offset to dump it $ echo 0x18 > /sys/kernel/debug/iommu/amd/iommu00/mmio $ cat /sys/kernel/debug/iommu/amd/iommu00/mmio Output: $ 0x0003f48d b. Write capability register offset to dump it $ echo 0x10 > /sys/kernel/debug/iommu/amd/iommu00/capability $ cat /sys/kernel/debug/iommu/amd/iommu00/capability Output: $ 0x00203040 2. Command buffer - Add support to dump per IOMMU command buffer. Example: a. cat /sys/kernel/debug/iommu/amd/iommu00/cmdbuf Output: CMD Buffer Head Offset:339 Tail Offset:339 0: 00835001100000010000990000000000 1: 0000000030000005fffff0037fffffff 2: 00835001100000010000990100000000 3: 0000000030000005fffff0037fffffff 4: 00835001100000010000990200000000 ................................... ................................... ................................... 3. Device table - Add support to dump device table per IOMMU. Example: a. Write device id to dump device table entry for that device $ echo 0000:01:00.0 > /sys/kernel/debug/iommu/amd/devid $ cat /sys/kernel/debug/iommu/amd/devid Output: 0000:01:00.0 Dump the device table entry for the input given $ cat /sys/kernel/debug/iommu/amd/devtbl Output: DeviceId QWORD[3] QWORD[2] QWORD[1] QWORD[0] iommu 0000:01:00.0 0000000000000000 20000001373b8013 0000000000000038 6000000114d7b603 iommu3 b. Write device id to dump device table entry for that device $ echo 01:00.0 > /sys/kernel/debug/iommu/amd/devid $ cat /sys/kernel/debug/iommu/amd/devid Output: 0000:01:00.0 Dump the device table entry for the input given $ cat /sys/kernel/debug/iommu/amd/devtbl Output: DeviceId QWORD[3] QWORD[2] QWORD[1] QWORD[0] iommu 0000:01:00.0 0000000000000000 20000001373b8013 0000000000000038 6000000114d7b603 iommu3 4. Interrupt remapping table - Add support to dump IRT table valid entries in "iommu_irqtbl" file. This supports user input to dump IRT entry for a specific pci device. Example: a. Write device id to dump device table entry for that device $ echo 0000:01:00.0 > /sys/kernel/debug/iommu/amd/devid $ cat /sys/kernel/debug/iommu/amd/devid Output: 0000:01:00.0 Dump the device table entry for the input given $ cat /sys/kernel/debug/iommu/amd/irtbl Output: DeviceId 0000:01:00.0 IRT[0000] 00000000000000200000000000000241 IRT[0001] 00000000000000200000000000000841 IRT[0002] 00000000000000200000000000002041 IRT[0003] 00000000000000200000000000008041 IRT[0004] 00000000000000200000000000020041 .......................................... .......................................... .......................................... b. Write device id to dump device table entry for that device $ echo 01:00.0 > /sys/kernel/debug/iommu/amd/devid $ cat /sys/kernel/debug/iommu/amd/devid Output: 0000:01:00.0 Dump the device table entry for the input given $ cat /sys/kernel/debug/iommu/amd/irttbl Output: Device 0000:01:00.0 IRT[0000] 00000000000000200000000000000241 IRT[0001] 00000000000000200000000000000841 IRT[0002] 00000000000000200000000000002041 IRT[0003] 00000000000000200000000000008041 IRT[0004] 00000000000000200000000000020041 .......................................... .......................................... .......................................... Open question:[Suggestion from Bjorn Helgaas] Instead of using device-id input with "/sys/kernel/debug/iommu/amd/devid", can we have something like other drivers have "/sys/kernel/debug/iommu/amd/<bdf>/". Each "/sys/kernel/debug/iommu/amd/<bdf>/" will have "devtbl" and "irqtbl" files for device table and interrupt remapping table dump file. Changes since v2: -> Patch 2/8 and 3/8: Use single file mmio and capability for input and output registers offset and registers dump respctively. -> Patch 8/8: Correct path for files "irqtbl" and "devtbl" in Documentation Changes since v1: -> Patch 2/8 and 3/8: Use kstrtou32_from_user() instead of memdup_user_nul() --> kstrtou32() -> Patch 4/8: Dump command buffer head and tail offset instead of head and tail pointer registers. -> Patch 8/8: Fix bot reported warning on v1 upstream. Dheeraj Kumar Srivastava (8): iommu/amd: Refactor AMD IOMMU debugfs initial setup iommu/amd: Add debugfs support to dump IOMMU MMIO registers iommu/amd: Add debugfs support to dump IOMMU Capability registers iommu/amd: Add debugfs support to dump IOMMU command buffer iommu/amd: Add support for device id user input iommu/amd: Add debugfs support to dump device table iommu/amd: Add debugfs support to dump IRT Table iommu/amd: Add documentation for AMD IOMMU debugfs support Documentation/ABI/testing/debugfs-amd-iommu | 114 +++++++ drivers/iommu/amd/amd_iommu.h | 4 +- drivers/iommu/amd/amd_iommu_types.h | 7 + drivers/iommu/amd/debugfs.c | 350 +++++++++++++++++++- drivers/iommu/amd/init.c | 5 +- drivers/iommu/amd/iommu.c | 7 - 6 files changed, 466 insertions(+), 21 deletions(-) create mode 100644 Documentation/ABI/testing/debugfs-amd-iommu -- 2.25.1 </pre></td><td width="32" rowspan="2" class="c" valign="top"><img src="/images/icornerr.gif" width="32" height="32" alt="\" /></td></tr><tr><td align="right" valign="bottom"> 聽 </td></tr><tr><td align="right" valign="bottom">聽</td><td class="c" valign="bottom" style="padding-bottom: 0px"><img src="/images/bcornerl.gif" width="32" height="32" alt="\" /></td><td class="c">聽</td><td class="c" valign="bottom" style="padding-bottom: 0px"><img src="/images/bcornerr.gif" width="32" height="32" alt="/" /></td></tr><tr><td align="right" valign="top" colspan="2"> 聽 </td><td class="lm">Last update: 2025-02-06 07:01 聽聽 [W:0.266 / U:9.719 seconds] 漏2003-2020 <a href="http://blog.jasper.es/">Jasper Spaans</a>|hosted at <a href="https://www.digitalocean.com/?refcode=9a8e99d24cf9">Digital Ocean</a> and my Meterkast|<a href="http://blog.jasper.es/categories.html#lkml-ref">Read the blog</a></td><td>聽</td></tr></table><script language="javascript" src="/js/styleswitcher.js" type="text/javascript"></script></body></html>