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{
    "id": 2215662,
    "url": "http://patchwork.ozlabs.org/api/covers/2215662/?format=api",
    "web_url": "http://patchwork.ozlabs.org/project/linux-pci/cover/1774403912-210670-1-git-send-email-shawn.lin@rock-chips.com/",
    "project": {
        "id": 28,
        "url": "http://patchwork.ozlabs.org/api/projects/28/?format=api",
        "name": "Linux PCI development",
        "link_name": "linux-pci",
        "list_id": "linux-pci.vger.kernel.org",
        "list_email": "linux-pci@vger.kernel.org",
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    "msgid": "<1774403912-210670-1-git-send-email-shawn.lin@rock-chips.com>",
    "list_archive_url": null,
    "date": "2026-03-25T01:58:29",
    "name": "[v5,0/3] PCI Controller event and LTSSM tracepoint support",
    "submitter": {
        "id": 66993,
        "url": "http://patchwork.ozlabs.org/api/people/66993/?format=api",
        "name": "Shawn Lin",
        "email": "shawn.lin@rock-chips.com"
    },
    "mbox": "http://patchwork.ozlabs.org/project/linux-pci/cover/1774403912-210670-1-git-send-email-shawn.lin@rock-chips.com/mbox/",
    "series": [
        {
            "id": 497375,
            "url": "http://patchwork.ozlabs.org/api/series/497375/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/linux-pci/list/?series=497375",
            "date": "2026-03-25T01:58:29",
            "name": "PCI Controller event and LTSSM tracepoint support",
            "version": 5,
            "mbox": "http://patchwork.ozlabs.org/series/497375/mbox/"
        }
    ],
    "comments": "http://patchwork.ozlabs.org/api/covers/2215662/comments/",
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        "From": "Shawn Lin <shawn.lin@rock-chips.com>",
        "To": "Manivannan Sadhasivam <mani@kernel.org>,\n\tBjorn Helgaas <bhelgaas@google.com>",
        "Cc": "linux-rockchip@lists.infradead.org,\n\tlinux-pci@vger.kernel.org,\n\tlinux-trace-kernel@vger.kernel.org,\n\tlinux-doc@vger.kernel.org,\n\tSteven Rostedt <rostedt@goodmis.org>,\n\tShawn Lin <shawn.lin@rock-chips.com>",
        "Subject": "[PATCH v5 0/3] PCI Controller event and LTSSM tracepoint support",
        "Date": "Wed, 25 Mar 2026 09:58:29 +0800",
        "Message-Id": "<1774403912-210670-1-git-send-email-shawn.lin@rock-chips.com>",
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        "X-Mailing-List": "linux-pci@vger.kernel.org",
        "List-Id": "<linux-pci.vger.kernel.org>",
        "List-Subscribe": "<mailto:linux-pci+subscribe@vger.kernel.org>",
        "List-Unsubscribe": "<mailto:linux-pci+unsubscribe@vger.kernel.org>"
    },
    "content": "This patch-set adds new pci controller event and LTSSM tracepoint used by host drivers\nwhich provide LTSSM trace functionality. The first user is pcie-dw-rockchip with a 256\nBytes FIFO for recording LTSSM transition.\n\nTesting\n=========\n\nThis series was tested on RK3588/RK3588s EVB1 with NVMe SSD connected to PCIe3 and PCIe2\nroot ports.\n\necho 1 > /sys/kernel/debug/tracing/events/pci_controller/pcie_ltssm_state_transition/enable\ncat /sys/kernel/debug/tracing/trace_pipe\n\n # tracer: nop\n #\n # entries-in-buffer/entries-written: 64/64   #P:8\n #\n #                                _-----=> irqs-off/BH-disabled\n #                               / _----=> need-resched\n #                              | / _---=> hardirq/softirq\n #                              || / _--=> preempt-depth\n #                              ||| / _-=> migrate-disable\n #                              |||| /     delay\n #           TASK-PID     CPU#  |||||  TIMESTAMP  FUNCTION\n #              | |         |   |||||     |         |\n      kworker/0:0-9       [000] .....     5.600194: pcie_ltssm_state_transition: dev: a40000000.pcie state: DETECT_ACT rate: Unknown\n      kworker/0:0-9       [000] .....     5.600198: pcie_ltssm_state_transition: dev: a40000000.pcie state: DETECT_WAIT rate: Unknown\n      kworker/0:0-9       [000] .....     5.600199: pcie_ltssm_state_transition: dev: a40000000.pcie state: DETECT_ACT rate: Unknown\n      kworker/0:0-9       [000] .....     5.600201: pcie_ltssm_state_transition: dev: a40000000.pcie state: POLL_ACTIVE rate: Unknown\n      kworker/0:0-9       [000] .....     5.600202: pcie_ltssm_state_transition: dev: a40000000.pcie state: POLL_CONFIG rate: Unknown\n      kworker/0:0-9       [000] .....     5.600204: pcie_ltssm_state_transition: dev: a40000000.pcie state: CFG_LINKWD_START rate: Unknown\n      kworker/0:0-9       [000] .....     5.600206: pcie_ltssm_state_transition: dev: a40000000.pcie state: CFG_LINKWD_ACEPT rate: Unknown\n      kworker/0:0-9       [000] .....     5.600207: pcie_ltssm_state_transition: dev: a40000000.pcie state: CFG_LANENUM_WAI rate: Unknown\n      kworker/0:0-9       [000] .....     5.600208: pcie_ltssm_state_transition: dev: a40000000.pcie state: CFG_LANENUM_ACEPT rate: Unknown\n      kworker/0:0-9       [000] .....     5.600210: pcie_ltssm_state_transition: dev: a40000000.pcie state: CFG_COMPLETE rate: Unknown\n      kworker/0:0-9       [000] .....     5.600212: pcie_ltssm_state_transition: dev: a40000000.pcie state: CFG_IDLE rate: Unknown\n      kworker/0:0-9       [000] .....     5.600213: pcie_ltssm_state_transition: dev: a40000000.pcie state: L0 rate: 2.5 GT/s\n      kworker/0:0-9       [000] .....     5.600214: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_LOCK rate: Unknown\n      kworker/0:0-9       [000] .....     5.600216: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_RCVRCFG rate: Unknown\n      kworker/0:0-9       [000] .....     5.600217: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_SPEED rate: Unknown\n      kworker/0:0-9       [000] .....     5.600218: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_LOCK rate: Unknown\n      kworker/0:0-9       [000] .....     5.600220: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_EQ1 rate: Unknown\n      kworker/0:0-9       [000] .....     5.600221: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_EQ2 rate: 8.0 GT/s\n      kworker/0:0-9       [000] .....     5.600222: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_EQ3 rate: 8.0 GT/s\n      kworker/0:0-9       [000] .....     5.600224: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_LOCK rate: 8.0 GT/s\n      kworker/0:0-9       [000] .....     5.600225: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_RCVRCFG rate: 8.0 GT/s\n      kworker/0:0-9       [000] .....     5.600226: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_IDLE rate: 8.0 GT/s\n      kworker/0:0-9       [000] .....     5.600227: pcie_ltssm_state_transition: dev: a40000000.pcie state: L0 rate: 8.0 GT/s\n      kworker/0:0-9       [000] .....     5.600228: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_LOCK rate: 8.0 GT/s\n      kworker/0:0-9       [000] .....     5.600229: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_RCVRCFG rate: 8.0 GT/s\n      kworker/0:0-9       [000] .....     5.600231: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_IDLE rate: 8.0 GT/s\n      kworker/0:0-9       [000] .....     5.600232: pcie_ltssm_state_transition: dev: a40000000.pcie state: L0 rate: 8.0 GT/s\n      kworker/0:0-9       [000] .....     5.600233: pcie_ltssm_state_transition: dev: a40000000.pcie state: L123_SEND_EIDLE rate: 8.0 GT/s\n      kworker/0:0-9       [000] .....     5.600234: pcie_ltssm_state_transition: dev: a40000000.pcie state: L1_IDLE rate: 8.0 GT/s\n      kworker/0:0-9       [000] .....     5.600236: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_LOCK rate: 8.0 GT/s\n      kworker/0:0-9       [000] .....     5.600237: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_RCVRCFG rate: 8.0 GT/s\n      kworker/0:0-9       [000] .....     5.600238: pcie_ltssm_state_transition: dev: a40000000.pcie state: RCVRY_IDLE rate: 8.0 GT/s\n      kworker/0:0-9       [000] .....     5.600239: pcie_ltssm_state_transition: dev: a40000000.pcie state: L0 rate: 8.0 GT/s\n\n\nChanges in v5:\n- rebase\n- use EM/EMe instead\n- remove reg/unreg function and back to use TRACE_EVENT\n- use trace_pcie_ltssm_state_transition_enabled()\n\nChanges in v4:\n- use TRACE_EVENT_FN to notify when to start and stop the tracepoint,\n  and export pci_ltssm_tp_enabled() for host drivers to use\n- skip trace if pci_ltssm_tp_enabled() is false.(Steven)\n- wrap into 80 columns(Bjorn)\n\nChanges in v3:\n- add TRACE_DEFINE_ENUM for all enums(Steven Rostedt)\n- Add toctree entry in Documentation/trace/index.rst(Bagas Sanjaya)\n- fix mismatch section underline length(Bagas Sanjaya)\n- Make example snippets in code block(Bagas Sanjaya)\n- warp context into 80 columns and fix the file name(Bjorn)\n- reorder variables(Mani)\n- rename loop to i; rename en to enable(Mani)\n- use FIELD_GET(Mani)\n- add comment about how the FIFO works(Mani)\n\nChanges in v2:\n- use tracepoint\n\nShawn Lin (3):\n  PCI: trace: Add PCI controller LTSSM transition tracepoint\n  Documentation: tracing: Add PCI controller event documentation\n  PCI: dw-rockchip: Add pcie_ltssm_state_transition trace support\n\n Documentation/trace/events-pci-controller.rst |  42 ++++++++++\n Documentation/trace/index.rst                 |   1 +\n drivers/pci/controller/dwc/pcie-dw-rockchip.c | 111 ++++++++++++++++++++++++++\n drivers/pci/trace.c                           |   1 +\n include/trace/events/pci_controller.h         |  58 ++++++++++++++\n 5 files changed, 213 insertions(+)\n create mode 100644 Documentation/trace/events-pci-controller.rst\n create mode 100644 include/trace/events/pci_controller.h"
}