kernel/linux.git/include/uapi/linux/pci_regs.h, branch v6.12.80

PCI: Correct PCI_CAP_EXP_ENDPOINT_SIZEOF_V2 value

2026-03-13T16:20:20+00:00

[ Upstream commit 39195990e4c093c9eecf88f29811c6de29265214 ] fb82437fdd8c ("PCI: Change capability register offsets to hex") incorrectly converted the PCI_CAP_EXP_ENDPOINT_SIZEOF_V2 value from decimal 52 to hex 0x32: -#define PCI_CAP_EXP_ENDPOINT_SIZEOF_V2 52 /* v2 endpoints with link end here */ +#define PCI_CAP_EXP_ENDPOINT_SIZEOF_V2 0x32 /* end of v2 EPs w/ link */ This broke PCI capabilities in a VMM because subsequent ones weren't DWORD-aligned. Change PCI_CAP_EXP_ENDPOINT_SIZEOF_V2 to the correct value of 0x34. fb82437fdd8c was from Baruch Siach , but this was not Baruch's fault; it's a mistake I made when applying the patch. Fixes: fb82437fdd8c ("PCI: Change capability register offsets to hex") Reported-by: David Woodhouse Closes: https://lore.kernel.org/all/3ae392a0158e9d9ab09a1d42150429dd8ca42791.camel@infradead.org Signed-off-by: Bjorn Helgaas Reviewed-by: Krzysztof Wilczyński Signed-off-by: Sasha Levin

PCI: Store all PCIe Supported Link Speeds

2025-08-20T16:30:57+00:00

[ Upstream commit d2bd39c0456b75be9dfc7d774b8d021355c26ae3 ] The PCIe bandwidth controller added by a subsequent commit will require selecting PCIe Link Speeds that are lower than the Maximum Link Speed. The struct pci_bus only stores max_bus_speed. Even if PCIe r6.1 sec 8.2.1 currently disallows gaps in supported Link Speeds, the Implementation Note in PCIe r6.1 sec 7.5.3.18, recommends determining supported Link Speeds using the Supported Link Speeds Vector in the Link Capabilities 2 Register (when available) to "avoid software being confused if a future specification defines Links that do not require support for all slower speeds." Reuse code in pcie_get_speed_cap() to add pcie_get_supported_speeds() to query the Supported Link Speeds Vector of a PCIe device. The value is taken directly from the Supported Link Speeds Vector or synthesized from the Max Link Speed in the Link Capabilities Register when the Link Capabilities 2 Register is not available. The Supported Link Speeds Vector in the Link Capabilities Register 2 corresponds to the bus below on Root Ports and Downstream Ports, whereas it corresponds to the bus above on Upstream Ports and Endpoints (PCIe r6.1 sec 7.5.3.18): Supported Link Speeds Vector - This field indicates the supported Link speed(s) of the associated Port. Add supported_speeds into the struct pci_dev that caches the Supported Link Speeds Vector. supported_speeds contains a set of Link Speeds only in the case where PCIe Link Speed can be determined. Root Complex Integrated Endpoints do not have a well-defined Link Speed because they do not implement either of the Link Capabilities Registers, which is allowed by PCIe r6.1 sec 7.5.3 (the same limitation applies to determining cur_bus_speed and max_bus_speed that are PCI_SPEED_UNKNOWN in such case). This is of no concern from PCIe bandwidth controller point of view because such devices are not attached into a PCIe Root Port that could be controlled. The supported_speeds field keeps the extra reserved zero at the least significant bit to match the Link Capabilities 2 Register layout. An attempt was made to store supported_speeds field into the struct pci_bus as an intersection of both ends of the Link, however, the subordinate struct pci_bus is not available early enough. The Target Speed quirk (in pcie_failed_link_retrain()) can run either during initial scan or later, requiring it to use the API provided by the PCIe bandwidth controller to set the Target Link Speed in order to co-exist with the bandwidth controller. When the Target Speed quirk is calling the bandwidth controller during initial scan, the struct pci_bus is not yet initialized. As such, storing supported_speeds into the struct pci_bus is not viable. Suggested-by: Lukas Wunner Link: https://lore.kernel.org/r/20241018144755.7875-4-ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen [bhelgaas: move pcie_get_supported_speeds() decl to drivers/pci/pci.h] Signed-off-by: Bjorn Helgaas Reviewed-by: Jonathan Cameron Stable-dep-of: 6cff20ce3b92 ("PCI/ACPI: Fix runtime PM ref imbalance on Hot-Plug Capable ports") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

Merge branch 'pci/npem'

2024-09-19T19:25:26+00:00

- Initialize leds class earlier (with an unfortunate Makefile ordering change) so the PCI NPEM driver can use it (Mariusz Tkaczyk) - Add Native PCIe Enclosure Management (NPEM) support for sysfs control of NVMe RAID storage indicators (ok/fail/locate/rebuild/etc) (Mariusz Tkaczyk) - Add support for the ACPI _DSM PCIe SSD status LED management, which is functionally similar to NPEM but mediated by platform firmware (Mariusz Tkaczyk) * pci/npem: PCI/NPEM: Add _DSM PCIe SSD status LED management PCI/NPEM: Add Native PCIe Enclosure Management support leds: Init leds class earlier

PCI: Rename CRS Completion Status to RRS

2024-09-11T00:52:30+00:00

PCIe r6.0 changed the abbreviation for "Configuration Request Retry Status" Completion Status from "CRS" to "RRS" and uses the terminology of "Configuration RRS Software Visibility" instead of "CRS Software Visibility". Align the Linux usage with the r6.0 spec language. No functional change intended. It's confusing to make this change, but I think "RRS" *is* a better abbreviation because it was easy to interpret "CRS" as "Completion Retry Status", which really didn't make any sense. Link: https://lore.kernel.org/r/20240827234848.4429-4-helgaas@kernel.org Signed-off-by: Bjorn Helgaas

PCI/NPEM: Add Native PCIe Enclosure Management support

2024-09-04T22:25:12+00:00

Native PCIe Enclosure Management (NPEM, PCIe r6.1 sec 6.28) allows managing LEDs in storage enclosures. NPEM is indication oriented and it does not give direct access to LEDs. Although each indication *could* represent an individual LED, multiple indications could also be represented as a single, multi-color LED or a single LED blinking in a specific interval. The specification leaves that open. Each enabled indication (capability register bit on) is represented as a ledclass_dev which can be controlled through sysfs. For every ledclass device only 2 brightness states are allowed: LED_ON (1) or LED_OFF (0). This corresponds to the NPEM control register (Indication bit on/off). Ledclass devices appear in sysfs as child devices (subdirectory) of PCI device which has an NPEM Extended Capability and indication is enabled in NPEM capability register. For example, these are LEDs created for pcieport "10000:02:05.0" on my setup: leds/ ├── 10000:02:05.0:enclosure:fail ├── 10000:02:05.0:enclosure:locate ├── 10000:02:05.0:enclosure:ok └── 10000:02:05.0:enclosure:rebuild They can be also found in "/sys/class/leds" directory. The parent PCIe device domain/bus/device/function address is used to guarantee uniqueness across leds subsystem. To enable/disable a "fail" indication, the "brightness" file can be edited: echo 1 > ./leds/10000:02:05.0:enclosure:fail/brightness echo 0 > ./leds/10000:02:05.0:enclosure:fail/brightness PCIe r6.1, sec 7.9.19.2 defines the possible indications. Multiple indications for same parent PCIe device can conflict and hardware may update them when processing new request. To avoid issues, driver refresh all indications by reading back control register. This driver expects to be the exclusive NPEM extended capability manager. It waits up to 1 second after imposing new request, it doesn't verify if controller is busy before write, and it assumes the mutex lock gives protection from concurrent updates. If _DSM LED management is available, we assume the platform may be using NPEM for its own purposes (see PCI Firmware Spec r3.3 sec 4.7), so the driver does not use NPEM. A future patch will add _DSM support; an info message notes whether NPEM or _DSM is being used. NPEM is a PCIe extended capability so it should be registered in pcie_init_capabilities() but it is not possible due to LED dependency. The parent pci_device must be added earlier for led_classdev_register() to be successful. NPEM does not require configuration on kernel side, so it is safe to register LED devices later. Link: https://lore.kernel.org/r/20240904104848.23480-3-mariusz.tkaczyk@linux.intel.com Suggested-by: Lukas Wunner Signed-off-by: Mariusz Tkaczyk Signed-off-by: Bjorn Helgaas Tested-by: Stuart Hayes Reviewed-by: Christoph Hellwig Reviewed-by: Ilpo Järvinen

Merge branch 'pci/doe'

2024-05-16T23:14:09+00:00

- Add support for DOE Discovery version 2 (Alexey Kardashevskiy) * pci/doe: PCI/DOE: Support discovery version 2

PCI/CXL: Fail bus reset if upstream CXL Port has SBR masked

2024-05-08T18:25:36+00:00

Per CXL spec r3.1, sec 8.1.5.2, the Secondary Bus Reset (SBR) bit in the Bridge Control register of a CXL port has no effect unless the "Unmask SBR" bit is set. Return -ENOTTY if we attempt a bus reset on a device below a CXL Port where "Unmask SBR" is 0. Otherwise, the bus reset would appear to have succeeded even though setting the bridge SBR bit had no effect. Link: https://lore.kernel.org/linux-cxl/20240220203956.GA1502351@bhelgaas/ Link: https://lore.kernel.org/r/20240502165851.1948523-4-dave.jiang@intel.com Signed-off-by: Dave Jiang [bhelgaas: simplify commit log and comments] Signed-off-by: Bjorn Helgaas Reviewed-by: Jonathan Cameron Reviewed-by: Kuppuswamy Sathyanarayanan Reviewed-by: Dan Williams

PCI/DOE: Support discovery version 2

2024-04-09T14:33:15+00:00

PCIe r6.1, sec 6.30.1.1 defines a "DOE Discovery Version" field in the DOE Discovery Request Data Object Contents (3rd DW) as: 15:8 DOE Discovery Version – must be 02h if the Capability Version in the Data Object Exchange Extended Capability is 02h or greater. Add support for the version on devices with the DOE v2 capability. Link: https://lore.kernel.org/r/20240307022006.3657433-1-aik@amd.com Signed-off-by: Alexey Kardashevskiy Signed-off-by: Bjorn Helgaas Reviewed-by: Kuppuswamy Sathyanarayanan

Merge branch 'pci/field-get'

2023-10-28T18:31:05+00:00

- Use FIELD_GET()/FIELD_PREP() when possible throughout drivers/pci/ (Ilpo Järvinen, Bjorn Helgaas) - Rework DPC control programming for clarity (Ilpo Järvinen) * pci/field-get: PCI/portdrv: Use FIELD_GET() PCI/VC: Use FIELD_GET() PCI/PTM: Use FIELD_GET() PCI/PME: Use FIELD_GET() PCI/ATS: Use FIELD_GET() PCI/ATS: Show PASID Capability register width in bitmasks PCI: Use FIELD_GET() in Sapphire RX 5600 XT Pulse quirk PCI: Use FIELD_GET() PCI/MSI: Use FIELD_GET/PREP() PCI/DPC: Use defines with DPC reason fields PCI/DPC: Use defined fields with DPC_CTL register PCI/DPC: Use FIELD_GET() PCI: hotplug: Use FIELD_GET/PREP() PCI: dwc: Use FIELD_GET/PREP() PCI: cadence: Use FIELD_GET() PCI: Use FIELD_GET() to extract Link Width PCI: mvebu: Use FIELD_PREP() with Link Width PCI: tegra194: Use FIELD_GET()/FIELD_PREP() with Link Width fields # Conflicts: # drivers/pci/controller/dwc/pcie-tegra194.c

Merge branch 'pci/enumeration'

2023-10-28T18:30:58+00:00

- Add and use pci_get_base_class() to search for all PCI_BASE_CLASS_DISPLAY devices (Sui Jingfeng) - Fix a vmd check for multi-function devices (Ilpo Järvinen) - Add PCI_HEADER_TYPE_MFD and use it to replace literals (Ilpo Järvinen) - Use acpi_evaluate_dsm_typed() instead of open-coding it (Andy Shevchenko) - Keep .remove() and .probe() callbacks (previously marked __init) in case they're used via sysfs (Uwe Kleine-König) * pci/enumeration: PCI: keystone: Don't discard .probe() callback PCI: keystone: Don't discard .remove() callback PCI: kirin: Don't discard .remove() callback PCI: exynos: Don't discard .remove() callback PCI/ACPI: Use acpi_evaluate_dsm_typed() PCI: Use PCI_HEADER_TYPE_* instead of literals PCI: Add PCI_HEADER_TYPE_MFD definition PCI: vmd: Correct PCI Header Type Register's multi-function check drm/radeon: Use pci_get_base_class() to reduce duplicated code drm/amdgpu: Use pci_get_base_class() to reduce duplicated code drm/nouveau: Use pci_get_base_class() to reduce duplicated code ALSA: hda: Use pci_get_base_class() to reduce duplicated code PCI: Add pci_get_base_class() helper