kernel.git/drivers/pci/probe.c, branch linux-6.9.y

Merge branch 'pci/sysfs'

2024-03-12T17:14:23Z

- Compile pci-sysfs.c only if CONFIG_SYSFS=y, which reduces kernel size by ~120KB when it's disabled (Lukas Wunner) - Remove obsolete pci_cleanup_rom() declaration (Lukas Wunner) - Rework pci_dev_resource_resize_attr(n) macros to call a function instead of duplicating most of the body, which saves about 2.5KB of text (Ilpo Järvinen) * pci/sysfs: PCI/sysfs: Demacrofy pci_dev_resource_resize_attr(n) functions PCI: Remove obsolete pci_cleanup_rom() declaration PCI/sysfs: Compile pci-sysfs.c only if CONFIG_SYSFS=y # Conflicts: # drivers/pci/Makefile

PCI/ASPM: Save L1 PM Substates Capability for suspend/resume

2024-03-12T16:53:45Z

4ff116d0d5fd ("PCI/ASPM: Save L1 PM Substates Capability for suspend/resume") restored the L1 PM Substates Capability after resume, which reduced power consumption by making the ASPM L1.x states work after resume. a7152be79b62 ("Revert "PCI/ASPM: Save L1 PM Substates Capability for suspend/resume"") reverted 4ff116d0d5fd because resume failed on some systems, so power consumption after resume increased again. a7152be79b62 mentioned that we restore L1 PM substate configuration even though ASPM L1 may already be enabled. This is due the fact that the pci_restore_aspm_l1ss_state() was called before pci_restore_pcie_state(). Save and restore the L1 PM Substates Capability, following PCIe r6.1, sec 5.5.4 more closely by: 1) Do not restore ASPM configuration in pci_restore_pcie_state() but do that after PCIe capability is restored in pci_restore_aspm_state() following PCIe r6.1, sec 5.5.4. 2) If BIOS reenables L1SS, particularly L1.2, we need to clear the enables in the right order, downstream before upstream. Defer restoring the L1SS config until we are at the downstream component. Then update the config for both ends of the link in the prescribed order. 3) Program ASPM L1 PM substate configuration before L1 enables. 4) Program ASPM L1 PM substate enables last, after rest of the fields in the capability are programmed. [bhelgaas: commit log, squash L1SS-related patches, do both LNKCTL restores in pci_restore_pcie_state()] Link: https://lore.kernel.org/r/20240128233212.1139663-3-david.e.box@linux.intel.com Link: https://lore.kernel.org/r/20240128233212.1139663-4-david.e.box@linux.intel.com Link: https://lore.kernel.org/r/20240223205851.114931-5-helgaas@kernel.org Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217321 Link: https://bugzilla.kernel.org/show_bug.cgi?id=216782 Link: https://bugzilla.kernel.org/show_bug.cgi?id=216877 Co-developed-by: Mika Westerberg Co-developed-by: David E. Box Reported-by: Koba Ko Signed-off-by: Mika Westerberg Signed-off-by: David E. Box Signed-off-by: Bjorn Helgaas Tested-by: Tasev Nikola # Asus UX305FA Cc: Mark Enriquez Cc: Thomas Witt Cc: Werner Sembach Cc: Vidya Sagar

PCI/ASPM: Move pci_configure_ltr() to aspm.c

2024-03-07T20:29:08Z

The Latency Tolerance Reporting (LTR) mechanism supports the ASPM L1.2 state and is only configured when CONFIG_PCIEASPM is set. Move pci_configure_ltr() and pci_bridge_reconfigure_ltr() into aspm.c since they only build when CONFIG_PCIEASPM is set. No functional change intended. Suggested-by: Bjorn Helgaas Link: https://lore.kernel.org/r/20240128233212.1139663-2-david.e.box@linux.intel.com [bhelgaas: commit log, split build change from function moves] Link: https://lore.kernel.org/r/20240223205851.114931-2-helgaas@kernel.org Signed-off-by: David E. Box Signed-off-by: Bjorn Helgaas

PCI/sysfs: Compile pci-sysfs.c only if CONFIG_SYSFS=y

2024-03-05T22:08:43Z

It is possible to enable CONFIG_PCI but disable CONFIG_SYSFS and for space-constrained devices such as routers, such a configuration may actually make sense. However pci-sysfs.c is compiled even if CONFIG_SYSFS is disabled, unnecessarily increasing the kernel's size. To rectify that: * Move pci_mmap_fits() to mmap.c. It is not only needed by pci-sysfs.c, but also proc.c. * Move pci_dev_type to probe.c and make it private. It references pci_dev_attr_groups in pci-sysfs.c. Make that public instead for consistency with pci_dev_groups, pcibus_groups and pci_bus_groups, which are likewise public and referenced by struct definitions in pci-driver.c and probe.c. * Define pci_dev_groups, pci_dev_attr_groups, pcibus_groups and pci_bus_groups to NULL if CONFIG_SYSFS is disabled. Provide empty static inlines for pci_{create,remove}_legacy_files() and pci_{create,remove}_sysfs_dev_files(). Result: vmlinux size is reduced by 122996 bytes in my arm 32-bit test build. Link: https://lore.kernel.org/r/85ca95ae8e4d57ccf082c5c069b8b21eb141846e.1698668982.git.lukas@wunner.de Signed-off-by: Lukas Wunner Signed-off-by: Bjorn Helgaas Reviewed-by: Alistair Francis

PCI: Log bridge info when first enumerating bridge

2023-12-15T23:28:43Z

Log bridge secondary/subordinate bus and window information at the same time we log the bridge BARs, just after discovering the bridge and before scanning the bridge's secondary bus. This logs the bridge and downstream devices in a more logical order: - pci 0000:00:01.0: [8086:1901] type 01 class 0x060400 - pci 0000:01:00.0: [10de:13b6] type 00 class 0x030200 - pci 0000:01:00.0: reg 0x10: [mem 0xec000000-0xecffffff] - pci 0000:00:01.0: PCI bridge to [bus 01] - pci 0000:00:01.0: bridge window [io 0xe000-0xefff] + pci 0000:00:01.0: [8086:1901] type 01 class 0x060400 + pci 0000:00:01.0: PCI bridge to [bus 01] + pci 0000:00:01.0: bridge window [io 0xe000-0xefff] + pci 0000:01:00.0: [10de:13b6] type 00 class 0x030200 + pci 0000:01:00.0: reg 0x10: [mem 0xec000000-0xecffffff] Note that we read the windows into a temporary struct resource that is thrown away, not into the resources in the struct pci_bus. The windows may be adjusted after we know what downstream devices require, and those adjustments are logged as they are made. Signed-off-by: Bjorn Helgaas

PCI: Log bridge windows conditionally

2023-12-15T23:28:43Z

Previously pci_read_bridge_io(), pci_read_bridge_mmio(), and pci_read_bridge_mmio_pref() unconditionally logged the bridge window resource. A future change will call these functions earlier and more often. Add a "log" parameter so callers can control whether to generate the log message. No functional change intended. Signed-off-by: Bjorn Helgaas

PCI: Supply bridge device, not secondary bus, to read window details

2023-12-15T23:28:43Z

Previously we logged information about devices *below* the bridge before logging information about the bridge itself, e.g., pci 0000:00:01.0: [8086:1901] type 01 class 0x060400 pci 0000:01:00.0: [10de:13b6] type 00 class 0x030200 pci 0000:01:00.0: reg 0x10: [mem 0xec000000-0xecffffff] pci 0000:00:01.0: PCI bridge to [bus 01] pci 0000:00:01.0: bridge window [io 0xe000-0xefff] This is partly because the bridge windows are read in this path: pci_scan_child_bus_extend for (devfn = 0; devfn < 256; devfn += 8) pci_scan_slot(bus, devfn) # scan below bridge pcibios_fixup_bus(bus) pci_read_bridge_bases(bus) # read bridge windows pci_read_bridge_io(bus) Remove the assumption that the secondary (child) pci_bus already exists by passing in the bridge device (instead of the pci_bus) and a resource pointer when reading bridge windows. A future change can use this to log the bridge details before we enumerate the devices below the bridge. No functional change intended. Signed-off-by: Bjorn Helgaas

PCI: Move pci_read_bridge_windows() below individual window accessors

2023-12-15T23:28:43Z

Move pci_read_bridge_windows() below the functions that read the I/O, memory, and prefetchable memory windows, so pci_read_bridge_windows() can use them in the future. No functional change intended. Signed-off-by: Bjorn Helgaas

PCI: Use resource names in PCI log messages

2023-12-15T23:28:42Z

Use the pci_resource_name() to get the name of the resource and use it while printing log messages. [bhelgaas: rename to match struct resource * names, also use names in other BAR messages] Link: https://lore.kernel.org/r/20211106112606.192563-3-puranjay12@gmail.com Signed-off-by: Puranjay Mohan Signed-off-by: Bjorn Helgaas

PCI: Log device type during enumeration

2023-12-15T23:26:21Z

Log the device type when enumeration a device. Sample output changes: - pci 0000:00:00.0: [8086:1237] type 00 class 0x060000 + pci 0000:00:00.0: [8086:1237] type 00 class 0x060000 conventional PCI endpoint - pci 0000:00:1c.0: [8086:a110] type 01 class 0x060400 + pci 0000:00:1c.0: [8086:a110] type 01 class 0x060400 PCIe Root Port Signed-off-by: Bjorn Helgaas