Merge tag 'pci-v5.16-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull pci updates from Bjorn Helgaas:
 "Enumeration:
   - Conserve IRQs by setting up portdrv IRQs only when there are users
     (Jan Kiszka)
   - Rework and simplify _OSC negotiation for control of PCIe features
     (Joerg Roedel)
   - Remove struct pci_dev.driver pointer since it's redundant with the
     struct device.driver pointer (Uwe Kleine-König)

  Resource management:
   - Coalesce contiguous host bridge apertures from _CRS to accommodate
     BARs that cover more than one aperture (Kai-Heng Feng)

  Sysfs:
   - Check CAP_SYS_ADMIN before parsing user input (Krzysztof
     Wilczyński)
   - Return -EINVAL consistently from "store" functions (Krzysztof
     Wilczyński)
   - Use sysfs_emit() in endpoint "show" functions to avoid buffer
     overruns (Kunihiko Hayashi)

  PCIe native device hotplug:
   - Ignore Link Down/Up caused by resets during error recovery so
     endpoint drivers can remain bound to the device (Lukas Wunner)

  Virtualization:
   - Avoid bus resets on Atheros QCA6174, where they hang the device
     (Ingmar Klein)
   - Work around Pericom PI7C9X2G switch packet drop erratum by using
     store and forward mode instead of cut-through (Nathan Rossi)
   - Avoid trying to enable AtomicOps on VFs; the PF setting applies to
     all VFs (Selvin Xavier)

  MSI:
   - Document that /sys/bus/pci/devices/.../irq contains the legacy INTx
     interrupt or the IRQ of the first MSI (not MSI-X) vector (Barry
     Song)

  VPD:
   - Add pci_read_vpd_any() and pci_write_vpd_any() to access anywhere
     in the possible VPD space; use these to simplify the cxgb3 driver
     (Heiner Kallweit)

  Peer-to-peer DMA:
   - Add (not subtract) the bus offset when calculating DMA address
     (Wang Lu)

  ASPM:
   - Re-enable LTR at Downstream Ports so they don't report Unsupported
     Requests when reset or hot-added devices send LTR messages
     (Mingchuang Qiao)

  Apple PCIe controller driver:
   - Add driver for Apple M1 PCIe controller (Alyssa Rosenzweig, Marc
     Zyngier)

  Cadence PCIe controller driver:
   - Return success when probe succeeds instead of falling into error
     path (Li Chen)

  HiSilicon Kirin PCIe controller driver:
   - Reorganize PHY logic and add support for external PHY drivers
     (Mauro Carvalho Chehab)
   - Support PERST# GPIOs for HiKey970 external PEX 8606 bridge (Mauro
     Carvalho Chehab)
   - Add Kirin 970 support (Mauro Carvalho Chehab)
   - Make driver removable (Mauro Carvalho Chehab)

  Intel VMD host bridge driver:
   - If IOMMU supports interrupt remapping, leave VMD MSI-X remapping
     enabled (Adrian Huang)
   - Number each controller so we can tell them apart in
     /proc/interrupts (Chunguang Xu)
   - Avoid building on UML because VMD depends on x86 bare metal APIs
     (Johannes Berg)

  Marvell Aardvark PCIe controller driver:
   - Define macros for PCI_EXP_DEVCTL_PAYLOAD_* (Pali Rohár)
   - Set Max Payload Size to 512 bytes per Marvell spec (Pali Rohár)
   - Downgrade PIO Response Status messages to debug level (Marek Behún)
   - Preserve CRS SV (Config Request Retry Software Visibility) bit in
     emulated Root Control register (Pali Rohár)
   - Fix issue in configuring reference clock (Pali Rohár)
   - Don't clear status bits for masked interrupts (Pali Rohár)
   - Don't mask unused interrupts (Pali Rohár)
   - Avoid code repetition in advk_pcie_rd_conf() (Marek Behún)
   - Retry config accesses on CRS response (Pali Rohár)
   - Simplify emulated Root Capabilities initialization (Pali Rohár)
   - Fix several link training issues (Pali Rohár)
   - Fix link-up checking via LTSSM (Pali Rohár)
   - Fix reporting of Data Link Layer Link Active (Pali Rohár)
   - Fix emulation of W1C bits (Marek Behún)
   - Fix MSI domain .alloc() method to return zero on success (Marek
     Behún)
   - Read entire 16-bit MSI vector in MSI handler, not just low 8 bits
     (Marek Behún)
   - Clear Root Port I/O Space, Memory Space, and Bus Master Enable bits
     at startup; PCI core will set those as necessary (Pali Rohár)
   - When operating as a Root Port, set class code to "PCI Bridge"
     instead of the default "Mass Storage Controller" (Pali Rohár)
   - Add emulation for PCI_BRIDGE_CTL_BUS_RESET since aardvark doesn't
     implement this per spec (Pali Rohár)
   - Add emulation of option ROM BAR since aardvark doesn't implement
     this per spec (Pali Rohár)

  MediaTek MT7621 PCIe controller driver:
   - Add MediaTek MT7621 PCIe host controller driver and DT binding
     (Sergio Paracuellos)

  Qualcomm PCIe controller driver:
   - Add SC8180x compatible string (Bjorn Andersson)
   - Add endpoint controller driver and DT binding (Manivannan
     Sadhasivam)
   - Restructure to use of_device_get_match_data() (Prasad Malisetty)
   - Add SC7280-specific pcie_1_pipe_clk_src handling (Prasad Malisetty)

  Renesas R-Car PCIe controller driver:
   - Remove unnecessary includes (Geert Uytterhoeven)

  Rockchip DesignWare PCIe controller driver:
   - Add DT binding (Simon Xue)

  Socionext UniPhier Pro5 controller driver:
   - Serialize INTx masking/unmasking (Kunihiko Hayashi)

  Synopsys DesignWare PCIe controller driver:
   - Run dwc .host_init() method before registering MSI interrupt
     handler so we can deal with pending interrupts left by bootloader
     (Bjorn Andersson)
   - Clean up Kconfig dependencies (Andy Shevchenko)
   - Export symbols to allow more modular drivers (Luca Ceresoli)

  TI DRA7xx PCIe controller driver:
   - Allow host and endpoint drivers to be modules (Luca Ceresoli)
   - Enable external clock if present (Luca Ceresoli)

  TI J721E PCIe driver:
   - Disable PHY when probe fails after initializing it (Christophe
     JAILLET)

  MicroSemi Switchtec management driver:
   - Return error to application when command execution fails because an
     out-of-band reset has cleared the device BARs, Memory Space Enable,
     etc (Kelvin Cao)
   - Fix MRPC error status handling issue (Kelvin Cao)
   - Mask out other bits when reading of management VEP instance ID
     (Kelvin Cao)
   - Return EOPNOTSUPP instead of ENOTSUPP from sysfs show functions
     (Kelvin Cao)
   - Add check of event support (Logan Gunthorpe)

  Miscellaneous:
   - Remove unused pci_pool wrappers, which have been replaced by
     dma_pool (Cai Huoqing)
   - Use 'unsigned int' instead of bare 'unsigned' (Krzysztof
     Wilczyński)
   - Use kstrtobool() directly, sans strtobool() wrapper (Krzysztof
     Wilczyński)
   - Fix some sscanf(), sprintf() format mismatches (Krzysztof
     Wilczyński)
   - Update PCI subsystem information in MAINTAINERS (Krzysztof
     Wilczyński)
   - Correct some misspellings (Krzysztof Wilczyński)"

* tag 'pci-v5.16-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (137 commits)
  PCI: Add ACS quirk for Pericom PI7C9X2G switches
  PCI: apple: Configure RID to SID mapper on device addition
  iommu/dart: Exclude MSI doorbell from PCIe device IOVA range
  PCI: apple: Implement MSI support
  PCI: apple: Add INTx and per-port interrupt support
  PCI: kirin: Allow removing the driver
  PCI: kirin: De-init the dwc driver
  PCI: kirin: Disable clkreq during poweroff sequence
  PCI: kirin: Move the power-off code to a common routine
  PCI: kirin: Add power_off support for Kirin 960 PHY
  PCI: kirin: Allow building it as a module
  PCI: kirin: Add MODULE_* macros
  PCI: kirin: Add Kirin 970 compatible
  PCI: kirin: Support PERST# GPIOs for HiKey970 external PEX 8606 bridge
  PCI: apple: Set up reference clocks when probing
  PCI: apple: Add initial hardware bring-up
  PCI: of: Allow matching of an interrupt-map local to a PCI device
  of/irq: Allow matching of an interrupt-map local to an interrupt controller
  irqdomain: Make of_phandle_args_to_fwspec() generally available
  PCI: Do not enable AtomicOps on VFs
  ...

1 files changed, 11 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
index 16afe3f59cbd..6fc2c2efe8ab 100644
--- a/Documentation/ABI/testing/sysfs-bus-pci
+++ b/Documentation/ABI/testing/sysfs-bus-pci
@@ -100,6 +100,17 @@ Description:
 		This attribute indicates the mode that the irq vector named by
 		the file is in (msi vs. msix)
 
+What:		/sys/bus/pci/devices/.../irq
+Date:		August 2021
+Contact:	Linux PCI developers <linux-pci@vger.kernel.org>
+Description:
+		If a driver has enabled MSI (not MSI-X), "irq" contains the
+		IRQ of the first MSI vector. Otherwise "irq" contains the
+		IRQ of the legacy INTx interrupt.
+
+		"irq" being set to 0 indicates that the device isn't
+		capable of generating legacy INTx interrupts.
+
 What:		/sys/bus/pci/devices/.../remove
 Date:		January 2009
 Contact:	Linux PCI developers <linux-pci@vger.kernel.org>