kernel/linux.git/include/linux/pci-epf.h, branch v6.19.11

PCI: endpoint: Add BAR subrange mapping support

2026-02-26T23:01:10+00:00

[ Upstream commit 31fb95400451040050361e22ff480476964280f0 ] Some endpoint platforms have only a small number of usable BARs. At the same time, EPF drivers (e.g. vNTB) may need multiple independent inbound regions (control/scratchpad, one or more memory windows, and optionally MSI or other feature-related regions). Subrange mapping allows these to share a single BAR without consuming additional BARs that may not be available, or forcing a fragile layout by aggressively packing into a single contiguous memory range. Extend the PCI endpoint core to support mapping subranges within a BAR. Add an optional 'submap' field in struct pci_epf_bar so an endpoint function driver can request inbound mappings that fully cover the BAR. Introduce a new EPC feature bit, subrange_mapping, and reject submap requests from pci_epc_set_bar() unless the controller advertises both subrange_mapping and dynamic_inbound_mapping features. The submap array describes the complete BAR layout (no overlaps and no gaps are allowed to avoid exposing untranslated address ranges). This provides the generic infrastructure needed to map multiple logical regions into a single BAR at different offsets, without assuming a controller-specific inbound address translation mechanism. Signed-off-by: Koichiro Den Signed-off-by: Manivannan Sadhasivam Reviewed-by: Niklas Cassel Link: https://patch.msgid.link/20260124145012.2794108-3-den@valinux.co.jp Stable-dep-of: 72cb5ed2a5c6 ("PCI: dwc: ep: Add per-PF BAR and inbound ATU mapping support") Signed-off-by: Sasha Levin

PCI: endpoint: Add pci_epf_assign_bar_space() API

2025-10-27T15:08:20+00:00

Add pci_epf_assign_bar_space() API to allow setting any MMIO address as the BAR memory space, such as an MSI message base address. This API also conforms to the BAR base address and size alignment restrictions enforced by the PCI spec r6.0, sec 7.5.1.2.1. Signed-off-by: Frank Li [mani: removed unused epc var, reworded kdoc, comments and description] Signed-off-by: Manivannan Sadhasivam Link: https://patch.msgid.link/20251015-vntb_msi_doorbell-v6-3-9230298b1910@nxp.com

PCI: endpoint: Rename 'epf_bar::aligned_size' to 'epf_bar:mem_size'

2025-10-27T14:23:53+00:00

Rename the member 'epf_bar::aligned_size' to 'epf_bar::mem_size' to better reflect its purpose. 'aligned_size' was misleading, as it actually represents the backing memory size allocated for the BAR rather than the aligned size. Signed-off-by: Frank Li Signed-off-by: Manivannan Sadhasivam Reviewed-by: Niklas Cassel Link: https://patch.msgid.link/20251015-vntb_msi_doorbell-v6-1-9230298b1910@nxp.com

PCI: endpoint: Add pci_epf_align_inbound_addr() helper for inbound address alignment

2025-07-24T21:51:41+00:00

Add pci_epf_align_inbound_addr() to align the inbound addresses according to PCI BAR alignment requirements. The aligned base address and offset are returned via 'base' and 'off' parameters. Signed-off-by: Frank Li [mani: reworded kernel-doc and commit message] Signed-off-by: Manivannan Sadhasivam Signed-off-by: Bjorn Helgaas Tested-by: Niklas Cassel Link: https://patch.msgid.link/20250710-ep-msi-v21-5-57683fc7fb25@nxp.com

PCI: endpoint: Add RC-to-EP doorbell support using platform MSI controller

2025-07-24T21:51:17+00:00

Implement the doorbell feature by mapping the EP's MSI interrupt controller message address to a dedicated BAR. The EPF driver should pass the actual message data to be written to the message address by the host through implementation-specific logic. Signed-off-by: Frank Li [mani: minor code cleanups and reworded commit message] Signed-off-by: Manivannan Sadhasivam [bhelgaas: fix kernel-doc] Signed-off-by: Bjorn Helgaas Tested-by: Niklas Cassel Link: https://patch.msgid.link/20250710-ep-msi-v21-3-57683fc7fb25@nxp.com

PCI: endpoint: Retain fixed-size BAR size as well as aligned size

2025-05-28T21:15:40+00:00

When allocating space for an endpoint function on a BAR with a fixed size, the size saved in 'struct pci_epf_bar.size' should be the fixed size as expected by pci_epc_set_bar(). However, if pci_epf_alloc_space() increased the allocation size to accommodate iATU alignment requirements, it previously saved the larger aligned size in .size, which broke pci_epc_set_bar(). To solve this, keep the fixed BAR size in .size and save the aligned size in a new .aligned_size for use when deallocating it. Fixes: 2a9a801620ef ("PCI: endpoint: Add support to specify alignment for buffers allocated to BARs") Signed-off-by: Jerome Brunet [mani: commit message fixup] Signed-off-by: Manivannan Sadhasivam [bhelgaas: more specific subject, commit log, wrap comment to match file] Signed-off-by: Bjorn Helgaas Reviewed-by: Niklas Cassel Link: https://patch.msgid.link/20250424-pci-ep-size-alignment-v5-1-2d4ec2af23f5@baylibre.com

PCI: Fix typos

2025-03-08T21:08:45+00:00

Fix typos and whitespace errors. Link: https://lore.kernel.org/r/20250307231715.438518-1-helgaas@kernel.org Signed-off-by: Bjorn Helgaas

PCI: endpoint: Replace magic number '6' by PCI_STD_NUM_BARS

2024-12-12T18:59:11+00:00

Replace the constant "6" by PCI_STD_NUM_BARS, as defined in include/uapi/linux/pci_regs.h: #define PCI_STD_NUM_BARS 6 /* Number of standard BARs */ Link: https://lore.kernel.org/r/20241212162547.225880-1-rick.wertenbroek@gmail.com Signed-off-by: Rick Wertenbroek Signed-off-by: Bjorn Helgaas

Merge tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2024-07-25T17:42:22+00:00

Pull driver core updates from Greg KH: "Here is the big set of driver core changes for 6.11-rc1. Lots of stuff in here, with not a huge diffstat, but apis are evolving which required lots of files to be touched. Highlights of the changes in here are: - platform remove callback api final fixups (Uwe took many releases to get here, finally!) - Rust bindings for basic firmware apis and initial driver-core interactions. It's not all that useful for a "write a whole driver in rust" type of thing, but the firmware bindings do help out the phy rust drivers, and the driver core bindings give a solid base on which others can start their work. There is still a long way to go here before we have a multitude of rust drivers being added, but it's a great first step. - driver core const api changes. This reached across all bus types, and there are some fix-ups for some not-common bus types that linux-next and 0-day testing shook out. This work is being done to help make the rust bindings more safe, as well as the C code, moving toward the end-goal of allowing us to put driver structures into read-only memory. We aren't there yet, but are getting closer. - minor devres cleanups and fixes found by code inspection - arch_topology minor changes - other minor driver core cleanups All of these have been in linux-next for a very long time with no reported problems" * tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits) ARM: sa1100: make match function take a const pointer sysfs/cpu: Make crash_hotplug attribute world-readable dio: Have dio_bus_match() callback take a const * zorro: make match function take a const pointer driver core: module: make module_[add|remove]_driver take a const * driver core: make driver_find_device() take a const * driver core: make driver_[create|remove]_file take a const * firmware_loader: fix soundness issue in `request_internal` firmware_loader: annotate doctests as `no_run` devres: Correct code style for functions that return a pointer type devres: Initialize an uninitialized struct member devres: Fix memory leakage caused by driver API devm_free_percpu() devres: Fix devm_krealloc() wasting memory driver core: platform: Switch to use kmemdup_array() driver core: have match() callback in struct bus_type take a const * MAINTAINERS: add Rust device abstractions to DRIVER CORE device: rust: improve safety comments MAINTAINERS: add Danilo as FIRMWARE LOADER maintainer MAINTAINERS: add Rust FW abstractions to FIRMWARE LOADER firmware: rust: improve safety comments ...

PCI: endpoint: Introduce 'epc_deinit' event and notify the EPF drivers

2024-07-04T14:40:53+00:00

As like the 'epc_init' event, that is used to signal the EPF drivers about the EPC initialization, let's introduce 'epc_deinit' event that is used to signal EPC deinitialization. The EPC deinitialization applies only when any sort of fundamental reset is supported by the endpoint controller as per the PCIe spec. Reference: PCIe r6.0, sec 4.2.5.9.1 and 6.6.1. Currently, some EPC drivers like pcie-qcom-ep and pcie-tegra194 support PERST# as the fundamental reset. So the 'deinit' event will be notified to the EPF drivers when PERST# assert happens in the above mentioned EPC drivers. The EPF drivers, on receiving the event through the epc_deinit() callback should reset the EPF state machine and also cleanup any configuration that got affected by the fundamental reset like BAR, DMA etc... This change also warrants skipping the cleanups in unbind() if already done in epc_deinit(). Link: https://lore.kernel.org/r/20240606-pci-deinit-v1-2-4395534520dc@linaro.org Signed-off-by: Manivannan Sadhasivam Signed-off-by: Krzysztof Wilczyński Reviewed-by: Niklas Cassel Reviewed-by: Siddharth Vadapalli Reviewed-by: Frank Li