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Bjorn Helgaas 93c398be49 Merge branch 'pci/controller/dwc'
- Extend PCI_FIND_NEXT_CAP() and PCI_FIND_NEXT_EXT_CAP() to return a
  pointer to the preceding Capability (Qiang Yu)

- Add dw_pcie_remove_capability() and dw_pcie_remove_ext_capability() to
  remove Capabilities that are advertised but not fully implemented (Qiang
  Yu)

- Remove MSI and MSI-X Capabilities for DWC controllers in platforms that
  can't support them, so we automatically fall back to INTx (Qiang Yu)

- Remove MSI-X and DPC Capabilities for Qualcomm platforms that advertise
  but don't support them (Qiang Yu)

- Remove duplicate dw_pcie_ep_hide_ext_capability() function and replace
  with dw_pcie_remove_ext_capability() (Qiang Yu)

- Add ASPM L1.1 and L1.2 Substates context to debugfs ltssm_status for
  drivers that support this (Shawn Lin)

- Skip PME_Turn_Off broadcast and L2/L3 transition during suspend if link
  is not up to avoid an unnecessary timeout (Manivannan Sadhasivam)

- Revert dw-rockchip, qcom, and DWC core changes that used link-up IRQs to
  trigger enumeration instead of waiting for link to be up because the PCI
  core doesn't allocate bus number space for hierarchies that might be
  attached (Niklas Cassel)

- Make endpoint iATU entry for MSI permanent instead of programming it
  dynamically, which is slow and racy with respect to other concurrent
  traffic, e.g., eDMA (Koichiro Den)

- Use iMSI-RX MSI target address when possible to fix endpoints using
  32-bit MSI (Shawn Lin)

- Make dw_pcie_ltssm_status_string() available and use it for logging
  errors in dw_pcie_wait_for_link() (Manivannan Sadhasivam)

- Return -ENODEV when dw_pcie_wait_for_link() finds no devices, -EIO for
  device present but inactive, -ETIMEDOUT for other failures, so callers
  can handle these cases differently (Manivannan Sadhasivam)

- Allow DWC host controller driver probe to continue if device is not found
  or found but inactive; only fail when there's an error with the link
  (Manivannan Sadhasivam)

- For controllers like NXP i.MX6QP and i.MX7D, where LTSSM registers are
  not accessible after PME_Turn_Off, simply wait 10ms instead of polling
  for L2/L3 Ready (Richard Zhu)

- Use multiple iATU entries to map large bridge windows and DMA ranges when
  necessary instead of failing (Samuel Holland)

- Rename struct dw_pcie_rp.has_msi_ctrl to .use_imsi_rx for clarity (Qiang
  Yu)

- Add EPC dynamic_inbound_mapping feature bit for Endpoint Controllers that
  can update BAR inbound address translation without requiring EPF driver
  to clear/reset the BAR first, and advertise it for DWC-based Endpoints
  (Koichiro Den)

- Add EPC subrange_mapping feature bit for Endpoint Controllers that can
  map multiple independent inbound regions in a single BAR, implement
  subrange mapping, advertise it for DWC-based Endpoints, and add Endpoint
  selftests for it (Koichiro Den)

- Allow overriding default BAR sizes for pci-epf-test (Niklas Cassel)

- Make resizable BARs work for Endpoint multi-PF configurations; previously
  it only worked for PF 0 (Aksh Garg)

- Fix Endpoint non-PF 0 support for BAR configuration, ATU mappings, and
  Address Match Mode (Aksh Garg)

- Fix issues with outbound iATU index assignment that caused iATU index to
  be out of bounds (Niklas Cassel)

- Clean up iATU index tracking to be consistent (Niklas Cassel)

- Set up iATU when ECAM is enabled; previously IO and MEM outbound windows
  weren't programmed, and ECAM-related iATU entries weren't restored after
  suspend/resume, so config accesses failed (Krishna Chaitanya Chundru)

* pci/controller/dwc:
  PCI: dwc: Fix missing iATU setup when ECAM is enabled
  PCI: dwc: Clean up iATU index usage in dw_pcie_iatu_setup()
  PCI: dwc: Fix msg_atu_index assignment
  PCI: dwc: ep: Add comment explaining controller level PTM access in multi PF setup
  PCI: dwc: ep: Add per-PF BAR and inbound ATU mapping support
  PCI: dwc: ep: Fix resizable BAR support for multi-PF configurations
  PCI: endpoint: pci-epf-test: Allow overriding default BAR sizes
  selftests: pci_endpoint: Add BAR subrange mapping test case
  misc: pci_endpoint_test: Add BAR subrange mapping test case
  PCI: endpoint: pci-epf-test: Add BAR subrange mapping test support
  Documentation: PCI: endpoint: Clarify pci_epc_set_bar() usage
  PCI: dwc: ep: Support BAR subrange inbound mapping via Address Match Mode iATU
  PCI: dwc: Advertise dynamic inbound mapping support
  PCI: endpoint: Add BAR subrange mapping support
  PCI: endpoint: Add dynamic_inbound_mapping EPC feature
  PCI: dwc: Rename dw_pcie_rp::has_msi_ctrl to dw_pcie_rp::use_imsi_rx for clarity
  PCI: dwc: Fix grammar and formatting for comment in dw_pcie_remove_ext_capability()
  PCI: dwc: Use multiple iATU windows for mapping large bridge windows and DMA ranges
  PCI: dwc: Remove duplicate dw_pcie_ep_hide_ext_capability() function
  PCI: dwc: Skip waiting for L2/L3 Ready if dw_pcie_rp::skip_l23_wait is true
  PCI: dwc: Fail dw_pcie_host_init() if dw_pcie_wait_for_link() returns -ETIMEDOUT
  PCI: dwc: Rework the error print of dw_pcie_wait_for_link()
  PCI: dwc: Rename and move ltssm_status_string() to pcie-designware.c
  PCI: dwc: Return -EIO from dw_pcie_wait_for_link() if device is not active
  PCI: dwc: Return -ENODEV from dw_pcie_wait_for_link() if device is not found
  PCI: dwc: Use cfg0_base as iMSI-RX target address to support 32-bit MSI devices
  PCI: dwc: ep: Cache MSI outbound iATU mapping
  Revert "PCI: dwc: Don't wait for link up if driver can detect Link Up event"
  Revert "PCI: qcom: Enumerate endpoints based on Link up event in 'global_irq' interrupt"
  Revert "PCI: qcom: Enable MSI interrupts together with Link up if 'Global IRQ' is supported"
  Revert "PCI: qcom: Don't wait for link if we can detect Link Up"
  Revert "PCI: dw-rockchip: Enumerate endpoints based on dll_link_up IRQ"
  Revert "PCI: dw-rockchip: Don't wait for link since we can detect Link Up"
  PCI: dwc: Skip PME_Turn_Off broadcast and L2/L3 transition during suspend if link is not up
  PCI: dw-rockchip: Change get_ltssm() to provide L1 Substates info
  PCI: dwc: Add L1 Substates context to ltssm_status of debugfs
  PCI: qcom: Remove DPC Extended Capability
  PCI: qcom: Remove MSI-X Capability for Root Ports
  PCI: dwc: Remove MSI/MSIX capability for Root Port if iMSI-RX is used as MSI controller
  PCI: dwc: Add new APIs to remove standard and extended Capability
  PCI: Add preceding capability position support in PCI_FIND_NEXT_*_CAP macros
2026-02-06 17:09:34 -06:00
arch Misc fixes: 2025-12-14 06:10:35 +12:00
block block-6.19-20251211 2025-12-12 22:04:18 +12:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto Networking changes for 6.19. 2025-12-03 17:24:33 -08:00
Documentation Merge branch 'pci/controller/dwc' 2026-02-06 17:09:34 -06:00
drivers Merge branch 'pci/controller/dwc' 2026-02-06 17:09:34 -06:00
fs We have a patch that adds an initial set of tracepoints to the MDS 2025-12-14 15:24:10 +12:00
include Merge branch 'pci/controller/dwc' 2026-02-06 17:09:34 -06:00
init Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
io_uring io_uring-6.19-20251211 2025-12-12 22:01:32 +12:00
ipc Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
kernel resource: Increase MAX_IORES_LEVEL to 8 2026-01-27 16:36:51 -06:00
lib Miscellaneous fixes: 2025-12-14 06:04:16 +12:00
LICENSES LICENSES: Add modern form of the LGPL-2.1 tags to the usage guide section 2025-10-22 07:58:19 +02:00
mm There are no significant series in this small merge. Please see the 2025-12-13 20:55:12 +12:00
net We have a patch that adds an initial set of tracepoints to the MDS 2025-12-14 15:24:10 +12:00
rust USB/Thunderbolt changes for 6.19-rc1 2025-12-06 18:42:12 -08:00
samples USB/Thunderbolt changes for 6.19-rc1 2025-12-06 18:42:12 -08:00
scripts There are no significant series in this small merge. Please see the 2025-12-13 20:55:12 +12:00
security Trivial optimization. 2025-12-14 15:21:02 +12:00
sound soundwire updates for 6.19 2025-12-13 16:26:55 +12:00
tools selftests: pci_endpoint: Add BAR subrange mapping test case 2026-01-29 17:42:37 -06:00
usr initramfs: add gen_init_cpio to hostprogs unconditionally 2025-11-26 21:55:40 +01:00
virt soc: driver updates for 6.19 2025-12-05 17:29:04 -08:00
.clang-format Significant patch series in this merge are as follows: 2025-12-05 13:52:43 -08:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: remove Alyssa Rosenzweig 2025-09-18 21:17:31 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore rust: kbuild: add proc macro library support 2025-11-24 17:15:36 +01:00
.mailmap Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
.pylintrc docs: Move the python libraries to tools/lib/python 2025-11-18 09:22:40 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS phy-for-6.19 2025-12-09 06:31:47 +09:00
Kbuild sched: Make migrate_{en,dis}able() inline 2025-09-25 09:57:16 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS MAINTAINERS: Add ASPEED PCIe RC driver 2025-12-23 21:27:00 +05:30
Makefile Linux 6.19-rc1 2025-12-14 16:05:07 +12:00
README README: restructure with role-based documentation and guidelines 2025-11-29 08:40:33 -07:00

Linux kernel
============

The Linux kernel is the core of any Linux operating system. It manages hardware,
system resources, and provides the fundamental services for all other software.

Quick Start
-----------

* Report a bug: See Documentation/admin-guide/reporting-issues.rst
* Get the latest kernel: https://kernel.org
* Build the kernel: See Documentation/admin-guide/quickly-build-trimmed-linux.rst
* Join the community: https://lore.kernel.org/

Essential Documentation
-----------------------

All users should be familiar with:

* Building requirements: Documentation/process/changes.rst
* Code of Conduct: Documentation/process/code-of-conduct.rst
* License: See COPYING

Documentation can be built with make htmldocs or viewed online at:
https://www.kernel.org/doc/html/latest/


Who Are You?
============

Find your role below:

* New Kernel Developer - Getting started with kernel development
* Academic Researcher - Studying kernel internals and architecture
* Security Expert - Hardening and vulnerability analysis
* Backport/Maintenance Engineer - Maintaining stable kernels
* System Administrator - Configuring and troubleshooting
* Maintainer - Leading subsystems and reviewing patches
* Hardware Vendor - Writing drivers for new hardware
* Distribution Maintainer - Packaging kernels for distros


For Specific Users
==================

New Kernel Developer
--------------------

Welcome! Start your kernel development journey here:

* Getting Started: Documentation/process/development-process.rst
* Your First Patch: Documentation/process/submitting-patches.rst
* Coding Style: Documentation/process/coding-style.rst
* Build System: Documentation/kbuild/index.rst
* Development Tools: Documentation/dev-tools/index.rst
* Kernel Hacking Guide: Documentation/kernel-hacking/hacking.rst
* Core APIs: Documentation/core-api/index.rst

Academic Researcher
-------------------

Explore the kernel's architecture and internals:

* Researcher Guidelines: Documentation/process/researcher-guidelines.rst
* Memory Management: Documentation/mm/index.rst
* Scheduler: Documentation/scheduler/index.rst
* Networking Stack: Documentation/networking/index.rst
* Filesystems: Documentation/filesystems/index.rst
* RCU (Read-Copy Update): Documentation/RCU/index.rst
* Locking Primitives: Documentation/locking/index.rst
* Power Management: Documentation/power/index.rst

Security Expert
---------------

Security documentation and hardening guides:

* Security Documentation: Documentation/security/index.rst
* LSM Development: Documentation/security/lsm-development.rst
* Self Protection: Documentation/security/self-protection.rst
* Reporting Vulnerabilities: Documentation/process/security-bugs.rst
* CVE Procedures: Documentation/process/cve.rst
* Embargoed Hardware Issues: Documentation/process/embargoed-hardware-issues.rst
* Security Features: Documentation/userspace-api/seccomp_filter.rst

Backport/Maintenance Engineer
-----------------------------

Maintain and stabilize kernel versions:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* Backporting Guide: Documentation/process/backporting.rst
* Applying Patches: Documentation/process/applying-patches.rst
* Subsystem Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git for Maintainers: Documentation/maintainer/configure-git.rst

System Administrator
--------------------

Configure, tune, and troubleshoot Linux systems:

* Admin Guide: Documentation/admin-guide/index.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Sysctl Tuning: Documentation/admin-guide/sysctl/index.rst
* Tracing/Debugging: Documentation/trace/index.rst
* Performance Security: Documentation/admin-guide/perf-security.rst
* Hardware Monitoring: Documentation/hwmon/index.rst

Maintainer
----------

Lead kernel subsystems and manage contributions:

* Maintainer Handbook: Documentation/maintainer/index.rst
* Pull Requests: Documentation/maintainer/pull-requests.rst
* Managing Patches: Documentation/maintainer/modifying-patches.rst
* Rebasing and Merging: Documentation/maintainer/rebasing-and-merging.rst
* Development Process: Documentation/process/maintainer-handbooks.rst
* Maintainer Entry Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git Configuration: Documentation/maintainer/configure-git.rst

Hardware Vendor
---------------

Write drivers and support new hardware:

* Driver API Guide: Documentation/driver-api/index.rst
* Driver Model: Documentation/driver-api/driver-model/driver.rst
* Device Drivers: Documentation/driver-api/infrastructure.rst
* Bus Types: Documentation/driver-api/driver-model/bus.rst
* Device Tree Bindings: Documentation/devicetree/bindings/
* Power Management: Documentation/driver-api/pm/index.rst
* DMA API: Documentation/core-api/dma-api.rst

Distribution Maintainer
-----------------------

Package and distribute the kernel:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* ABI Documentation: Documentation/ABI/README
* Kernel Configuration: Documentation/kbuild/kconfig.rst
* Module Signing: Documentation/admin-guide/module-signing.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Tainted Kernels: Documentation/admin-guide/tainted-kernels.rst



Communication and Support
=========================

* Mailing Lists: https://lore.kernel.org/
* IRC: #kernelnewbies on irc.oftc.net
* Bugzilla: https://bugzilla.kernel.org/
* MAINTAINERS file: Lists subsystem maintainers and mailing lists
* Email Clients: Documentation/process/email-clients.rst