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diff --git a/Documentation/acpi/linuxized-acpica.txt b/Documentation/acpi/linuxized-acpica.txt deleted file mode 100644 index 3ad7b0dfb083..000000000000 --- a/Documentation/acpi/linuxized-acpica.txt +++ /dev/null @@ -1,262 +0,0 @@ -Linuxized ACPICA - Introduction to ACPICA Release Automation - -Copyright (C) 2013-2016, Intel Corporation -Author: Lv Zheng <lv.zheng@intel.com> - - -Abstract: - -This document describes the ACPICA project and the relationship between -ACPICA and Linux. It also describes how ACPICA code in drivers/acpi/acpica, -include/acpi and tools/power/acpi is automatically updated to follow the -upstream. - - -1. ACPICA Project - - The ACPI Component Architecture (ACPICA) project provides an operating - system (OS)-independent reference implementation of the Advanced - Configuration and Power Interface Specification (ACPI). It has been - adapted by various host OSes. By directly integrating ACPICA, Linux can - also benefit from the application experiences of ACPICA from other host - OSes. - - The homepage of ACPICA project is: www.acpica.org, it is maintained and - supported by Intel Corporation. - - The following figure depicts the Linux ACPI subsystem where the ACPICA - adaptation is included: - - +---------------------------------------------------------+ - | | - | +---------------------------------------------------+ | - | | +------------------+ | | - | | | Table Management | | | - | | +------------------+ | | - | | +----------------------+ | | - | | | Namespace Management | | | - | | +----------------------+ | | - | | +------------------+ ACPICA Components | | - | | | Event Management | | | - | | +------------------+ | | - | | +---------------------+ | | - | | | Resource Management | | | - | | +---------------------+ | | - | | +---------------------+ | | - | | | Hardware Management | | | - | | +---------------------+ | | - | +---------------------------------------------------+ | | - | | | +------------------+ | | | - | | | | OS Service Layer | | | | - | | | +------------------+ | | | - | | +-------------------------------------------------|-+ | - | | +--------------------+ | | - | | | Device Enumeration | | | - | | +--------------------+ | | - | | +------------------+ | | - | | | Power Management | | | - | | +------------------+ Linux/ACPI Components | | - | | +--------------------+ | | - | | | Thermal Management | | | - | | +--------------------+ | | - | | +--------------------------+ | | - | | | Drivers for ACPI Devices | | | - | | +--------------------------+ | | - | | +--------+ | | - | | | ...... | | | - | | +--------+ | | - | +---------------------------------------------------+ | - | | - +---------------------------------------------------------+ - - Figure 1. Linux ACPI Software Components - - NOTE: - A. OS Service Layer - Provided by Linux to offer OS dependent - implementation of the predefined ACPICA interfaces (acpi_os_*). - include/acpi/acpiosxf.h - drivers/acpi/osl.c - include/acpi/platform - include/asm/acenv.h - B. ACPICA Functionality - Released from ACPICA code base to offer - OS independent implementation of the ACPICA interfaces (acpi_*). - drivers/acpi/acpica - include/acpi/ac*.h - tools/power/acpi - C. Linux/ACPI Functionality - Providing Linux specific ACPI - functionality to the other Linux kernel subsystems and user space - programs. - drivers/acpi - include/linux/acpi.h - include/linux/acpi*.h - include/acpi - tools/power/acpi - D. Architecture Specific ACPICA/ACPI Functionalities - Provided by the - ACPI subsystem to offer architecture specific implementation of the - ACPI interfaces. They are Linux specific components and are out of - the scope of this document. - include/asm/acpi.h - include/asm/acpi*.h - arch/*/acpi - -2. ACPICA Release - - The ACPICA project maintains its code base at the following repository URL: - https://github.com/acpica/acpica.git. As a rule, a release is made every - month. - - As the coding style adopted by the ACPICA project is not acceptable by - Linux, there is a release process to convert the ACPICA git commits into - Linux patches. The patches generated by this process are referred to as - "linuxized ACPICA patches". The release process is carried out on a local - copy the ACPICA git repository. Each commit in the monthly release is - converted into a linuxized ACPICA patch. Together, they form the monthly - ACPICA release patchset for the Linux ACPI community. This process is - illustrated in the following figure: - - +-----------------------------+ - | acpica / master (-) commits | - +-----------------------------+ - /|\ | - | \|/ - | /---------------------\ +----------------------+ - | < Linuxize repo Utility >-->| old linuxized acpica |--+ - | \---------------------/ +----------------------+ | - | | - /---------\ | - < git reset > \ - \---------/ \ - /|\ /+-+ - | / | - +-----------------------------+ | | - | acpica / master (+) commits | | | - +-----------------------------+ | | - | | | - \|/ | | - /-----------------------\ +----------------------+ | | - < Linuxize repo Utilities >-->| new linuxized acpica |--+ | - \-----------------------/ +----------------------+ | - \|/ - +--------------------------+ /----------------------\ - | Linuxized ACPICA Patches |<----------------< Linuxize patch Utility > - +--------------------------+ \----------------------/ - | - \|/ - /---------------------------\ - < Linux ACPI Community Review > - \---------------------------/ - | - \|/ - +-----------------------+ /------------------\ +----------------+ - | linux-pm / linux-next |-->< Linux Merge Window >-->| linux / master | - +-----------------------+ \------------------/ +----------------+ - - Figure 2. ACPICA -> Linux Upstream Process - - NOTE: - A. Linuxize Utilities - Provided by the ACPICA repository, including a - utility located in source/tools/acpisrc folder and a number of - scripts located in generate/linux folder. - B. acpica / master - "master" branch of the git repository at - <https://github.com/acpica/acpica.git>. - C. linux-pm / linux-next - "linux-next" branch of the git repository at - <http://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git>. - D. linux / master - "master" branch of the git repository at - <http://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git>. - - Before the linuxized ACPICA patches are sent to the Linux ACPI community - for review, there is a quality assurance build test process to reduce - porting issues. Currently this build process only takes care of the - following kernel configuration options: - CONFIG_ACPI/CONFIG_ACPI_DEBUG/CONFIG_ACPI_DEBUGGER - -3. ACPICA Divergences - - Ideally, all of the ACPICA commits should be converted into Linux patches - automatically without manual modifications, the "linux / master" tree should - contain the ACPICA code that exactly corresponds to the ACPICA code - contained in "new linuxized acpica" tree and it should be possible to run - the release process fully automatically. - - As a matter of fact, however, there are source code differences between - the ACPICA code in Linux and the upstream ACPICA code, referred to as - "ACPICA Divergences". - - The various sources of ACPICA divergences include: - 1. Legacy divergences - Before the current ACPICA release process was - established, there already had been divergences between Linux and - ACPICA. Over the past several years those divergences have been greatly - reduced, but there still are several ones and it takes time to figure - out the underlying reasons for their existence. - 2. Manual modifications - Any manual modification (eg. coding style fixes) - made directly in the Linux sources obviously hurts the ACPICA release - automation. Thus it is recommended to fix such issues in the ACPICA - upstream source code and generate the linuxized fix using the ACPICA - release utilities (please refer to Section 4 below for the details). - 3. Linux specific features - Sometimes it's impossible to use the - current ACPICA APIs to implement features required by the Linux kernel, - so Linux developers occasionally have to change ACPICA code directly. - Those changes may not be acceptable by ACPICA upstream and in such cases - they are left as committed ACPICA divergences unless the ACPICA side can - implement new mechanisms as replacements for them. - 4. ACPICA release fixups - ACPICA only tests commits using a set of the - user space simulation utilities, thus the linuxized ACPICA patches may - break the Linux kernel, leaving us build/boot failures. In order to - avoid breaking Linux bisection, fixes are applied directly to the - linuxized ACPICA patches during the release process. When the release - fixups are backported to the upstream ACPICA sources, they must follow - the upstream ACPICA rules and so further modifications may appear. - That may result in the appearance of new divergences. - 5. Fast tracking of ACPICA commits - Some ACPICA commits are regression - fixes or stable-candidate material, so they are applied in advance with - respect to the ACPICA release process. If such commits are reverted or - rebased on the ACPICA side in order to offer better solutions, new ACPICA - divergences are generated. - -4. ACPICA Development - - This paragraph guides Linux developers to use the ACPICA upstream release - utilities to obtain Linux patches corresponding to upstream ACPICA commits - before they become available from the ACPICA release process. - - 1. Cherry-pick an ACPICA commit - - First you need to git clone the ACPICA repository and the ACPICA change - you want to cherry pick must be committed into the local repository. - - Then the gen-patch.sh command can help to cherry-pick an ACPICA commit - from the ACPICA local repository: - - $ git clone https://github.com/acpica/acpica - $ cd acpica - $ generate/linux/gen-patch.sh -u [commit ID] - - Here the commit ID is the ACPICA local repository commit ID you want to - cherry pick. It can be omitted if the commit is "HEAD". - - 2. Cherry-pick recent ACPICA commits - - Sometimes you need to rebase your code on top of the most recent ACPICA - changes that haven't been applied to Linux yet. - - You can generate the ACPICA release series yourself and rebase your code on - top of the generated ACPICA release patches: - - $ git clone https://github.com/acpica/acpica - $ cd acpica - $ generate/linux/make-patches.sh -u [commit ID] - - The commit ID should be the last ACPICA commit accepted by Linux. Usually, - it is the commit modifying ACPI_CA_VERSION. It can be found by executing - "git blame source/include/acpixf.h" and referencing the line that contains - "ACPI_CA_VERSION". - - 3. Inspect the current divergences - - If you have local copies of both Linux and upstream ACPICA, you can generate - a diff file indicating the state of the current divergences: - - # git clone https://github.com/acpica/acpica - # git clone http://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git - # cd acpica - # generate/linux/divergences.sh -s ../linux |