ACPI（高级配置和电源接口）和 ACPICA（ACPI 组件架构）密切相关，但在系统电源管理和配置方面却有不同的作用。以下是它们的区别：
ACPI（高级配置和电源接口）
- 定义： ACPI 是由英特尔（Intel）、微软（Microsoft）和东芝（Toshiba）共同开发的开放式行业标准，用于管理计算机和操作系统的电源管理和硬件配置。
- 目的：ACPI 为操作系统提供了一种控制设备电源使用的方法（如关闭未使用的设备、控制 CPU 状态等）。它定义了允许操作系统与系统固件通信的接口，以有效管理资源和电源。
- 组件： ACPI 由定义电源管理状态（如睡眠、休眠）、热管理和系统资源管理的规范组成。
- 使用方法： 它由系统固件（BIOS 或 UEFI）实现，直接与操作系统交互，提供动态电源控制。
ACPICA（ACPI 组件架构）
- 定义：ACPICA ACPICA 是英特尔发起的一个项目，提供 ACPI 规范的实现。它由一套开源的实用程序和库组成，便于操作系统使用 ACPI。
- 目的：ACPICA 作为一个框架，可帮助操作系统供应商更轻松地实现 ACPI 功能。它抽象了处理 ACPI 操作所涉及的一些复杂问题，并提供了标准化组件。
- 组件： ACPICA 包括 ACPI 解释器、AML（ACPI 机器语言）解析器以及用于调试和测试 ACPI 表的工具。
- 使用方法： Linux、BSD 等操作系统使用 ACPICA 与基于 ACPI 的硬件交互。操作系统供应商可以使用 ACPICA 来确保与 ACPI 规范的兼容性，而不是从头开始创建自己的 ACPI 实现。
差异总结：
- ACPI 是定义如何管理电源和系统配置的规范。
- ACPICA 是 ACPI 规范的实现，可帮助操作系统供应商在其系统中支持 ACPI。
简而言之，ACPI 是标准，而 ACPICA 是用于在操作系统中实施该标准的工具包。
ACPI (Advanced Configuration and Power Interface) and ACPICA (ACPI Component Architecture) are closely related but serve different purposes in the context of system power management and configuration. Here’s how they differ:
ACPI (Advanced Configuration and Power Interface)
- Definition: ACPI is an open industry standard developed by Intel, Microsoft, and Toshiba that governs power management and hardware configuration for computers and operating systems.
- Purpose: ACPI provides a way for the operating system to control power usage in devices (such as turning off unused devices, controlling CPU states, etc.). It defines interfaces that allow the OS to communicate with the firmware of a system to manage resources and power efficiently.
- Components: ACPI consists of specifications that define power management states (like sleep, hibernation), thermal management, and system resource management.
- Usage: It is implemented by the system firmware (BIOS or UEFI) and directly interacts with the OS to provide dynamic power control.
ACPICA (ACPI Component Architecture)
- Definition: ACPICA is a project initiated by Intel that provides an implementation of the ACPI specification. It consists of an open-source set of utilities and libraries that facilitate the OS's use of ACPI.
- Purpose: ACPICA serves as a framework that helps OS vendors implement ACPI features more easily. It abstracts some of the complexities involved in handling ACPI operations and provides standardized components.
- Components: ACPICA includes the ACPI interpreter, AML (ACPI Machine Language) parser, and tools for debugging and testing ACPI tables.
- Usage: Operating systems, such as Linux, BSD, and others, use ACPICA to interact with ACPI-based hardware. Instead of creating their own ACPI implementation from scratch, OS vendors can use ACPICA to ensure compatibility with the ACPI specification.
Summary of Differences:
- ACPI is the specification that defines how power and system configuration are managed.
- ACPICA is an implementation of the ACPI specification that helps OS vendors support ACPI in their systems.
In short, ACPI is the standard, while ACPICA is the toolkit used to implement the standard in an OS.
ACPICA 介绍
ACPICA（ACPI 组件架构）是英特尔开发的一个开源项目，它提供了 ACPI（高级配置和电源接口）规范的参考实现。其主要目的是帮助操作系统开发人员轻松集成 ACPI 功能，而无需从头开始实施整个 ACPI 标准。
ACPICA (ACPI Component Architecture) is an open-source project developed by Intel that provides a reference implementation of the ACPI (Advanced Configuration and Power Interface) specification. Its primary purpose is to help operating system developers easily incorporate ACPI functionality without needing to implement the entire ACPI standard from scratch.
ACPI 组件架构（ACPICA）是高级配置和电源接口（ACPI）规范的参考实现。该实现将 ACPI 直接集成为内核驻留子系统，无需更改 ACPICA 核心代码，从而简化了复杂的 ACPI 操作系统实现。
ACPI Component Architecture (ACPICA) is a reference implementation of the Advanced Configuration and Power Interface (ACPI) specification. This implementation simplifies complex ACPI operating system implementations by integrating it directly as a kernel-resident subsystem, without changes to the core ACPICA code.
从本质上讲，ACPICA 是一个基础工具包，可简化和规范操作系统与基于 ACPI 的固件的交互方式，从而实现高效的电源管理和系统资源控制。
In essence, ACPICA is a foundational toolkit that simplifies and standardizes how operating systems interact with ACPI-based firmware for efficient power management and system resource control.
Why ACPICA?
ACPICA 代码已相当成熟，并实现了以下功能：
* AML（ACPI 机器语言）解释器
* 表管理器
* 命名空间管理器
* 资源管理器
* 固定和通用事件支持
* ACPI 硬件支持
* 支持 ACPI 5.0 规范
ACPICA code is fairly mature and implements the following:
* An AML (ACPI machine language) interpreter
* A table manager
* A namespace manager
* A resource manager
* Fixed and general purpose event support
* ACPI hardware support
* Support for the ACPI 5.0 specification
How It Works
* ACPICA 为 32 位和 64 位平台定义并实现了一组软件组件。
* 该架构将所有操作系统依赖关系隔离到一个相对较小的翻译或转换层（称为操作系统服务层）。
* 这种隔离使 ACPICA 的大部分代码独立于任何操作系统。
* 新操作系统无需更改 ACPICA 代码本身的源代码。
* ACPICA defines and implements a group of software components for both 32-bit and 64-bit platforms.
* The architecture isolates all operating system dependencies to a relatively small translation or conversion layer (called the OS Services Layer)
* This isolation enables the bulk of the ACPICA code to be independent of any individual operating system.
* Requires no source code changes within the ACPICA code itself for new operating systems.
What's Included
主要内核级组件
* AML 解释器
* ACPI 表管理器
* ACPI 命名空间管理器
* ACPI 资源管理器
* ACPI 固定和通用事件支持
* ACPI 硬件支持
* AML 反汇编器（可选）
* AML 调试器（可选）
Major kernel-level components:
* AML Interpreter
* ACPI Table Manager
* ACPI Namespace Manager
* ACPI Resource Manager
* ACPI Fixed and General Purpose Event Support
* ACPI Hardware Support
* AML Disassembler (optional)
* AML Debugger (optional)
用户空间工具和实用程序
* ACPI 源代码编译器和反汇编器 (iASL)
* ACPI 模拟器/执行器 (AcpiExec)
* 将 ACPI 系统表转储为 ASCII 实用程序/ (acpidump)
* ACPI 表提取器（acpidump 工具的逆向）/ (acpixtract)
* ACPI 帮助实用程序 (AcpiHelp)
注意: ACPICA 组件在内核模式和用户模式下都有运行。
User-space tools and utilities:
* ACPI Source Code Compiler & Disassembler (iASL)
* ACPI Simulator/Executer (AcpiExec)
* ACPI System Table dump to ASCII utility/ (acpidump)
* ACPI Table Extractor (inverse of acpidump utility)/ (acpixtract)
* ACPI Help Utility (AcpiHelp)
Note: The ACPICA components run in both kernel mode and user mode.
System Requirements
* 用 C 语言编写操作系统（或能够与 C 代码接口）。
* 在启动例程中添加 ACPICA 初始化调用。
更多详情，请参阅 ACPI 规范。
* Write operating systems in C (or able to interface to C code).
* Add ACPICA initialization calls into the startup routine.
For more details, see the ACPI specifications.
Environments
ACPICA 采用 ANSI C 语言编写，可在多种不同的 32 位和 64 位操作系统开发环境下生成。源代码包适用于 Microsoft Windows* 和 UNIX*。
* Windows 软件包包括 Visual C++* 项目文件和其他 ACPI 实用程序
* UNIX 软件包的格式和许可适合商业操作系统供应商使用。
没有独立的 Linux* 源代码包，因为针对 Linux 的 ACPICA 更新是以补丁形式定期提供的。ACPICA 子系统经过修改，可与 Linux 内核源代码顺利集成。这包括将 ACPICA 源代码转换为 Linux 内核编码标准，并根据 GNU 通用公共许可证进行授权。
ACPICA is written in ANSI C, and can be generated under many different 32-bit and 64-bit operating system development environments. Source code packages are provided for Microsoft Windows* and UNIX*.
* The Windows package includes Visual C++* project files and other ACPI utilities
* The UNIX package has a format and licensing suitable for inclusion by commercial operating system vendors.
There is no stand-alone Linux* source code package since ACPICA updates for Linux are provided periodically in patch form. The ACPICA subsystem is modified to integrate smoothly with the Linux kernel source. This includes conversion of the ACPICA source code to the Linux kernel coding standard and licensing under the GNU General Public License.
参考：
https://www.intel.com/content/www/us/en/developer/topic-technology/open/acpica/overview.html
