Documentation/driver-api/firmware/introduction.rst
Source file repositories/reference/linux-study-clean/Documentation/driver-api/firmware/introduction.rst
File Facts
- System
- Linux kernel
- Corpus path
Documentation/driver-api/firmware/introduction.rst- Extension
.rst- Size
- 935 bytes
- Lines
- 28
- Domain
- Support Tooling And Documentation
- Bucket
- Documentation
- Inferred role
- Support Tooling And Documentation: documentation
- Status
- atlas-only
Why This File Exists
Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
Dependency Surface
- No C-style include directives detected by the generator.
Detected Declarations
- No top-level syscall, struct, function, initcall, or export declaration detected by the generator.
Annotated Snippet
============
Introduction
============
The firmware API enables kernel code to request files required
for functionality from userspace, the uses vary:
* Microcode for CPU errata
* Device driver firmware, required to be loaded onto device
microcontrollers
* Device driver information data (calibration data, EEPROM overrides),
some of which can be completely optional.
Types of firmware requests
==========================
There are two types of calls:
* Synchronous
* Asynchronous
Which one you use vary depending on your requirements, the rule of thumb
however is you should strive to use the asynchronous APIs unless you also
are already using asynchronous initialization mechanisms which will not
stall or delay boot. Even if loading firmware does not take a lot of time
processing firmware might, and this can still delay boot or initialization,
as such mechanisms such as asynchronous probe can help supplement drivers.Annotation
- Atlas domain: Support Tooling And Documentation / Documentation.
- Implementation status: atlas-only.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.