Documentation/driver-api/cxl/platform/acpi/hmat.rst

Source file repositories/reference/linux-study-clean/Documentation/driver-api/cxl/platform/acpi/hmat.rst

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System: Linux kernel
Corpus path: Documentation/driver-api/cxl/platform/acpi/hmat.rst
Extension: .rst
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Lines: 33
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.

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Annotated Snippet

.. SPDX-License-Identifier: GPL-2.0

===========================================
HMAT - Heterogeneous Memory Attribute Table
===========================================

The Heterogeneous Memory Attributes Table contains information such as cache
attributes and bandwidth and latency details for memory proximity domains.
For the purpose of this document, we will only discuss the SSLIB entry.

SLLBI
=====
The System Locality Latency and Bandwidth Information records latency and
bandwidth information for proximity domains.

This table is used by Linux to configure interleave weights and memory tiers.

Example (Heavily truncated for brevity) ::

               Structure Type : 0001 [SLLBI]
                    Data Type : 00         <- Latency
 Target Proximity Domain List : 00000000
 Target Proximity Domain List : 00000001
                        Entry : 0080       <- DRAM LTC
                        Entry : 0100       <- CXL LTC

               Structure Type : 0001 [SLLBI]
                    Data Type : 03         <- Bandwidth
 Target Proximity Domain List : 00000000
 Target Proximity Domain List : 00000001
                        Entry : 1200       <- DRAM BW
                        Entry : 0200       <- CXL BW

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.