.. 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