Visible to Intel only — GUID: vdm1743465878880
Ixiasoft
Visible to Intel only — GUID: vdm1743465878880
Ixiasoft
2.2.7. LPDDR5 and DDR5 reduced sequential write/read bandwidth when using Fabric Sync Fabric direct mode in x16 2-channel configuration
Description
In LPDDR5 and DDR5 memory interfaces, when using x16 2-channel configuration for long burst sequential access during write or read operations, in fabric sync access mode, performance is limited to 50% per read/write sub-channel.
- LPDDR5 x16 1-channel when placed in the bottom GPIO-B sub-bank
- DDR5 x16 1-channel
- All impacted configurations, listed below, with random access and in sequential access with mixed read-write traffic
- In all supported configurations with NoC access mode
Impacted configurations:
- DDR5 x32 configuration in DIMM or component configuration
- LPDDR5 x32 configuration
- LPDDR5 and DDR5 x16 2-channel configuration only with Fabric Sync
- LPDDR5 x32 1-channel
- LPDDR5 x16 1-channel when placed in the top GPIO-B sub-bank
Workaround
We recommend using the Fabric Async mode for the impacted configurations. You can access via NoC or Fabric Async mode with the user clock set to ¼ of the memory clock which provides full sequential bandwidth on a single sub-channel.
Status
Devices Affected | Planned Fix |
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None |