Visible to Intel only — GUID: edd1742230212875
Ixiasoft
Visible to Intel only — GUID: edd1742230212875
Ixiasoft
A.1.3.1. Narrow Read Transfer Support
Narrow Read Transfer Support
Narrow read transfer happens when the AXI master generates a read data transfer that is narrower than its data bus width. For example, for a 256-bit AXI data bus, a narrow read transfer happens when ARSIZE is less than 5.
Unaligned Memory Access
Unaligned memory access is not supported on Agilex™ 5 EMIF interfaces. For Fabric EMIF, unaligned memory access is not supported in Fabric Direct Access Mode.
For HPS EMIF, unaligned memory access is not supported on the F2SDRAM Bridge. Unaligned memory access happens when the ARADDR/AWADDR is specified with a value that is not a multiple of the data bus width (in bytes).
The following table shows the AWADDR/ARADDR requirement for aligned memory access in Fabric EMIF and HPS EMIF.
category | AXI Data Width (Bits) | AXI Data Width (Bytes) | AWADDR/ARADDR for Aligned Access |
---|---|---|---|
Fabric EMIF-Direct Access Mode | 256 | 32 | 32n |
HPS EMIF - F2SDRAM | 64 | 8 | 8n |
HPS EMIF - F2SDRAM | 128 | 16 | 16n |
HPS EMIF - F2SDRAM | 256 | 32 | 32n |
Note: n is an integer value equal to or greater than 0.
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You will get a data error if you perform unaligned memory access on the EMIF interfaces.