Visible to Intel only — GUID: nik1410905452528
Ixiasoft
Visible to Intel only — GUID: nik1410905452528
Ixiasoft
5.1.7.1. Avalon-ST Descriptor Status Interface
When DMA module completes the processing for one Descriptor Instruction, it returns DMA Status to the Descriptor Controller via the following interfaces.
Signal Name |
Direction |
Description |
---|---|---|
RdAstTxData_o[31:0] |
Output |
Drives status information to the Descriptor Controller component. Refer to DMA Status Bus table below for more information |
RdAstTxValid_o |
Output |
When asserted, indicates that the data is valid. |
Signal Name |
Direction |
Description |
---|---|---|
WrAstTxData_o[31:0] |
Output |
Drives status information to the Descriptor Controller component. Refer to DMA Status Bus table below for more information about this bus. |
WrAstTxValid_o |
Output |
When asserted, indicates that the data is valid. |
Bits |
Name |
Description |
---|---|---|
[31:0] |
Source Low Address | Low-order 32 bits of the DMA source address. The address boundary must align to the 32 bits so that the 2 least significant bits are 2'b00. For the Read DMA module, the source address is the PCIe domain address. For the Write DMA module, the source address is the Avalon-MM domain address. |
[63:32] |
Source High Address | High-order 32 bits of the source address. |
[95:64] |
Destination Low Address | Low-order 32 bits of the DMA destination address. The address boundary must align to the 32 bits so that the 2 least significant bits have the value of 2'b00. For the Read DMA module, the destination address is the Avalon-MM domain address. For the Write DMA module the destination address is the PCIe domain address. |
[127:96] |
Destination High Address | High-order 32 bits of the destination address. |
[145:128] |
DMA Length | Specifies DMA length in dwords. The length must be greater than 0. The maximum length is 1 MB - 4 bytes. |
[153:146] |
DMA Descriptor ID | Specifies up to 128 descriptors. |
[158:154] |
Reserved | — |
[159] | Immediate Write | When set to 1'b1, the Write DMA Engine performs an Immediate Write. The Immediate Write provides a fast mechanism to send a Write TLP upstream. The descriptor stores the 32-bit payload, replacing the Source Low Address field of the descriptor. |