The prefetch engine interacts between the descriptor fetch engine and C2H DMA write engine to pair up the descriptor and its payload.
| Bit | Bit Width | Field Name | Description |
|---|---|---|---|
| [45] | 1 | valid | Context is valid |
| [44:29] | 16 | sw_crdt | Software credit This field is written by the hardware for internal use. The software must initialize it to 0 and then treat it as read-only. |
| [28] | 1 | pfch | Queue is in prefetch This field is written by the hardware for internal use. The software must initialize it to 0 and then treat it as read-only. |
| [27] | 1 | pfch_en | Enable prefetch |
| [26] | 1 | err | Error detected on this queue During the descriptor per-fetch process, if there are any errors detected, they are logged here. This is per queue basis. |
| [25:8] | 18 | reserved | Reserved |
| [7:5] | 3 | port_id | Port ID |
| [4:1] | 4 | buf_size_idx | Buffer size index |
| [0] | 1 | bypass | C2H bypass mode, set this bit for simple bypass mode. |