Visible to Intel only — GUID: kvr1673393480930
Ixiasoft
Visible to Intel only — GUID: kvr1673393480930
Ixiasoft
5.1.6.3.1. Descriptor Structure
- Transmit descriptor ring length register (DMA_CH(#i)_Tx_Control2)
- Receive descriptor ring length register (DMA_CH(#i)_Rx_Control2)
- Current descriptor pointer = descriptor tail pointer
The DMA goes into the suspend mode when this condition occurs. The application must perform a write to the descriptor tail pointer register and increase the offset so that the following condition is true:
- Current descriptor < pointer descriptor tail pointer
For descriptors owned by the application, the OWN bit of TDES3 and RDES3 fields are reset to 0. For descriptors owned by the DMA, the OWN bit is set to 1. If the application has only two descriptors in the beginning, the application sets the last descriptor address (tail pointer) to descriptor base address + 1. The DMA processes the first descriptor and then waits for the application to advance and change the tail pointer back to the descriptor base address.