Hi Pavel, On 2/5/24 19:52, Pavel Hofman wrote: > > > Dne 05. 02. 24 v 15:35 Pavel Hofman napsal(a): >> >>> >> It really looks like some DMA performance issue. Stream 980 bytes/ >> 250us (bInterval=2) is bitperfect, no dropped packets. While 24 >> bytes/125us (bInterval=1) gets stuck. IIUC the DMA is not capable of >> copying packets every 125us. Please is there any chance to tweak the >> performance to handle the 125us packets reliably? >> > > I tried increasing f_uac2 req_number/UAC2_DEF_REQ_NUM from 2 to 8 and > streaming seems to run stable at 125us microframes now (in both > directions simultaneously). Please is there any other gadget tweak which > could potentially reduce the risk of dropped packets? Something like > using plain DMA instead of desc DMA (no idea :-) )... > > Thanks a lot for your expert opinion. Yes, it's mandatory to increase f_uac2_req_number, at least 4. Obviously 2 is not enough for descriptor list and main cause of BNA interrupt. Another suggestion to change DMA mode from DDMA to BDMA as I suggested in previous email. Thanks, Minas
