************************************* DMA Latency Application (dma-latency) ************************************* Xilinx-developed custom tool ``dma-latency`` is used to collect the latency metrics for unidirectional and bidirectional traffic. :: usage: dma-latency [OPTIONS -c (--config) config file that has configuration for IO dma-latency tool takes a configuration file as input. The configuration file format is as below. :: name=mm_1_1 mode=mm #mode dir=bi #dir pf_range=0:0 #no spaces q_range=0:0 #no spaces wb_acc=5 tmr_idx=9 cntr_idx=0 trig_mode=usr_cnt rngidx=9 ram_width=15 #31 bits - 2^31 = 2GB runtime=30 #secs num_threads=8 bidir_en=1 num_pkt=64 pkt_sz=64 **Parameters** - name : name of the configuration - mode : mode of the queue, streaming\(st\) or memory mapped\(mm\). Mode defaults to mm. - dir : Direction of the queue, host-to-card\(h2c\), card-to-host \(c2h\) or both \(bi\). - pf_range : Range of the PFs from 0-3 on which the performance metrics are to be collected. - q_range : Range of the Queues from 0-2047 on which the performance metrics are to be collected. - flags : queue flags - wb_acc : write back accumulation index from CSR register \( 0 - 15 \) - tmr_idx : timer index from CSR register \( 0 - 15 \) - cntr_idx : Counter index from CSR register \( 0 - 15 \) - trig_mode : trigger mode \(every, usr_cnt, usr, usr_tmr, dis\) - rngidx : Ring index from CSR register \( 0 - 15 \) - runtime : Duration of the performance runs, time in seconds. - num_threads : number of threads to be used in dma-perf application to pump the traffic to queues - bidir_en : Enable or Disable the bi-direction mode \( 0: Disable, 1: Enable \) - num_pkt : number of packets - pkt_sz : Packet size