Check the Read QoS, Write QoS, Read Commands Issuing Capability, and Write Commands Issuing Capability configuration of HP ports that interface the VCU with the PS DDR.
Note: For VCU traffic, the QoS should be set as Best Effort (BE) and outstanding
transaction count for read/write commands should be set to maximum, which is
0xF
for all AXI HP ports.The AXI-QoS{3:0] lines behavior define three types of following Traffic in Decimal format on the AXI Bus.
Traffic Class | Read QoS Value | Write QoS Value |
---|---|---|
Best Effort (BE) | 0-3 | 0-7 |
Video (V) | 4-11 | 8-15 |
Low Latency (LL) | 12-15 | N/A |
Following is the reference QoS configuration script as per VCU recommendation.
#!/bin/bash
/sbin/devmem 0xfd380008 w 0x3 -> RDQoS for S_AXI_HP0_FPD
/sbin/devmem 0xfd390008 w 0x3 -> RDQoS for S_AXI_HP1_FPD
/sbin/devmem 0xfd3a0008 w 0x3 -> RDQoS for S_AXI_HP2_FPD
/sbin/devmem 0xfd3b0008 w 0x3 -> RDQoS for S_AXI_HP3_FPD
/sbin/devmem 0xfd38001c w 0x3 -> WRQoS for S_AXI_HP0_FPD
/sbin/devmem 0xfd39001c w 0x3 -> WRQoS for S_AXI_HP1_FPD
/sbin/devmem 0xfd3a001c w 0x3 -> WRQoS for S_AXI_HP2_FPD
/sbin/devmem 0xfd3b001c w 0x3 -> WRQoS for S_AXI_HP3_FPD
/sbin/devmem 0xfd380004 w 0xF -> RDISSUE for S_AXI_HP0_FPD
/sbin/devmem 0xfd390004 w 0xF -> RDISSUE for S_AXI_HP1_FPD
/sbin/devmem 0xfd3A0004 w 0xF -> RDISSUE for S_AXI_HP2_FPD
/sbin/devmem 0xfd3B0004 w 0xF -> RDISSUE for S_AXI_HP3_FPD
/sbin/devmem 0xfd380018 w 0xF -> WRISSUE for S_AXI_HP0_FPD
/sbin/devmem 0xfd390018 w 0xF -> WRISSUE for S_AXI_HP1_FPD
/sbin/devmem 0xfd3A0018 w 0xF -> WRISSUE for S_AXI_HP2_FPD
/sbin/devmem 0xfd3B0018 w 0xF -> WRISSUE for S_AXI_HP3_FPD