DRA821U: Booting and authenticating qnx-ifs from SD card leads to "SERDES PLL is not locked" on XJ72005BALM

Hi Experts,

We have developed the full authentication feature/secure-boot on 5ALM, and it works fine when booting both from SD and eMMC.

The secure-boot also works file when booting signed qnx-ifs on 5BALM from eMMC.

But it will cause "SERDES PLL is not locked" when booting signed qnx-ifs from SD card as following:

CpswMacPort_setSgmiiInterface: MAC 1: SERDES PLL is not locked
CpswMacPort_setSgmiiInterface: MAC 1: Failed to set SGMII interface: -9

Boot speed reference:

-----------------------------------------------

Boot from eMMC:

k3_r5f_rproc r5f@41000000: Core 1 is already in use. No rproc commands work
k3_r5f_rproc r5f@41400000: Core 2 is already in use. No rproc commands work
6914376 bytes read in 44 ms (149.9 MiB/s)
Load Remote Processor 2 with data@addr=0x82000000 6914376 bytes: Success!
4884844 bytes read in 34 ms (137 MiB/s)
Load Remote Processor 3 with data@addr=0x82000000 4884844 bytes: Success!
8075517 bytes read in 64 ms (120.3 MiB/s)
Authentication passed
## Starting application at 0x80080000 ...

-----------------------------------------------

Boot from SD:

k3_r5f_rproc r5f@41000000: Core 1 is already in use. No rproc commands work
k3_r5f_rproc r5f@41400000: Core 2 is already in use. No rproc commands work
6914376 bytes read in 289 ms (22.8 MiB/s)
Load Remote Processor 2 with data@addr=0x82000000 6914376 bytes: Success!
4884844 bytes read in 205 ms (22.7 MiB/s)
Load Remote Processor 3 with data@addr=0x82000000 4884844 bytes: Success!
8077581 bytes read in 339 ms (22.7 MiB/s)
Authentication passed
## Starting application at 0x80080000 ...

-----------------------------------------------

What's wrong with this SoC/XJ72005BALM? We can't do any network related tests/operations unless qnx-ifs is burned into eMMC, so it slows down our development process. How to fix it? 

Thanks,

Jianqiang