imx8mp PCIe compliance test failed

[kei_odagiri]

Hi,

We are undertaking PCIe compliance test for our custom board with i.MX8M Plus. But a couple of test aren't passed yet. I attach a result of the compliance test. It seems the quality of TX signal wave doesn't conform the compliance test. We considered we should correct the drive strength of the signal, and we tried changing some registers in imx8mp, but we couldn't change the amplitude of the signal.

Would you tell us about the register of imx8mp to change the drive strength of PCIe TX signal?

Best regards,

Kei Odagiri

[kei_odagiri]

This topic is too old. So, we can close this ticket.

[Yuri]

@kei_odagiri 
Hello,

   Have You used recommendations of app note AN12444
(PCIe Certification Guide for i.MX8 Series) ?

  In particular, section  2.3 (Test environment).

https://www.nxp.com/docs/en/application-note/AN12444.pdf

Regards,
Yuri.

[kei_odagiri]

Hello,

We have referred to the guide and checked the instruction also section 2.3. I believe it had been done properly. We had accessed the following register, but it didn't work.

Best regards,

Kei Odagiri

[Yuri · Accepted solution]

@kei_odagiri 
Hello,

  Please check if the board follow the Table 8 (PCIe recommendations)
and Table 24 (Trace impedance recommendations) of Hardware Development
Guide for the i.MX8MP.

< https://www.nxp.com/webapp/Download?colCode=IMX8MPHDG >

Regards,
Yuri.

[kei_odagiri]

Sorry, I missed to write this.

Register: CMN_REG065
Fields: 3-0
ANA_AUX_TX_LVL_CTRL

Kei Odagiri