TPS65988: TPS65988 Firmware Setting: TBT Mode Entry

Shin Yung Poo

Part Number: TPS65988

Hi experts,

I implement TPS65988 as PD controller for our project, this PD controller will work with a single port TBT controller (Titan Ridge, TR) where its downstream is USB3.1 Gen 1 and upstream is TBT3.

In this project, I do not want to sink and source any currents to and from the host. So I set it as UFP (as I'm designing a TBT device).

I have encounter a problem where the PD controller does not communicate well with TR and prevent it from entering the TBT mode.

Questions:

1. The below figure is the information I get with USB PD analyzer, and there is a command DiscSVID(NAK), may I know why I get this command?

2. Which registers will take care on TBT mode entry?

Note: I have attached a link to my PD controller firmware setting project file.

drive.google.com/.../view

Thank you.

over 2 years ago

0 Kevin Kosta over 2 years ago

TI__Genius 17975 points

Hi,

Thanks for reaching out on E2E!

I will take a look at this and get back to you soon!

Thank you,

Kevin

0 Zhou Xian Tan over 2 years ago in reply to Kevin Kosta

Prodigy 20 points

Hi Kevin,

Thank you for looking into our post. From our side, we've been trying to tweak some configuration but is still not successful up to know, seeing the same message from PD analyzer. May I know if there is any update from your end?

Any sort of resource, for example if you have a working firmware of the TPS65988 that can be shared to us to explore, will be helpful on our troubleshooting. We would need to successfully bring up the board in another 3 days time, so looking forward to hear from you soon. Thank you!

0 Kevin Kosta over 2 years ago in reply to Zhou Xian Tan

TI__Genius 17975 points

Hi,

I will get back to you on Tuesday as I am out of the office.

Thank you,

Kevin

0 Shin Yung Poo over 2 years ago in reply to Kevin Kosta

Prodigy 20 points

Hi Kevin,

Is there any way that we can change register 0x52 from default 0x500 to 0x503 to enable TBT mode entry?

+1 Kevin Kosta over 2 years ago in reply to Shin Yung Poo

TI__Genius 17975 points

Hi Shin,

Thanks for the follow up!

Are you using the thunderbolt GUI here?

If not can you please request access at https://www.ti.com/product/TPS65982DMC

In the above tool, the intel VID config register 0x52 is exposed for thunderbolt configuration.

Thank you,

Kevin

0 Shin Yung Poo over 2 years ago in reply to Kevin Kosta

Prodigy 20 points

Hi Kevin,

I sent my request, not sure how long it need to take to accept my request. Can you help to speed up the process?

Thank you.

0 Zhou Xian Tan over 2 years ago in reply to Shin Yung Poo

Prodigy 20 points

Hi Kelvin,

Thank you for directing us to the right GUI, but we must ship the system to our customer by this Friday so we have to get the GUI tomorrow to update and validate the system. Both Shin Yung and I have requested the GUI through the link you shared, can you please help to expedite the process so that we can get the GUI tomorrow?

Feel free to let us know if you need further details, thank you.

+1 Kevin Kosta over 2 years ago in reply to Zhou Xian Tan

TI__Genius 17975 points

Hi Zhou and Shin,

Thanks for letting me know about the deadline!

I am working on expediting this and have been in contact with the field team. I will respond back here once approval has been made!

Thank you,

Kevin

0 Kevin Kosta over 2 years ago in reply to Kevin Kosta

TI__Genius 17975 points

Hi Zhou and Shin,

You should have access!

Thank you,

Kevin

0 Kevin Kosta over 2 years ago in reply to Kevin Kosta

TI__Genius 17975 points

Hi Zhou and Shin,

Padraic reached out to me stating that you are facing some issues with the new GUI.

Can you please share your project file with me?

Thank you,

Kevin

0 Shin Yung Poo over 2 years ago in reply to Kevin Kosta

Prodigy 20 points

Hi Kevin,

By using the latest Thunderbolt GUI tool for TPS65988, the PD controller seems never trying to negotiate with DFP and always holds the Titan Ridge in reset.

Before we get the customization tools for TBT, we have try the debug mode and its works well, not sure what causes this issues.

project file for latest GUI:
drive.google.com/.../view

0 Shin Yung Poo over 2 years ago in reply to Shin Yung Poo

Prodigy 20 points

Here I attached the data capture by USB PD analyzer for the firmware set by using TBT GUI tool.

When we programmed with general GUI tool and change data of register 0x52 on the fly with debug mode, we able to enter TBT mode as shown in the figure below.
Firmware for general GUI tool: https://drive.google.com/file/d/1TRuPh_YjNaWKhH1zI9eqLO_5VdRy9Ntk/view?usp=share_link