Re: USB-C DisplayPort display failing to stay active with Intel Barlow Ridge USB4 controller, power-management related issue?

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, 11 Nov 2024 10:22:23 +0200
Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> wrote:

> Hi,
> 
> On Thu, Nov 07, 2024 at 11:45:44AM +0200, Mika Westerberg wrote:
> > Hi,
> > 
> > On Wed, Nov 06, 2024 at 11:01:34AM -0600, Aaron Rainbolt wrote:  
> > > > Unfortunately that does not help here. I need to figure
> > > > something else how to detect the redrive case with this
> > > > firmware but first, does this work in Windows? I mean if you
> > > > install Windows to this same system does it work as expected?  
> > > 
> > > It does work as expected under Windows 11, with one major caveat.
> > > We used a Windows 11 ISO with a setup.exe created on April 05
> > > 2023 for installing the test system, and after initial
> > > installation it behaved exactly the same way as Linux behaves now
> > > (displays going blank soon after being plugged in). However,
> > > after installing all available Windows updates, the issue
> > > resolved, and the displays worked exactly as intended (the
> > > screens are recognized when attached and do not end up
> > > disconnecting after a timeout).
> > > 
> > > Would it be helpful to test on Windows 11, and provide a report
> > > and system logs?  
> > 
> > Unfortunately, I don't know anything about Windows ;-)
> > 
> > However, I asked our Thunderbolt hardware/firmware team about this,
> > if they have any idea how it was solved in Windows side. Might take
> > a couple of days though.  
> 
> While waiting for this, I wonder if you guys could do one more
> experiment? I would like to get the traces what is happening there
> (hoping something pops out there). Following steps:
> 
>   1. Download and install tbtools [1].
>   2. Build and install the kernel with my "redrive" patch.
>   3. Boot the system up, nothing connected.
>   4. Wait until the Barlow Ridge is in runtime suspend (so wait for
>      ~30s or so)
>   5. Enable tracing:
> 
>     # tbtrace enable
> 
>   6. Plug in USB-C monitor to the USB-C port of the Barlow Ridge. Do
> not run 'lspci -k'. Expectation here is that there is no picture on
>      the monitor (in other words the issue reproduces).
> 
>   7. Stop tracing and take full dump:
> 
>     # tbtrace disable
>     # tbtrace dump -vv > trace.out
> 
>   8. Send trace.out along with full dmesg to me.
> 
> Thanks!
> 
> [1] https://github.com/intel/tbtools

Testing done as requested. Notes from tester:



* I verified lsmod |grep thunderbolt which showed module.
* When running sudo ./tbtrace enable, output was Thunderbolt/USB4
  tracing: Enabled.
* When plugging in monitor, it wakes the backlight, but there is no
  image. syslog shows it as LG monitor controls. The monitor reports
  "no signal" and eventually turns off the backlight to save power.
* When running sudo ./tbtrace disable, output was Thunderbolt/USB4
  tracing: Disabled.
* Output was save using tbtrace dump -vv > trace.out and sudo dmesg >
  trace.dmesg. trace.out is an empty file.

---

(Yes, that's correct, trace.out is empty. I attached it nonetheless,
but it's a 0-byte file. I'm guessing the Thunderbolt chip probably
didn't come out of suspend?)

Attachment: trace.dmesg
Description: Binary data

Attachment: trace.out
Description: Binary data


[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux