I am looking in amdgpu_top and see the following:
Throttle Status: [PROCHOT_CPU, PROCHOT_GPU]
Using a EC CCD, there is a “apthrottle” command that lists the status of each prochot throttle.
The EC apthrottle command says there are no active PROCHOT throttles, but amdgpu_top says there are.
So, the purpose of this message is to try to fix the PROCHOT behavior so that it actually sets and clears the PROCHOT correctly.
The EC attempts to set and clear them by writing to a GPIO on the EC.
Do anyone know how these throttles are done.
Are they level controlled, or toggled or what?
As it stands, the EC source code thinks sending a 0 to the GPIO activates the PROCHOT, and sending a 1 to the GPIO de-activates it.
Is that correct?
If I recall, this is a driver bug - not an “actual” issue. It was reported in the LACT github as well.
I get it on AMDGPU_TOP as well:
I also get it on LACT:
But, at 34 degrees, and a fresh paste job on the GPU, I dont think im actually throttling 
Here is the upstream bug:
seems to affect 7000 series cards.
I realized after all this you are looking at a slightly diff issue though…
I did some testing, and manually set and reset the PROCHOT GPIO that the EC can set.
I found that it appears in amdgpu_top as Throttle Status: [EDC_CPU]
When set, it clocks everything really slow 450Mhz and uses less than 10W.
So, by doing that, I have found that the EC has no control of the PROCHOT_CPU and PROCHOT_GPU.
I will have to look elsewhere to fix those. Any clues?
Way over my head
@Mario_Limonciello is this in your wheelhouse at all?
There is a timing criteria with how long EC asserts PROCHOT for. By manually toggling it you might be breaking the timing requirements.
I have found some more information out about this now.
The EC uses the sb_rmi_mailbox_xfer() to set the PMF power profile.
This is set depending on:
The amount of power the PSU has.
Whether it is a SPR or EPR PSU.
Whether charger in “bypass” or not.
The power profile selected by the user.
A PMF looks like this:
PMF: SPL 45000mW, sPPT 54000mW, fPPT 60000mW, p3T 118000mW, ao_sppt 60000mW
So, when you see amdgpu_top Throttle Status saying SPPT, it means it is applying the SPPT limit.
So, if people are not getting the power they expect, it might mean that the EC has selected the wrong PMF profile.
