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Renoir - Issue with MCLK/FCLK levels - power_dpm_force_performance_level

Hi,

Brief summary of the problem:

The mclk and fclk frequencies behave strange when changing the performance level on Renoir CPU/APU.

Hardware description:

  • CPU: AMD Ryzen Pro 7 - 4750U
  • GPU: Vega iGPU
  • System Memory: 32 GB
  • Display(s): 2x 1920x1080 144Hz
  • Type of Diplay Connection: DP

System infomration:

  • Distro name and Version: Manjaro Linux
  • Kernel version: 5.8.11 / 5.9.0

How to reproduce the issue:

When changing the power_dpm_force_performance_level the applied frequencies seem to be the opposite of what they should be.

Example:

When performance level is set to "high", it results in the following MCLK/FCLK clockspeeds.

Both are at rather low speed of 800 MHz, SCLK is at highest level of 1.6 GHz though. echo high > /sys/class/drm/card0/device/power_dpm_force_performance_level

power_dpm_force_performance_level:high

pp_dpm_fclk:0: 1333Mhz 
pp_dpm_fclk:1: 1200Mhz 
pp_dpm_fclk:2: 800Mhz *
pp_dpm_fclk:3: 400Mhz 

pp_dpm_mclk:0: 1333Mhz 
pp_dpm_mclk:1: 1200Mhz 
pp_dpm_mclk:2: 800Mhz *
pp_dpm_mclk:3: 400Mhz 

pp_dpm_sclk:0: 200Mhz 
pp_dpm_sclk:1: 700Mhz 
pp_dpm_sclk:2: 1600Mhz *

Switching to "low" performance level results in this: FCLK and MCLK are at 1333 MHz while SCLK is the lowest 200 MHz

power_dpm_force_performance_level:low

pp_dpm_fclk:0: 1333Mhz *
pp_dpm_fclk:1: 1200Mhz 
pp_dpm_fclk:2: 800Mhz 
pp_dpm_fclk:3: 400Mhz 

pp_dpm_mclk:0: 1333Mhz *
pp_dpm_mclk:1: 1200Mhz 
pp_dpm_mclk:2: 800Mhz 
pp_dpm_mclk:3: 400Mhz 

pp_dpm_sclk:0: 200Mhz *
pp_dpm_sclk:1: 700Mhz 
pp_dpm_sclk:2: 1600Mhz

So SCLK clocks are plausible but MCLK/FCLK are the opposite? The order of the levels is reversed. Lowest level 0 for MCLK/FCLK has the highest frequency while it's the other way around for SCLK.

Regards, MO

Edited by Mario Oenning