Bug 106306 - amdgpu CIK power management issues (overdrive and wattman)
Summary: amdgpu CIK power management issues (overdrive and wattman)
Alias: None
Product: DRI
Classification: Unclassified
Component: DRM/AMDgpu (show other bugs)
Version: DRI git
Hardware: x86-64 (AMD64) Linux (All)
: medium normal
Assignee: Default DRI bug account
QA Contact:
Depends on:
Reported: 2018-04-28 22:21 UTC by grmat
Modified: 2019-11-19 08:37 UTC (History)
1 user (show)

See Also:
i915 platform:
i915 features:

dmesg output pp_num_states (3.43 KB, text/plain)
2018-04-28 22:21 UTC, grmat
no flags Details

Description grmat 2018-04-28 22:21:44 UTC
Created attachment 139211 [details]
dmesg output pp_num_states

Testing upstream kernel (4.17.0-rc2-ga27fc14219f2) because of the newly introduced "wattman" functionality. On my CIK hardware (Hawaii/R9 290X), none of the sysfs and hwmon entries work. Writing to sysfs files like pp_sclk_od, pp_od_clk_voltage works (no error) but the hardware/driver does not react to the changes. Reading sysfs/hwmon files like power1_cap_max, pp_table, pp_od_clk_voltage print no output. Trying to read from pp_num_states even segfaults (attached is the dmesg output of the corresponding error).
Comment 1 grmat 2018-05-03 17:36:31 UTC
Overdrive doesn't work either with current stable kernel (4.16.6). Clock remains stable (as seen in amdgpu_pm_info) and reading the value gives 0:

> echo 5 | sudo tee /sys/class/drm/card0/device/pp_sclk_od
> cat /sys/class/drm/card0/device/pp_sclk_od

I can't currently tell when this issue appeared or if the feature even ever worked with this hardware, as I've never been using it.
Comment 2 Alex Deucher 2018-05-08 22:09:19 UTC
CI parts default to the legacy dpm support, you need to enable powerplay to use the new APIs.  Boot with amdgpu.dpm=1 on the kernel command line in grub to force the driver to use powerplay rather than the old dpm code.
Comment 3 grmat 2018-05-10 21:57:22 UTC
Thanks, I wasn't aware of that.

The old overdrive functionality indeed works with amdgpu.dpm=1 on 4.16. However, it doesn't on 4.17. And wattman functionality doesn't work at all; pp_od_clk_voltage prints nothing and doesn't accept anything. Is wattman even implemented for CI?

Also, do you consider enabling amdgpu.dpm for CI by default? I found the big advantage that the VRAM/MC is finally back to the lower dpm state in idle while driving a WQHD 144 Hz monitor. That saves solid 40 Watts on desktop usage.
Comment 4 grmat 2018-07-04 15:00:43 UTC
> wattman functionality doesn't work at all;
> pp_od_clk_voltage prints nothing and doesn't accept anything. Is wattman
> even implemented for CI?

@Alex Deucher: Currently on 4.17.3 w/ dpm and the situation hasn't changed. Is the wattman functionality supposed to work with CIK or not? Do you need any additional info?
Comment 5 Alex Deucher 2018-07-05 16:27:01 UTC
You need to make sure the PP_OVERDRIVE_MASK flag (bit 14) is set.  E.g., amdgpu.ppfeaturemask=0xfffd7fff
See the documentation in the driver for more:
Also, If the vbios on the particular board does not support overclocking, the functionality is not exposed on 4.17 IIRC.
Comment 6 Alex Deucher 2018-07-05 17:38:58 UTC
Append amdgpu.ppfeaturemask=0xfffd7fff to the kernel command line in grub.
Comment 7 grmat 2018-07-06 00:17:47 UTC
Thank you for your answer.

I've already set the ppfeaturemask accordingly.

cat /sys/class/drm/card0/device/pp_od_clk_voltage

returns nothing and 

[root] echo "s 7 1000 1200" > /sys/class/drm/card0/device/pp_od_clk_voltage

prints "Invalid argument"

at the time of trying to write to the file, the following is put to the kernel ring buffer:

amdgpu: [powerplay] OverDrive feature not enabled
Comment 8 Martin Peres 2019-11-19 08:37:14 UTC
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