I managed to install successfully 20.20 amdgpu-pro (openCL= legacy) drivers in ubuntu 18.04.5 (HWE) with kernel 5.4.0-54.
It seems to work fine but when I run cat /sys/kernel/debug/dri/0/amdgpu_pm_info I get crazy numbers for clocks (42949672 MHz!!):
Clock Gating Flags Mask: 0x0
Graphics Medium Grain Clock Gating: Off
Graphics Medium Grain memory Light Sleep: Off
Graphics Coarse Grain Clock Gating: Off
Graphics Coarse Grain memory Light Sleep: Off
Graphics Coarse Grain Tree Shader Clock Gating: Off
Graphics Coarse Grain Tree Shader Light Sleep: Off
Graphics Command Processor Light Sleep: Off
Graphics Run List Controller Light Sleep: Off
Graphics 3D Coarse Grain Clock Gating: Off
Graphics 3D Coarse Grain memory Light Sleep: Off
Memory Controller Light Sleep: Off
Memory Controller Medium Grain Clock Gating: Off
System Direct Memory Access Light Sleep: Off
System Direct Memory Access Medium Grain Clock Gating: Off
Bus Interface Medium Grain Clock Gating: Off
Bus Interface Light Sleep: Off
Unified Video Decoder Medium Grain Clock Gating: Off
Video Compression Engine Medium Grain Clock Gating: Off
Host Data Path Light Sleep: Off
Host Data Path Medium Grain Clock Gating: Off
Digital Right Management Medium Grain Clock Gating: Off
Digital Right Management Light Sleep: Off
Rom Medium Grain Clock Gating: Off
Data Fabric Medium Grain Clock Gating: Off
Address Translation Hub Medium Grain Clock Gating: Off
Address Translation Hub Light Sleep: Off
GFX Clocks and Power:
42949672 MHz (MCLK)
42949424 MHz (SCLK)
300 MHz (PSTATE_SCLK)
150 MHz (PSTATE_MCLK)
1050 mV (VDDGFX)
45.118 W (average GPU)
GPU Temperature: 46 C
GPU Load: 0 %
MEM Load: 0 %
UVD: Disabled
VCE: Disabled
