Comment 35 for bug 1848771

I don't know if this is related but it fixed my problem with wake up from suspend.
This is on a desktop with an Asus Rog Strix B450-F Gaming motherboard and Focal Fossa.

I have changed these settings in BIOS
- Used DOCP settings on the memory
- USB power delivery in SoftOff is set to Disable
- PSS support is set to enable
- Serial Port is set to OFF
In AMD CBS
- IOMMU is set to Disabled
- Global C-state control is set to enable
- Power Supply Idle Control is set to Low Current Idle

I think the most important setting is to disable IOMMU. Instead I have added "iommu=soft" in GRUB_CMDLINE_LINUX="" in /etc/default/grub