Comment 7 for bug 1939986

I confirm on focal.
WORKAROUND, install linux-firmware package from Impish (1.201) instead of one from focal (1.187)
The many kernel errors about PCI devices dissapear during the boot time. Not sure about the real impact on the system itself.

 sudo update-initramfs -u
update-initramfs: Generating /boot/initrd.img-5.11.0-27-generic
W: Possible missing firmware /lib/firmware/i915/skl_guc_49.0.1.bin for module i915
W: Possible missing firmware /lib/firmware/i915/bxt_guc_49.0.1.bin for module i915
W: Possible missing firmware /lib/firmware/i915/kbl_guc_49.0.1.bin for module i915
W: Possible missing firmware /lib/firmware/i915/glk_guc_49.0.1.bin for module i915
W: Possible missing firmware /lib/firmware/i915/kbl_guc_49.0.1.bin for module i915
W: Possible missing firmware /lib/firmware/i915/kbl_guc_49.0.1.bin for module i915
W: Possible missing firmware /lib/firmware/i915/cml_guc_49.0.1.bin for module i915
W: Possible missing firmware /lib/firmware/i915/icl_guc_49.0.1.bin for module i915
W: Possible missing firmware /lib/firmware/i915/ehl_guc_49.0.1.bin for module i915
W: Possible missing firmware /lib/firmware/i915/ehl_guc_49.0.1.bin for module i915
W: Possible missing firmware /lib/firmware/i915/tgl_huc_7.5.0.bin for module i915
W: Possible missing firmware /lib/firmware/i915/tgl_guc_49.0.1.bin for module i915
W: Possible missing firmware /lib/firmware/i915/tgl_huc_7.5.0.bin for module i915
W: Possible missing firmware /lib/firmware/i915/tgl_guc_49.0.1.bin for module i915
W: Possible missing firmware /lib/firmware/i915/dg1_dmc_ver2_02.bin for module i915
I: The initramfs will attempt to resume from /dev/dm-2
I: (/dev/mapper/vgubuntu-swap_1)
I: Set the RESUME variable to override this.