Comment # 8 on bug 1190854 from Hadrien Grasland

Created attachment 853509 [details]
dmesg logs with various firmwares

I assume you meant
https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git ,
and this is what I used.

- This particular card needs firmware file polaris12_k_mc.bin to boot, which
was introduced by linux-firmware commit
6cca1381f328e7df55ae8bb8ac515b945d35f9f5 from 2018-12-03. Before that, amdgpu
will complain about the missing file and refuse to stard.
- The first functional firmware produces the same dmesg logs as the current
firmware (timestamps aside).
- I tested a couple of intermediary linux-firmware commits that touched
amdgpu/polaris*, aiming for version consistency between polaris10 and polaris12
firmware files (since the amdgpu logs mention both polaris10 and polaris12),
and the dmesg output remained identical.

So the firmware does not seem to be the culprit here...