Comment # 31 on bug 78453 from vincent

No luck with libdrm-2.4.48 either (roughly when hawaii pciid was added).

I'm using llvm bdbcffa4af01cda413690276d8e81b3ab5cea9b6,
mesa 469b42ee21d6bc530200c76cb0e73b0b461ab6e8 (+ MD patch)
and kernel 8d0a2215931f1ffd77aef65cae2c0becc3f5d560 with radeon.dpm=0 and
radeon.runpm=0.