https://bugs.freedesktop.org/show_bug.cgi?id=78453
--- Comment #31 from vincent vljn@ovi.com --- 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.