commit 55d4e020fb upstream.
Seems to work like the DCE3 version despite what
the register spec says.
bug:
https://bugs.freedesktop.org/show_bug.cgi?id=71975
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>