drm/i915: fix up ilk drps/ips locking
We change the drps/ips sw/hw state from different callers: Our own irq
handler, the external intel-ips module and from process context. Most
of these callers don't take any lock at all.
Protect everything by making the mchdev_lock irqsave and grabbing it in
all relevant callsites. Note that we have to convert a few sleeps in the
drps enable/disable code to delays, but alas, I'm not volunteering to
restructure the code around a few work items.
For paranoia add a spin_locked assert to ironlake_set_drps, too.
v2: Move one access inside the lock protection. Caught by the
dev_priv->ips mass-rename ...
v3: Resolve rebase conflict.
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2 files changed