]> git.baikalelectronics.ru Git - kernel.git/commit
drm/i915: Fix __intel_wait_for_register_fw to not sleep in atomic
authorDaniel Vetter <daniel.vetter@ffwll.ch>
Wed, 10 May 2017 15:19:32 +0000 (17:19 +0200)
committerDaniel Vetter <daniel.vetter@ffwll.ch>
Wed, 10 May 2017 18:06:41 +0000 (20:06 +0200)
commitdf3bb73e679f074709ac5cc506e60a6ed12465c2
tree86a0b07e6268b8acf7a230c53a62828cb9c854fc
parentea0ea86491700cb7ba2d747f464a581023e6cc60
drm/i915: Fix __intel_wait_for_register_fw to not sleep in atomic

The unconditionally fallback to the blocking wait_for resulted in
impressive fireworks at boot-up on my snb here. Make sure if we set
the slow timeout to 0 that we never ever sleep. The tail of the
callchain was

intel_wait_for_register
-> __intel_wait_for_register_fw
  -> usleep_range
     -> BOOM

It blew up in intel_crt_detect load detection code on the
ADPA_CRT_HOTPLUG_FORCE_TRIGGER in the ADPA register.

v2: Shut up gcc.

v3: Use uninitialized_var() (Chris).

Fixes: 843f9509c800 ("drm/i915: Acquire uncore.lock over intel_uncore_wait_for_register()")
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1494429572-15118-1-git-send-email-daniel.vetter@ffwll.ch
drivers/gpu/drm/i915/intel_uncore.c