diff options
| author | Chris Wilson <chris@chris-wilson.co.uk> | 2010-08-07 11:01:35 +0100 |
|---|---|---|
| committer | Eric Anholt <eric@anholt.net> | 2010-08-09 11:24:35 -0700 |
| commit | 913d8d110078788c14812dce8bb62c37946821d2 (patch) | |
| tree | 982a622078194b438bf75d0ee4c77cf1e4f0260e /drivers/gpu/drm/i915/intel_drv.h | |
| parent | dd785e35cb3c430c2290d351e67715864f7e5db5 (diff) | |
drm/i915: Ensure that while(INREG()) are bounded (v2)
Add a new macro, wait_for, to simplify the act of waiting on a register
to change state. wait_for() takes three arguments, the condition to
inspect on every loop, the maximum amount of time to wait and whether to
yield the cpu for a length of time after each check.
v2: Upgrade failure messages to DRM_ERROR on the suggestion of
Eric Anholt. We do not expect to hit these conditions as they reflect
programming errors, so if we do we want to be notified.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>
Diffstat (limited to 'drivers/gpu/drm/i915/intel_drv.h')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_drv.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index c552b06e5d21..2a3eaaf64b24 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -32,6 +32,20 @@ #include "drm_crtc.h" #include "drm_crtc_helper.h" + +#define wait_for(COND, MS, W) ({ \ + unsigned long timeout__ = jiffies + msecs_to_jiffies(MS); \ + int ret__ = 0; \ + while (! (COND)) { \ + if (time_after(jiffies, timeout__)) { \ + ret__ = -ETIMEDOUT; \ + break; \ + } \ + if (W) msleep(W); \ + } \ + ret__; \ +}) + /* * Display related stuff */ |