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_crt.c | |
| 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_crt.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_crt.c | 17 |
1 files changed, 7 insertions, 10 deletions
diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c index cfcf85496e3..c43176d7754 100644 --- a/drivers/gpu/drm/i915/intel_crt.c +++ b/drivers/gpu/drm/i915/intel_crt.c @@ -185,8 +185,9 @@ static bool intel_ironlake_crt_detect_hotplug(struct drm_connector *connector) DRM_DEBUG_KMS("pch crt adpa 0x%x", adpa); I915_WRITE(PCH_ADPA, adpa); - while ((I915_READ(PCH_ADPA) & ADPA_CRT_HOTPLUG_FORCE_TRIGGER) != 0) - ; + if (wait_for((I915_READ(PCH_ADPA) & ADPA_CRT_HOTPLUG_FORCE_TRIGGER) == 0, + 1000, 1)) + DRM_ERROR("timed out waiting for FORCE_TRIGGER"); if (HAS_PCH_CPT(dev)) { I915_WRITE(PCH_ADPA, temp); @@ -237,17 +238,13 @@ static bool intel_crt_detect_hotplug(struct drm_connector *connector) hotplug_en |= CRT_HOTPLUG_FORCE_DETECT; for (i = 0; i < tries ; i++) { - unsigned long timeout; /* turn on the FORCE_DETECT */ I915_WRITE(PORT_HOTPLUG_EN, hotplug_en); - timeout = jiffies + msecs_to_jiffies(1000); /* wait for FORCE_DETECT to go off */ - do { - if (!(I915_READ(PORT_HOTPLUG_EN) & - CRT_HOTPLUG_FORCE_DETECT)) - break; - msleep(1); - } while (time_after(timeout, jiffies)); + if (wait_for((I915_READ(PORT_HOTPLUG_EN) & + CRT_HOTPLUG_FORCE_DETECT) == 0, + 1000, 1)) + DRM_ERROR("timed out waiting for FORCE_DETECT to go off"); } stat = I915_READ(PORT_HOTPLUG_STAT); |