drm/i915: Don't pretend that gen2 has a hardware frame counter

Gen2 doesn't have a hardware frame counter that can be read out. Just
provide a stub .get_vblank_counter() that always returns 0 instead of
trying to read non-existing registers.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Ville Syrjälä 2013-10-11 21:52:44 +03:00 committed by Daniel Vetter
parent 7c06b08a30
commit 4cdb83ec9a

View file

@ -518,6 +518,12 @@ i915_pipe_enabled(struct drm_device *dev, int pipe)
}
}
static u32 i8xx_get_vblank_counter(struct drm_device *dev, int pipe)
{
/* Gen2 doesn't have a hardware frame counter */
return 0;
}
/* Called from drm generic code, passed a 'crtc', which
* we use as a pipe index
*/
@ -3245,7 +3251,10 @@ void intel_irq_init(struct drm_device *dev)
pm_qos_add_request(&dev_priv->pm_qos, PM_QOS_CPU_DMA_LATENCY, PM_QOS_DEFAULT_VALUE);
if (IS_G4X(dev) || INTEL_INFO(dev)->gen >= 5) {
if (IS_GEN2(dev)) {
dev->max_vblank_count = 0;
dev->driver->get_vblank_counter = i8xx_get_vblank_counter;
} else if (IS_G4X(dev) || INTEL_INFO(dev)->gen >= 5) {
dev->max_vblank_count = 0xffffffff; /* full 32 bit counter */
dev->driver->get_vblank_counter = gm45_get_vblank_counter;
} else {