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drm/i915: fixup i915_pipe_enabled check in i915_irq.c 

Well, as well as we can without completely revamping the drm vblank
code. The issue are that
- The vblank code needs to work on both ums and kms.
- It deals always deals with pipes.
- It doesn't take any of the kms locks.

The last part is not really fixable without revamping the drm vblank
code, since the drm core <-> driver interactions is a veritable pile
of spaghettis. But the other pieces can be fixed by switching on the
MODESET driver flag and either checking the hw state directly (ums
case) or just querying our sw tracking (with broken locking, but
that's not worse than what we've had).

Note that this essentially reverts

commit 702e7a56af
Author: Paulo Zanoni <paulo.r.zanoni@intel.com>
Date:   Tue Oct 23 18:29:59 2012 -0200

    drm/i915: convert PIPECONF to use transcoder instead of pipe

for the ums case, which will fix a NULL deref (since we really don't
have any crtcs set up).

But the real reason to do this is to drop our reliance on the
cpu_transcoder: By only checking intel_crtc->active we don't need to
make sure that the pipe_config (or at least the cpu_transcoder)
contain safe values even when the pipe is off.

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Damien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Daniel Vetter 2013-05-22 00:50:23 +02:00
parent 55aab33e89
commit a01025afa8
1 changed files with 8 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
drivers/gpu/drm/i915/i915_irq.c
View File

@ -381,14 +381,16 @@ static int
i915_pipe_enabled(struct drm_device *dev, int pipe)
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
enum transcoder cpu_transcoder = intel_pipe_to_cpu_transcoder(dev_priv,
pipe);
if (!intel_display_power_enabled(dev,
POWER_DOMAIN_TRANSCODER(cpu_transcoder)))
return false;
if (drm_core_check_feature(dev, DRIVER_MODESET)) {
/* Locking is horribly broken here, but whatever. */
struct drm_crtc *crtc = dev_priv->pipe_to_crtc_mapping[pipe];
struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
return I915_READ(PIPECONF(cpu_transcoder)) & PIPECONF_ENABLE;
return intel_crtc->active;
} else {
return I915_READ(PIPECONF(pipe)) & PIPECONF_ENABLE;
}
}
/* Called from drm generic code, passed a 'crtc', which