Re: [Bug #11947] 2.6.28-rc VC switching with Intel graphics broken

[Ingo Molnar <mingo@elte.hu>]

* Bernhard Schmidt <berni@birkenwald.de> wrote:

> Hello,
>
>> On Monday, November 24, 2008 12:47 am Romano Giannetti (lists) wrote:
>>> Rafael J. Wysocki wrote:
>>>> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11947
>>>> Subject		: 2.6.28-rc VC switching with Intel graphics broken
>>>> Submitter	: Romano Giannetti <romano.giannetti@gmail.com>
>>>> Date		: 2008-11-03 12:10 (20 days old)
>>>> Handled-By	: Jesse Barnes <jbarnes@virtuousgeek.org>
>>> Still with us on -rc6, nasty, reproducible, no clues on what can be.
>>>
>>> VC switch locks or delay the systems minutes, resuming from suspend locks
>>> hard the machine.
>>>
>>> 2.6.28-rc is unusable here.
>>>
>>> Jesse, any hints? My suspicion that it can be the same thing happened with
>>> bug 10620 is wrong? (It was a very similar error about vblank...)
>>
>> Just added to the bug, it looks like a DUP of an issue Keith just fixed 
>> last week (now to make sure the patch makes it upstream quickly).
>
> I can confirm that, with the patch from  
> http://lists.freedesktop.org/archives/intel-gfx/2008-November/000614.html 
> applied on top of current git head (rejected hunk in  
> drivers/gpu/drm/i915/915_irq.c due to the additional  
> dev_priv->irq_mask_reg = ~0; in git between the removed lines, I kept  
> it) I can suspend/resume and do a VC switch again.
>
> Big thanks!

here it is below plaintext as well, merged up to latest -git.

	Ingo

------------------->
>From 60174462808051477793776c67282364bc94ded3 Mon Sep 17 00:00:00 2001
From: Keith Packard <keithp@keithp.com>
Date: Tue, 18 Nov 2008 09:30:25 -0800
Subject: [PATCH] drm: move drm vblank initialization/cleanup to driver load/unload

drm vblank initialization keeps track of the changes in driver-supplied
frame counts across vt switch and mode setting, but only if you let it by
not tearing down the drm vblank structure.

Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 drivers/gpu/drm/drm_drv.c       |    2 ++
 drivers/gpu/drm/drm_irq.c       |    4 +---
 drivers/gpu/drm/i915/i915_dma.c |    5 +++++
 drivers/gpu/drm/i915/i915_drv.h |    2 ++
 drivers/gpu/drm/i915/i915_irq.c |    5 -----
 include/drm/drmP.h              |    1 +
 6 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 3ab1e9c..996097a 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -305,6 +305,8 @@ static void drm_cleanup(struct drm_device * dev)
 		return;
 	}
 
+	drm_vblank_cleanup(dev);
+
 	drm_lastclose(dev);
 
 	if (drm_core_has_MTRR(dev) && drm_core_has_AGP(dev) &&
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 15c8dab..1e787f8 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -94,7 +94,7 @@ static void vblank_disable_fn(unsigned long arg)
 	}
 }
 
-static void drm_vblank_cleanup(struct drm_device *dev)
+void drm_vblank_cleanup(struct drm_device *dev)
 {
 	/* Bail if the driver didn't call drm_vblank_init() */
 	if (dev->num_crtcs == 0)
@@ -278,8 +278,6 @@ int drm_irq_uninstall(struct drm_device * dev)
 
 	free_irq(dev->pdev->irq, dev);
 
-	drm_vblank_cleanup(dev);
-
 	return 0;
 }
 EXPORT_SYMBOL(drm_irq_uninstall);
diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index 0d215e3..9a1450e 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -856,6 +856,11 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 
 	spin_lock_init(&dev_priv->user_irq_lock);
 
+	ret = drm_vblank_init(dev, I915_NUM_PIPE);
+
+	if (ret)
+		return ret;
+
 	return ret;
 }
 
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index ef1c0b8..ec78190 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -47,6 +47,8 @@ enum pipe {
 	PIPE_B,
 };
 
+#define I915_NUM_PIPE	2
+
 /* Interface history:
  *
  * 1.1: Original.
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 82752d6..a60af31 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -483,14 +483,9 @@ void i915_driver_irq_preinstall(struct drm_device * dev)
 int i915_driver_irq_postinstall(struct drm_device *dev)
 {
 	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
-	int ret, num_pipes = 2;
-
 	/* Set initial unmasked IRQs to just the selected vblank pipes. */
 	dev_priv->irq_mask_reg = ~0;
 
-	ret = drm_vblank_init(dev, num_pipes);
-	if (ret)
-		return ret;
 
 	dev_priv->vblank_pipe = DRM_I915_VBLANK_PIPE_A | DRM_I915_VBLANK_PIPE_B;
 	dev_priv->irq_mask_reg &= ~I915_DISPLAY_PIPE_A_VBLANK_INTERRUPT;
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 28c7f16..d5e8e5c 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -1151,6 +1151,7 @@ extern u32 drm_vblank_count(struct drm_device *dev, int crtc);
 extern void drm_handle_vblank(struct drm_device *dev, int crtc);
 extern int drm_vblank_get(struct drm_device *dev, int crtc);
 extern void drm_vblank_put(struct drm_device *dev, int crtc);
+extern void drm_vblank_cleanup(struct drm_device *dev);
 /* Modesetting support */
 extern int drm_modeset_ctl(struct drm_device *dev, void *data,
 			   struct drm_file *file_priv);