intel-gfx.lists.freedesktop.org archive mirror
 help / color / mirror / Atom feed
* [PATCH 1/2] drm/i915: check the power well when redisabling VGA
@ 2013-08-02 19:22 Paulo Zanoni
  2013-08-02 19:22 ` [PATCH 2/2] drm/i915: clarify Haswell power well bit names Paulo Zanoni
  2013-08-05 15:46 ` [PATCH 1/2] drm/i915: check the power well when redisabling VGA Daniel Vetter
  0 siblings, 2 replies; 4+ messages in thread
From: Paulo Zanoni @ 2013-08-02 19:22 UTC (permalink / raw)
  To: intel-gfx; +Cc: Paulo Zanoni

From: Paulo Zanoni <paulo.r.zanoni@intel.com>

If the power well is disabled VGA is guaranteed to be disabled.

This fixes unclaimed register messages that happen on suspend/resume.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=67517
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
---
 drivers/gpu/drm/i915/intel_display.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index e1e50df..3765d0b 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -10097,6 +10097,17 @@ void i915_redisable_vga(struct drm_device *dev)
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 vga_reg = i915_vgacntrl_reg(dev);
 
+	/* This function can be called both from intel_modeset_setup_hw_state or
+	 * at a very early point in our resume sequence, where the power well
+	 * structures are not yet restored. Since this function is at a very
+	 * paranoid "someone might have enabled VGA while we were not looking"
+	 * level, just check if the power well is enabled instead of trying to
+	 * follow the "don't touch the power well if we don't need it" policy
+	 * the rest of the driver uses. */
+	if (HAS_POWER_WELL(dev) &&
+	    (I915_READ(HSW_PWR_WELL_DRIVER) & HSW_PWR_WELL_STATE) == 0)
+		return;
+
 	if (I915_READ(vga_reg) != VGA_DISP_DISABLE) {
 		DRM_DEBUG_KMS("Something enabled VGA plane, disabling it\n");
 		i915_disable_vga(dev);
-- 
1.8.1.2

^ permalink raw reply related	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2013-08-14 14:50 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-08-02 19:22 [PATCH 1/2] drm/i915: check the power well when redisabling VGA Paulo Zanoni
2013-08-02 19:22 ` [PATCH 2/2] drm/i915: clarify Haswell power well bit names Paulo Zanoni
2013-08-05 15:46 ` [PATCH 1/2] drm/i915: check the power well when redisabling VGA Daniel Vetter
2013-08-14 14:51   ` Daniel Vetter

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).