Attachment 36463 Details for Bug 25345 – Don't queue during flip pending

[patch] Don't queue during flip pending

0001-drm-i915-don-t-queue-flips-during-a-flip-pending-eve.patch (text/plain), 1.73 KB, created by Chris Wilson on 2010-06-24 08:05:13 UTC

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Creator: Chris Wilson

Created: 2010-06-24 08:05:13 UTC

Size: 1.73 KB

patch

obsolete

>From a53925d44f1e8b66cd0aed163af656991c414492 Mon Sep 17 00:00:00 2001
>From: Jesse Barnes <jbarnes@virtuousgeek.org>
>Date: Mon, 5 Apr 2010 14:03:51 -0700
>Subject: [PATCH 1/2] drm/i915: don't queue flips during a flip pending event
>
>Hardware will set the flip pending ISR bit as soon as it receives the
>flip instruction, and (supposedly) clear it once the flip completes
>(e.g. at the next vblank).  If we try to send down a flip instruction
>while the ISR bit is set, the hardware can become very confused, and we
>may never receive the corresponding flip pending interrupt, effectively
>hanging the chip.
>
>Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
>---
> drivers/gpu/drm/i915/intel_display.c |   11 +++++++++++
> 1 files changed, 11 insertions(+), 0 deletions(-)
>
>diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
>index 88a1ab7..f460761 100644
>--- a/drivers/gpu/drm/i915/intel_display.c
>+++ b/drivers/gpu/drm/i915/intel_display.c
>@@ -4664,6 +4664,7 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc,
> 	unsigned long flags;
> 	int pipesrc_reg = (intel_crtc->pipe == 0) ? PIPEASRC : PIPEBSRC;
> 	int ret, pipesrc;
>+	u32 flip_mask;
> 
> 	work = kzalloc(sizeof *work, GFP_KERNEL);
> 	if (work == NULL)
>@@ -4717,6 +4718,16 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc,
> 	atomic_inc(&obj_priv->pending_flip);
> 	work->pending_flip_obj = obj;
> 
>+	if (intel_crtc->plane)
>+		flip_mask = I915_DISPLAY_PLANE_B_FLIP_PENDING_INTERRUPT;
>+	else
>+		flip_mask = I915_DISPLAY_PLANE_A_FLIP_PENDING_INTERRUPT;
>+
>+	/* Wait for any previous flip to finish */
>+	if (IS_GEN3(dev))
>+		while (I915_READ(ISR) & flip_mask)
>+			;
>+
> 	BEGIN_LP_RING(4);
> 	OUT_RING(MI_DISPLAY_FLIP |
> 		 MI_DISPLAY_FLIP_PLANE(intel_crtc->plane));
>-- 
>1.6.6.1
>

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Attachments on bug 25345: 31558 | 31668 | 31669 | 31670 | 31671 | 31672 | 31673 | 31674 | 31675 | 31695 | 34337 | 34338 | 34339 | 36460 | 36461 | 36462 | 36463 | 36464

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