Attachment 41720 Details for Bug 30364 – Use PM QoS latency to keep CPU from dropping below C1 when vblanks enabled

[patch] Use PM QoS latency to keep CPU from dropping below C1 when vblanks enabled

i915-fix-vsync-missing-945.diff (text/plain), 2.13 KB, created by Alexander Lam on 2011-01-06 11:34:17 UTC

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Creator: Alexander Lam

Created: 2011-01-06 11:34:17 UTC

Size: 2.13 KB

patch

obsolete

>diff -uNrp linux-2.6.37-orig//drivers/gpu/drm/i915/i915_drv.h linux-2.6.37-changes//drivers/gpu/drm/i915/i915_drv.h
>--- linux-2.6.37-orig//drivers/gpu/drm/i915/i915_drv.h	2011-01-04 19:50:19.000000000 -0500
>+++ linux-2.6.37-changes//drivers/gpu/drm/i915/i915_drv.h	2011-01-06 02:36:02.428999999 -0500
>@@ -35,6 +35,7 @@
> #include "intel_ringbuffer.h"
> #include <linux/io-mapping.h>
> #include <linux/i2c.h>
>+#include <linux/pm_qos_params.h>
> #include <drm/intel-gtt.h>
> 
> /* General customization:
>@@ -674,6 +675,7 @@ typedef struct drm_i915_private {
> 	int lvds_downclock;
> 	struct work_struct idle_work;
> 	struct timer_list idle_timer;
>+	struct pm_qos_request_list pm_qos;
> 	bool busy;
> 	u16 orig_clock;
> 	int child_dev_num;
>diff -uNrp linux-2.6.37-orig//drivers/gpu/drm/i915/i915_irq.c linux-2.6.37-changes//drivers/gpu/drm/i915/i915_irq.c
>--- linux-2.6.37-orig//drivers/gpu/drm/i915/i915_irq.c	2011-01-04 19:50:19.000000000 -0500
>+++ linux-2.6.37-changes//drivers/gpu/drm/i915/i915_irq.c	2011-01-06 02:42:38.713000011 -0500
>@@ -1216,10 +1216,20 @@ int i915_enable_vblank(struct drm_device
> 	else if (INTEL_INFO(dev)->gen >= 4)
> 		i915_enable_pipestat(dev_priv, pipe,
> 				     PIPE_START_VBLANK_INTERRUPT_ENABLE);
>-	else
>+	else {
> 		i915_enable_pipestat(dev_priv, pipe,
> 				     PIPE_VBLANK_INTERRUPT_ENABLE);
>+	}
> 	spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
>+
>+	if (( IS_I945G(dev) || IS_I945GM(dev)) && !dev_priv->pm_qos.pm_qos_class)
>+	/* Install a handle to prevent C-state starvation of the GPU
>+	 * 945 platforms have an issue with vsync interrupts not
>+	 * reaching cpu during deep c-state sleep (>C1)
>+	 */
>+		pm_qos_add_request(&dev_priv->pm_qos,
>+				   PM_QOS_CPU_DMA_LATENCY,
>+				   15); //>=20 won't work
> 	return 0;
> }
> 
>@@ -1231,6 +1241,9 @@ void i915_disable_vblank(struct drm_devi
> 	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
> 	unsigned long irqflags;
> 
>+	if ((IS_I945G(dev) || IS_I945GM(dev)) && dev_priv->pm_qos.pm_qos_class)
>+		pm_qos_remove_request(&dev_priv->pm_qos);
>+
> 	spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
> 	if (HAS_PCH_SPLIT(dev))
> 		ironlake_disable_display_irq(dev_priv, (pipe == 0) ?

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Attachments on bug 30364: 38937 | 38938 | 38939 | 39347 | 40923 | 41720 | 41721 | 41796 | 41814 | 42959 | 44065

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