Attachment 96294 Details for Bug 76554 – Move all ring resets before setting the HWS patch

[patch] Move all ring resets before setting the HWS patch

0001-drm-i915-Move-all-ring-resets-before-setting-the-HWS.patch (text/plain), 3.53 KB, created by Chris Wilson on 2014-03-24 15:12:19 UTC

(hide)

Description:

Filename:

MIME Type:

Creator: Chris Wilson

Created: 2014-03-24 15:12:19 UTC

Size: 3.53 KB

patch

obsolete

>From 4fb870990c35e87101d65d7ebd839593410482d6 Mon Sep 17 00:00:00 2001
>From: Chris Wilson <chris@chris-wilson.co.uk>
>Date: Fri, 21 Mar 2014 12:21:49 +0000
>Subject: [PATCH] drm/i915: Move all ring resets before setting the HWS page
>
>In commit a51435a3137ad8ae75c288c39bd2d8b2696bae8f
>Author: Naresh Kumar Kachhi <naresh.kumar.kachhi@intel.com>
>Date:   Wed Mar 12 16:39:40 2014 +0530
>
>    drm/i915: disable rings before HW status page setup
>
>we reordered stopping the rings to do so before we set the HWS register.
>However, there is an extra workaround for g45 to reset the rings twice,
>and for consistency we should apply that workaround before setting the
>HWS to be sure that the rings are truly stopped.
>
>Cc: Naresh Kumar Kachhi <naresh.kumar.kachhi@intel.com>
>Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
>---
> drivers/gpu/drm/i915/intel_ringbuffer.c | 40 ++++++++++++++++-----------------
> 1 file changed, 20 insertions(+), 20 deletions(-)
>
>diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
>index 4d672f7f158d..9470e51f0c9f 100644
>--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
>+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
>@@ -444,32 +444,30 @@ static void ring_setup_phys_status_page(struct intel_ring_buffer *ring)
> 	I915_WRITE(HWS_PGA, addr);
> }
> 
>-static int init_ring_common(struct intel_ring_buffer *ring)
>+static bool stop_ring(struct intel_ring_buffer *ring)
> {
>-	struct drm_device *dev = ring->dev;
>-	drm_i915_private_t *dev_priv = dev->dev_private;
>-	struct drm_i915_gem_object *obj = ring->obj;
>-	int ret = 0;
>-	u32 head;
>-
>-	gen6_gt_force_wake_get(dev_priv, FORCEWAKE_ALL);
>+	drm_i915_private_t *dev_priv = to_i915(ring->dev);
> 
>-	/* Stop the ring if it's running. */
> 	I915_WRITE_CTL(ring, 0);
> 	I915_WRITE_HEAD(ring, 0);
> 	ring->write_tail(ring, 0);
> 	if (wait_for_atomic((I915_READ_MODE(ring) & MODE_IDLE) != 0, 1000))
> 		DRM_ERROR("%s :timed out trying to stop ring\n", ring->name);
> 
>-	if (I915_NEED_GFX_HWS(dev))
>-		intel_ring_setup_status_page(ring);
>-	else
>-		ring_setup_phys_status_page(ring);
>+	return I915_READ_HEAD(ring) & HEAD_ADDR;
>+}
> 
>-	head = I915_READ_HEAD(ring) & HEAD_ADDR;
>+static int init_ring_common(struct intel_ring_buffer *ring)
>+{
>+	struct drm_device *dev = ring->dev;
>+	drm_i915_private_t *dev_priv = dev->dev_private;
>+	struct drm_i915_gem_object *obj = ring->obj;
>+	int ret = 0;
> 
>-	/* G45 ring initialization fails to reset head to zero */
>-	if (head != 0) {
>+	gen6_gt_force_wake_get(dev_priv, FORCEWAKE_ALL);
>+
>+	if (stop_ring(ring)) {
>+		/* G45 ring initialization often fails to reset head to zero */
> 		DRM_DEBUG_KMS("%s head not reset to zero "
> 			      "ctl %08x head %08x tail %08x start %08x\n",
> 			      ring->name,
>@@ -478,9 +476,7 @@ static int init_ring_common(struct intel_ring_buffer *ring)
> 			      I915_READ_TAIL(ring),
> 			      I915_READ_START(ring));
> 
>-		I915_WRITE_HEAD(ring, 0);
>-
>-		if (I915_READ_HEAD(ring) & HEAD_ADDR) {
>+		if (stop_ring(ring))
> 			DRM_ERROR("failed to set %s head to zero "
> 				  "ctl %08x head %08x tail %08x start %08x\n",
> 				  ring->name,
>@@ -488,9 +484,13 @@ static int init_ring_common(struct intel_ring_buffer *ring)
> 				  I915_READ_HEAD(ring),
> 				  I915_READ_TAIL(ring),
> 				  I915_READ_START(ring));
>-		}
> 	}
> 
>+	if (I915_NEED_GFX_HWS(dev))
>+		intel_ring_setup_status_page(ring);
>+	else
>+		ring_setup_phys_status_page(ring);
>+
> 	/* Initialize the ring. This must happen _after_ we've cleared the ring
> 	 * registers with the above sequence (the readback of the HEAD registers
> 	 * also enforces ordering), otherwise the hw might lose the new ring
>-- 
>1.9.1
>

Actions: View | Splinter Review

Attachments on bug 76554: 96294 | 96298 | 96304 | 96305 | 96307 | 96311 | 96323 | 96406 | 96776 | 96783 | 97027 | 97034 | 97035 | 97036 | 97739 | 97744 | 97747 | 97756 | 97774 | 99172 | 104181 | 104208 | 104212 | 104216 | 104224 | 104226 | 104227 | 106514 | 107730

Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.