[Maverick SRU] drm/i915: Avoid pageflipping freeze when we miss the flip prepare interrupt
Tim Gardner
timg at tpi.com
Wed Nov 24 17:56:39 UTC 2010
The following changes since commit fbf6dfc88c549151dffac531e919b5b9c2b0346a:
Tim Gardner (1):
UBUNTU: Simplify the use of CROSS_COMPILER
are available in the git repository at:
git://kernel.ubuntu.com/rtg/ubuntu-maverick.git i915-page-flip-lp680204
Simon Farnsworth (1):
drm/i915: Avoid pageflipping freeze when we miss the flip prepare interrupt
drivers/gpu/drm/i915/i915_debugfs.c | 50 +++++++++++++++++++++++++++++++++
drivers/gpu/drm/i915/i915_irq.c | 51 ++++++++++++++++++++++++++++++++-
drivers/gpu/drm/i915/intel_display.c | 14 ++------
drivers/gpu/drm/i915/intel_drv.h | 10 ++++++
4 files changed, 113 insertions(+), 12 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 9214119..dfb920e 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -31,6 +31,7 @@
#include <linux/slab.h>
#include "drmP.h"
#include "drm.h"
+#include "intel_drv.h"
#include "i915_drm.h"
#include "i915_drv.h"
@@ -121,6 +122,54 @@ static int i915_gem_object_list_info(struct seq_file *m, void *data)
return 0;
}
+static int i915_gem_pageflip_info(struct seq_file *m, void *data)
+{
+ struct drm_info_node *node = (struct drm_info_node *) m->private;
+ struct drm_device *dev = node->minor->dev;
+ unsigned long flags;
+ struct intel_crtc *crtc;
+
+ list_for_each_entry(crtc, &dev->mode_config.crtc_list, base.head) {
+ const char *pipe = crtc->pipe ? "B" : "A";
+ const char *plane = crtc->plane ? "B" : "A";
+ struct intel_unpin_work *work;
+
+ spin_lock_irqsave(&dev->event_lock, flags);
+ work = crtc->unpin_work;
+ if (work == NULL) {
+ seq_printf(m, "No flip due on pipe %s (plane %s)\n",
+ pipe, plane);
+ } else {
+ if (!work->pending) {
+ seq_printf(m, "Flip queued on pipe %s (plane %s)\n",
+ pipe, plane);
+ } else {
+ seq_printf(m, "Flip pending (waiting for vsync) on pipe %s (plane %s)\n",
+ pipe, plane);
+ }
+ if (work->enable_stall_check)
+ seq_printf(m, "Stall check enabled, ");
+ else
+ seq_printf(m, "Stall check waiting for page flip ioctl, ");
+ seq_printf(m, "%d prepares\n", work->pending);
+
+ if (work->old_fb_obj) {
+ struct drm_i915_gem_object *obj_priv = to_intel_bo(work->old_fb_obj);
+ if(obj_priv)
+ seq_printf(m, "Old framebuffer gtt_offset 0x%08x\n", obj_priv->gtt_offset );
+ }
+ if (work->pending_flip_obj) {
+ struct drm_i915_gem_object *obj_priv = to_intel_bo(work->pending_flip_obj);
+ if(obj_priv)
+ seq_printf(m, "New framebuffer gtt_offset 0x%08x\n", obj_priv->gtt_offset );
+ }
+ }
+ spin_unlock_irqrestore(&dev->event_lock, flags);
+ }
+
+ return 0;
+}
+
static int i915_gem_request_info(struct seq_file *m, void *data)
{
struct drm_info_node *node = (struct drm_info_node *) m->private;
@@ -774,6 +823,7 @@ static struct drm_info_list i915_debugfs_list[] = {
{"i915_gem_active", i915_gem_object_list_info, 0, (void *) ACTIVE_LIST},
{"i915_gem_flushing", i915_gem_object_list_info, 0, (void *) FLUSHING_LIST},
{"i915_gem_inactive", i915_gem_object_list_info, 0, (void *) INACTIVE_LIST},
+ {"i915_gem_pageflip", i915_gem_pageflip_info, 0},
{"i915_gem_request", i915_gem_request_info, 0},
{"i915_gem_seqno", i915_gem_seqno_info, 0},
{"i915_gem_fence_regs", i915_gem_fence_regs_info, 0},
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index dba53d4..d57c8c2 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -834,6 +834,49 @@ static void i915_handle_error(struct drm_device *dev, bool wedged)
queue_work(dev_priv->wq, &dev_priv->error_work);
}
+static void i915_pageflip_stall_check(struct drm_device *dev, int pipe)
+{
+ drm_i915_private_t *dev_priv = dev->dev_private;
+ struct drm_crtc *crtc = dev_priv->pipe_to_crtc_mapping[pipe];
+ struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+ struct drm_i915_gem_object *obj_priv;
+ struct intel_unpin_work *work;
+ unsigned long flags;
+ bool stall_detected;
+
+ /* Ignore early vblank irqs */
+ if (intel_crtc == NULL)
+ return;
+
+ spin_lock_irqsave(&dev->event_lock, flags);
+ work = intel_crtc->unpin_work;
+
+ if (work == NULL || work->pending || !work->enable_stall_check) {
+ /* Either the pending flip IRQ arrived, or we're too early. Don't check */
+ spin_unlock_irqrestore(&dev->event_lock, flags);
+ return;
+ }
+
+ /* Potential stall - if we see that the flip has happened, assume a missed interrupt */
+ obj_priv = to_intel_bo(work->pending_flip_obj);
+ if(IS_I965G(dev)) {
+ int dspsurf = intel_crtc->plane == 0 ? DSPASURF : DSPBSURF;
+ stall_detected = I915_READ(dspsurf) == obj_priv->gtt_offset;
+ } else {
+ int dspaddr = intel_crtc->plane == 0 ? DSPAADDR : DSPBADDR;
+ stall_detected = I915_READ(dspaddr) == (obj_priv->gtt_offset +
+ crtc->y * crtc->fb->pitch +
+ crtc->x * crtc->fb->bits_per_pixel/8);
+ }
+
+ spin_unlock_irqrestore(&dev->event_lock, flags);
+
+ if (stall_detected) {
+ DRM_DEBUG_DRIVER("Pageflip stall detected\n");
+ intel_prepare_page_flip(dev, intel_crtc->plane);
+ }
+}
+
irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
{
struct drm_device *dev = (struct drm_device *) arg;
@@ -955,15 +998,19 @@ irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
if (pipea_stats & vblank_status) {
vblank++;
drm_handle_vblank(dev, 0);
- if (!dev_priv->flip_pending_is_done)
+ if (!dev_priv->flip_pending_is_done) {
+ i915_pageflip_stall_check(dev, 0);
intel_finish_page_flip(dev, 0);
+ }
}
if (pipeb_stats & vblank_status) {
vblank++;
drm_handle_vblank(dev, 1);
- if (!dev_priv->flip_pending_is_done)
+ if (!dev_priv->flip_pending_is_done) {
+ i915_pageflip_stall_check(dev, 1);
intel_finish_page_flip(dev, 1);
+ }
}
if ((pipea_stats & I915_LEGACY_BLC_EVENT_STATUS) ||
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index b0c0e2f..bf99751 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4635,15 +4635,6 @@ static void intel_crtc_destroy(struct drm_crtc *crtc)
kfree(intel_crtc);
}
-struct intel_unpin_work {
- struct work_struct work;
- struct drm_device *dev;
- struct drm_gem_object *old_fb_obj;
- struct drm_gem_object *pending_flip_obj;
- struct drm_pending_vblank_event *event;
- int pending;
-};
-
static void intel_unpin_work_fn(struct work_struct *__work)
{
struct intel_unpin_work *work =
@@ -4729,7 +4720,8 @@ void intel_prepare_page_flip(struct drm_device *dev, int plane)
spin_lock_irqsave(&dev->event_lock, flags);
if (intel_crtc->unpin_work) {
- intel_crtc->unpin_work->pending = 1;
+ if ((++intel_crtc->unpin_work->pending) > 1)
+ DRM_ERROR("Prepared flip multiple times\n");
} else {
DRM_DEBUG_DRIVER("preparing flip with no unpin work?\n");
}
@@ -4816,6 +4808,8 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc,
ADVANCE_LP_RING();
}
+ work->enable_stall_check = true;
+
/* Offset into the new buffer for cases of shared fbs between CRTCs */
offset = obj_priv->gtt_offset;
offset += (crtc->y * fb->pitch) + (crtc->x * (fb->bits_per_pixel) / 8);
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 634150b..d6c2115 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -165,6 +165,16 @@ struct intel_crtc {
#define enc_to_intel_encoder(x) container_of(x, struct intel_encoder, enc)
#define to_intel_framebuffer(x) container_of(x, struct intel_framebuffer, base)
+struct intel_unpin_work {
+ struct work_struct work;
+ struct drm_device *dev;
+ struct drm_gem_object *old_fb_obj;
+ struct drm_gem_object *pending_flip_obj;
+ struct drm_pending_vblank_event *event;
+ int pending;
+ bool enable_stall_check;
+};
+
struct i2c_adapter *intel_i2c_create(struct drm_device *dev, const u32 reg,
const char *name);
void intel_i2c_destroy(struct i2c_adapter *adapter);
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