Merge tag 'drm-intel-fixes-2015-12-23' of git://anongit.freedesktop.org/drm-intel

Pull i915 drm fixes from Jani Nikula:
 "Here's a batch of i915 fixes all around.  It may be slightly bigger
  than one would hope for at this stage, but they've all been through
  testing in our -next before being picked up for v4.4.  Also, I missed
  Dave's fixes pull earlier today just because I wanted an extra testing
  round on this.  So I'm fairly confident.

  Wishing you all the things it is customary to wish this time of the
  year"

* tag 'drm-intel-fixes-2015-12-23' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: Correct max delay for HDMI hotplug live status checking
  drm/i915: mdelay(10) considered harmful
  drm/i915: Kill intel_crtc->cursor_bo
  drm/i915: Workaround CHV pipe C cursor fail
  drm/i915: Only spin whilst waiting on the current request
  drm/i915: Limit the busy wait on requests to 5us not 10ms!
  drm/i915: Break busywaiting for requests on pending signals
  drm/i915: Disable primary plane if we fail to reconstruct BIOS fb (v2)
  drm/i915: Set the map-and-fenceable flag for preallocated objects
  drm/i915: Drop the broken cursor base==0 special casing

7 files changed, 154 insertions, 61 deletions

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index a01e51581c4c..f4af19a0d569 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2193,8 +2193,17 @@ struct drm_i915_gem_request {
 	struct drm_i915_private *i915;
 	struct intel_engine_cs *ring;
 
-	/** GEM sequence number associated with this request. */
-	uint32_t seqno;
+	 /** GEM sequence number associated with the previous request,
+	  * when the HWS breadcrumb is equal to this the GPU is processing
+	  * this request.
+	  */
+	u32 previous_seqno;
+
+	 /** GEM sequence number associated with this request,
+	  * when the HWS breadcrumb is equal or greater than this the GPU
+	  * has finished processing this request.
+	  */
+	u32 seqno;
 
 	/** Position in the ringbuffer of the start of the request */
 	u32 head;
@@ -2839,6 +2848,7 @@ i915_gem_object_ggtt_pin(struct drm_i915_gem_object *obj,
 
 int i915_vma_bind(struct i915_vma *vma, enum i915_cache_level cache_level,
 		  u32 flags);
+void __i915_vma_set_map_and_fenceable(struct i915_vma *vma);
 int __must_check i915_vma_unbind(struct i915_vma *vma);
 /*
  * BEWARE: Do not use the function below unless you can _absolutely_
@@ -2910,15 +2920,17 @@ i915_seqno_passed(uint32_t seq1, uint32_t seq2)
 	return (int32_t)(seq1 - seq2) >= 0;
 }
 
+static inline bool i915_gem_request_started(struct drm_i915_gem_request *req,
+					   bool lazy_coherency)
+{
+	u32 seqno = req->ring->get_seqno(req->ring, lazy_coherency);
+	return i915_seqno_passed(seqno, req->previous_seqno);
+}
+
 static inline bool i915_gem_request_completed(struct drm_i915_gem_request *req,
 					      bool lazy_coherency)
 {
-	u32 seqno;
-
-	BUG_ON(req == NULL);
-
-	seqno = req->ring->get_seqno(req->ring, lazy_coherency);
-
+	u32 seqno = req->ring->get_seqno(req->ring, lazy_coherency);
 	return i915_seqno_passed(seqno, req->seqno);
 }
 
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 32e6aade6223..f56af0aaafde 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -1146,23 +1146,74 @@ static bool missed_irq(struct drm_i915_private *dev_priv,
 	return test_bit(ring->id, &dev_priv->gpu_error.missed_irq_rings);
 }
 
-static int __i915_spin_request(struct drm_i915_gem_request *req)
+static unsigned long local_clock_us(unsigned *cpu)
+{
+	unsigned long t;
+
+	/* Cheaply and approximately convert from nanoseconds to microseconds.
+	 * The result and subsequent calculations are also defined in the same
+	 * approximate microseconds units. The principal source of timing
+	 * error here is from the simple truncation.
+	 *
+	 * Note that local_clock() is only defined wrt to the current CPU;
+	 * the comparisons are no longer valid if we switch CPUs. Instead of
+	 * blocking preemption for the entire busywait, we can detect the CPU
+	 * switch and use that as indicator of system load and a reason to
+	 * stop busywaiting, see busywait_stop().
+	 */
+	*cpu = get_cpu();
+	t = local_clock() >> 10;
+	put_cpu();
+
+	return t;
+}
+
+static bool busywait_stop(unsigned long timeout, unsigned cpu)
+{
+	unsigned this_cpu;
+
+	if (time_after(local_clock_us(&this_cpu), timeout))
+		return true;
+
+	return this_cpu != cpu;
+}
+
+static int __i915_spin_request(struct drm_i915_gem_request *req, int state)
 {
 	unsigned long timeout;
+	unsigned cpu;
+
+	/* When waiting for high frequency requests, e.g. during synchronous
+	 * rendering split between the CPU and GPU, the finite amount of time
+	 * required to set up the irq and wait upon it limits the response
+	 * rate. By busywaiting on the request completion for a short while we
+	 * can service the high frequency waits as quick as possible. However,
+	 * if it is a slow request, we want to sleep as quickly as possible.
+	 * The tradeoff between waiting and sleeping is roughly the time it
+	 * takes to sleep on a request, on the order of a microsecond.
+	 */
 
-	if (i915_gem_request_get_ring(req)->irq_refcount)
+	if (req->ring->irq_refcount)
 		return -EBUSY;
 
-	timeout = jiffies + 1;
+	/* Only spin if we know the GPU is processing this request */
+	if (!i915_gem_request_started(req, true))
+		return -EAGAIN;
+
+	timeout = local_clock_us(&cpu) + 5;
 	while (!need_resched()) {
 		if (i915_gem_request_completed(req, true))
 			return 0;
 
-		if (time_after_eq(jiffies, timeout))
+		if (signal_pending_state(state, current))
+			break;
+
+		if (busywait_stop(timeout, cpu))
 			break;
 
 		cpu_relax_lowlatency();
 	}
+
 	if (i915_gem_request_completed(req, false))
 		return 0;
 
@@ -1197,6 +1248,7 @@ int __i915_wait_request(struct drm_i915_gem_request *req,
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	const bool irq_test_in_progress =
 		ACCESS_ONCE(dev_priv->gpu_error.test_irq_rings) & intel_ring_flag(ring);
+	int state = interruptible ? TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE;
 	DEFINE_WAIT(wait);
 	unsigned long timeout_expire;
 	s64 before, now;
@@ -1229,7 +1281,7 @@ int __i915_wait_request(struct drm_i915_gem_request *req,
 	before = ktime_get_raw_ns();
 
 	/* Optimistic spin for the next jiffie before touching IRQs */
-	ret = __i915_spin_request(req);
+	ret = __i915_spin_request(req, state);
 	if (ret == 0)
 		goto out;
 
@@ -1241,8 +1293,7 @@ int __i915_wait_request(struct drm_i915_gem_request *req,
 	for (;;) {
 		struct timer_list timer;
 
-		prepare_to_wait(&ring->irq_queue, &wait,
-				interruptible ? TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE);
+		prepare_to_wait(&ring->irq_queue, &wait, state);
 
 		/* We need to check whether any gpu reset happened in between
 		 * the caller grabbing the seqno and now ... */
@@ -1260,7 +1311,7 @@ int __i915_wait_request(struct drm_i915_gem_request *req,
 			break;
 		}
 
-		if (interruptible && signal_pending(current)) {
+		if (signal_pending_state(state, current)) {
 			ret = -ERESTARTSYS;
 			break;
 		}
@@ -2554,6 +2605,7 @@ void __i915_add_request(struct drm_i915_gem_request *request,
 	request->batch_obj = obj;
 
 	request->emitted_jiffies = jiffies;
+	request->previous_seqno = ring->last_submitted_seqno;
 	ring->last_submitted_seqno = request->seqno;
 	list_add_tail(&request->list, &ring->request_list);
 
@@ -4080,6 +4132,29 @@ i915_vma_misplaced(struct i915_vma *vma, uint32_t alignment, uint64_t flags)
 	return false;
 }
 
+void __i915_vma_set_map_and_fenceable(struct i915_vma *vma)
+{
+	struct drm_i915_gem_object *obj = vma->obj;
+	bool mappable, fenceable;
+	u32 fence_size, fence_alignment;
+
+	fence_size = i915_gem_get_gtt_size(obj->base.dev,
+					   obj->base.size,
+					   obj->tiling_mode);
+	fence_alignment = i915_gem_get_gtt_alignment(obj->base.dev,
+						     obj->base.size,
+						     obj->tiling_mode,
+						     true);
+
+	fenceable = (vma->node.size == fence_size &&
+		     (vma->node.start & (fence_alignment - 1)) == 0);
+
+	mappable = (vma->node.start + fence_size <=
+		    to_i915(obj->base.dev)->gtt.mappable_end);
+
+	obj->map_and_fenceable = mappable && fenceable;
+}
+
 static int
 i915_gem_object_do_pin(struct drm_i915_gem_object *obj,
 		       struct i915_address_space *vm,
@@ -4147,25 +4222,7 @@ i915_gem_object_do_pin(struct drm_i915_gem_object *obj,
 
 	if (ggtt_view && ggtt_view->type == I915_GGTT_VIEW_NORMAL &&
 	    (bound ^ vma->bound) & GLOBAL_BIND) {
-		bool mappable, fenceable;
-		u32 fence_size, fence_alignment;
-
-		fence_size = i915_gem_get_gtt_size(obj->base.dev,
-						   obj->base.size,
-						   obj->tiling_mode);
-		fence_alignment = i915_gem_get_gtt_alignment(obj->base.dev,
-							     obj->base.size,
-							     obj->tiling_mode,
-							     true);
-
-		fenceable = (vma->node.size == fence_size &&
-			     (vma->node.start & (fence_alignment - 1)) == 0);
-
-		mappable = (vma->node.start + fence_size <=
-			    dev_priv->gtt.mappable_end);
-
-		obj->map_and_fenceable = mappable && fenceable;
-
+		__i915_vma_set_map_and_fenceable(vma);
 		WARN_ON(flags & PIN_MAPPABLE && !obj->map_and_fenceable);
 	}
 
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 43f35d12b677..86c7500454b4 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -2676,6 +2676,7 @@ static int i915_gem_setup_global_gtt(struct drm_device *dev,
 			return ret;
 		}
 		vma->bound |= GLOBAL_BIND;
+		__i915_vma_set_map_and_fenceable(vma);
 		list_add_tail(&vma->mm_list, &ggtt_vm->inactive_list);
 	}
 
diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
index cdacf3f5b77a..87e919a06b27 100644
--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -687,6 +687,7 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
 		}
 
 		vma->bound |= GLOBAL_BIND;
+		__i915_vma_set_map_and_fenceable(vma);
 		list_add_tail(&vma->mm_list, &ggtt->inactive_list);
 	}
 
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 62211abe4922..beb0374a19f1 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -116,6 +116,7 @@ static void skylake_pfit_enable(struct intel_crtc *crtc);
 static void ironlake_pfit_disable(struct intel_crtc *crtc, bool force);
 static void ironlake_pfit_enable(struct intel_crtc *crtc);
 static void intel_modeset_setup_hw_state(struct drm_device *dev);
+static void intel_pre_disable_primary(struct drm_crtc *crtc);
 
 typedef struct {
 	int	min, max;
@@ -2607,6 +2608,8 @@ intel_find_initial_plane_obj(struct intel_crtc *intel_crtc,
 	struct drm_i915_gem_object *obj;
 	struct drm_plane *primary = intel_crtc->base.primary;
 	struct drm_plane_state *plane_state = primary->state;
+	struct drm_crtc_state *crtc_state = intel_crtc->base.state;
+	struct intel_plane *intel_plane = to_intel_plane(primary);
 	struct drm_framebuffer *fb;
 
 	if (!plane_config->fb)
@@ -2643,6 +2646,18 @@ intel_find_initial_plane_obj(struct intel_crtc *intel_crtc,
 		}
 	}
 
+	/*
+	 * We've failed to reconstruct the BIOS FB.  Current display state
+	 * indicates that the primary plane is visible, but has a NULL FB,
+	 * which will lead to problems later if we don't fix it up.  The
+	 * simplest solution is to just disable the primary plane now and
+	 * pretend the BIOS never had it enabled.
+	 */
+	to_intel_plane_state(plane_state)->visible = false;
+	crtc_state->plane_mask &= ~(1 << drm_plane_index(primary));
+	intel_pre_disable_primary(&intel_crtc->base);
+	intel_plane->disable_plane(primary, &intel_crtc->base);
+
 	return;
 
 valid_fb:
@@ -9910,14 +9925,14 @@ static bool haswell_get_pipe_config(struct intel_crtc *crtc,
 	return true;
 }
 
-static void i845_update_cursor(struct drm_crtc *crtc, u32 base)
+static void i845_update_cursor(struct drm_crtc *crtc, u32 base, bool on)
 {
 	struct drm_device *dev = crtc->dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
 	uint32_t cntl = 0, size = 0;
 
-	if (base) {
+	if (on) {
 		unsigned int width = intel_crtc->base.cursor->state->crtc_w;
 		unsigned int height = intel_crtc->base.cursor->state->crtc_h;
 		unsigned int stride = roundup_pow_of_two(width) * 4;
@@ -9972,16 +9987,15 @@ static void i845_update_cursor(struct drm_crtc *crtc, u32 base)
 	}
 }
 
-static void i9xx_update_cursor(struct drm_crtc *crtc, u32 base)
+static void i9xx_update_cursor(struct drm_crtc *crtc, u32 base, bool on)
 {
 	struct drm_device *dev = crtc->dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
 	int pipe = intel_crtc->pipe;
-	uint32_t cntl;
+	uint32_t cntl = 0;
 
-	cntl = 0;
-	if (base) {
+	if (on) {
 		cntl = MCURSOR_GAMMA_ENABLE;
 		switch (intel_crtc->base.cursor->state->crtc_w) {
 			case 64:
@@ -10032,18 +10046,17 @@ static void intel_crtc_update_cursor(struct drm_crtc *crtc,
 	int y = cursor_state->crtc_y;
 	u32 base = 0, pos = 0;
 
-	if (on)
-		base = intel_crtc->cursor_addr;
+	base = intel_crtc->cursor_addr;
 
 	if (x >= intel_crtc->config->pipe_src_w)
-		base = 0;
+		on = false;
 
 	if (y >= intel_crtc->config->pipe_src_h)
-		base = 0;
+		on = false;
 
 	if (x < 0) {
 		if (x + cursor_state->crtc_w <= 0)
-			base = 0;
+			on = false;
 
 		pos |= CURSOR_POS_SIGN << CURSOR_X_SHIFT;
 		x = -x;
@@ -10052,16 +10065,13 @@ static void intel_crtc_update_cursor(struct drm_crtc *crtc,
 
 	if (y < 0) {
 		if (y + cursor_state->crtc_h <= 0)
-			base = 0;
+			on = false;
 
 		pos |= CURSOR_POS_SIGN << CURSOR_Y_SHIFT;
 		y = -y;
 	}
 	pos |= y << CURSOR_Y_SHIFT;
 
-	if (base == 0 && intel_crtc->cursor_base == 0)
-		return;
-
 	I915_WRITE(CURPOS(pipe), pos);
 
 	/* ILK+ do this automagically */
@@ -10072,9 +10082,9 @@ static void intel_crtc_update_cursor(struct drm_crtc *crtc,
 	}
 
 	if (IS_845G(dev) || IS_I865G(dev))
-		i845_update_cursor(crtc, base);
+		i845_update_cursor(crtc, base, on);
 	else
-		i9xx_update_cursor(crtc, base);
+		i9xx_update_cursor(crtc, base, on);
 }
 
 static bool cursor_size_ok(struct drm_device *dev,
@@ -13718,6 +13728,7 @@ intel_check_cursor_plane(struct drm_plane *plane,
 	struct drm_crtc *crtc = crtc_state->base.crtc;
 	struct drm_framebuffer *fb = state->base.fb;
 	struct drm_i915_gem_object *obj = intel_fb_obj(fb);
+	enum pipe pipe = to_intel_plane(plane)->pipe;
 	unsigned stride;
 	int ret;
 
@@ -13751,6 +13762,22 @@ intel_check_cursor_plane(struct drm_plane *plane,
 		return -EINVAL;
 	}
 
+	/*
+	 * There's something wrong with the cursor on CHV pipe C.
+	 * If it straddles the left edge of the screen then
+	 * moving it away from the edge or disabling it often
+	 * results in a pipe underrun, and often that can lead to
+	 * dead pipe (constant underrun reported, and it scans
+	 * out just a solid color). To recover from that, the
+	 * display power well must be turned off and on again.
+	 * Refuse the put the cursor into that compromised position.
+	 */
+	if (IS_CHERRYVIEW(plane->dev) && pipe == PIPE_C &&
+	    state->visible && state->base.crtc_x < 0) {
+		DRM_DEBUG_KMS("CHV cursor C not allowed to straddle the left screen edge\n");
+		return -EINVAL;
+	}
+
 	return 0;
 }
 
@@ -13774,9 +13801,6 @@ intel_commit_cursor_plane(struct drm_plane *plane,
 	crtc = crtc ? crtc : plane->crtc;
 	intel_crtc = to_intel_crtc(crtc);
 
-	if (intel_crtc->cursor_bo == obj)
-		goto update;
-
 	if (!obj)
 		addr = 0;
 	else if (!INTEL_INFO(dev)->cursor_needs_physical)
@@ -13785,9 +13809,7 @@ intel_commit_cursor_plane(struct drm_plane *plane,
 		addr = obj->phys_handle->busaddr;
 
 	intel_crtc->cursor_addr = addr;
-	intel_crtc->cursor_bo = obj;
 
-update:
 	if (crtc->state->active)
 		intel_crtc_update_cursor(crtc, state->visible);
 }
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index f2a1142bff34..0d00f07b7163 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -550,7 +550,6 @@ struct intel_crtc {
 	int adjusted_x;
 	int adjusted_y;
 
-	struct drm_i915_gem_object *cursor_bo;
 	uint32_t cursor_addr;
 	uint32_t cursor_cntl;
 	uint32_t cursor_size;
diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
index 81cdd9ff3892..64086f2d4e26 100644
--- a/drivers/gpu/drm/i915/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/intel_hdmi.c
@@ -1374,17 +1374,18 @@ intel_hdmi_detect(struct drm_connector *connector, bool force)
 	struct intel_hdmi *intel_hdmi = intel_attached_hdmi(connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->dev);
 	bool live_status = false;
-	unsigned int retry = 3;
+	unsigned int try;
 
 	DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n",
 		      connector->base.id, connector->name);
 
 	intel_display_power_get(dev_priv, POWER_DOMAIN_GMBUS);
 
-	while (!live_status && --retry) {
+	for (try = 0; !live_status && try < 4; try++) {
+		if (try)
+			msleep(10);
 		live_status = intel_digital_port_connected(dev_priv,
 				hdmi_to_dig_port(intel_hdmi));
-		mdelay(10);
 	}
 
 	if (!live_status)