drm/i915: use _NOTRACE for gmbus/dp aux wait loops

Less clutter in the traces. And in both cases we yell rather loud
into the logs if we time out. Patch suggested by Chris Wilson.

v2: Annotate another I915_READ in dp_aux to be consistent - we filter
out all register io in wait_for and similar loops. Chris also
suggested to mark all dp_aux register access as _NOTRACE, but I think
we should keep all functionally relevant access around, and filter
unneeded bits in userspace after the trace is captured.

Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_dp.c

@@ -351,7 +351,7 @@ intel_dp_aux_wait_done(struct intel_dp *intel_dp, bool has_aux_irq)
 		}
 	}
 
-#define C (((status = I915_READ(ch_ctl)) & DP_AUX_CH_CTL_SEND_BUSY) == 0)
+#define C (((status = I915_READ_NOTRACE(ch_ctl)) & DP_AUX_CH_CTL_SEND_BUSY) == 0)
 	if (has_aux_irq)
 		done = wait_event_timeout(dev_priv->gmbus_wait_queue, C, 10);
 	else
@@ -439,7 +439,7 @@ intel_dp_aux_ch(struct intel_dp *intel_dp,
 
 	/* Try to wait for any previous AUX channel activity */
 	for (try = 0; try < 3; try++) {
-		status = I915_READ(ch_ctl);
+		status = I915_READ_NOTRACE(ch_ctl);
 		if ((status & DP_AUX_CH_CTL_SEND_BUSY) == 0)
 			break;
 		msleep(1);

drivers/gpu/drm/i915/intel_i2c.c

@@ -223,7 +223,7 @@ gmbus_wait_hw_status(struct drm_i915_private *dev_priv,
 		prepare_to_wait(&dev_priv->gmbus_wait_queue, &wait,
 				TASK_UNINTERRUPTIBLE);
 
-		gmbus2 = I915_READ(GMBUS2 + reg_offset);
+		gmbus2 = I915_READ_NOTRACE(GMBUS2 + reg_offset);
 		if (gmbus2 & (GMBUS_SATOER | gmbus2_status))
 			break;
 
@@ -246,7 +246,7 @@ gmbus_wait_idle(struct drm_i915_private *dev_priv)
 	int ret;
 	int reg_offset = dev_priv->gpio_mmio_base;
 
-#define C ((I915_READ(GMBUS2 + reg_offset) & GMBUS_ACTIVE) == 0)
+#define C ((I915_READ_NOTRACE(GMBUS2 + reg_offset) & GMBUS_ACTIVE) == 0)
 
 	if (!HAS_GMBUS_IRQ(dev_priv->dev))
 		return wait_for(C, 10);