drm/i915: Extract register state error capture

The code has become quite hairy. By relocating all the generic registers
it will become more obvious where future ones should go. There is still
admittedly a bit of confusion left for things like per ring registers.

A subsequent patch will clean this function up.
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_gpu_error.c

@@ -978,43 +978,13 @@ static void i915_gem_capture_buffers(struct drm_i915_private *dev_priv,
 		i915_gem_capture_vm(dev_priv, error, vm, i++);
 }
 
-/**
- * i915_capture_error_state - capture an error record for later analysis
- * @dev: drm device
- *
- * Should be called when an error is detected (either a hang or an error
- * interrupt) to capture error state from the time of the error.  Fills
- * out a structure which becomes available in debugfs for user level tools
- * to pick up.
- */
-void i915_capture_error_state(struct drm_device *dev)
+/* Capture all registers which don't fit into another category. */
+static void i915_capture_reg_state(struct drm_i915_private *dev_priv,
+				   struct drm_i915_error_state *error)
 {
-	struct drm_i915_private *dev_priv = dev->dev_private;
-	struct drm_i915_error_state *error;
-	unsigned long flags;
+	struct drm_device *dev = dev_priv->dev;
 	int pipe;
 
-	spin_lock_irqsave(&dev_priv->gpu_error.lock, flags);
-	error = dev_priv->gpu_error.first_error;
-	spin_unlock_irqrestore(&dev_priv->gpu_error.lock, flags);
-	if (error)
-		return;
-
-	/* Account for pipe specific data like PIPE*STAT */
-	error = kzalloc(sizeof(*error), GFP_ATOMIC);
-	if (!error) {
-		DRM_DEBUG_DRIVER("out of memory, not capturing error state\n");
-		return;
-	}
-
-	DRM_INFO("GPU crash dump saved to /sys/class/drm/card%d/error\n",
-		 dev->primary->index);
-	DRM_INFO("GPU hangs can indicate a bug anywhere in the entire gfx stack, including userspace.\n");
-	DRM_INFO("Please file a _new_ bug report on bugs.freedesktop.org against DRI -> DRM/Intel\n");
-	DRM_INFO("drm/i915 developers can then reassign to the right component if it's not a kernel issue.\n");
-	DRM_INFO("The gpu crash dump is required to analyze gpu hangs, so please always attach it.\n");
-
-	kref_init(&error->ref);
 	error->eir = I915_READ(EIR);
 	error->pgtbl_er = I915_READ(PGTBL_ER);
 	if (HAS_HW_CONTEXTS(dev))
@@ -1052,7 +1022,46 @@ void i915_capture_error_state(struct drm_device *dev)
 		error->err_int = I915_READ(GEN7_ERR_INT);
 
 	i915_get_extra_instdone(dev, error->extra_instdone);
+}
+
+/**
+ * i915_capture_error_state - capture an error record for later analysis
+ * @dev: drm device
+ *
+ * Should be called when an error is detected (either a hang or an error
+ * interrupt) to capture error state from the time of the error.  Fills
+ * out a structure which becomes available in debugfs for user level tools
+ * to pick up.
+ */
+void i915_capture_error_state(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct drm_i915_error_state *error;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev_priv->gpu_error.lock, flags);
+	error = dev_priv->gpu_error.first_error;
+	spin_unlock_irqrestore(&dev_priv->gpu_error.lock, flags);
+	if (error)
+		return;
+
+	/* Account for pipe specific data like PIPE*STAT */
+	error = kzalloc(sizeof(*error), GFP_ATOMIC);
+	if (!error) {
+		DRM_DEBUG_DRIVER("out of memory, not capturing error state\n");
+		return;
+	}
+
+	DRM_INFO("GPU crash dump saved to /sys/class/drm/card%d/error\n",
+		 dev->primary->index);
+	DRM_INFO("GPU hangs can indicate a bug anywhere in the entire gfx stack, including userspace.\n");
+	DRM_INFO("Please file a _new_ bug report on bugs.freedesktop.org against DRI -> DRM/Intel\n");
+	DRM_INFO("drm/i915 developers can then reassign to the right component if it's not a kernel issue.\n");
+	DRM_INFO("The gpu crash dump is required to analyze gpu hangs, so please always attach it.\n");
+
+	kref_init(&error->ref);
 
+	i915_capture_reg_state(dev_priv, error);
 	i915_gem_capture_buffers(dev_priv, error);
 	i915_gem_record_fences(dev, error);
 	i915_gem_record_rings(dev, error);