drm/i915: fix oops on single crtc devices.

(regression fix since fbdev/kms rework).

My fb rework didn't remember about the 84/65s.
Reported-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/i915/i915_drv.h

@@ -278,6 +278,7 @@ typedef struct drm_i915_private {
 	struct mem_block *agp_heap;
 	unsigned int sr01, adpa, ppcr, dvob, dvoc, lvds;
 	int vblank_pipe;
+	int num_pipe;
 
 	/* For hangcheck timer */
 #define DRM_I915_HANGCHECK_PERIOD 75 /* in jiffies */

drivers/gpu/drm/i915/intel_display.c

@@ -5470,7 +5470,6 @@ static void intel_init_display(struct drm_device *dev)
 void intel_modeset_init(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
-	int num_pipe;
 	int i;
 
 	drm_mode_config_init(dev);
@@ -5500,13 +5499,13 @@ void intel_modeset_init(struct drm_device *dev)
 		dev->mode_config.fb_base = pci_resource_start(dev->pdev, 0);
 
 	if (IS_MOBILE(dev) || IS_I9XX(dev))
-		num_pipe = 2;
+		dev_priv->num_pipe = 2;
 	else
-		num_pipe = 1;
+		dev_priv->num_pipe = 1;
 	DRM_DEBUG_KMS("%d display pipe%s available.\n",
-		  num_pipe, num_pipe > 1 ? "s" : "");
+		      dev_priv->num_pipe, dev_priv->num_pipe > 1 ? "s" : "");
 
-	for (i = 0; i < num_pipe; i++) {
+	for (i = 0; i < dev_priv->num_pipe; i++) {
 		intel_crtc_init(dev, i);
 	}
 

drivers/gpu/drm/i915/intel_fb.c

@@ -253,7 +253,7 @@ int intel_fbdev_init(struct drm_device *dev)
 	dev_priv->fbdev = ifbdev;
 	ifbdev->helper.funcs = &intel_fb_helper_funcs;
 
-	drm_fb_helper_init(dev, &ifbdev->helper, 2,
+	drm_fb_helper_init(dev, &ifbdev->helper, dev_priv->num_pipe,
 			   INTELFB_CONN_LIMIT);
 
 	drm_fb_helper_single_add_all_connectors(&ifbdev->helper);