drm/i915: Implement GPU reset for g33

g33 seems to sit somewhere between the 915/945/965 style and the
g4x style. The bits look like g4x, but we still need to do a full
reset including display.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_drv.c

@@ -881,8 +881,8 @@ int i915_reset(struct drm_device *dev)
 		if (INTEL_INFO(dev)->gen > 5)
 			intel_reset_gt_powersave(dev);
 
-		if ((IS_GEN3(dev) && !IS_G33(dev)) ||
-		    (IS_GEN4(dev) && !IS_G4X(dev))) {
+
+		if (IS_GEN3(dev) || (IS_GEN4(dev) && !IS_G4X(dev))) {
 			intel_runtime_pm_disable_interrupts(dev_priv);
 			intel_runtime_pm_enable_interrupts(dev_priv);
 

drivers/gpu/drm/i915/intel_uncore.c

@@ -1369,6 +1369,14 @@ static int g4x_reset_complete(struct drm_device *dev)
 	return (gdrst & GRDOM_RESET_ENABLE) == 0;
 }
 
+static int g33_do_reset(struct drm_device *dev)
+{
+	/* FIXME spec says to turn off all planes and wait 1 usec before reset */
+
+	pci_write_config_byte(dev->pdev, I915_GDRST, GRDOM_RESET_ENABLE);
+	return wait_for(g4x_reset_complete(dev), 500);
+}
+
 static int g4x_do_reset(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -1452,7 +1460,9 @@ int intel_gpu_reset(struct drm_device *dev)
 		return ironlake_do_reset(dev);
 	else if (IS_G4X(dev))
 		return g4x_do_reset(dev);
-	else if (IS_GEN4(dev) || (IS_GEN3(dev) &&  !IS_G33(dev)))
+	else if (IS_G33(dev))
+		return g33_do_reset(dev);
+	else if (INTEL_INFO(dev)->gen >= 3)
 		return i915_do_reset(dev);
 	else
 		return -ENODEV;