drm/i915: Modify reset func to handle per engine resets

In full gpu reset we prime all engines and reset domains corresponding to
each engine. Per engine reset is just a special case of this process
wherein only a single engine is reset. This change is aimed to modify
relevant functions to achieve this. There are some other steps we carry out
in case of engine reset which are addressed in later patches.

Reset func now accepts a mask of all engines that need to be reset. Where
per engine resets are supported, error handler populates the mask
accordingly otherwise all engines are specified.

v2: ALL_ENGINES mask fixup, better for_each_ring_masked (Chris)
v3: Whitespace fixes (Chris)
v4: Rebase due to s/ring/engine

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1458143640-20563-1-git-send-email-mika.kuoppala@intel.com
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 8a10c4b..f2ab545 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1988,6 +1988,10 @@
 	for ((i__) = 0; (i__) < I915_NUM_ENGINES; (i__)++) \
 		for_each_if ((((ring__) = &(dev_priv__)->engine[(i__)]), intel_engine_initialized((ring__))))
 
+#define for_each_engine_masked(engine__, dev_priv__, mask__) \
+	for ((engine__) = &dev_priv->engine[0]; (engine__) < &dev_priv->engine[I915_NUM_ENGINES]; (engine__)++) \
+		for_each_if (intel_engine_flag((engine__)) & (mask__) && intel_engine_initialized((engine__)))
+
 enum hdmi_force_audio {
 	HDMI_AUDIO_OFF_DVI = -2,	/* no aux data for HDMI-DVI converter */
 	HDMI_AUDIO_OFF,			/* force turn off HDMI audio */
@@ -2570,6 +2574,8 @@
 #define BLT_RING		(1<<BCS)
 #define VEBOX_RING		(1<<VECS)
 #define BSD2_RING		(1<<VCS2)
+#define ALL_ENGINES		(~0)
+
 #define HAS_BSD(dev)		(INTEL_INFO(dev)->ring_mask & BSD_RING)
 #define HAS_BSD2(dev)		(INTEL_INFO(dev)->ring_mask & BSD2_RING)
 #define HAS_BLT(dev)		(INTEL_INFO(dev)->ring_mask & BLT_RING)
@@ -2698,7 +2704,7 @@
 extern long i915_compat_ioctl(struct file *filp, unsigned int cmd,
 			      unsigned long arg);
 #endif
-extern int intel_gpu_reset(struct drm_device *dev);
+extern int intel_gpu_reset(struct drm_device *dev, u32 engine_mask);
 extern bool intel_has_gpu_reset(struct drm_device *dev);
 extern int i915_reset(struct drm_device *dev);
 extern unsigned long i915_chipset_val(struct drm_i915_private *dev_priv);