drm/i915: Classify the engines in class + instance

In such a way that vcs and vcs2 are just two different instances (0 and 1)
of the same engine class (VIDEO_DECODE_CLASS).

v2: Align the instance types (Tvrtko)

v3: Don't use enums for bspec-defined stuff (Michal)

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1491834873-9345-2-git-send-email-oscar.mateo@intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

drivers/gpu/drm/i915/i915_reg.h

@@ -85,6 +85,14 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
 #define VECS_HW		3
 #define VCS2_HW		4
 
+/* Engine class */
+
+#define RENDER_CLASS		0
+#define VIDEO_DECODE_CLASS	1
+#define VIDEO_ENHANCEMENT_CLASS	2
+#define COPY_ENGINE_CLASS	3
+#define OTHER_CLASS		4
+
 /* PCI config space */
 
 #define MCHBAR_I915 0x44

drivers/gpu/drm/i915/intel_engine_cs.c

@@ -30,6 +30,8 @@ static const struct engine_info {
 	const char *name;
 	unsigned int exec_id;
 	unsigned int hw_id;
+	u8 class;
+	u8 instance;
 	u32 mmio_base;
 	unsigned irq_shift;
 	int (*init_legacy)(struct intel_engine_cs *engine);
@@ -39,6 +41,8 @@ static const struct engine_info {
 		.name = "rcs",
 		.hw_id = RCS_HW,
 		.exec_id = I915_EXEC_RENDER,
+		.class = RENDER_CLASS,
+		.instance = 0,
 		.mmio_base = RENDER_RING_BASE,
 		.irq_shift = GEN8_RCS_IRQ_SHIFT,
 		.init_execlists = logical_render_ring_init,
@@ -48,6 +52,8 @@ static const struct engine_info {
 		.name = "bcs",
 		.hw_id = BCS_HW,
 		.exec_id = I915_EXEC_BLT,
+		.class = COPY_ENGINE_CLASS,
+		.instance = 0,
 		.mmio_base = BLT_RING_BASE,
 		.irq_shift = GEN8_BCS_IRQ_SHIFT,
 		.init_execlists = logical_xcs_ring_init,
@@ -57,6 +63,8 @@ static const struct engine_info {
 		.name = "vcs",
 		.hw_id = VCS_HW,
 		.exec_id = I915_EXEC_BSD,
+		.class = VIDEO_DECODE_CLASS,
+		.instance = 0,
 		.mmio_base = GEN6_BSD_RING_BASE,
 		.irq_shift = GEN8_VCS1_IRQ_SHIFT,
 		.init_execlists = logical_xcs_ring_init,
@@ -66,6 +74,8 @@ static const struct engine_info {
 		.name = "vcs2",
 		.hw_id = VCS2_HW,
 		.exec_id = I915_EXEC_BSD,
+		.class = VIDEO_DECODE_CLASS,
+		.instance = 1,
 		.mmio_base = GEN8_BSD2_RING_BASE,
 		.irq_shift = GEN8_VCS2_IRQ_SHIFT,
 		.init_execlists = logical_xcs_ring_init,
@@ -75,6 +85,8 @@ static const struct engine_info {
 		.name = "vecs",
 		.hw_id = VECS_HW,
 		.exec_id = I915_EXEC_VEBOX,
+		.class = VIDEO_ENHANCEMENT_CLASS,
+		.instance = 0,
 		.mmio_base = VEBOX_RING_BASE,
 		.irq_shift = GEN8_VECS_IRQ_SHIFT,
 		.init_execlists = logical_xcs_ring_init,
@@ -101,6 +113,8 @@ intel_engine_setup(struct drm_i915_private *dev_priv,
 	engine->hw_id = engine->guc_id = info->hw_id;
 	engine->mmio_base = info->mmio_base;
 	engine->irq_shift = info->irq_shift;
+	engine->class = info->class;
+	engine->instance = info->instance;
 
 	/* Nothing to do here, execute in order of dependencies */
 	engine->schedule = NULL;

drivers/gpu/drm/i915/intel_ringbuffer.h

@@ -193,6 +193,10 @@ struct intel_engine_cs {
 	enum intel_engine_id id;
 	unsigned int exec_id;
 	unsigned int hw_id;
+
+	u8 class;
+	u8 instance;
+
 	unsigned int guc_id;
 	u32		mmio_base;
 	unsigned int irq_shift;