drivers/gpu/drm/i915/intel_ringbuffer.h

#ifndef _INTEL_RINGBUFFER_H_
#define _INTEL_RINGBUFFER_H_

struct  intel_hw_status_page {
	void		*page_addr;
	unsigned int	gfx_addr;
	struct		drm_gem_object *obj;
};

#define I915_READ_TAIL(ring) I915_READ(RING_TAIL(ring->mmio_base))
#define I915_WRITE_TAIL(ring, val) I915_WRITE(RING_TAIL(ring->mmio_base), val)
#define I915_READ_START(ring) I915_READ(RING_START(ring->mmio_base))
#define I915_WRITE_START(ring, val) I915_WRITE(RING_START(ring->mmio_base), val)
#define I915_READ_HEAD(ring) I915_READ(RING_HEAD(ring->mmio_base))
#define I915_WRITE_HEAD(ring, val) I915_WRITE(RING_HEAD(ring->mmio_base), val)
#define I915_READ_CTL(ring) I915_READ(RING_CTL(ring->mmio_base))
#define I915_WRITE_CTL(ring, val) I915_WRITE(RING_CTL(ring->mmio_base), val)

struct drm_i915_gem_execbuffer2;
struct  intel_ring_buffer {
	const char	*name;
	enum intel_ring_id {
		RING_RENDER = 0x1,
		RING_BSD = 0x2,
		RING_BLT = 0x4,
	} id;
	u32		mmio_base;
	unsigned long	size;
	void		*virtual_start;
	struct		drm_device *dev;
	struct		drm_gem_object *gem_object;

	unsigned int	head;
	unsigned int	tail;
	int		space;
	struct intel_hw_status_page status_page;

	u32		irq_gem_seqno;		/* last seq seem at irq time */
	u32		waiting_gem_seqno;
	int		user_irq_refcount;
	void		(*user_irq_get)(struct drm_device *dev,
			struct intel_ring_buffer *ring);
	void		(*user_irq_put)(struct drm_device *dev,
			struct intel_ring_buffer *ring);

	int		(*init)(struct drm_device *dev,
			struct intel_ring_buffer *ring);

	void		(*write_tail)(struct drm_device *dev,
				      struct intel_ring_buffer *ring,
				      u32 value);
	void		(*flush)(struct drm_device *dev,
			struct intel_ring_buffer *ring,
			u32	invalidate_domains,
			u32	flush_domains);
	u32		(*add_request)(struct drm_device *dev,
			struct intel_ring_buffer *ring,
			u32 flush_domains);
	u32		(*get_seqno)(struct drm_device *dev,
				     struct intel_ring_buffer *ring);
	int		(*dispatch_gem_execbuffer)(struct drm_device *dev,
			struct intel_ring_buffer *ring,
			struct drm_i915_gem_execbuffer2 *exec,
			struct drm_clip_rect *cliprects,
			uint64_t exec_offset);
	void		(*cleanup)(struct intel_ring_buffer *ring);

	/**
	 * List of objects currently involved in rendering from the
	 * ringbuffer.
	 *
	 * Includes buffers having the contents of their GPU caches
	 * flushed, not necessarily primitives.  last_rendering_seqno
	 * represents when the rendering involved will be completed.
	 *
	 * A reference is held on the buffer while on this list.
	 */
	struct list_head active_list;

	/**
	 * List of breadcrumbs associated with GPU requests currently
	 * outstanding.
	 */
	struct list_head request_list;

	/**
	 * List of objects currently pending a GPU write flush.
	 *
	 * All elements on this list will belong to either the
	 * active_list or flushing_list, last_rendering_seqno can
	 * be used to differentiate between the two elements.
	 */
	struct list_head gpu_write_list;

	/**
	 * Do we have some not yet emitted requests outstanding?
	 */
	bool outstanding_lazy_request;

	wait_queue_head_t irq_queue;
	drm_local_map_t map;

	void *private;
};

static inline u32
intel_read_status_page(struct intel_ring_buffer *ring,
		int reg)
{
	u32 *regs = ring->status_page.page_addr;
	return regs[reg];
}

int intel_init_ring_buffer(struct drm_device *dev,
			   struct intel_ring_buffer *ring);
void intel_cleanup_ring_buffer(struct drm_device *dev,
			       struct intel_ring_buffer *ring);
int intel_wait_ring_buffer(struct drm_device *dev,
			   struct intel_ring_buffer *ring, int n);
void intel_ring_begin(struct drm_device *dev,
		      struct intel_ring_buffer *ring, int n);

static inline void intel_ring_emit(struct drm_device *dev,
				   struct intel_ring_buffer *ring,
				   unsigned int data)
{
	unsigned int *virt = ring->virtual_start + ring->tail;
	*virt = data;
	ring->tail += 4;
}

void intel_ring_advance(struct drm_device *dev,
		struct intel_ring_buffer *ring);

u32 intel_ring_get_seqno(struct drm_device *dev,
		struct intel_ring_buffer *ring);

int intel_init_render_ring_buffer(struct drm_device *dev);
int intel_init_bsd_ring_buffer(struct drm_device *dev);
int intel_init_blt_ring_buffer(struct drm_device *dev);

u32 intel_ring_get_active_head(struct drm_device *dev,
			       struct intel_ring_buffer *ring);
void intel_ring_setup_status_page(struct drm_device *dev,
				  struct intel_ring_buffer *ring);

#endif /* _INTEL_RINGBUFFER_H_ */