#ifndef _INTEL_RINGBUFFER_H_
#define _INTEL_RINGBUFFER_H_

/*
 * Gen2 BSpec "1. Programming Environment" / 1.4.4.6 "Ring Buffer Use"
 * Gen3 BSpec "vol1c Memory Interface Functions" / 2.3.4.5 "Ring Buffer Use"
 * Gen4+ BSpec "vol1c Memory Interface and Command Stream" / 5.3.4.5 "Ring Buffer Use"
 *
 * "If the Ring Buffer Head Pointer and the Tail Pointer are on the same
 * cacheline, the Head Pointer must not be greater than the Tail
 * Pointer."
 */
#define I915_RING_FREE_SPACE 64

struct  intel_hw_status_page {
        u32             *page_addr;
        unsigned int    gfx_addr;
        struct          drm_i915_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)

#define I915_READ_IMR(ring) I915_READ(RING_IMR((ring)->mmio_base))
#define I915_WRITE_IMR(ring, val) I915_WRITE(RING_IMR((ring)->mmio_base), val)

#define I915_READ_NOPID(ring) I915_READ(RING_NOPID((ring)->mmio_base))
#define I915_READ_SYNC_0(ring) I915_READ(RING_SYNC_0((ring)->mmio_base))
#define I915_READ_SYNC_1(ring) I915_READ(RING_SYNC_1((ring)->mmio_base))

struct  intel_ring_buffer {
        const char      *name;
        enum intel_ring_id {
                RCS = 0x0,
                VCS,
                BCS,
        } id;
#define I915_NUM_RINGS 3
        u32             mmio_base;
        void            __iomem *virtual_start;
        struct          drm_device *dev;
        struct          drm_i915_gem_object *obj;

        u32             head;
        u32             tail;
        int             space;
        int             size;
        int             effective_size;
        struct intel_hw_status_page status_page;

        /** We track the position of the requests in the ring buffer, and
         * when each is retired we increment last_retired_head as the GPU
         * must have finished processing the request and so we know we
         * can advance the ringbuffer up to that position.
         *
         * last_retired_head is set to -1 after the value is consumed so
         * we can detect new retirements.
         */
        u32             last_retired_head;

        u32             irq_refcount;           /* protected by dev_priv->irq_lock */
        u32             irq_enable_mask;        /* bitmask to enable ring interrupt */
        u32             trace_irq_seqno;
        u32             sync_seqno[I915_NUM_RINGS-1];
        bool __must_check (*irq_get)(struct intel_ring_buffer *ring);
        void            (*irq_put)(struct intel_ring_buffer *ring);

        int             (*init)(struct intel_ring_buffer *ring);

        void            (*write_tail)(struct intel_ring_buffer *ring,
                                      u32 value);
        int __must_check (*flush)(struct intel_ring_buffer *ring,
                                  u32   invalidate_domains,
                                  u32   flush_domains);
        int             (*add_request)(struct intel_ring_buffer *ring);
        /* Some chipsets are not quite as coherent as advertised and need
         * an expensive kick to force a true read of the up-to-date seqno.
         * However, the up-to-date seqno is not always required and the last
         * seen value is good enough. Note that the seqno will always be
         * monotonic, even if not coherent.
         */
        u32             (*get_seqno)(struct intel_ring_buffer *ring,
                                     bool lazy_coherency);
        void            (*set_seqno)(struct intel_ring_buffer *ring,
                                     u32 seqno);
        int             (*dispatch_execbuffer)(struct intel_ring_buffer *ring,
                                               u32 offset, u32 length,
                                               unsigned flags);
#define I915_DISPATCH_SECURE 0x1
#define I915_DISPATCH_PINNED 0x2
        void            (*cleanup)(struct intel_ring_buffer *ring);
        int             (*sync_to)(struct intel_ring_buffer *ring,
                                   struct intel_ring_buffer *to,
                                   u32 seqno);

        u32             semaphore_register[3]; /*our mbox written by others */
        u32             signal_mbox[2]; /* mboxes this ring signals to */
        /**
         * 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;

        /**
         * Do we have some not yet emitted requests outstanding?
         */
        u32 outstanding_lazy_request;
        bool gpu_caches_dirty;

        wait_queue_head_t irq_queue;

        /**
         * Do an explicit TLB flush before MI_SET_CONTEXT
         */
        bool itlb_before_ctx_switch;
        struct i915_hw_context *default_context;
        struct drm_i915_gem_object *last_context_obj;

        void *private;
};

static inline bool
intel_ring_initialized(struct intel_ring_buffer *ring)
{
        return ring->obj != NULL;
}

static inline unsigned
intel_ring_flag(struct intel_ring_buffer *ring)
{
        return 1 << ring->id;
}

static inline u32
intel_ring_sync_index(struct intel_ring_buffer *ring,
                      struct intel_ring_buffer *other)
{
        int idx;

        /*
         * cs -> 0 = vcs, 1 = bcs
         * vcs -> 0 = bcs, 1 = cs,
         * bcs -> 0 = cs, 1 = vcs.
         */

        idx = (other - ring) - 1;
        if (idx < 0)
                idx += I915_NUM_RINGS;

        return idx;
}

static inline u32
intel_read_status_page(struct intel_ring_buffer *ring,
                       int reg)
{
        /* Ensure that the compiler doesn't optimize away the load. */
        barrier();
        return ring->status_page.page_addr[reg];
}

static inline void
intel_write_status_page(struct intel_ring_buffer *ring,
                        int reg, u32 value)
{
        ring->status_page.page_addr[reg] = value;
}

/**
 * Reads a dword out of the status page, which is written to from the command
 * queue by automatic updates, MI_REPORT_HEAD, MI_STORE_DATA_INDEX, or
 * MI_STORE_DATA_IMM.
 *
 * The following dwords have a reserved meaning:
 * 0x00: ISR copy, updated when an ISR bit not set in the HWSTAM changes.
 * 0x04: ring 0 head pointer
 * 0x05: ring 1 head pointer (915-class)
 * 0x06: ring 2 head pointer (915-class)
 * 0x10-0x1b: Context status DWords (GM45)
 * 0x1f: Last written status offset. (GM45)
 *
 * The area from dword 0x20 to 0x3ff is available for driver usage.
 */
#define I915_GEM_HWS_INDEX              0x20
#define I915_GEM_HWS_SCRATCH_INDEX      0x30
#define I915_GEM_HWS_SCRATCH_ADDR (I915_GEM_HWS_SCRATCH_INDEX << MI_STORE_DWORD_INDEX_SHIFT)

void intel_cleanup_ring_buffer(struct intel_ring_buffer *ring);

int __must_check intel_ring_begin(struct intel_ring_buffer *ring, int n);
static inline void intel_ring_emit(struct intel_ring_buffer *ring,
                                   u32 data)
{
        iowrite32(data, ring->virtual_start + ring->tail);
        ring->tail += 4;
}
void intel_ring_advance(struct intel_ring_buffer *ring);
int __must_check intel_ring_idle(struct intel_ring_buffer *ring);
void intel_ring_init_seqno(struct intel_ring_buffer *ring, u32 seqno);
int intel_ring_flush_all_caches(struct intel_ring_buffer *ring);
int intel_ring_invalidate_all_caches(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 intel_ring_buffer *ring);
void intel_ring_setup_status_page(struct intel_ring_buffer *ring);

static inline u32 intel_ring_get_tail(struct intel_ring_buffer *ring)
{
        return ring->tail;
}

static inline u32 intel_ring_get_seqno(struct intel_ring_buffer *ring)
{
        BUG_ON(ring->outstanding_lazy_request == 0);
        return ring->outstanding_lazy_request;
}

static inline void i915_trace_irq_get(struct intel_ring_buffer *ring, u32 seqno)
{
        if (ring->trace_irq_seqno == 0 && ring->irq_get(ring))
                ring->trace_irq_seqno = seqno;
}

/* DRI warts */
int intel_render_ring_init_dri(struct drm_device *dev, u64 start, u32 size);

#endif /* _INTEL_RINGBUFFER_H_ */