File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
new file mode 100644
index 0000000..49fa41d
--- /dev/null
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -0,0 +1,502 @@
+#ifndef _INTEL_RINGBUFFER_H_
+#define _INTEL_RINGBUFFER_H_
+
+#include <linux/hashtable.h>
+#include "i915_gem_batch_pool.h"
+
+#define I915_CMD_HASH_ORDER 9
+
+/* Early gen2 devices have a cacheline of just 32 bytes, using 64 is overkill,
+ * but keeps the logic simple. Indeed, the whole purpose of this macro is just
+ * to give some inclination as to some of the magic values used in the various
+ * workarounds!
+ */
+#define CACHELINE_BYTES 64
+#define CACHELINE_DWORDS (CACHELINE_BYTES / sizeof(uint32_t))
+
+/*
+ * 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_MODE(ring) I915_READ(RING_MI_MODE((ring)->mmio_base))
+#define I915_WRITE_MODE(ring, val) I915_WRITE(RING_MI_MODE((ring)->mmio_base), val)
+
+/* seqno size is actually only a uint32, but since we plan to use MI_FLUSH_DW to
+ * do the writes, and that must have qw aligned offsets, simply pretend it's 8b.
+ */
+#define i915_semaphore_seqno_size sizeof(uint64_t)
+#define GEN8_SIGNAL_OFFSET(__ring, to)			     \
+	(i915_gem_obj_ggtt_offset(dev_priv->semaphore_obj) + \
+	((__ring)->id * I915_NUM_RINGS * i915_semaphore_seqno_size) +	\
+	(i915_semaphore_seqno_size * (to)))
+
+#define GEN8_WAIT_OFFSET(__ring, from)			     \
+	(i915_gem_obj_ggtt_offset(dev_priv->semaphore_obj) + \
+	((from) * I915_NUM_RINGS * i915_semaphore_seqno_size) + \
+	(i915_semaphore_seqno_size * (__ring)->id))
+
+#define GEN8_RING_SEMAPHORE_INIT do { \
+	if (!dev_priv->semaphore_obj) { \
+		break; \
+	} \
+	ring->semaphore.signal_ggtt[RCS] = GEN8_SIGNAL_OFFSET(ring, RCS); \
+	ring->semaphore.signal_ggtt[VCS] = GEN8_SIGNAL_OFFSET(ring, VCS); \
+	ring->semaphore.signal_ggtt[BCS] = GEN8_SIGNAL_OFFSET(ring, BCS); \
+	ring->semaphore.signal_ggtt[VECS] = GEN8_SIGNAL_OFFSET(ring, VECS); \
+	ring->semaphore.signal_ggtt[VCS2] = GEN8_SIGNAL_OFFSET(ring, VCS2); \
+	ring->semaphore.signal_ggtt[ring->id] = MI_SEMAPHORE_SYNC_INVALID; \
+	} while(0)
+
+enum intel_ring_hangcheck_action {
+	HANGCHECK_IDLE = 0,
+	HANGCHECK_WAIT,
+	HANGCHECK_ACTIVE,
+	HANGCHECK_ACTIVE_LOOP,
+	HANGCHECK_KICK,
+	HANGCHECK_HUNG,
+};
+
+#define HANGCHECK_SCORE_RING_HUNG 31
+
+struct intel_ring_hangcheck {
+	u64 acthd;
+	u64 max_acthd;
+	u32 seqno;
+	int score;
+	enum intel_ring_hangcheck_action action;
+	int deadlock;
+};
+
+struct intel_ringbuffer {
+	struct drm_i915_gem_object *obj;
+	void __iomem *virtual_start;
+
+	struct intel_engine_cs *ring;
+
+	u32 head;
+	u32 tail;
+	int space;
+	int size;
+	int effective_size;
+	int reserved_size;
+	int reserved_tail;
+	bool reserved_in_use;
+
+	/** 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;
+};
+
+struct	intel_context;
+struct drm_i915_reg_descriptor;
+
+/*
+ * we use a single page to load ctx workarounds so all of these
+ * values are referred in terms of dwords
+ *
+ * struct i915_wa_ctx_bb:
+ *  offset: specifies batch starting position, also helpful in case
+ *    if we want to have multiple batches at different offsets based on
+ *    some criteria. It is not a requirement at the moment but provides
+ *    an option for future use.
+ *  size: size of the batch in DWORDS
+ */
+struct  i915_ctx_workarounds {
+	struct i915_wa_ctx_bb {
+		u32 offset;
+		u32 size;
+	} indirect_ctx, per_ctx;
+	struct drm_i915_gem_object *obj;
+};
+
+struct  intel_engine_cs {
+	const char	*name;
+	enum intel_ring_id {
+		RCS = 0x0,
+		VCS,
+		BCS,
+		VECS,
+		VCS2
+	} id;
+#define I915_NUM_RINGS 5
+#define LAST_USER_RING (VECS + 1)
+	u32		mmio_base;
+	struct		drm_device *dev;
+	struct intel_ringbuffer *buffer;
+
+	/*
+	 * A pool of objects to use as shadow copies of client batch buffers
+	 * when the command parser is enabled. Prevents the client from
+	 * modifying the batch contents after software parsing.
+	 */
+	struct i915_gem_batch_pool batch_pool;
+
+	struct intel_hw_status_page status_page;
+	struct i915_ctx_workarounds wa_ctx;
+
+	unsigned irq_refcount; /* protected by dev_priv->irq_lock */
+	u32		irq_enable_mask;	/* bitmask to enable ring interrupt */
+	struct drm_i915_gem_request *trace_irq_req;
+	bool __must_check (*irq_get)(struct intel_engine_cs *ring);
+	void		(*irq_put)(struct intel_engine_cs *ring);
+
+	int		(*init_hw)(struct intel_engine_cs *ring);
+
+	int		(*init_context)(struct drm_i915_gem_request *req);
+
+	void		(*write_tail)(struct intel_engine_cs *ring,
+				      u32 value);
+	int __must_check (*flush)(struct drm_i915_gem_request *req,
+				  u32	invalidate_domains,
+				  u32	flush_domains);
+	int		(*add_request)(struct drm_i915_gem_request *req);
+	/* 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_engine_cs *ring,
+				     bool lazy_coherency);
+	void		(*set_seqno)(struct intel_engine_cs *ring,
+				     u32 seqno);
+	int		(*dispatch_execbuffer)(struct drm_i915_gem_request *req,
+					       u64 offset, u32 length,
+					       unsigned dispatch_flags);
+#define I915_DISPATCH_SECURE 0x1
+#define I915_DISPATCH_PINNED 0x2
+#define I915_DISPATCH_RS     0x4
+	void		(*cleanup)(struct intel_engine_cs *ring);
+
+	/* GEN8 signal/wait table - never trust comments!
+	 *	  signal to	signal to    signal to   signal to      signal to
+	 *	    RCS		   VCS          BCS        VECS		 VCS2
+	 *      --------------------------------------------------------------------
+	 *  RCS | NOP (0x00) | VCS (0x08) | BCS (0x10) | VECS (0x18) | VCS2 (0x20) |
+	 *	|-------------------------------------------------------------------
+	 *  VCS | RCS (0x28) | NOP (0x30) | BCS (0x38) | VECS (0x40) | VCS2 (0x48) |
+	 *	|-------------------------------------------------------------------
+	 *  BCS | RCS (0x50) | VCS (0x58) | NOP (0x60) | VECS (0x68) | VCS2 (0x70) |
+	 *	|-------------------------------------------------------------------
+	 * VECS | RCS (0x78) | VCS (0x80) | BCS (0x88) |  NOP (0x90) | VCS2 (0x98) |
+	 *	|-------------------------------------------------------------------
+	 * VCS2 | RCS (0xa0) | VCS (0xa8) | BCS (0xb0) | VECS (0xb8) | NOP  (0xc0) |
+	 *	|-------------------------------------------------------------------
+	 *
+	 * Generalization:
+	 *  f(x, y) := (x->id * NUM_RINGS * seqno_size) + (seqno_size * y->id)
+	 *  ie. transpose of g(x, y)
+	 *
+	 *	 sync from	sync from    sync from    sync from	sync from
+	 *	    RCS		   VCS          BCS        VECS		 VCS2
+	 *      --------------------------------------------------------------------
+	 *  RCS | NOP (0x00) | VCS (0x28) | BCS (0x50) | VECS (0x78) | VCS2 (0xa0) |
+	 *	|-------------------------------------------------------------------
+	 *  VCS | RCS (0x08) | NOP (0x30) | BCS (0x58) | VECS (0x80) | VCS2 (0xa8) |
+	 *	|-------------------------------------------------------------------
+	 *  BCS | RCS (0x10) | VCS (0x38) | NOP (0x60) | VECS (0x88) | VCS2 (0xb0) |
+	 *	|-------------------------------------------------------------------
+	 * VECS | RCS (0x18) | VCS (0x40) | BCS (0x68) |  NOP (0x90) | VCS2 (0xb8) |
+	 *	|-------------------------------------------------------------------
+	 * VCS2 | RCS (0x20) | VCS (0x48) | BCS (0x70) | VECS (0x98) |  NOP (0xc0) |
+	 *	|-------------------------------------------------------------------
+	 *
+	 * Generalization:
+	 *  g(x, y) := (y->id * NUM_RINGS * seqno_size) + (seqno_size * x->id)
+	 *  ie. transpose of f(x, y)
+	 */
+	struct {
+		u32	sync_seqno[I915_NUM_RINGS-1];
+
+		union {
+			struct {
+				/* our mbox written by others */
+				u32		wait[I915_NUM_RINGS];
+				/* mboxes this ring signals to */
+				u32		signal[I915_NUM_RINGS];
+			} mbox;
+			u64		signal_ggtt[I915_NUM_RINGS];
+		};
+
+		/* AKA wait() */
+		int	(*sync_to)(struct drm_i915_gem_request *to_req,
+				   struct intel_engine_cs *from,
+				   u32 seqno);
+		int	(*signal)(struct drm_i915_gem_request *signaller_req,
+				  /* num_dwords needed by caller */
+				  unsigned int num_dwords);
+	} semaphore;
+
+	/* Execlists */
+	spinlock_t execlist_lock;
+	struct list_head execlist_queue;
+	struct list_head execlist_retired_req_list;
+	u8 next_context_status_buffer;
+	u32             irq_keep_mask; /* bitmask for interrupts that should not be masked */
+	int		(*emit_request)(struct drm_i915_gem_request *request);
+	int		(*emit_flush)(struct drm_i915_gem_request *request,
+				      u32 invalidate_domains,
+				      u32 flush_domains);
+	int		(*emit_bb_start)(struct drm_i915_gem_request *req,
+					 u64 offset, unsigned dispatch_flags);
+
+	/**
+	 * List of objects currently involved in rendering from the
+	 * ringbuffer.
+	 *
+	 * Includes buffers having the contents of their GPU caches
+	 * flushed, not necessarily primitives.  last_read_req
+	 * 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;
+
+	/**
+	 * Seqno of request most recently submitted to request_list.
+	 * Used exclusively by hang checker to avoid grabbing lock while
+	 * inspecting request list.
+	 */
+	u32 last_submitted_seqno;
+
+	bool gpu_caches_dirty;
+
+	wait_queue_head_t irq_queue;
+
+	struct intel_context *default_context;
+	struct intel_context *last_context;
+
+	struct intel_ring_hangcheck hangcheck;
+
+	struct {
+		struct drm_i915_gem_object *obj;
+		u32 gtt_offset;
+		volatile u32 *cpu_page;
+	} scratch;
+
+	bool needs_cmd_parser;
+
+	/*
+	 * Table of commands the command parser needs to know about
+	 * for this ring.
+	 */
+	DECLARE_HASHTABLE(cmd_hash, I915_CMD_HASH_ORDER);
+
+	/*
+	 * Table of registers allowed in commands that read/write registers.
+	 */
+	const struct drm_i915_reg_descriptor *reg_table;
+	int reg_count;
+
+	/*
+	 * Table of registers allowed in commands that read/write registers, but
+	 * only from the DRM master.
+	 */
+	const struct drm_i915_reg_descriptor *master_reg_table;
+	int master_reg_count;
+
+	/*
+	 * Returns the bitmask for the length field of the specified command.
+	 * Return 0 for an unrecognized/invalid command.
+	 *
+	 * If the command parser finds an entry for a command in the ring's
+	 * cmd_tables, it gets the command's length based on the table entry.
+	 * If not, it calls this function to determine the per-ring length field
+	 * encoding for the command (i.e. certain opcode ranges use certain bits
+	 * to encode the command length in the header).
+	 */
+	u32 (*get_cmd_length_mask)(u32 cmd_header);
+};
+
+bool intel_ring_initialized(struct intel_engine_cs *ring);
+
+static inline unsigned
+intel_ring_flag(struct intel_engine_cs *ring)
+{
+	return 1 << ring->id;
+}
+
+static inline u32
+intel_ring_sync_index(struct intel_engine_cs *ring,
+		      struct intel_engine_cs *other)
+{
+	int idx;
+
+	/*
+	 * rcs -> 0 = vcs, 1 = bcs, 2 = vecs, 3 = vcs2;
+	 * vcs -> 0 = bcs, 1 = vecs, 2 = vcs2, 3 = rcs;
+	 * bcs -> 0 = vecs, 1 = vcs2. 2 = rcs, 3 = vcs;
+	 * vecs -> 0 = vcs2, 1 = rcs, 2 = vcs, 3 = bcs;
+	 * vcs2 -> 0 = rcs, 1 = vcs, 2 = bcs, 3 = vecs;
+	 */
+
+	idx = (other - ring) - 1;
+	if (idx < 0)
+		idx += I915_NUM_RINGS;
+
+	return idx;
+}
+
+static inline void
+intel_flush_status_page(struct intel_engine_cs *ring, int reg)
+{
+	drm_clflush_virt_range(&ring->status_page.page_addr[reg],
+			       sizeof(uint32_t));
+}
+
+static inline u32
+intel_read_status_page(struct intel_engine_cs *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_engine_cs *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)
+ * 0x20-0x2f: Reserved (Gen6+)
+ *
+ * The area from dword 0x30 to 0x3ff is available for driver usage.
+ */
+#define I915_GEM_HWS_INDEX		0x30
+#define I915_GEM_HWS_SCRATCH_INDEX	0x40
+#define I915_GEM_HWS_SCRATCH_ADDR (I915_GEM_HWS_SCRATCH_INDEX << MI_STORE_DWORD_INDEX_SHIFT)
+
+struct intel_ringbuffer *
+intel_engine_create_ringbuffer(struct intel_engine_cs *engine, int size);
+int intel_pin_and_map_ringbuffer_obj(struct drm_device *dev,
+				     struct intel_ringbuffer *ringbuf);
+void intel_unpin_ringbuffer_obj(struct intel_ringbuffer *ringbuf);
+void intel_ringbuffer_free(struct intel_ringbuffer *ring);
+
+void intel_stop_ring_buffer(struct intel_engine_cs *ring);
+void intel_cleanup_ring_buffer(struct intel_engine_cs *ring);
+
+int intel_ring_alloc_request_extras(struct drm_i915_gem_request *request);
+
+int __must_check intel_ring_begin(struct drm_i915_gem_request *req, int n);
+int __must_check intel_ring_cacheline_align(struct drm_i915_gem_request *req);
+static inline void intel_ring_emit(struct intel_engine_cs *ring,
+				   u32 data)
+{
+	struct intel_ringbuffer *ringbuf = ring->buffer;
+	iowrite32(data, ringbuf->virtual_start + ringbuf->tail);
+	ringbuf->tail += 4;
+}
+static inline void intel_ring_advance(struct intel_engine_cs *ring)
+{
+	struct intel_ringbuffer *ringbuf = ring->buffer;
+	ringbuf->tail &= ringbuf->size - 1;
+}
+int __intel_ring_space(int head, int tail, int size);
+void intel_ring_update_space(struct intel_ringbuffer *ringbuf);
+int intel_ring_space(struct intel_ringbuffer *ringbuf);
+bool intel_ring_stopped(struct intel_engine_cs *ring);
+
+int __must_check intel_ring_idle(struct intel_engine_cs *ring);
+void intel_ring_init_seqno(struct intel_engine_cs *ring, u32 seqno);
+int intel_ring_flush_all_caches(struct drm_i915_gem_request *req);
+int intel_ring_invalidate_all_caches(struct drm_i915_gem_request *req);
+
+void intel_fini_pipe_control(struct intel_engine_cs *ring);
+int intel_init_pipe_control(struct intel_engine_cs *ring);
+
+int intel_init_render_ring_buffer(struct drm_device *dev);
+int intel_init_bsd_ring_buffer(struct drm_device *dev);
+int intel_init_bsd2_ring_buffer(struct drm_device *dev);
+int intel_init_blt_ring_buffer(struct drm_device *dev);
+int intel_init_vebox_ring_buffer(struct drm_device *dev);
+
+u64 intel_ring_get_active_head(struct intel_engine_cs *ring);
+
+int init_workarounds_ring(struct intel_engine_cs *ring);
+
+static inline u32 intel_ring_get_tail(struct intel_ringbuffer *ringbuf)
+{
+	return ringbuf->tail;
+}
+
+/*
+ * Arbitrary size for largest possible 'add request' sequence. The code paths
+ * are complex and variable. Empirical measurement shows that the worst case
+ * is ILK at 136 words. Reserving too much is better than reserving too little
+ * as that allows for corner cases that might have been missed. So the figure
+ * has been rounded up to 160 words.
+ */
+#define MIN_SPACE_FOR_ADD_REQUEST	160
+
+/*
+ * Reserve space in the ring to guarantee that the i915_add_request() call
+ * will always have sufficient room to do its stuff. The request creation
+ * code calls this automatically.
+ */
+void intel_ring_reserved_space_reserve(struct intel_ringbuffer *ringbuf, int size);
+/* Cancel the reservation, e.g. because the request is being discarded. */
+void intel_ring_reserved_space_cancel(struct intel_ringbuffer *ringbuf);
+/* Use the reserved space - for use by i915_add_request() only. */
+void intel_ring_reserved_space_use(struct intel_ringbuffer *ringbuf);
+/* Finish with the reserved space - for use by i915_add_request() only. */
+void intel_ring_reserved_space_end(struct intel_ringbuffer *ringbuf);
+
+/* Legacy ringbuffer specific portion of reservation code: */
+int intel_ring_reserve_space(struct drm_i915_gem_request *request);
+
+#endif /* _INTEL_RINGBUFFER_H_ */