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path: root/kernel/drivers/gpu/drm/i915/intel_ringbuffer.h
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#
# Makefile for the Linux TCP/IP (INET6) layer.
#

obj-$(CONFIG_IPV6) += ipv6.o

ipv6-objs :=	af_inet6.o anycast.o ip6_output.o ip6_input.o addrconf.o \
		addrlabel.o \
		route.o ip6_fib.o ipv6_sockglue.o ndisc.o udp.o udplite.o \
		raw.o icmp.o mcast.o reassembly.o tcp_ipv6.o ping.o \
		exthdrs.o datagram.o ip6_flowlabel.o inet6_connection_sock.o

ipv6-offload :=	ip6_offload.o tcpv6_offload.o udp_offload.o exthdrs_offload.o

ipv6-$(CONFIG_SYSCTL) = sysctl_net_ipv6.o
ipv6-$(CONFIG_IPV6_MROUTE) += ip6mr.o

ipv6-$(CONFIG_XFRM) += xfrm6_policy.o xfrm6_state.o xfrm6_input.o \
	xfrm6_output.o xfrm6_protocol.o
ipv6-$(CONFIG_NETFILTER) += netfilter.o
ipv6-$(CONFIG_IPV6_MULTIPLE_TABLES) += fib6_rules.o
ipv6-$(CONFIG_PROC_FS) += proc.o
ipv6-$(CONFIG_SYN_COOKIES) += syncookies.o

ipv6-objs += $(ipv6-y)

obj-$(CONFIG_INET6_AH) += ah6.o
obj-$(CONFIG_INET6_ESP) += esp6.o
obj-$(CONFIG_INET6_IPCOMP) += ipcomp6.o
obj-$(CONFIG_INET6_XFRM_TUNNEL) += xfrm6_tunnel.o
obj-$(CONFIG_INET6_TUNNEL) += tunnel6.o
obj-$(CONFIG_INET6_XFRM_MODE_TRANSPORT) += xfrm6_mode_transport.o
obj-$(CONFIG_INET6_XFRM_MODE_TUNNEL) += xfrm6_mode_tunnel.o
obj-$(CONFIG_INET6_XFRM_MODE_ROUTEOPTIMIZATION) += xfrm6_mode_ro.o
obj-$(CONFIG_INET6_XFRM_MODE_BEET) += xfrm6_mode_beet.o
obj-$(CONFIG_IPV6_MIP6) += mip6.o
obj-$(CONFIG_NETFILTER)	+= netfilter/

obj-$(CONFIG_IPV6_VTI) += ip6_vti.o
obj-$(CONFIG_IPV6_SIT) += sit.o
obj-$(CONFIG_IPV6_TUNNEL) += ip6_tunnel.o
obj-$(CONFIG_IPV6_GRE) += ip6_gre.o

obj-y += addrconf_core.o exthdrs_core.o ip6_checksum.o ip6_icmp.o
obj-$(CONFIG_INET) += output_core.o protocol.o $(ipv6-offload)

obj-$(subst m,y,$(CONFIG_IPV6)) += inet6_hashtables.o

ifneq ($(CONFIG_IPV6),)
obj-$(CONFIG_NET_UDP_TUNNEL) += ip6_udp_tunnel.o
endif
#n456'>456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502
#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_ */