drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h

/*
 * Copyright 2016 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors: Christian König
 */
#ifndef __AMDGPU_RING_H__
#define __AMDGPU_RING_H__

#include <drm/amdgpu_drm.h>
#include <drm/gpu_scheduler.h>
#include <drm/drm_print.h>
#include <drm/drm_suballoc.h>

struct amdgpu_device;
struct amdgpu_ring;
struct amdgpu_ib;
struct amdgpu_cs_parser;
struct amdgpu_job;
struct amdgpu_vm;

/* max number of rings */
#define AMDGPU_MAX_RINGS		149
#define AMDGPU_MAX_HWIP_RINGS		64
#define AMDGPU_MAX_GFX_RINGS		2
#define AMDGPU_MAX_SW_GFX_RINGS         2
#define AMDGPU_MAX_COMPUTE_RINGS	8
#define AMDGPU_MAX_VCE_RINGS		3
#define AMDGPU_MAX_UVD_ENC_RINGS	2
#define AMDGPU_MAX_VPE_RINGS		2

enum amdgpu_ring_priority_level {
	AMDGPU_RING_PRIO_0,
	AMDGPU_RING_PRIO_1,
	AMDGPU_RING_PRIO_DEFAULT = 1,
	AMDGPU_RING_PRIO_2,
	AMDGPU_RING_PRIO_MAX
};

/* some special values for the owner field */
#define AMDGPU_FENCE_OWNER_UNDEFINED	((void *)0ul)
#define AMDGPU_FENCE_OWNER_VM		((void *)1ul)
#define AMDGPU_FENCE_OWNER_KFD		((void *)2ul)

#define AMDGPU_FENCE_FLAG_64BIT         (1 << 0)
#define AMDGPU_FENCE_FLAG_INT           (1 << 1)
#define AMDGPU_FENCE_FLAG_TC_WB_ONLY    (1 << 2)

/* Ensure the execution in case of preemption or reset */
#define AMDGPU_FENCE_FLAG_EXEC          (1 << 3)

#define to_amdgpu_ring(s) container_of((s), struct amdgpu_ring, sched)

#define AMDGPU_IB_POOL_SIZE	(1024 * 1024)

enum amdgpu_ring_type {
	AMDGPU_RING_TYPE_GFX		= AMDGPU_HW_IP_GFX,
	AMDGPU_RING_TYPE_COMPUTE	= AMDGPU_HW_IP_COMPUTE,
	AMDGPU_RING_TYPE_SDMA		= AMDGPU_HW_IP_DMA,
	AMDGPU_RING_TYPE_UVD		= AMDGPU_HW_IP_UVD,
	AMDGPU_RING_TYPE_VCE		= AMDGPU_HW_IP_VCE,
	AMDGPU_RING_TYPE_UVD_ENC	= AMDGPU_HW_IP_UVD_ENC,
	AMDGPU_RING_TYPE_VCN_DEC	= AMDGPU_HW_IP_VCN_DEC,
	AMDGPU_RING_TYPE_VCN_ENC	= AMDGPU_HW_IP_VCN_ENC,
	AMDGPU_RING_TYPE_VCN_JPEG	= AMDGPU_HW_IP_VCN_JPEG,
	AMDGPU_RING_TYPE_VPE		= AMDGPU_HW_IP_VPE,
	AMDGPU_RING_TYPE_KIQ,
	AMDGPU_RING_TYPE_MES,
	AMDGPU_RING_TYPE_UMSCH_MM,
	AMDGPU_RING_TYPE_CPER,
	AMDGPU_RING_TYPE_MAX,
};

enum amdgpu_ib_pool_type {
	/* Normal submissions to the top of the pipeline. */
	AMDGPU_IB_POOL_DELAYED,
	/* Immediate submissions to the bottom of the pipeline. */
	AMDGPU_IB_POOL_IMMEDIATE,
	/* Direct submission to the ring buffer during init and reset. */
	AMDGPU_IB_POOL_DIRECT,

	AMDGPU_IB_POOL_MAX
};

struct amdgpu_ib {
	struct drm_suballoc		*sa_bo;
	uint32_t			length_dw;
	uint64_t			gpu_addr;
	uint32_t			*ptr;
	uint32_t			flags;
};

struct amdgpu_sched {
	u32				num_scheds;
	struct drm_gpu_scheduler	*sched[AMDGPU_MAX_HWIP_RINGS];
};

/*
 * Fences.
 */
struct amdgpu_fence_driver {
	uint64_t			gpu_addr;
	uint32_t			*cpu_addr;
	/* sync_seq is protected by ring emission lock */
	uint32_t			sync_seq;
	atomic_t			last_seq;
	bool				initialized;
	struct amdgpu_irq_src		*irq_src;
	unsigned			irq_type;
	struct timer_list		fallback_timer;
	unsigned			num_fences_mask;
	spinlock_t			lock;
	struct dma_fence		**fences;
};

/*
 * Fences mark an event in the GPUs pipeline and are used
 * for GPU/CPU synchronization.  When the fence is written,
 * it is expected that all buffers associated with that fence
 * are no longer in use by the associated ring on the GPU and
 * that the relevant GPU caches have been flushed.
 */

struct amdgpu_fence {
	struct dma_fence base;

	/* RB, DMA, etc. */
	struct amdgpu_ring		*ring;
	ktime_t				start_timestamp;

	/* location and size of the IB */
	u64				ib_wptr;
	unsigned int			ib_dw_size;
	unsigned int			skip_ib_dw_start_offset;
	unsigned int			skip_ib_dw_end_offset;
	/* fence context for resets */
	u64				context;
	/* idx for ring backups */
	unsigned int			backup_idx;
};

extern const struct drm_sched_backend_ops amdgpu_sched_ops;

void amdgpu_fence_driver_set_error(struct amdgpu_ring *ring, int error);
void amdgpu_fence_driver_force_completion(struct amdgpu_ring *ring,
					  struct dma_fence *timedout_fence);
void amdgpu_ring_set_fence_errors_and_reemit(struct amdgpu_ring *ring,
					     struct amdgpu_fence *guilty_fence);

int amdgpu_fence_driver_init_ring(struct amdgpu_ring *ring);
int amdgpu_fence_driver_start_ring(struct amdgpu_ring *ring,
				   struct amdgpu_irq_src *irq_src,
				   unsigned irq_type);
void amdgpu_fence_driver_hw_init(struct amdgpu_device *adev);
void amdgpu_fence_driver_hw_fini(struct amdgpu_device *adev);
int amdgpu_fence_driver_sw_init(struct amdgpu_device *adev);
void amdgpu_fence_driver_sw_fini(struct amdgpu_device *adev);
void amdgpu_fence_emit(struct amdgpu_ring *ring, struct amdgpu_fence *af,
		       unsigned int flags);
int amdgpu_fence_emit_polling(struct amdgpu_ring *ring, uint32_t *s,
			      uint32_t timeout);
bool amdgpu_fence_process(struct amdgpu_ring *ring);
int amdgpu_fence_wait_empty(struct amdgpu_ring *ring);
signed long amdgpu_fence_wait_polling(struct amdgpu_ring *ring,
				      uint32_t wait_seq,
				      signed long timeout);
unsigned amdgpu_fence_count_emitted(struct amdgpu_ring *ring);

void amdgpu_fence_driver_isr_toggle(struct amdgpu_device *adev, bool stop);

u64 amdgpu_fence_last_unsignaled_time_us(struct amdgpu_ring *ring);
void amdgpu_fence_update_start_timestamp(struct amdgpu_ring *ring, uint32_t seq,
					 ktime_t timestamp);

/*
 * Rings.
 */

/* provided by hw blocks that expose a ring buffer for commands */
struct amdgpu_ring_funcs {
	/**
	 * @type:
	 *
	 * GFX, Compute, SDMA, UVD, VCE, VCN, VPE, KIQ, MES, UMSCH, and CPER
	 * use ring buffers. The type field just identifies which component the
	 * ring buffer is associated with.
	 */
	enum amdgpu_ring_type	type;
	uint32_t		align_mask;

	/**
	 * @nop:
	 *
	 * Every block in the amdgpu has no-op instructions (e.g., GFX 10
	 * uses PACKET3(PACKET3_NOP, 0x3FFF), VCN 5 uses VCN_ENC_CMD_NO_OP,
	 * etc). This field receives the specific no-op for the component
	 * that initializes the ring.
	 */
	u32			nop;
	bool			support_64bit_ptrs;
	bool			no_user_fence;
	bool			secure_submission_supported;

	/**
	 * @extra_bytes:
	 *
	 * Optional extra space in bytes that is added to the ring size
	 * when allocating the BO that holds the contents of the ring.
	 * This space isn't used for command submission to the ring,
	 * but is just there to satisfy some hardware requirements or
	 * implement workarounds. It's up to the implementation of each
	 * specific ring to initialize this space.
	 */
	unsigned		extra_bytes;

	/* ring read/write ptr handling */
	u64 (*get_rptr)(struct amdgpu_ring *ring);
	u64 (*get_wptr)(struct amdgpu_ring *ring);
	void (*set_wptr)(struct amdgpu_ring *ring);
	/* validating and patching of IBs */
	int (*parse_cs)(struct amdgpu_cs_parser *p,
			struct amdgpu_job *job,
			struct amdgpu_ib *ib);
	int (*patch_cs_in_place)(struct amdgpu_cs_parser *p,
				 struct amdgpu_job *job,
				 struct amdgpu_ib *ib);
	/* constants to calculate how many DW are needed for an emit */
	unsigned emit_frame_size;
	unsigned emit_ib_size;
	/* command emit functions */
	void (*emit_ib)(struct amdgpu_ring *ring,
			struct amdgpu_job *job,
			struct amdgpu_ib *ib,
			uint32_t flags);
	void (*emit_fence)(struct amdgpu_ring *ring, uint64_t addr,
			   uint64_t seq, unsigned flags);
	void (*emit_pipeline_sync)(struct amdgpu_ring *ring);
	void (*emit_vm_flush)(struct amdgpu_ring *ring, unsigned vmid,
			      uint64_t pd_addr);
	void (*emit_hdp_flush)(struct amdgpu_ring *ring);
	void (*emit_gds_switch)(struct amdgpu_ring *ring, uint32_t vmid,
				uint32_t gds_base, uint32_t gds_size,
				uint32_t gws_base, uint32_t gws_size,
				uint32_t oa_base, uint32_t oa_size);
	/* testing functions */
	int (*test_ring)(struct amdgpu_ring *ring);
	int (*test_ib)(struct amdgpu_ring *ring, long timeout);
	/* insert NOP packets */
	void (*insert_nop)(struct amdgpu_ring *ring, uint32_t count);
	void (*insert_start)(struct amdgpu_ring *ring);
	void (*insert_end)(struct amdgpu_ring *ring);
	/* pad the indirect buffer to the necessary number of dw */
	void (*pad_ib)(struct amdgpu_ring *ring, struct amdgpu_ib *ib);
	unsigned (*init_cond_exec)(struct amdgpu_ring *ring, uint64_t addr);
	/* note usage for clock and power gating */
	void (*begin_use)(struct amdgpu_ring *ring);
	void (*end_use)(struct amdgpu_ring *ring);
	void (*emit_switch_buffer) (struct amdgpu_ring *ring);
	void (*emit_cntxcntl) (struct amdgpu_ring *ring, uint32_t flags);
	void (*emit_gfx_shadow)(struct amdgpu_ring *ring, u64 shadow_va, u64 csa_va,
				u64 gds_va, bool init_shadow, int vmid);
	void (*emit_rreg)(struct amdgpu_ring *ring, uint32_t reg,
			  uint32_t reg_val_offs);
	void (*emit_wreg)(struct amdgpu_ring *ring, uint32_t reg, uint32_t val);
	void (*emit_reg_wait)(struct amdgpu_ring *ring, uint32_t reg,
			      uint32_t val, uint32_t mask);
	void (*emit_reg_write_reg_wait)(struct amdgpu_ring *ring,
					uint32_t reg0, uint32_t reg1,
					uint32_t ref, uint32_t mask);
	void (*emit_frame_cntl)(struct amdgpu_ring *ring, bool start,
				bool secure);
	/* Try to soft recover the ring to make the fence signal */
	void (*soft_recovery)(struct amdgpu_ring *ring, unsigned vmid);
	int (*preempt_ib)(struct amdgpu_ring *ring);
	void (*emit_mem_sync)(struct amdgpu_ring *ring);
	void (*emit_wave_limit)(struct amdgpu_ring *ring, bool enable);
	void (*patch_cntl)(struct amdgpu_ring *ring, unsigned offset);
	void (*patch_ce)(struct amdgpu_ring *ring, unsigned offset);
	void (*patch_de)(struct amdgpu_ring *ring, unsigned offset);
	int (*reset)(struct amdgpu_ring *ring, unsigned int vmid,
		     struct amdgpu_fence *timedout_fence);
	void (*emit_cleaner_shader)(struct amdgpu_ring *ring);
};

/**
 * amdgpu_ring - Holds ring information
 */
struct amdgpu_ring {
	struct amdgpu_device		*adev;
	const struct amdgpu_ring_funcs	*funcs;
	struct amdgpu_fence_driver	fence_drv;
	struct drm_gpu_scheduler	sched;

	struct amdgpu_bo	*ring_obj;
	uint32_t		*ring;
	/* backups for resets */
	uint32_t		*ring_backup;
	unsigned int		ring_backup_entries_to_copy;
	bool			reemit;
	unsigned		rptr_offs;
	u64			rptr_gpu_addr;
	u32			*rptr_cpu_addr;

	/**
	 * @wptr:
	 *
	 * This is part of the Ring buffer implementation and represents the
	 * write pointer. The wptr determines where the host has written.
	 */
	u64			wptr;

	/**
	 * @wptr_old:
	 *
	 * Before update wptr with the new value, usually the old value is
	 * stored in the wptr_old.
	 */
	u64			wptr_old;
	unsigned		ring_size;

	/**
	 * @max_dw:
	 *
	 * Maximum number of DWords for ring allocation. This information is
	 * provided at the ring initialization time, and each IP block can
	 * specify a specific value. Check places that invoke
	 * amdgpu_ring_init() to see the maximum size per block.
	 */
	unsigned		max_dw;

	/**
	 * @count_dw:
	 *
	 * This value starts with the maximum amount of DWords supported by the
	 * ring. This value is updated based on the ring manipulation.
	 */
	int			count_dw;
	uint64_t		gpu_addr;

	/**
	 * @ptr_mask:
	 *
	 * Some IPs provide support for 64-bit pointers and others for 32-bit
	 * only; this behavior is component-specific and defined by the field
	 * support_64bit_ptr. If the IP block supports 64-bits, the mask
	 * 0xffffffffffffffff is set; otherwise, this value assumes buf_mask.
	 * Notice that this field is used to keep wptr under a valid range.
	 */
	uint64_t		ptr_mask;

	/**
	 * @buf_mask:
	 *
	 * Buffer mask is a value used to keep wptr count under its
	 * thresholding. Buffer mask initialized during the ring buffer
	 * initialization time, and it is defined as (ring_size / 4) -1.
	 */
	uint32_t		buf_mask;
	u32			idx;
	u32			xcc_id;
	u32			xcp_id;
	u32			me;
	u32			pipe;
	u32			queue;
	struct amdgpu_bo	*mqd_obj;
	uint64_t                mqd_gpu_addr;
	void                    *mqd_ptr;
	unsigned                mqd_size;
	uint64_t                eop_gpu_addr;
	u32			doorbell_index;
	bool			use_doorbell;
	bool			use_pollmem;
	unsigned		wptr_offs;
	u64			wptr_gpu_addr;

	/**
	 * @wptr_cpu_addr:
	 *
	 * This is the CPU address pointer in the writeback slot. This is used
	 * to commit changes to the GPU.
	 */
	u32			*wptr_cpu_addr;
	unsigned		fence_offs;
	u64			fence_gpu_addr;
	u32			*fence_cpu_addr;
	uint64_t		current_ctx;
	char			name[16];
	u32                     trail_seq;
	unsigned		trail_fence_offs;
	u64			trail_fence_gpu_addr;
	u32			*trail_fence_cpu_addr;
	unsigned		cond_exe_offs;
	u64			cond_exe_gpu_addr;
	u32			*cond_exe_cpu_addr;
	unsigned int		set_q_mode_offs;
	u32			*set_q_mode_ptr;
	u64			set_q_mode_token;
	unsigned		vm_hub;
	unsigned		vm_inv_eng;
	struct dma_fence	*vmid_wait;
	bool			has_compute_vm_bug;
	bool			no_scheduler;
	bool			no_user_submission;
	int			hw_prio;
	unsigned 		num_hw_submission;
	atomic_t		*sched_score;

	bool            is_sw_ring;
	unsigned int    entry_index;
	/* store the cached rptr to restore after reset */
	uint64_t cached_rptr;
};

#define amdgpu_ring_parse_cs(r, p, job, ib) ((r)->funcs->parse_cs((p), (job), (ib)))
#define amdgpu_ring_patch_cs_in_place(r, p, job, ib) ((r)->funcs->patch_cs_in_place((p), (job), (ib)))
#define amdgpu_ring_test_ring(r) (r)->funcs->test_ring((r))
#define amdgpu_ring_test_ib(r, t) ((r)->funcs->test_ib ? (r)->funcs->test_ib((r), (t)) : 0)
#define amdgpu_ring_get_rptr(r) (r)->funcs->get_rptr((r))
#define amdgpu_ring_get_wptr(r) (r)->funcs->get_wptr((r))
#define amdgpu_ring_set_wptr(r) (r)->funcs->set_wptr((r))
#define amdgpu_ring_emit_ib(r, job, ib, flags) ((r)->funcs->emit_ib((r), (job), (ib), (flags)))
#define amdgpu_ring_emit_pipeline_sync(r) (r)->funcs->emit_pipeline_sync((r))
#define amdgpu_ring_emit_vm_flush(r, vmid, addr) (r)->funcs->emit_vm_flush((r), (vmid), (addr))
#define amdgpu_ring_emit_fence(r, addr, seq, flags) (r)->funcs->emit_fence((r), (addr), (seq), (flags))
#define amdgpu_ring_emit_gds_switch(r, v, db, ds, wb, ws, ab, as) (r)->funcs->emit_gds_switch((r), (v), (db), (ds), (wb), (ws), (ab), (as))
#define amdgpu_ring_emit_hdp_flush(r) (r)->funcs->emit_hdp_flush((r))
#define amdgpu_ring_emit_switch_buffer(r) (r)->funcs->emit_switch_buffer((r))
#define amdgpu_ring_emit_cntxcntl(r, d) (r)->funcs->emit_cntxcntl((r), (d))
#define amdgpu_ring_emit_gfx_shadow(r, s, c, g, i, v) ((r)->funcs->emit_gfx_shadow((r), (s), (c), (g), (i), (v)))
#define amdgpu_ring_emit_rreg(r, d, o) (r)->funcs->emit_rreg((r), (d), (o))
#define amdgpu_ring_emit_wreg(r, d, v) (r)->funcs->emit_wreg((r), (d), (v))
#define amdgpu_ring_emit_reg_wait(r, d, v, m) (r)->funcs->emit_reg_wait((r), (d), (v), (m))
#define amdgpu_ring_emit_reg_write_reg_wait(r, d0, d1, v, m) (r)->funcs->emit_reg_write_reg_wait((r), (d0), (d1), (v), (m))
#define amdgpu_ring_emit_frame_cntl(r, b, s) (r)->funcs->emit_frame_cntl((r), (b), (s))
#define amdgpu_ring_pad_ib(r, ib) ((r)->funcs->pad_ib((r), (ib)))
#define amdgpu_ring_init_cond_exec(r, a) (r)->funcs->init_cond_exec((r), (a))
#define amdgpu_ring_preempt_ib(r) (r)->funcs->preempt_ib(r)
#define amdgpu_ring_patch_cntl(r, o) ((r)->funcs->patch_cntl((r), (o)))
#define amdgpu_ring_patch_ce(r, o) ((r)->funcs->patch_ce((r), (o)))
#define amdgpu_ring_patch_de(r, o) ((r)->funcs->patch_de((r), (o)))
#define amdgpu_ring_reset(r, v, f) (r)->funcs->reset((r), (v), (f))

unsigned int amdgpu_ring_max_ibs(enum amdgpu_ring_type type);
int amdgpu_ring_alloc(struct amdgpu_ring *ring, unsigned ndw);
void amdgpu_ring_ib_begin(struct amdgpu_ring *ring);
void amdgpu_ring_ib_end(struct amdgpu_ring *ring);
void amdgpu_ring_ib_on_emit_cntl(struct amdgpu_ring *ring);
void amdgpu_ring_ib_on_emit_ce(struct amdgpu_ring *ring);
void amdgpu_ring_ib_on_emit_de(struct amdgpu_ring *ring);

void amdgpu_ring_insert_nop(struct amdgpu_ring *ring, uint32_t count);
void amdgpu_ring_generic_pad_ib(struct amdgpu_ring *ring, struct amdgpu_ib *ib);
void amdgpu_ring_commit(struct amdgpu_ring *ring);
void amdgpu_ring_undo(struct amdgpu_ring *ring);
int amdgpu_ring_init(struct amdgpu_device *adev, struct amdgpu_ring *ring,
		     unsigned int max_dw, struct amdgpu_irq_src *irq_src,
		     unsigned int irq_type, unsigned int hw_prio,
		     atomic_t *sched_score);
void amdgpu_ring_fini(struct amdgpu_ring *ring);
void amdgpu_ring_emit_reg_write_reg_wait_helper(struct amdgpu_ring *ring,
						uint32_t reg0, uint32_t val0,
						uint32_t reg1, uint32_t val1);
bool amdgpu_ring_soft_recovery(struct amdgpu_ring *ring, unsigned int vmid,
			       struct dma_fence *fence);

static inline void amdgpu_ring_set_preempt_cond_exec(struct amdgpu_ring *ring,
							bool cond_exec)
{
	*ring->cond_exe_cpu_addr = cond_exec;
}

static inline void amdgpu_ring_clear_ring(struct amdgpu_ring *ring)
{
	memset32(ring->ring, ring->funcs->nop, ring->buf_mask + 1);
}

static inline void amdgpu_ring_write(struct amdgpu_ring *ring, uint32_t v)
{
	ring->ring[ring->wptr++ & ring->buf_mask] = v;
	ring->wptr &= ring->ptr_mask;
	ring->count_dw--;
}

static inline void amdgpu_ring_write_multiple(struct amdgpu_ring *ring,
					      void *src, int count_dw)
{
	unsigned occupied, chunk1, chunk2;

	occupied = ring->wptr & ring->buf_mask;
	chunk1 = ring->buf_mask + 1 - occupied;
	chunk1 = (chunk1 >= count_dw) ? count_dw : chunk1;
	chunk2 = count_dw - chunk1;
	chunk1 <<= 2;
	chunk2 <<= 2;

	if (chunk1)
		memcpy(&ring->ring[occupied], src, chunk1);

	if (chunk2) {
		src += chunk1;
		memcpy(ring->ring, src, chunk2);
	}

	ring->wptr += count_dw;
	ring->wptr &= ring->ptr_mask;
	ring->count_dw -= count_dw;
}

static inline unsigned int amdgpu_ring_get_dw_distance(struct amdgpu_ring *ring,
						       u64 start_wptr, u64 end_wptr)
{
	unsigned int start = start_wptr & ring->buf_mask;
	unsigned int end = end_wptr & ring->buf_mask;

	if (end < start)
		end += ring->ring_size >> 2;
	return end - start;
}

/**
 * amdgpu_ring_patch_cond_exec - patch dw count of conditional execute
 * @ring: amdgpu_ring structure
 * @offset: offset returned by amdgpu_ring_init_cond_exec
 *
 * Calculate the dw count and patch it into a cond_exec command.
 */
static inline void amdgpu_ring_patch_cond_exec(struct amdgpu_ring *ring,
					       unsigned int offset)
{
	if (!ring->funcs->init_cond_exec)
		return;

	WARN_ON(offset > ring->buf_mask);
	WARN_ON(ring->ring[offset] != 0);

	ring->ring[offset] = amdgpu_ring_get_dw_distance(ring, offset, ring->wptr - 1);
}

int amdgpu_ring_test_helper(struct amdgpu_ring *ring);

void amdgpu_debugfs_ring_init(struct amdgpu_device *adev,
			      struct amdgpu_ring *ring);

int amdgpu_ring_init_mqd(struct amdgpu_ring *ring);

static inline u32 amdgpu_ib_get_value(struct amdgpu_ib *ib, uint32_t idx)
{
	if (idx < ib->length_dw)
		return ib->ptr[idx];
	return 0;
}

static inline void amdgpu_ib_set_value(struct amdgpu_ib *ib, uint32_t idx,
				       uint32_t value)
{
	if (idx < ib->length_dw)
		ib->ptr[idx] = value;
}

int amdgpu_ib_get(struct amdgpu_device *adev, struct amdgpu_vm *vm,
		  unsigned size,
		  enum amdgpu_ib_pool_type pool,
		  struct amdgpu_ib *ib);
void amdgpu_ib_free(struct amdgpu_ib *ib, struct dma_fence *f);
int amdgpu_ib_schedule(struct amdgpu_ring *ring, unsigned num_ibs,
		       struct amdgpu_ib *ibs, struct amdgpu_job *job,
		       struct dma_fence **f);
int amdgpu_ib_pool_init(struct amdgpu_device *adev);
void amdgpu_ib_pool_fini(struct amdgpu_device *adev);
int amdgpu_ib_ring_tests(struct amdgpu_device *adev);
bool amdgpu_ring_sched_ready(struct amdgpu_ring *ring);
void amdgpu_ring_backup_unprocessed_commands(struct amdgpu_ring *ring,
					     struct amdgpu_fence *guilty_fence);
void amdgpu_ring_reset_helper_begin(struct amdgpu_ring *ring,
				    struct amdgpu_fence *guilty_fence);
int amdgpu_ring_reset_helper_end(struct amdgpu_ring *ring,
				 struct amdgpu_fence *guilty_fence);
bool amdgpu_ring_is_reset_type_supported(struct amdgpu_ring *ring,
					 u32 reset_type);
#endif