/* SPDX-License-Identifier: MIT */
/*
 * Copyright © 2019 Intel Corporation
 */

#ifndef __INTEL_CONTEXT_TYPES__
#define __INTEL_CONTEXT_TYPES__

#include <linux/average.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/types.h>

#include "i915_active_types.h"
#include "i915_sw_fence.h"
#include "intel_engine_types.h"
#include "intel_sseu.h"
#include "intel_wakeref.h"

#include "uc/intel_guc_fwif.h"

#define CONTEXT_REDZONE POISON_INUSE
DECLARE_EWMA(runtime, 3, 8);

struct i915_gem_context;
struct i915_gem_ww_ctx;
struct i915_vma;
struct intel_breadcrumbs;
struct intel_context;
struct intel_ring;

struct intel_context_ops {
        unsigned long flags;
#define COPS_HAS_INFLIGHT_BIT 0
#define COPS_HAS_INFLIGHT BIT(COPS_HAS_INFLIGHT_BIT)

#define COPS_RUNTIME_CYCLES_BIT 1
#define COPS_RUNTIME_CYCLES BIT(COPS_RUNTIME_CYCLES_BIT)

        int (*alloc)(struct intel_context *ce);

        void (*revoke)(struct intel_context *ce, struct i915_request *rq,
                       unsigned int preempt_timeout_ms);

        void (*close)(struct intel_context *ce);

        int (*pre_pin)(struct intel_context *ce, struct i915_gem_ww_ctx *ww, void **vaddr);
        int (*pin)(struct intel_context *ce, void *vaddr);
        void (*unpin)(struct intel_context *ce);
        void (*post_unpin)(struct intel_context *ce);

        void (*cancel_request)(struct intel_context *ce,
                               struct i915_request *rq);

        void (*enter)(struct intel_context *ce);
        void (*exit)(struct intel_context *ce);

        void (*sched_disable)(struct intel_context *ce);

        void (*update_stats)(struct intel_context *ce);

        void (*reset)(struct intel_context *ce);
        void (*destroy)(struct kref *kref);

        /* virtual/parallel engine/context interface */
        struct intel_context *(*create_virtual)(struct intel_engine_cs **engine,
                                                unsigned int count,
                                                unsigned long flags);
        struct intel_context *(*create_parallel)(struct intel_engine_cs **engines,
                                                 unsigned int num_siblings,
                                                 unsigned int width);
        struct intel_engine_cs *(*get_sibling)(struct intel_engine_cs *engine,
                                               unsigned int sibling);
};

struct intel_context {
        /*
         * Note: Some fields may be accessed under RCU.
         *
         * Unless otherwise noted a field can safely be assumed to be protected
         * by strong reference counting.
         */
        union {
                struct kref ref; /* no kref_get_unless_zero()! */
                struct rcu_head rcu;
        };

        struct intel_engine_cs *engine;
        struct intel_engine_cs *inflight;
#define __intel_context_inflight(engine) ptr_mask_bits(engine, 3)
#define __intel_context_inflight_count(engine) ptr_unmask_bits(engine, 3)
#define intel_context_inflight(ce) \
        __intel_context_inflight(READ_ONCE((ce)->inflight))
#define intel_context_inflight_count(ce) \
        __intel_context_inflight_count(READ_ONCE((ce)->inflight))

        struct i915_address_space *vm;
        struct i915_gem_context __rcu *gem_context;

        struct file *default_state;

        /*
         * @signal_lock protects the list of requests that need signaling,
         * @signals. While there are any requests that need signaling,
         * we add the context to the breadcrumbs worker, and remove it
         * upon completion/cancellation of the last request.
         */
        struct list_head signal_link; /* Accessed under RCU */
        struct list_head signals; /* Guarded by signal_lock */
        spinlock_t signal_lock; /* protects signals, the list of requests */

        struct i915_vma *state;
        u32 ring_size;
        struct intel_ring *ring;
        struct intel_timeline *timeline;
        intel_wakeref_t wakeref;

        unsigned long flags;
#define CONTEXT_BARRIER_BIT             0
#define CONTEXT_ALLOC_BIT               1
#define CONTEXT_INIT_BIT                2
#define CONTEXT_VALID_BIT               3
#define CONTEXT_CLOSED_BIT              4
#define CONTEXT_USE_SEMAPHORES          5
#define CONTEXT_BANNED                  6
#define CONTEXT_FORCE_SINGLE_SUBMISSION 7
#define CONTEXT_NOPREEMPT               8
#define CONTEXT_LRCA_DIRTY              9
#define CONTEXT_GUC_INIT                10
#define CONTEXT_PERMA_PIN               11
#define CONTEXT_IS_PARKING              12
#define CONTEXT_EXITING                 13
#define CONTEXT_LOW_LATENCY             14
#define CONTEXT_OWN_STATE               15

        struct {
                u64 timeout_us;
        } watchdog;

        u32 *lrc_reg_state;
        union {
                struct {
                        u32 lrca;
                        u32 ccid;
                };
                u64 desc;
        } lrc;
        u32 tag; /* cookie passed to HW to track this context on submission */

        /** stats: Context GPU engine busyness tracking. */
        struct intel_context_stats {
                u64 active;

                /* Time on GPU as tracked by the hw. */
                struct {
                        struct ewma_runtime avg;
                        u64 total;
                        u32 last;
                        I915_SELFTEST_DECLARE(u32 num_underflow);
                        I915_SELFTEST_DECLARE(u32 max_underflow);
                } runtime;
        } stats;

        unsigned int active_count; /* protected by timeline->mutex */

        atomic_t pin_count;
        struct mutex pin_mutex; /* guards pinning and associated on-gpuing */

        /**
         * active: Active tracker for the rq activity (inc. external) on this
         * intel_context object.
         */
        struct i915_active active;

        const struct intel_context_ops *ops;

        /** sseu: Control eu/slice partitioning */
        struct intel_sseu sseu;

        /**
         * pinned_contexts_link: List link for the engine's pinned contexts.
         * This is only used if this is a perma-pinned kernel context and
         * the list is assumed to only be manipulated during driver load
         * or unload time so no mutex protection currently.
         */
        struct list_head pinned_contexts_link;

        u8 wa_bb_page; /* if set, page num reserved for context workarounds */

        struct {
                /** @lock: protects everything in guc_state */
                spinlock_t lock;
                /**
                 * @sched_state: scheduling state of this context using GuC
                 * submission
                 */
                u32 sched_state;
                /*
                 * @fences: maintains a list of requests that are currently
                 * being fenced until a GuC operation completes
                 */
                struct list_head fences;
                /**
                 * @blocked: fence used to signal when the blocking of a
                 * context's submissions is complete.
                 */
                struct i915_sw_fence blocked;
                /** @requests: list of active requests on this context */
                struct list_head requests;
                /** @prio: the context's current guc priority */
                u8 prio;
                /**
                 * @prio_count: a counter of the number requests in flight in
                 * each priority bucket
                 */
                u32 prio_count[GUC_CLIENT_PRIORITY_NUM];
                /**
                 * @sched_disable_delay_work: worker to disable scheduling on this
                 * context
                 */
                struct delayed_work sched_disable_delay_work;
        } guc_state;

        struct {
                /**
                 * @id: handle which is used to uniquely identify this context
                 * with the GuC, protected by guc->submission_state.lock
                 */
                u16 id;
                /**
                 * @ref: the number of references to the guc_id, when
                 * transitioning in and out of zero protected by
                 * guc->submission_state.lock
                 */
                atomic_t ref;
                /**
                 * @link: in guc->guc_id_list when the guc_id has no refs but is
                 * still valid, protected by guc->submission_state.lock
                 */
                struct list_head link;
        } guc_id;

        /**
         * @destroyed_link: link in guc->submission_state.destroyed_contexts, in
         * list when context is pending to be destroyed (deregistered with the
         * GuC), protected by guc->submission_state.lock
         */
        struct list_head destroyed_link;

        /** @parallel: sub-structure for parallel submission members */
        struct {
                union {
                        /**
                         * @child_list: parent's list of children
                         * contexts, no protection as immutable after context
                         * creation
                         */
                        struct list_head child_list;
                        /**
                         * @child_link: child's link into parent's list of
                         * children
                         */
                        struct list_head child_link;
                };
                /** @parent: pointer to parent if child */
                struct intel_context *parent;
                /**
                 * @last_rq: last request submitted on a parallel context, used
                 * to insert submit fences between requests in the parallel
                 * context
                 */
                struct i915_request *last_rq;
                /**
                 * @fence_context: fence context composite fence when doing
                 * parallel submission
                 */
                u64 fence_context;
                /**
                 * @seqno: seqno for composite fence when doing parallel
                 * submission
                 */
                u32 seqno;
                /** @number_children: number of children if parent */
                u8 number_children;
                /** @child_index: index into child_list if child */
                u8 child_index;
                /** @guc: GuC specific members for parallel submission */
                struct {
                        /** @wqi_head: cached head pointer in work queue */
                        u16 wqi_head;
                        /** @wqi_tail: cached tail pointer in work queue */
                        u16 wqi_tail;
                        /** @wq_head: pointer to the actual head in work queue */
                        u32 *wq_head;
                        /** @wq_tail: pointer to the actual head in work queue */
                        u32 *wq_tail;
                        /** @wq_status: pointer to the status in work queue */
                        u32 *wq_status;

                        /**
                         * @parent_page: page in context state (ce->state) used
                         * by parent for work queue, process descriptor
                         */
                        u8 parent_page;
                } guc;
        } parallel;

#ifdef CONFIG_DRM_I915_SELFTEST
        /**
         * @drop_schedule_enable: Force drop of schedule enable G2H for selftest
         */
        bool drop_schedule_enable;

        /**
         * @drop_schedule_disable: Force drop of schedule disable G2H for
         * selftest
         */
        bool drop_schedule_disable;

        /**
         * @drop_deregister: Force drop of deregister G2H for selftest
         */
        bool drop_deregister;
#endif
};

#endif /* __INTEL_CONTEXT_TYPES__ */