// SPDX-License-Identifier: MIT
/*
 * Copyright © 2021 Intel Corporation
 */

#include "xe_sched_job.h"

#include <uapi/drm/xe_drm.h>
#include <linux/dma-fence-chain.h>
#include <linux/slab.h>

#include "xe_device.h"
#include "xe_exec_queue.h"
#include "xe_gt_types.h"
#include "xe_hw_engine_types.h"
#include "xe_hw_fence.h"
#include "xe_lrc.h"
#include "xe_macros.h"
#include "xe_pm.h"
#include "xe_sync_types.h"
#include "xe_trace.h"
#include "xe_vm.h"

static struct kmem_cache *xe_sched_job_slab;
static struct kmem_cache *xe_sched_job_parallel_slab;

int __init xe_sched_job_module_init(void)
{
        xe_sched_job_slab =
                kmem_cache_create("xe_sched_job",
                                  sizeof(struct xe_sched_job) +
                                  sizeof(struct xe_job_ptrs), 0,
                                  SLAB_HWCACHE_ALIGN, NULL);
        if (!xe_sched_job_slab)
                return -ENOMEM;

        xe_sched_job_parallel_slab =
                kmem_cache_create("xe_sched_job_parallel",
                                  sizeof(struct xe_sched_job) +
                                  sizeof(struct xe_job_ptrs) *
                                  XE_HW_ENGINE_MAX_INSTANCE, 0,
                                  SLAB_HWCACHE_ALIGN, NULL);
        if (!xe_sched_job_parallel_slab) {
                kmem_cache_destroy(xe_sched_job_slab);
                return -ENOMEM;
        }

        return 0;
}

void xe_sched_job_module_exit(void)
{
        kmem_cache_destroy(xe_sched_job_slab);
        kmem_cache_destroy(xe_sched_job_parallel_slab);
}

static struct xe_sched_job *job_alloc(bool parallel)
{
        return kmem_cache_zalloc(parallel ? xe_sched_job_parallel_slab :
                                 xe_sched_job_slab, GFP_KERNEL);
}

bool xe_sched_job_is_migration(struct xe_exec_queue *q)
{
        return q->vm && (q->vm->flags & XE_VM_FLAG_MIGRATION);
}

static void job_free(struct xe_sched_job *job)
{
        struct xe_exec_queue *q = job->q;
        bool is_migration = xe_sched_job_is_migration(q);

        kmem_cache_free(xe_exec_queue_is_parallel(job->q) || is_migration ?
                        xe_sched_job_parallel_slab : xe_sched_job_slab, job);
}

static struct xe_device *job_to_xe(struct xe_sched_job *job)
{
        return gt_to_xe(job->q->gt);
}

/* Free unused pre-allocated fences */
static void xe_sched_job_free_fences(struct xe_sched_job *job)
{
        int i;

        for (i = 0; i < job->q->width; ++i) {
                struct xe_job_ptrs *ptrs = &job->ptrs[i];

                if (ptrs->lrc_fence)
                        xe_lrc_free_seqno_fence(ptrs->lrc_fence);
                dma_fence_chain_free(ptrs->chain_fence);
        }
}

struct xe_sched_job *xe_sched_job_create(struct xe_exec_queue *q,
                                         u64 *batch_addr)
{
        bool is_migration = xe_sched_job_is_migration(q);
        struct xe_sched_job *job;
        int err;
        int i;
        u32 width;

        /* only a kernel context can submit a vm-less job */
        XE_WARN_ON(!q->vm && !(q->flags & EXEC_QUEUE_FLAG_KERNEL));

        job = job_alloc(xe_exec_queue_is_parallel(q) || is_migration);
        if (!job)
                return ERR_PTR(-ENOMEM);

        job->q = q;
        job->sample_timestamp = U64_MAX;
        kref_init(&job->refcount);
        xe_exec_queue_get(job->q);

        err = drm_sched_job_init(&job->drm, q->entity, 1, NULL,
                                 q->xef ? q->xef->drm->client_id : 0);
        if (err)
                goto err_free;

        for (i = 0; i < q->width; ++i) {
                struct dma_fence *fence = xe_lrc_alloc_seqno_fence();
                struct dma_fence_chain *chain;

                if (IS_ERR(fence)) {
                        err = PTR_ERR(fence);
                        goto err_sched_job;
                }
                job->ptrs[i].lrc_fence = fence;

                if (i + 1 == q->width)
                        continue;

                chain = dma_fence_chain_alloc();
                if (!chain) {
                        err = -ENOMEM;
                        goto err_sched_job;
                }
                job->ptrs[i].chain_fence = chain;
        }

        width = q->width;
        if (is_migration)
                width = 2;

        for (i = 0; i < width; ++i)
                job->ptrs[i].batch_addr = batch_addr[i];

        atomic_inc(&q->job_cnt);
        xe_pm_runtime_get_noresume(job_to_xe(job));
        trace_xe_sched_job_create(job);
        return job;

err_sched_job:
        xe_sched_job_free_fences(job);
        drm_sched_job_cleanup(&job->drm);
err_free:
        xe_exec_queue_put(q);
        job_free(job);
        return ERR_PTR(err);
}

/**
 * xe_sched_job_destroy - Destroy Xe schedule job
 * @ref: reference to Xe schedule job
 *
 * Called when ref == 0, drop a reference to job's xe_engine + fence, cleanup
 * base DRM schedule job, and free memory for Xe schedule job.
 */
void xe_sched_job_destroy(struct kref *ref)
{
        struct xe_sched_job *job =
                container_of(ref, struct xe_sched_job, refcount);
        struct xe_device *xe = job_to_xe(job);
        struct xe_exec_queue *q = job->q;

        xe_sched_job_free_fences(job);
        dma_fence_put(job->fence);
        drm_sched_job_cleanup(&job->drm);
        job_free(job);
        atomic_dec(&q->job_cnt);
        xe_exec_queue_put(q);
        xe_pm_runtime_put(xe);
}

/* Set the error status under the fence to avoid racing with signaling */
static bool xe_fence_set_error(struct dma_fence *fence, int error)
{
        unsigned long irq_flags;
        bool signaled;

        spin_lock_irqsave(fence->lock, irq_flags);
        signaled = test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags);
        if (!signaled)
                dma_fence_set_error(fence, error);
        spin_unlock_irqrestore(fence->lock, irq_flags);

        return signaled;
}

void xe_sched_job_set_error(struct xe_sched_job *job, int error)
{
        if (xe_fence_set_error(job->fence, error))
                return;

        if (dma_fence_is_chain(job->fence)) {
                struct dma_fence *iter;

                dma_fence_chain_for_each(iter, job->fence)
                        xe_fence_set_error(dma_fence_chain_contained(iter),
                                           error);
        }

        trace_xe_sched_job_set_error(job);

        dma_fence_enable_sw_signaling(job->fence);
        xe_hw_fence_irq_run(job->q->fence_irq);
}

bool xe_sched_job_started(struct xe_sched_job *job)
{
        struct dma_fence *fence = dma_fence_chain_contained(job->fence);
        struct xe_lrc *lrc = job->q->lrc[0];

        return !__dma_fence_is_later(fence,
                                     xe_sched_job_lrc_seqno(job),
                                     xe_lrc_start_seqno(lrc));
}

bool xe_sched_job_completed(struct xe_sched_job *job)
{
        struct dma_fence *fence = dma_fence_chain_contained(job->fence);
        struct xe_lrc *lrc = job->q->lrc[0];

        /*
         * Can safely check just LRC[0] seqno as that is last seqno written when
         * parallel handshake is done.
         */

        return !__dma_fence_is_later(fence,
                                     xe_sched_job_lrc_seqno(job),
                                     xe_lrc_seqno(lrc));
}

void xe_sched_job_arm(struct xe_sched_job *job)
{
        struct xe_exec_queue *q = job->q;
        struct dma_fence *fence, *prev;
        struct xe_vm *vm = q->vm;
        u64 seqno = 0;
        int i;

        /* Migration and kernel engines have their own locking */
        if (IS_ENABLED(CONFIG_LOCKDEP) &&
            !(q->flags & (EXEC_QUEUE_FLAG_KERNEL | EXEC_QUEUE_FLAG_VM))) {
                lockdep_assert_held(&q->vm->lock);
                if (!xe_vm_in_lr_mode(q->vm))
                        xe_vm_assert_held(q->vm);
        }

        if (vm && !xe_sched_job_is_migration(q) && !xe_vm_in_lr_mode(vm) &&
            (vm->batch_invalidate_tlb || vm->tlb_flush_seqno != q->tlb_flush_seqno)) {
                xe_vm_assert_held(vm);
                q->tlb_flush_seqno = vm->tlb_flush_seqno;
                job->ring_ops_flush_tlb = true;
        }

        /* Arm the pre-allocated fences */
        for (i = 0; i < q->width; prev = fence, ++i) {
                struct dma_fence_chain *chain;

                fence = job->ptrs[i].lrc_fence;
                xe_lrc_init_seqno_fence(q->lrc[i], fence);
                job->ptrs[i].lrc_fence = NULL;
                if (!i) {
                        job->lrc_seqno = fence->seqno;
                        continue;
                } else {
                        xe_assert(gt_to_xe(q->gt), job->lrc_seqno == fence->seqno);
                }

                chain = job->ptrs[i - 1].chain_fence;
                dma_fence_chain_init(chain, prev, fence, seqno++);
                job->ptrs[i - 1].chain_fence = NULL;
                fence = &chain->base;
        }

        job->fence = dma_fence_get(fence);      /* Pairs with put in scheduler */
        drm_sched_job_arm(&job->drm);
}

void xe_sched_job_push(struct xe_sched_job *job)
{
        xe_sched_job_get(job);
        trace_xe_sched_job_exec(job);
        drm_sched_entity_push_job(&job->drm);
        xe_sched_job_put(job);
}

/**
 * xe_sched_job_init_user_fence - Initialize user_fence for the job
 * @job: job whose user_fence needs an init
 * @sync: sync to be use to init user_fence
 */
void xe_sched_job_init_user_fence(struct xe_sched_job *job,
                                  struct xe_sync_entry *sync)
{
        if (sync->type != DRM_XE_SYNC_TYPE_USER_FENCE)
                return;

        job->user_fence.used = true;
        job->user_fence.addr = sync->addr;
        job->user_fence.value = sync->timeline_value;
}

struct xe_sched_job_snapshot *
xe_sched_job_snapshot_capture(struct xe_sched_job *job)
{
        struct xe_exec_queue *q = job->q;
        struct xe_device *xe = q->gt->tile->xe;
        struct xe_sched_job_snapshot *snapshot;
        size_t len = sizeof(*snapshot) + (sizeof(u64) * q->width);
        u16 i;

        snapshot = kzalloc(len, GFP_ATOMIC);
        if (!snapshot)
                return NULL;

        snapshot->batch_addr_len = q->width;
        for (i = 0; i < q->width; i++)
                snapshot->batch_addr[i] =
                        xe_device_uncanonicalize_addr(xe, job->ptrs[i].batch_addr);

        return snapshot;
}

void xe_sched_job_snapshot_free(struct xe_sched_job_snapshot *snapshot)
{
        kfree(snapshot);
}

void
xe_sched_job_snapshot_print(struct xe_sched_job_snapshot *snapshot,
                            struct drm_printer *p)
{
        u16 i;

        if (!snapshot)
                return;

        for (i = 0; i < snapshot->batch_addr_len; i++)
                drm_printf(p, "batch_addr[%u]: 0x%016llx\n", i, snapshot->batch_addr[i]);
}

int xe_sched_job_add_deps(struct xe_sched_job *job, struct dma_resv *resv,
                          enum dma_resv_usage usage)
{
        return drm_sched_job_add_resv_dependencies(&job->drm, resv, usage);
}