/*
 * Copyright 2015 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.
 *
 *
 */
#include <linux/kthread.h>
#include <linux/wait.h>
#include <linux/sched.h>

#include <drm/drm_drv.h>

#include "amdgpu.h"
#include "amdgpu_trace.h"

static enum drm_gpu_sched_stat amdgpu_job_timedout(struct drm_sched_job *s_job)
{
        struct amdgpu_ring *ring = to_amdgpu_ring(s_job->sched);
        struct amdgpu_job *job = to_amdgpu_job(s_job);
        struct amdgpu_task_info ti;
        struct amdgpu_device *adev = ring->adev;
        int idx;

        if (!drm_dev_enter(&adev->ddev, &idx)) {
                DRM_INFO("%s - device unplugged skipping recovery on scheduler:%s",
                         __func__, s_job->sched->name);

                /* Effectively the job is aborted as the device is gone */
                return DRM_GPU_SCHED_STAT_ENODEV;
        }

        memset(&ti, 0, sizeof(struct amdgpu_task_info));

        if (amdgpu_gpu_recovery &&
            amdgpu_ring_soft_recovery(ring, job->vmid, s_job->s_fence->parent)) {
                DRM_ERROR("ring %s timeout, but soft recovered\n",
                          s_job->sched->name);
                goto exit;
        }

        amdgpu_vm_get_task_info(ring->adev, job->pasid, &ti);
        DRM_ERROR("ring %s timeout, signaled seq=%u, emitted seq=%u\n",
                  job->base.sched->name, atomic_read(&ring->fence_drv.last_seq),
                  ring->fence_drv.sync_seq);
        DRM_ERROR("Process information: process %s pid %d thread %s pid %d\n",
                  ti.process_name, ti.tgid, ti.task_name, ti.pid);

        if (amdgpu_device_should_recover_gpu(ring->adev)) {
                amdgpu_device_gpu_recover(ring->adev, job);
        } else {
                drm_sched_suspend_timeout(&ring->sched);
                if (amdgpu_sriov_vf(adev))
                        adev->virt.tdr_debug = true;
        }

exit:
        drm_dev_exit(idx);
        return DRM_GPU_SCHED_STAT_NOMINAL;
}

int amdgpu_job_alloc(struct amdgpu_device *adev, unsigned num_ibs,
                     struct amdgpu_job **job, struct amdgpu_vm *vm)
{
        size_t size = sizeof(struct amdgpu_job);

        if (num_ibs == 0)
                return -EINVAL;

        size += sizeof(struct amdgpu_ib) * num_ibs;

        *job = kzalloc(size, GFP_KERNEL);
        if (!*job)
                return -ENOMEM;

        /*
         * Initialize the scheduler to at least some ring so that we always
         * have a pointer to adev.
         */
        (*job)->base.sched = &adev->rings[0]->sched;
        (*job)->vm = vm;
        (*job)->ibs = (void *)&(*job)[1];
        (*job)->num_ibs = num_ibs;

        amdgpu_sync_create(&(*job)->sync);
        amdgpu_sync_create(&(*job)->sched_sync);
        (*job)->vram_lost_counter = atomic_read(&adev->vram_lost_counter);
        (*job)->vm_pd_addr = AMDGPU_BO_INVALID_OFFSET;

        return 0;
}

int amdgpu_job_alloc_with_ib(struct amdgpu_device *adev, unsigned size,
                enum amdgpu_ib_pool_type pool_type,
                struct amdgpu_job **job)
{
        int r;

        r = amdgpu_job_alloc(adev, 1, job, NULL);
        if (r)
                return r;

        r = amdgpu_ib_get(adev, NULL, size, pool_type, &(*job)->ibs[0]);
        if (r)
                kfree(*job);

        return r;
}

void amdgpu_job_free_resources(struct amdgpu_job *job)
{
        struct amdgpu_ring *ring = to_amdgpu_ring(job->base.sched);
        struct dma_fence *f;
        struct dma_fence *hw_fence;
        unsigned i;

        if (job->hw_fence.ops == NULL)
                hw_fence = job->external_hw_fence;
        else
                hw_fence = &job->hw_fence;

        /* use sched fence if available */
        f = job->base.s_fence ? &job->base.s_fence->finished : hw_fence;
        for (i = 0; i < job->num_ibs; ++i)
                amdgpu_ib_free(ring->adev, &job->ibs[i], f);
}

static void amdgpu_job_free_cb(struct drm_sched_job *s_job)
{
        struct amdgpu_job *job = to_amdgpu_job(s_job);

        drm_sched_job_cleanup(s_job);

        amdgpu_sync_free(&job->sync);
        amdgpu_sync_free(&job->sched_sync);

    /* only put the hw fence if has embedded fence */
        if (job->hw_fence.ops != NULL)
                dma_fence_put(&job->hw_fence);
        else
                kfree(job);
}

void amdgpu_job_free(struct amdgpu_job *job)
{
        amdgpu_job_free_resources(job);
        amdgpu_sync_free(&job->sync);
        amdgpu_sync_free(&job->sched_sync);

        /* only put the hw fence if has embedded fence */
        if (job->hw_fence.ops != NULL)
                dma_fence_put(&job->hw_fence);
        else
                kfree(job);
}

int amdgpu_job_submit(struct amdgpu_job *job, struct drm_sched_entity *entity,
                      void *owner, struct dma_fence **f)
{
        int r;

        if (!f)
                return -EINVAL;

        r = drm_sched_job_init(&job->base, entity, owner);
        if (r)
                return r;

        *f = dma_fence_get(&job->base.s_fence->finished);
        amdgpu_job_free_resources(job);
        drm_sched_entity_push_job(&job->base, entity);

        return 0;
}

int amdgpu_job_submit_direct(struct amdgpu_job *job, struct amdgpu_ring *ring,
                             struct dma_fence **fence)
{
        int r;

        job->base.sched = &ring->sched;
        r = amdgpu_ib_schedule(ring, job->num_ibs, job->ibs, NULL, fence);
        /* record external_hw_fence for direct submit */
        job->external_hw_fence = dma_fence_get(*fence);
        if (r)
                return r;

        amdgpu_job_free(job);
        dma_fence_put(*fence);

        return 0;
}

static struct dma_fence *amdgpu_job_dependency(struct drm_sched_job *sched_job,
                                               struct drm_sched_entity *s_entity)
{
        struct amdgpu_ring *ring = to_amdgpu_ring(s_entity->rq->sched);
        struct amdgpu_job *job = to_amdgpu_job(sched_job);
        struct amdgpu_vm *vm = job->vm;
        struct dma_fence *fence;
        int r;

        fence = amdgpu_sync_get_fence(&job->sync);
        if (fence && drm_sched_dependency_optimized(fence, s_entity)) {
                r = amdgpu_sync_fence(&job->sched_sync, fence);
                if (r)
                        DRM_ERROR("Error adding fence (%d)\n", r);
        }

        while (fence == NULL && vm && !job->vmid) {
                r = amdgpu_vmid_grab(vm, ring, &job->sync,
                                     &job->base.s_fence->finished,
                                     job);
                if (r)
                        DRM_ERROR("Error getting VM ID (%d)\n", r);

                fence = amdgpu_sync_get_fence(&job->sync);
        }

        return fence;
}

static struct dma_fence *amdgpu_job_run(struct drm_sched_job *sched_job)
{
        struct amdgpu_ring *ring = to_amdgpu_ring(sched_job->sched);
        struct dma_fence *fence = NULL, *finished;
        struct amdgpu_job *job;
        int r = 0;

        job = to_amdgpu_job(sched_job);
        finished = &job->base.s_fence->finished;

        BUG_ON(amdgpu_sync_peek_fence(&job->sync, NULL));

        trace_amdgpu_sched_run_job(job);

        if (job->vram_lost_counter != atomic_read(&ring->adev->vram_lost_counter))
                dma_fence_set_error(finished, -ECANCELED);/* skip IB as well if VRAM lost */

        if (finished->error < 0) {
                DRM_INFO("Skip scheduling IBs!\n");
        } else {
                r = amdgpu_ib_schedule(ring, job->num_ibs, job->ibs, job,
                                       &fence);
                if (r)
                        DRM_ERROR("Error scheduling IBs (%d)\n", r);
        }

        if (!job->job_run_counter)
                dma_fence_get(fence);
        else if (finished->error < 0)
                dma_fence_put(&job->hw_fence);
        job->job_run_counter++;
        amdgpu_job_free_resources(job);

        fence = r ? ERR_PTR(r) : fence;
        return fence;
}

#define to_drm_sched_job(sched_job)             \
                container_of((sched_job), struct drm_sched_job, queue_node)

void amdgpu_job_stop_all_jobs_on_sched(struct drm_gpu_scheduler *sched)
{
        struct drm_sched_job *s_job;
        struct drm_sched_entity *s_entity = NULL;
        int i;

        /* Signal all jobs not yet scheduled */
        for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
                struct drm_sched_rq *rq = &sched->sched_rq[i];

                if (!rq)
                        continue;

                spin_lock(&rq->lock);
                list_for_each_entry(s_entity, &rq->entities, list) {
                        while ((s_job = to_drm_sched_job(spsc_queue_pop(&s_entity->job_queue)))) {
                                struct drm_sched_fence *s_fence = s_job->s_fence;

                                dma_fence_signal(&s_fence->scheduled);
                                dma_fence_set_error(&s_fence->finished, -EHWPOISON);
                                dma_fence_signal(&s_fence->finished);
                        }
                }
                spin_unlock(&rq->lock);
        }

        /* Signal all jobs already scheduled to HW */
        list_for_each_entry(s_job, &sched->pending_list, list) {
                struct drm_sched_fence *s_fence = s_job->s_fence;

                dma_fence_set_error(&s_fence->finished, -EHWPOISON);
                dma_fence_signal(&s_fence->finished);
        }
}

const struct drm_sched_backend_ops amdgpu_sched_ops = {
        .dependency = amdgpu_job_dependency,
        .run_job = amdgpu_job_run,
        .timedout_job = amdgpu_job_timedout,
        .free_job = amdgpu_job_free_cb
};