/*
 * Copyright 2019 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 "amdgpu_vm.h"
#include "amdgpu_job.h"
#include "amdgpu_object.h"
#include "amdgpu_trace.h"

#define AMDGPU_VM_SDMA_MIN_NUM_DW       256u
#define AMDGPU_VM_SDMA_MAX_NUM_DW       (16u * 1024u)

/**
 * amdgpu_vm_sdma_map_table - make sure new PDs/PTs are GTT mapped
 *
 * @table: newly allocated or validated PD/PT
 */
static int amdgpu_vm_sdma_map_table(struct amdgpu_bo *table)
{
        int r;

        r = amdgpu_ttm_alloc_gart(&table->tbo);
        if (r)
                return r;

        if (table->shadow)
                r = amdgpu_ttm_alloc_gart(&table->shadow->tbo);

        return r;
}

/**
 * amdgpu_vm_sdma_prepare - prepare SDMA command submission
 *
 * @p: see amdgpu_vm_update_params definition
 * @owner: owner we need to sync to
 * @exclusive: exclusive move fence we need to sync to
 *
 * Returns:
 * Negativ errno, 0 for success.
 */
static int amdgpu_vm_sdma_prepare(struct amdgpu_vm_update_params *p,
                                  void *owner, struct dma_fence *exclusive)
{
        struct amdgpu_bo *root = p->vm->root.base.bo;
        unsigned int ndw = AMDGPU_VM_SDMA_MIN_NUM_DW;
        int r;

        r = amdgpu_job_alloc_with_ib(p->adev, ndw * 4, &p->job);
        if (r)
                return r;

        r = amdgpu_sync_fence(p->adev, &p->job->sync, exclusive, false);
        if (r)
                return r;

        r = amdgpu_sync_resv(p->adev, &p->job->sync, root->tbo.resv,
                             owner, false);
        if (r)
                return r;

        p->num_dw_left = ndw;
        return 0;
}

/**
 * amdgpu_vm_sdma_commit - commit SDMA command submission
 *
 * @p: see amdgpu_vm_update_params definition
 * @fence: resulting fence
 *
 * Returns:
 * Negativ errno, 0 for success.
 */
static int amdgpu_vm_sdma_commit(struct amdgpu_vm_update_params *p,
                                 struct dma_fence **fence)
{
        struct amdgpu_bo *root = p->vm->root.base.bo;
        struct amdgpu_ib *ib = p->job->ibs;
        struct amdgpu_ring *ring;
        struct dma_fence *f;
        int r;

        ring = container_of(p->vm->entity.rq->sched, struct amdgpu_ring, sched);

        WARN_ON(ib->length_dw == 0);
        amdgpu_ring_pad_ib(ring, ib);
        WARN_ON(ib->length_dw > p->num_dw_left);
        r = amdgpu_job_submit(p->job, &p->vm->entity,
                              AMDGPU_FENCE_OWNER_VM, &f);
        if (r)
                goto error;

        amdgpu_bo_fence(root, f, true);
        if (fence)
                swap(*fence, f);
        dma_fence_put(f);
        return 0;

error:
        amdgpu_job_free(p->job);
        return r;
}


/**
 * amdgpu_vm_sdma_copy_ptes - copy the PTEs from mapping
 *
 * @p: see amdgpu_vm_update_params definition
 * @bo: PD/PT to update
 * @pe: addr of the page entry
 * @count: number of page entries to copy
 *
 * Traces the parameters and calls the DMA function to copy the PTEs.
 */
static void amdgpu_vm_sdma_copy_ptes(struct amdgpu_vm_update_params *p,
                                     struct amdgpu_bo *bo, uint64_t pe,
                                     unsigned count)
{
        struct amdgpu_ib *ib = p->job->ibs;
        uint64_t src = ib->gpu_addr;

        src += p->num_dw_left * 4;

        pe += amdgpu_bo_gpu_offset(bo);
        trace_amdgpu_vm_copy_ptes(pe, src, count);

        amdgpu_vm_copy_pte(p->adev, ib, pe, src, count);
}

/**
 * amdgpu_vm_sdma_set_ptes - helper to call the right asic function
 *
 * @p: see amdgpu_vm_update_params definition
 * @bo: PD/PT to update
 * @pe: addr of the page entry
 * @addr: dst addr to write into pe
 * @count: number of page entries to update
 * @incr: increase next addr by incr bytes
 * @flags: hw access flags
 *
 * Traces the parameters and calls the right asic functions
 * to setup the page table using the DMA.
 */
static void amdgpu_vm_sdma_set_ptes(struct amdgpu_vm_update_params *p,
                                    struct amdgpu_bo *bo, uint64_t pe,
                                    uint64_t addr, unsigned count,
                                    uint32_t incr, uint64_t flags)
{
        struct amdgpu_ib *ib = p->job->ibs;

        pe += amdgpu_bo_gpu_offset(bo);
        trace_amdgpu_vm_set_ptes(pe, addr, count, incr, flags);
        if (count < 3) {
                amdgpu_vm_write_pte(p->adev, ib, pe, addr | flags,
                                    count, incr);
        } else {
                amdgpu_vm_set_pte_pde(p->adev, ib, pe, addr,
                                      count, incr, flags);
        }
}

/**
 * amdgpu_vm_sdma_update - execute VM update
 *
 * @p: see amdgpu_vm_update_params definition
 * @bo: PD/PT to update
 * @pe: addr of the page entry
 * @addr: dst addr to write into pe
 * @count: number of page entries to update
 * @incr: increase next addr by incr bytes
 * @flags: hw access flags
 *
 * Reserve space in the IB, setup mapping buffer on demand and write commands to
 * the IB.
 */
static int amdgpu_vm_sdma_update(struct amdgpu_vm_update_params *p,
                                 struct amdgpu_bo *bo, uint64_t pe,
                                 uint64_t addr, unsigned count, uint32_t incr,
                                 uint64_t flags)
{
        unsigned int i, ndw, nptes;
        uint64_t *pte;
        int r;

        do {
                ndw = p->num_dw_left;
                ndw -= p->job->ibs->length_dw;

                if (ndw < 32) {
                        r = amdgpu_vm_sdma_commit(p, NULL);
                        if (r)
                                return r;

                        /* estimate how many dw we need */
                        ndw = 32;
                        if (p->pages_addr)
                                ndw += count * 2;
                        ndw = max(ndw, AMDGPU_VM_SDMA_MIN_NUM_DW);
                        ndw = min(ndw, AMDGPU_VM_SDMA_MAX_NUM_DW);

                        r = amdgpu_job_alloc_with_ib(p->adev, ndw * 4, &p->job);
                        if (r)
                                return r;

                        p->num_dw_left = ndw;
                }

                if (!p->pages_addr) {
                        /* set page commands needed */
                        if (bo->shadow)
                                amdgpu_vm_sdma_set_ptes(p, bo->shadow, pe, addr,
                                                        count, incr, flags);
                        amdgpu_vm_sdma_set_ptes(p, bo, pe, addr, count,
                                                incr, flags);
                        return 0;
                }

                /* copy commands needed */
                ndw -= p->adev->vm_manager.vm_pte_funcs->copy_pte_num_dw *
                        (bo->shadow ? 2 : 1);

                /* for padding */
                ndw -= 7;

                nptes = min(count, ndw / 2);

                /* Put the PTEs at the end of the IB. */
                p->num_dw_left -= nptes * 2;
                pte = (uint64_t *)&(p->job->ibs->ptr[p->num_dw_left]);
                for (i = 0; i < nptes; ++i, addr += incr) {
                        pte[i] = amdgpu_vm_map_gart(p->pages_addr, addr);
                        pte[i] |= flags;
                }

                if (bo->shadow)
                        amdgpu_vm_sdma_copy_ptes(p, bo->shadow, pe, nptes);
                amdgpu_vm_sdma_copy_ptes(p, bo, pe, nptes);

                pe += nptes * 8;
                count -= nptes;
        } while (count);

        return 0;
}

const struct amdgpu_vm_update_funcs amdgpu_vm_sdma_funcs = {
        .map_table = amdgpu_vm_sdma_map_table,
        .prepare = amdgpu_vm_sdma_prepare,
        .update = amdgpu_vm_sdma_update,
        .commit = amdgpu_vm_sdma_commit
};