/*
 * Copyright 2021 Red Hat 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.
 */
#define nvkm_uchan(p) container_of((p), struct nvkm_uchan, object)
#include "priv.h"
#include "cgrp.h"
#include "chan.h"
#include "chid.h"
#include "runl.h"

#include <core/gpuobj.h>
#include <core/oproxy.h>
#include <subdev/mmu.h>
#include <engine/dma.h>

#include <nvif/if0020.h>

struct nvkm_uchan {
        struct nvkm_object object;
        struct nvkm_chan *chan;
};

static int
nvkm_uchan_uevent(struct nvkm_object *object, void *argv, u32 argc, struct nvkm_uevent *uevent)
{
        struct nvkm_chan *chan = nvkm_uchan(object)->chan;
        struct nvkm_runl *runl = chan->cgrp->runl;
        union nvif_chan_event_args *args = argv;

        if (!uevent)
                return 0;
        if (argc != sizeof(args->v0) || args->v0.version != 0)
                return -ENOSYS;

        switch (args->v0.type) {
        case NVIF_CHAN_EVENT_V0_NON_STALL_INTR:
                return nvkm_uevent_add(uevent, &runl->fifo->nonstall.event, runl->id,
                                       NVKM_FIFO_NONSTALL_EVENT, NULL);
        case NVIF_CHAN_EVENT_V0_KILLED:
                return nvkm_uevent_add(uevent, &runl->chid->event, chan->id,
                                       NVKM_CHAN_EVENT_ERRORED, NULL);
        default:
                break;
        }

        return -ENOSYS;
}

struct nvkm_uobj {
        struct nvkm_oproxy oproxy;
        struct nvkm_chan *chan;
        struct nvkm_cctx *cctx;
        int hash;
};

static int
nvkm_uchan_object_fini_1(struct nvkm_oproxy *oproxy, enum nvkm_suspend_state suspend)
{
        struct nvkm_uobj *uobj = container_of(oproxy, typeof(*uobj), oproxy);
        struct nvkm_chan *chan = uobj->chan;
        struct nvkm_cctx *cctx = uobj->cctx;
        struct nvkm_ectx *ectx = cctx->vctx->ectx;

        if (!ectx->object)
                return 0;

        /* Unbind engine context from channel, if no longer required. */
        if (refcount_dec_and_mutex_lock(&cctx->uses, &chan->cgrp->mutex)) {
                nvkm_chan_cctx_bind(chan, ectx->engn, NULL);

                if (refcount_dec_and_test(&ectx->uses))
                        nvkm_object_fini(ectx->object, NVKM_POWEROFF);
                mutex_unlock(&chan->cgrp->mutex);
        }

        return 0;
}

static int
nvkm_uchan_object_init_0(struct nvkm_oproxy *oproxy)
{
        struct nvkm_uobj *uobj = container_of(oproxy, typeof(*uobj), oproxy);
        struct nvkm_chan *chan = uobj->chan;
        struct nvkm_cctx *cctx = uobj->cctx;
        struct nvkm_ectx *ectx = cctx->vctx->ectx;
        int ret = 0;

        if (!ectx->object)
                return 0;

        /* Bind engine context to channel, if it hasn't been already. */
        if (!refcount_inc_not_zero(&cctx->uses)) {
                mutex_lock(&chan->cgrp->mutex);
                if (!refcount_inc_not_zero(&cctx->uses)) {
                        if (!refcount_inc_not_zero(&ectx->uses)) {
                                ret = nvkm_object_init(ectx->object);
                                if (ret == 0)
                                        refcount_set(&ectx->uses, 1);
                        }

                        if (ret == 0) {
                                nvkm_chan_cctx_bind(chan, ectx->engn, cctx);
                                refcount_set(&cctx->uses, 1);
                        }
                }
                mutex_unlock(&chan->cgrp->mutex);
        }

        return ret;
}

static void
nvkm_uchan_object_dtor(struct nvkm_oproxy *oproxy)
{
        struct nvkm_uobj *uobj = container_of(oproxy, typeof(*uobj), oproxy);
        struct nvkm_engn *engn;

        if (!uobj->cctx)
                return;

        engn = uobj->cctx->vctx->ectx->engn;
        if (engn->func->ramht_del)
                engn->func->ramht_del(uobj->chan, uobj->hash);

        nvkm_chan_cctx_put(uobj->chan, &uobj->cctx);
}

static const struct nvkm_oproxy_func
nvkm_uchan_object = {
        .dtor[1] = nvkm_uchan_object_dtor,
        .init[0] = nvkm_uchan_object_init_0,
        .fini[1] = nvkm_uchan_object_fini_1,
};

static int
nvkm_uchan_object_new(const struct nvkm_oclass *oclass, void *argv, u32 argc,
                      struct nvkm_object **pobject)
{
        struct nvkm_chan *chan = nvkm_uchan(oclass->parent)->chan;
        struct nvkm_cgrp *cgrp = chan->cgrp;
        struct nvkm_engn *engn;
        struct nvkm_uobj *uobj;
        int ret;

        /* Lookup host engine state for target engine. */
        engn = nvkm_runl_find_engn(engn, cgrp->runl, engn->engine == oclass->engine);
        if (WARN_ON(!engn))
                return -EINVAL;

        /* Allocate SW object. */
        if (!(uobj = kzalloc_obj(*uobj)))
                return -ENOMEM;

        nvkm_oproxy_ctor(&nvkm_uchan_object, oclass, &uobj->oproxy);
        uobj->chan = chan;
        *pobject = &uobj->oproxy.base;

        /* Ref. channel context for target engine.*/
        ret = nvkm_chan_cctx_get(chan, engn, &uobj->cctx, oclass->client);
        if (ret)
                return ret;

        /* Allocate HW object. */
        ret = oclass->base.ctor(&(const struct nvkm_oclass) {
                                        .base = oclass->base,
                                        .engn = oclass->engn,
                                        .handle = oclass->handle,
                                        .object = oclass->object,
                                        .client = oclass->client,
                                        .parent = uobj->cctx->vctx->ectx->object ?: oclass->parent,
                                        .engine = engn->engine,
                                 }, argv, argc, &uobj->oproxy.object);
        if (ret)
                return ret;

        if (engn->func->ramht_add) {
                uobj->hash = engn->func->ramht_add(engn, uobj->oproxy.object, uobj->chan);
                if (uobj->hash < 0)
                        return uobj->hash;
        }

        return 0;
}

static int
nvkm_uchan_sclass(struct nvkm_object *object, int index, struct nvkm_oclass *oclass)
{
        struct nvkm_chan *chan = nvkm_uchan(object)->chan;
        struct nvkm_engn *engn;
        int ret, runq = 0;

        nvkm_runl_foreach_engn(engn, chan->cgrp->runl) {
                struct nvkm_engine *engine = engn->engine;
                int c = 0;

                /* Each runqueue, on runlists with multiple, has its own LCE. */
                if (engn->runl->func->runqs) {
                        if (engine->subdev.type == NVKM_ENGINE_CE) {
                                if (chan->runq != runq++)
                                        continue;
                        }
                }

                oclass->engine = engine;
                oclass->base.oclass = 0;

                if (engine->func->fifo.sclass) {
                        ret = engine->func->fifo.sclass(oclass, index);
                        if (oclass->base.oclass) {
                                if (!oclass->base.ctor)
                                        oclass->base.ctor = nvkm_object_new;
                                oclass->ctor = nvkm_uchan_object_new;
                                return 0;
                        }

                        index -= ret;
                        continue;
                }

                while (engine->func->sclass[c].oclass) {
                        if (c++ == index) {
                                oclass->base = engine->func->sclass[index];
                                if (!oclass->base.ctor)
                                        oclass->base.ctor = nvkm_object_new;
                                oclass->ctor = nvkm_uchan_object_new;
                                return 0;
                        }
                }

                index -= c;
        }

        return -EINVAL;
}

static int
nvkm_uchan_map(struct nvkm_object *object, void *argv, u32 argc,
               enum nvkm_object_map *type, u64 *addr, u64 *size)
{
        struct nvkm_chan *chan = nvkm_uchan(object)->chan;
        struct nvkm_device *device = chan->cgrp->runl->fifo->engine.subdev.device;

        if (!chan->func->userd->bar)
                return -ENOSYS;

        *type = NVKM_OBJECT_MAP_IO;
        *addr = device->func->resource_addr(device, chan->func->userd->bar) +
                chan->func->userd->base + chan->userd.base;
        *size = chan->func->userd->size;
        return 0;
}

static int
nvkm_uchan_fini(struct nvkm_object *object, enum nvkm_suspend_state suspend)
{
        struct nvkm_chan *chan = nvkm_uchan(object)->chan;

        nvkm_chan_block(chan);
        nvkm_chan_remove(chan, true);

        if (chan->func->unbind)
                chan->func->unbind(chan);

        return 0;
}

static int
nvkm_uchan_init(struct nvkm_object *object)
{
        struct nvkm_chan *chan = nvkm_uchan(object)->chan;

        if (atomic_read(&chan->errored))
                return 0;

        if (chan->func->bind)
                chan->func->bind(chan);

        nvkm_chan_allow(chan);
        nvkm_chan_insert(chan);
        return 0;
}

static void *
nvkm_uchan_dtor(struct nvkm_object *object)
{
        struct nvkm_uchan *uchan = nvkm_uchan(object);

        nvkm_chan_del(&uchan->chan);
        return uchan;
}

static const struct nvkm_object_func
nvkm_uchan = {
        .dtor = nvkm_uchan_dtor,
        .init = nvkm_uchan_init,
        .fini = nvkm_uchan_fini,
        .map = nvkm_uchan_map,
        .sclass = nvkm_uchan_sclass,
        .uevent = nvkm_uchan_uevent,
};

struct nvkm_chan *
nvkm_uchan_chan(struct nvkm_object *object)
{
        if (WARN_ON(object->func != &nvkm_uchan))
                return NULL;

        return nvkm_uchan(object)->chan;
}

int
nvkm_uchan_new(struct nvkm_fifo *fifo, struct nvkm_cgrp *cgrp, const struct nvkm_oclass *oclass,
               void *argv, u32 argc, struct nvkm_object **pobject)
{
        union nvif_chan_args *args = argv;
        struct nvkm_runl *runl;
        struct nvkm_vmm *vmm = NULL;
        struct nvkm_dmaobj *ctxdma = NULL;
        struct nvkm_memory *userd = NULL;
        struct nvkm_uchan *uchan;
        struct nvkm_chan *chan;
        int ret;

        if (argc < sizeof(args->v0) || args->v0.version != 0)
                return -ENOSYS;
        argc -= sizeof(args->v0);

        if (args->v0.namelen != argc)
                return -EINVAL;

        /* Lookup objects referenced in args. */
        runl = nvkm_runl_get(fifo, args->v0.runlist, 0);
        if (!runl)
                return -EINVAL;

        if (args->v0.vmm) {
                vmm = nvkm_uvmm_search(oclass->client, args->v0.vmm);
                if (IS_ERR(vmm))
                        return PTR_ERR(vmm);
        }

        if (args->v0.ctxdma) {
                ctxdma = nvkm_dmaobj_search(oclass->client, args->v0.ctxdma);
                if (IS_ERR(ctxdma)) {
                        ret = PTR_ERR(ctxdma);
                        goto done;
                }
        }

        if (args->v0.huserd) {
                userd = nvkm_umem_search(oclass->client, args->v0.huserd);
                if (IS_ERR(userd)) {
                        ret = PTR_ERR(userd);
                        userd = NULL;
                        goto done;
                }
        }

        /* Allocate channel. */
        if (!(uchan = kzalloc_obj(*uchan))) {
                ret = -ENOMEM;
                goto done;
        }

        nvkm_object_ctor(&nvkm_uchan, oclass, &uchan->object);
        *pobject = &uchan->object;

        ret = nvkm_chan_new_(fifo->func->chan.func, runl, args->v0.runq, cgrp, args->v0.name,
                             args->v0.priv != 0, args->v0.devm, vmm, ctxdma, args->v0.offset,
                             args->v0.length, userd, args->v0.ouserd, &uchan->chan);
        if (ret)
                goto done;

        chan = uchan->chan;

        /* Return channel info to caller. */
        if (chan->func->doorbell_handle)
                args->v0.token = chan->func->doorbell_handle(chan);
        else
                args->v0.token = ~0;

        args->v0.chid = chan->id;

        switch (nvkm_memory_target(chan->inst->memory)) {
        case NVKM_MEM_TARGET_INST: args->v0.aper = NVIF_CHAN_V0_INST_APER_INST; break;
        case NVKM_MEM_TARGET_VRAM: args->v0.aper = NVIF_CHAN_V0_INST_APER_VRAM; break;
        case NVKM_MEM_TARGET_HOST: args->v0.aper = NVIF_CHAN_V0_INST_APER_HOST; break;
        case NVKM_MEM_TARGET_NCOH: args->v0.aper = NVIF_CHAN_V0_INST_APER_NCOH; break;
        default:
                WARN_ON(1);
                ret = -EFAULT;
                break;
        }

        args->v0.inst = nvkm_memory_addr(chan->inst->memory);
done:
        nvkm_memory_unref(&userd);
        nvkm_vmm_unref(&vmm);
        return ret;
}