/*
 * Copyright 2012 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.
 *
 * Authors: Ben Skeggs
 */
#include "chan.h"

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

struct nvkm_fifo_chan_object {
        struct nvkm_oproxy oproxy;
        struct nvkm_fifo_chan *chan;
        int hash;
};

static int
nvkm_fifo_chan_child_fini(struct nvkm_oproxy *base, bool suspend)
{
        struct nvkm_fifo_chan_object *object =
                container_of(base, typeof(*object), oproxy);
        struct nvkm_engine *engine  = object->oproxy.object->engine;
        struct nvkm_fifo_chan *chan = object->chan;
        struct nvkm_fifo_engn *engn = &chan->engn[engine->subdev.index];
        const char *name = nvkm_subdev_name[engine->subdev.index];
        int ret = 0;

        if (--engn->usecount)
                return 0;

        if (chan->func->engine_fini) {
                ret = chan->func->engine_fini(chan, engine, suspend);
                if (ret) {
                        nvif_error(&chan->object,
                                   "detach %s failed, %d\n", name, ret);
                        return ret;
                }
        }

        if (engn->object) {
                ret = nvkm_object_fini(engn->object, suspend);
                if (ret && suspend)
                        return ret;
        }

        nvif_trace(&chan->object, "detached %s\n", name);
        return ret;
}

static int
nvkm_fifo_chan_child_init(struct nvkm_oproxy *base)
{
        struct nvkm_fifo_chan_object *object =
                container_of(base, typeof(*object), oproxy);
        struct nvkm_engine *engine  = object->oproxy.object->engine;
        struct nvkm_fifo_chan *chan = object->chan;
        struct nvkm_fifo_engn *engn = &chan->engn[engine->subdev.index];
        const char *name = nvkm_subdev_name[engine->subdev.index];
        int ret;

        if (engn->usecount++)
                return 0;

        if (engn->object) {
                ret = nvkm_object_init(engn->object);
                if (ret)
                        return ret;
        }

        if (chan->func->engine_init) {
                ret = chan->func->engine_init(chan, engine);
                if (ret) {
                        nvif_error(&chan->object,
                                   "attach %s failed, %d\n", name, ret);
                        return ret;
                }
        }

        nvif_trace(&chan->object, "attached %s\n", name);
        return 0;
}

static void
nvkm_fifo_chan_child_del(struct nvkm_oproxy *base)
{
        struct nvkm_fifo_chan_object *object =
                container_of(base, typeof(*object), oproxy);
        struct nvkm_engine *engine  = object->oproxy.base.engine;
        struct nvkm_fifo_chan *chan = object->chan;
        struct nvkm_fifo_engn *engn = &chan->engn[engine->subdev.index];

        if (chan->func->object_dtor)
                chan->func->object_dtor(chan, object->hash);

        if (!--engn->refcount) {
                if (chan->func->engine_dtor)
                        chan->func->engine_dtor(chan, engine);
                nvkm_object_del(&engn->object);
                if (chan->vm)
                        atomic_dec(&chan->vm->engref[engine->subdev.index]);
        }
}

static const struct nvkm_oproxy_func
nvkm_fifo_chan_child_func = {
        .dtor[0] = nvkm_fifo_chan_child_del,
        .init[0] = nvkm_fifo_chan_child_init,
        .fini[0] = nvkm_fifo_chan_child_fini,
};

static int
nvkm_fifo_chan_child_new(const struct nvkm_oclass *oclass, void *data, u32 size,
                         struct nvkm_object **pobject)
{
        struct nvkm_engine *engine = oclass->engine;
        struct nvkm_fifo_chan *chan = nvkm_fifo_chan(oclass->parent);
        struct nvkm_fifo_engn *engn = &chan->engn[engine->subdev.index];
        struct nvkm_fifo_chan_object *object;
        int ret = 0;

        if (!(object = kzalloc(sizeof(*object), GFP_KERNEL)))
                return -ENOMEM;
        nvkm_oproxy_ctor(&nvkm_fifo_chan_child_func, oclass, &object->oproxy);
        object->chan = chan;
        *pobject = &object->oproxy.base;

        if (!engn->refcount++) {
                struct nvkm_oclass cclass = {
                        .client = oclass->client,
                        .engine = oclass->engine,
                };

                if (chan->vm)
                        atomic_inc(&chan->vm->engref[engine->subdev.index]);

                if (engine->func->fifo.cclass) {
                        ret = engine->func->fifo.cclass(chan, &cclass,
                                                        &engn->object);
                } else
                if (engine->func->cclass) {
                        ret = nvkm_object_new_(engine->func->cclass, &cclass,
                                               NULL, 0, &engn->object);
                }
                if (ret)
                        return ret;

                if (chan->func->engine_ctor) {
                        ret = chan->func->engine_ctor(chan, oclass->engine,
                                                      engn->object);
                        if (ret)
                                return ret;
                }
        }

        ret = oclass->base.ctor(&(const struct nvkm_oclass) {
                                        .base = oclass->base,
                                        .engn = oclass->engn,
                                        .handle = oclass->handle,
                                        .object = oclass->object,
                                        .client = oclass->client,
                                        .parent = engn->object ?
                                                  engn->object :
                                                  oclass->parent,
                                        .engine = engine,
                                }, data, size, &object->oproxy.object);
        if (ret)
                return ret;

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

        return 0;
}

static int
nvkm_fifo_chan_child_get(struct nvkm_object *object, int index,
                         struct nvkm_oclass *oclass)
{
        struct nvkm_fifo_chan *chan = nvkm_fifo_chan(object);
        struct nvkm_fifo *fifo = chan->fifo;
        struct nvkm_device *device = fifo->engine.subdev.device;
        struct nvkm_engine *engine;
        u64 mask = chan->engines;
        int ret, i, c;

        for (; c = 0, i = __ffs64(mask), mask; mask &= ~(1ULL << i)) {
                if (!(engine = nvkm_device_engine(device, i)))
                        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_fifo_chan_child_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_fifo_chan_child_new;
                                return 0;
                        }
                }
                index -= c;
        }

        return -EINVAL;
}

static int
nvkm_fifo_chan_ntfy(struct nvkm_object *object, u32 type,
                    struct nvkm_event **pevent)
{
        struct nvkm_fifo_chan *chan = nvkm_fifo_chan(object);
        if (chan->func->ntfy)
                return chan->func->ntfy(chan, type, pevent);
        return -ENODEV;
}

static int
nvkm_fifo_chan_map(struct nvkm_object *object, u64 *addr, u32 *size)
{
        struct nvkm_fifo_chan *chan = nvkm_fifo_chan(object);
        *addr = chan->addr;
        *size = chan->size;
        return 0;
}

static int
nvkm_fifo_chan_rd32(struct nvkm_object *object, u64 addr, u32 *data)
{
        struct nvkm_fifo_chan *chan = nvkm_fifo_chan(object);
        if (unlikely(!chan->user)) {
                chan->user = ioremap(chan->addr, chan->size);
                if (!chan->user)
                        return -ENOMEM;
        }
        if (unlikely(addr + 4 > chan->size))
                return -EINVAL;
        *data = ioread32_native(chan->user + addr);
        return 0;
}

static int
nvkm_fifo_chan_wr32(struct nvkm_object *object, u64 addr, u32 data)
{
        struct nvkm_fifo_chan *chan = nvkm_fifo_chan(object);
        if (unlikely(!chan->user)) {
                chan->user = ioremap(chan->addr, chan->size);
                if (!chan->user)
                        return -ENOMEM;
        }
        if (unlikely(addr + 4 > chan->size))
                return -EINVAL;
        iowrite32_native(data, chan->user + addr);
        return 0;
}

static int
nvkm_fifo_chan_fini(struct nvkm_object *object, bool suspend)
{
        struct nvkm_fifo_chan *chan = nvkm_fifo_chan(object);
        chan->func->fini(chan);
        return 0;
}

static int
nvkm_fifo_chan_init(struct nvkm_object *object)
{
        struct nvkm_fifo_chan *chan = nvkm_fifo_chan(object);
        chan->func->init(chan);
        return 0;
}

static void *
nvkm_fifo_chan_dtor(struct nvkm_object *object)
{
        struct nvkm_fifo_chan *chan = nvkm_fifo_chan(object);
        struct nvkm_fifo *fifo = chan->fifo;
        void *data = chan->func->dtor(chan);
        unsigned long flags;

        spin_lock_irqsave(&fifo->lock, flags);
        if (!list_empty(&chan->head)) {
                __clear_bit(chan->chid, fifo->mask);
                list_del(&chan->head);
        }
        spin_unlock_irqrestore(&fifo->lock, flags);

        if (chan->user)
                iounmap(chan->user);

        nvkm_vm_ref(NULL, &chan->vm, NULL);

        nvkm_gpuobj_del(&chan->push);
        nvkm_gpuobj_del(&chan->inst);
        return data;
}

static const struct nvkm_object_func
nvkm_fifo_chan_func = {
        .dtor = nvkm_fifo_chan_dtor,
        .init = nvkm_fifo_chan_init,
        .fini = nvkm_fifo_chan_fini,
        .ntfy = nvkm_fifo_chan_ntfy,
        .map = nvkm_fifo_chan_map,
        .rd32 = nvkm_fifo_chan_rd32,
        .wr32 = nvkm_fifo_chan_wr32,
        .sclass = nvkm_fifo_chan_child_get,
};

int
nvkm_fifo_chan_ctor(const struct nvkm_fifo_chan_func *func,
                    struct nvkm_fifo *fifo, u32 size, u32 align, bool zero,
                    u64 vm, u64 push, u64 engines, int bar, u32 base, u32 user,
                    const struct nvkm_oclass *oclass,
                    struct nvkm_fifo_chan *chan)
{
        struct nvkm_client *client = oclass->client;
        struct nvkm_device *device = fifo->engine.subdev.device;
        struct nvkm_mmu *mmu = device->mmu;
        struct nvkm_dmaobj *dmaobj;
        unsigned long flags;
        int ret;

        nvkm_object_ctor(&nvkm_fifo_chan_func, oclass, &chan->object);
        chan->func = func;
        chan->fifo = fifo;
        chan->engines = engines;
        INIT_LIST_HEAD(&chan->head);

        /* instance memory */
        ret = nvkm_gpuobj_new(device, size, align, zero, NULL, &chan->inst);
        if (ret)
                return ret;

        /* allocate push buffer ctxdma instance */
        if (push) {
                dmaobj = nvkm_dma_search(device->dma, oclass->client, push);
                if (!dmaobj)
                        return -ENOENT;

                ret = nvkm_object_bind(&dmaobj->object, chan->inst, -16,
                                       &chan->push);
                if (ret)
                        return ret;
        }

        /* channel address space */
        if (!vm && mmu) {
                if (!client->vm || client->vm->mmu == mmu) {
                        ret = nvkm_vm_ref(client->vm, &chan->vm, NULL);
                        if (ret)
                                return ret;
                } else {
                        return -EINVAL;
                }
        } else {
                return -ENOENT;
        }

        /* allocate channel id */
        spin_lock_irqsave(&fifo->lock, flags);
        chan->chid = find_first_zero_bit(fifo->mask, NVKM_FIFO_CHID_NR);
        if (chan->chid >= NVKM_FIFO_CHID_NR) {
                spin_unlock_irqrestore(&fifo->lock, flags);
                return -ENOSPC;
        }
        list_add(&chan->head, &fifo->chan);
        __set_bit(chan->chid, fifo->mask);
        spin_unlock_irqrestore(&fifo->lock, flags);

        /* determine address of this channel's user registers */
        chan->addr = device->func->resource_addr(device, bar) +
                     base + user * chan->chid;
        chan->size = user;

        nvkm_event_send(&fifo->cevent, 1, 0, NULL, 0);
        return 0;
}