/*
 * 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;
}