/*
 * 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.
 */
#include <core/ramht.h>
#include <core/engine.h>
#include <core/object.h>

static u32
nvkm_ramht_hash(struct nvkm_ramht *ramht, int chid, u32 handle)
{
        u32 hash = 0;

        while (handle) {
                hash ^= (handle & ((1 << ramht->bits) - 1));
                handle >>= ramht->bits;
        }

        hash ^= chid << (ramht->bits - 4);
        return hash;
}

struct nvkm_gpuobj *
nvkm_ramht_search(struct nvkm_ramht *ramht, int chid, u32 handle)
{
        u32 co, ho;

        co = ho = nvkm_ramht_hash(ramht, chid, handle);
        do {
                if (ramht->data[co].chid == chid) {
                        if (ramht->data[co].handle == handle)
                                return ramht->data[co].inst;
                }

                if (++co >= ramht->size)
                        co = 0;
        } while (co != ho);

        return NULL;
}

static int
nvkm_ramht_update(struct nvkm_ramht *ramht, int co, struct nvkm_object *object,
                  int chid, int addr, u32 handle, u32 context)
{
        struct nvkm_ramht_data *data = &ramht->data[co];
        u64 inst = 0x00000040; /* just non-zero for <=g8x fifo ramht */
        int ret;

        nvkm_gpuobj_del(&data->inst);
        data->chid = chid;
        data->handle = handle;

        if (object) {
                ret = nvkm_object_bind(object, ramht->parent, 16, &data->inst);
                if (ret) {
                        if (ret != -ENODEV) {
                                data->chid = -1;
                                return ret;
                        }
                        data->inst = NULL;
                }

                if (data->inst) {
                        if (ramht->device->card_type >= NV_50)
                                inst = data->inst->node->offset;
                        else
                                inst = data->inst->addr;
                }

                if (addr < 0) context |= inst << -addr;
                else          context |= inst >>  addr;
        }

        nvkm_kmap(ramht->gpuobj);
        nvkm_wo32(ramht->gpuobj, (co << 3) + 0, handle);
        nvkm_wo32(ramht->gpuobj, (co << 3) + 4, context);
        nvkm_done(ramht->gpuobj);
        return co + 1;
}

void
nvkm_ramht_remove(struct nvkm_ramht *ramht, int cookie)
{
        if (--cookie >= 0)
                nvkm_ramht_update(ramht, cookie, NULL, -1, 0, 0, 0);
}

int
nvkm_ramht_insert(struct nvkm_ramht *ramht, struct nvkm_object *object,
                  int chid, int addr, u32 handle, u32 context)
{
        u32 co, ho;

        if (nvkm_ramht_search(ramht, chid, handle))
                return -EEXIST;

        co = ho = nvkm_ramht_hash(ramht, chid, handle);
        do {
                if (ramht->data[co].chid < 0) {
                        return nvkm_ramht_update(ramht, co, object, chid,
                                                 addr, handle, context);
                }

                if (++co >= ramht->size)
                        co = 0;
        } while (co != ho);

        return -ENOSPC;
}

void
nvkm_ramht_del(struct nvkm_ramht **pramht)
{
        struct nvkm_ramht *ramht = *pramht;
        if (ramht) {
                nvkm_gpuobj_del(&ramht->gpuobj);
                vfree(*pramht);
                *pramht = NULL;
        }
}

int
nvkm_ramht_new(struct nvkm_device *device, u32 size, u32 align,
               struct nvkm_gpuobj *parent, struct nvkm_ramht **pramht)
{
        struct nvkm_ramht *ramht;
        int ret, i;

        if (!(ramht = *pramht = vzalloc(struct_size(ramht, data, (size >> 3)))))
                return -ENOMEM;

        ramht->device = device;
        ramht->parent = parent;
        ramht->size = size >> 3;
        ramht->bits = order_base_2(ramht->size);
        for (i = 0; i < ramht->size; i++)
                ramht->data[i].chid = -1;

        ret = nvkm_gpuobj_new(ramht->device, size, align, true,
                              ramht->parent, &ramht->gpuobj);
        if (ret)
                nvkm_ramht_del(pramht);
        return ret;
}