/*
 * Copyright 2016 Karol Herbst
 *
 * 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: Karol Herbst
 */
#include <subdev/bios.h>
#include <subdev/bios/bit.h>
#include <subdev/bios/vpstate.h>

static u32
nvbios_vpstate_offset(struct nvkm_bios *b)
{
        struct bit_entry bit_P;

        if (!bit_entry(b, 'P', &bit_P)) {
                if (bit_P.version == 2 && bit_P.length >= 0x3c)
                        return nvbios_rd32(b, bit_P.offset + 0x38);
        }

        return 0x0000;
}

int
nvbios_vpstate_parse(struct nvkm_bios *b, struct nvbios_vpstate_header *h)
{
        if (!h)
                return -EINVAL;

        h->offset = nvbios_vpstate_offset(b);
        if (!h->offset)
                return -ENODEV;

        h->version = nvbios_rd08(b, h->offset);
        switch (h->version) {
        case 0x10:
                h->hlen     = nvbios_rd08(b, h->offset + 0x1);
                h->elen     = nvbios_rd08(b, h->offset + 0x2);
                h->slen     = nvbios_rd08(b, h->offset + 0x3);
                h->scount   = nvbios_rd08(b, h->offset + 0x4);
                h->ecount   = nvbios_rd08(b, h->offset + 0x5);

                h->base_id  = nvbios_rd08(b, h->offset + 0x0f);
                if (h->hlen > 0x10)
                        h->boost_id = nvbios_rd08(b, h->offset + 0x10);
                else
                        h->boost_id = 0xff;
                if (h->hlen > 0x11)
                        h->tdp_id = nvbios_rd08(b, h->offset + 0x11);
                else
                        h->tdp_id = 0xff;
                return 0;
        default:
                return -EINVAL;
        }
}

int
nvbios_vpstate_entry(struct nvkm_bios *b, struct nvbios_vpstate_header *h,
                     u8 idx, struct nvbios_vpstate_entry *e)
{
        u32 offset;

        if (!e || !h || idx > h->ecount)
                return -EINVAL;

        offset = h->offset + h->hlen + idx * (h->elen + (h->slen * h->scount));
        e->pstate    = nvbios_rd08(b, offset);
        e->clock_mhz = nvbios_rd16(b, offset + 0x5);
        return 0;
}