/*
 * 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 "mxms.h"

#define ROM16(x) get_unaligned_le16(&(x))
#define ROM32(x) get_unaligned_le32(&(x))

static u8 *
mxms_data(struct nvkm_mxm *mxm)
{
        return mxm->mxms;

}

u16
mxms_version(struct nvkm_mxm *mxm)
{
        u8 *mxms = mxms_data(mxm);
        u16 version = (mxms[4] << 8) | mxms[5];
        switch (version ) {
        case 0x0200:
        case 0x0201:
        case 0x0300:
                return version;
        default:
                break;
        }

        nvkm_debug(&mxm->subdev, "unknown version %d.%d\n", mxms[4], mxms[5]);
        return 0x0000;
}

u16
mxms_headerlen(struct nvkm_mxm *mxm)
{
        return 8;
}

u16
mxms_structlen(struct nvkm_mxm *mxm)
{
        return *(u16 *)&mxms_data(mxm)[6];
}

bool
mxms_checksum(struct nvkm_mxm *mxm)
{
        u16 size = mxms_headerlen(mxm) + mxms_structlen(mxm);
        u8 *mxms = mxms_data(mxm), sum = 0;
        while (size--)
                sum += *mxms++;
        if (sum) {
                nvkm_debug(&mxm->subdev, "checksum invalid\n");
                return false;
        }
        return true;
}

bool
mxms_valid(struct nvkm_mxm *mxm)
{
        u8 *mxms = mxms_data(mxm);
        if (*(u32 *)mxms != 0x5f4d584d) {
                nvkm_debug(&mxm->subdev, "signature invalid\n");
                return false;
        }

        if (!mxms_version(mxm) || !mxms_checksum(mxm))
                return false;

        return true;
}

bool
mxms_foreach(struct nvkm_mxm *mxm, u8 types,
             bool (*exec)(struct nvkm_mxm *, u8 *, void *), void *info)
{
        struct nvkm_subdev *subdev = &mxm->subdev;
        u8 *mxms = mxms_data(mxm);
        u8 *desc = mxms + mxms_headerlen(mxm);
        u8 *fini = desc + mxms_structlen(mxm) - 1;
        while (desc < fini) {
                u8 type = desc[0] & 0x0f;
                u8 headerlen = 0;
                u8 recordlen = 0;
                u8 entries = 0;

                switch (type) {
                case 0: /* Output Device Structure */
                        if (mxms_version(mxm) >= 0x0300)
                                headerlen = 8;
                        else
                                headerlen = 6;
                        break;
                case 1: /* System Cooling Capability Structure */
                case 2: /* Thermal Structure */
                case 3: /* Input Power Structure */
                        headerlen = 4;
                        break;
                case 4: /* GPIO Device Structure */
                        headerlen = 4;
                        recordlen = 2;
                        entries   = (ROM32(desc[0]) & 0x01f00000) >> 20;
                        break;
                case 5: /* Vendor Specific Structure */
                        headerlen = 8;
                        break;
                case 6: /* Backlight Control Structure */
                        if (mxms_version(mxm) >= 0x0300) {
                                headerlen = 4;
                                recordlen = 8;
                                entries   = (desc[1] & 0xf0) >> 4;
                        } else {
                                headerlen = 8;
                        }
                        break;
                case 7: /* Fan Control Structure */
                        headerlen = 8;
                        recordlen = 4;
                        entries   = desc[1] & 0x07;
                        break;
                default:
                        nvkm_debug(subdev, "unknown descriptor type %d\n", type);
                        return false;
                }

                if (mxm->subdev.debug >= NV_DBG_DEBUG && (exec == NULL)) {
                        static const char * mxms_desc[] = {
                                "ODS", "SCCS", "TS", "IPS",
                                "GSD", "VSS", "BCS", "FCS",
                        };
                        u8 *dump = desc;
                        char data[32], *ptr;
                        int i, j;

                        for (j = headerlen - 1, ptr = data; j >= 0; j--)
                                ptr += sprintf(ptr, "%02x", dump[j]);
                        dump += headerlen;

                        nvkm_debug(subdev, "%4s: %s\n", mxms_desc[type], data);
                        for (i = 0; i < entries; i++, dump += recordlen) {
                                for (j = recordlen - 1, ptr = data; j >= 0; j--)
                                        ptr += sprintf(ptr, "%02x", dump[j]);
                                nvkm_debug(subdev, "      %s\n", data);
                        }
                }

                if (types & (1 << type)) {
                        if (!exec(mxm, desc, info))
                                return false;
                }

                desc += headerlen + (entries * recordlen);
        }

        return true;
}

void
mxms_output_device(struct nvkm_mxm *mxm, u8 *pdata, struct mxms_odev *desc)
{
        u64 data = ROM32(pdata[0]);
        if (mxms_version(mxm) >= 0x0300)
                data |= (u64)ROM16(pdata[4]) << 32;

        desc->outp_type = (data & 0x00000000000000f0ULL) >> 4;
        desc->ddc_port  = (data & 0x0000000000000f00ULL) >> 8;
        desc->conn_type = (data & 0x000000000001f000ULL) >> 12;
        desc->dig_conn  = (data & 0x0000000000780000ULL) >> 19;
}