/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2006, 2008 Stanislav Sedov <stas@FreeBSD.org>.
 * All rights reserved.
 * Copyright (c) 2012 Andriy Gapon <avg@FreeBSD.org>.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/systm.h>

#include <x86/ucode.h>

#ifndef _KERNEL
#include <err.h>

#include "cpucontrol.h"
#endif


#ifdef _KERNEL
#define WARNX(level, ...)                                       \
        if (bootverbose) {                                      \
                printf(__VA_ARGS__);                            \
                printf("\n");                                   \
        }
#endif

/*
 * AMD family 10h and later.
 */
typedef struct amd_10h_fw_header {
        uint32_t        data_code;
        uint32_t        patch_id;
        uint16_t        mc_patch_data_id;
        uint8_t         mc_patch_data_len;
        uint8_t         init_flag;
        uint32_t        mc_patch_data_checksum;
        uint32_t        nb_dev_id;
        uint32_t        sb_dev_id;
        uint16_t        processor_rev_id;
        uint8_t         nb_rev_id;
        uint8_t         sb_rev_id;
        uint8_t         bios_api_rev;
        uint8_t         reserved1[3];
        uint32_t        match_reg[8];
} amd_10h_fw_header_t;

typedef struct equiv_cpu_entry {
        uint32_t        installed_cpu;
        uint32_t        fixed_errata_mask;
        uint32_t        fixed_errata_compare;
        uint16_t        equiv_cpu;
        uint16_t        res;
} equiv_cpu_entry_t;

typedef struct section_header {
        uint32_t        type;
        uint32_t        size;
} section_header_t;

typedef struct container_header {
        uint32_t        magic;
} container_header_t;

#define AMD_10H_MAGIC                   0x414d44
#define AMD_10H_EQUIV_TABLE_TYPE        0
#define AMD_10H_uCODE_TYPE              1

/*
 * NB: the format of microcode update files is not documented by AMD.
 * It has been reverse engineered from studying Coreboot, illumos and Linux
 * source code.
 */
const void *
ucode_amd_find(const char *path, uint32_t signature, uint32_t *revision,
    const uint8_t *fw_data, size_t fw_size, size_t *selected_sizep)
{
        const amd_10h_fw_header_t *fw_header;
        const amd_10h_fw_header_t *selected_fw;
        const equiv_cpu_entry_t *equiv_cpu_table;
        const section_header_t *section_header;
        const container_header_t *container_header;
        size_t selected_size;
        uint16_t equiv_id;
        int i;

        WARNX(1, "found cpu family %#x model %#x "
            "stepping %#x extfamily %#x extmodel %#x.",
            ((signature >> 8) & 0x0f) + ((signature >> 20) & 0xff),
            (signature >> 4) & 0x0f,
            (signature >> 0) & 0x0f, (signature >> 20) & 0xff,
            (signature >> 16) & 0x0f);
        WARNX(1, "microcode revision %#x", *revision);

nextfile:
        WARNX(1, "checking %s for update.", path);
        WARNX(3, "processing next container file");
        if (fw_size <
            (sizeof(*container_header) + sizeof(*section_header))) {
                WARNX(2, "file too short: %s", path);
                return (NULL);
        }

        container_header = (const container_header_t *)fw_data;
        if (container_header->magic != AMD_10H_MAGIC) {
                WARNX(2, "%s is not a valid amd firmware: bad magic", path);
                return (NULL);
        }
        fw_data += sizeof(*container_header);
        fw_size -= sizeof(*container_header);

        section_header = (const section_header_t *)fw_data;
        if (section_header->type != AMD_10H_EQUIV_TABLE_TYPE) {
                WARNX(2, "%s is not a valid amd firmware: "
                    "first section is not CPU equivalence table", path);
                return (NULL);
        }
        if (section_header->size == 0) {
                WARNX(2, "%s is not a valid amd firmware: "
                    "first section is empty", path);
                return (NULL);
        }
        fw_data += sizeof(*section_header);
        fw_size -= sizeof(*section_header);

        if (section_header->size > fw_size) {
                WARNX(2, "%s is not a valid amd firmware: "
                    "file is truncated", path);
                return (NULL);
        }
        if (section_header->size < sizeof(*equiv_cpu_table)) {
                WARNX(2, "%s is not a valid amd firmware: "
                    "first section is too short", path);
                return (NULL);
        }
        equiv_cpu_table = (const equiv_cpu_entry_t *)fw_data;
        fw_data += section_header->size;
        fw_size -= section_header->size;

        equiv_id = 0;
        for (i = 0; equiv_cpu_table[i].installed_cpu != 0; i++) {
                WARNX(3, "signature 0x%x i %d installed_cpu 0x%x equiv 0x%x",
                      signature, i, equiv_cpu_table[i].installed_cpu,
                      equiv_cpu_table[i].equiv_cpu);
                if (signature == equiv_cpu_table[i].installed_cpu) {
                        equiv_id = equiv_cpu_table[i].equiv_cpu;
                        WARNX(3, "equiv_id: %x, signature %8x,"
                            " equiv_cpu_table[%d] %8x", equiv_id, signature,
                            i, equiv_cpu_table[i].installed_cpu);
                        break;
                }
        }
        if (equiv_id == 0) {
                WARNX(2, "CPU is not found in the equivalence table");
        }

        while (fw_size >= sizeof(*section_header)) {
                section_header = (const section_header_t *)fw_data;
                if (section_header->type == AMD_10H_MAGIC) {
                        WARNX(2, "%s next section is actually a new container",
                            path);
                        if (selected_fw != NULL)
                                goto found;
                        else
                                goto nextfile;
                }
                fw_data += sizeof(*section_header);
                fw_size -= sizeof(*section_header);
                if (section_header->type != AMD_10H_uCODE_TYPE) {
                        WARNX(2, "%s is not a valid amd firmware: "
                            "section has incorrect type", path);
                        break;
                }
                if (section_header->size > fw_size) {
                        WARNX(2, "%s is not a valid amd firmware: "
                            "file is truncated", path);
                        break;
                }
                if (section_header->size < sizeof(*fw_header)) {
                        WARNX(2, "%s is not a valid amd firmware: "
                            "section is too short", path);
                        break;
                }
                fw_header = (const amd_10h_fw_header_t *)fw_data;
                fw_data += section_header->size;
                fw_size -= section_header->size;

                if (fw_header->processor_rev_id != equiv_id) {
                        WARNX(1, "firmware processor_rev_id %x, equiv_id %x",
                            fw_header->processor_rev_id, equiv_id);
                        continue; /* different cpu */
                }
                if (fw_header->patch_id <= *revision) {
                        WARNX(1, "patch_id %x, revision %x",
                            fw_header->patch_id, *revision);
                        continue; /* not newer revision */
                }
                if (fw_header->nb_dev_id != 0 || fw_header->sb_dev_id != 0) {
                        WARNX(2, "Chipset-specific microcode is not supported");
                }

                WARNX(3, "selecting revision: %x", fw_header->patch_id);
                *revision = fw_header->patch_id;
                selected_fw = fw_header;
                selected_size = section_header->size;
        }

        if (fw_size != 0) {
                WARNX(2, "%s is not a valid amd firmware: "
                    "file is truncated", path);
                selected_fw = NULL;
        }

found:
        *selected_sizep = selected_size;
        return (selected_fw);
}