/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2006, 2008 Stanislav Sedov <stas@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/cdefs.h>
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <err.h>
#include <errno.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <sys/ioctl.h>
#include <sys/ioccom.h>
#include <sys/cpuctl.h>

#include <machine/cpufunc.h>
#include <machine/specialreg.h>

#include "cpucontrol.h"
#include "intel.h"

#define DEFAULT_UCODE_SIZE      2000 /* Size of update data if not specified. */

int
intel_probe(int fd)
{
        char vendor[13];
        int error;
        cpuctl_cpuid_args_t idargs = {
                .level  = 0,
        };

        error = ioctl(fd, CPUCTL_CPUID, &idargs);
        if (error < 0) {
                WARN(0, "ioctl()");
                return (1);
        }
        ((uint32_t *)vendor)[0] = idargs.data[1];
        ((uint32_t *)vendor)[1] = idargs.data[3];
        ((uint32_t *)vendor)[2] = idargs.data[2];
        vendor[12] = '\0';
        if (strncmp(vendor, INTEL_VENDOR_ID, sizeof(INTEL_VENDOR_ID)) != 0)
                return (1);
        return (0);
}

void
intel_update(const struct ucode_update_params *params)
{
        int devfd;
        const char *dev, *path;
        const uint32_t *fw_image;
        int have_ext_table;
        uint32_t sum;
        unsigned int i;
        size_t payload_size;
        const intel_fw_header_t *fw_header;
        const intel_cpu_signature_t *ext_table;
        const intel_ext_header_t *ext_header;
        uint32_t sig, signature, flags;
        int32_t revision;
        ssize_t ext_size;
        size_t ext_table_size;
        const void *fw_data;
        size_t data_size, total_size;
        cpuctl_msr_args_t msrargs = {
                .msr = MSR_BIOS_SIGN,
                .data = 0,
        };
        cpuctl_cpuid_args_t idargs = {
                .level  = 1,    /* Signature. */
        };
        cpuctl_update_args_t args;
        int error;

        dev = params->dev_path;
        path = params->fw_path;
        devfd = params->devfd;
        fw_image = params->fwimage;

        assert(path);
        assert(dev);

        ext_table = NULL;
        ext_header = NULL;

        error = ioctl(devfd, CPUCTL_WRMSR, &msrargs);
        if (error < 0) {
                WARN(0, "ioctl(%s)", dev);
                goto fail;
        }
        error = ioctl(devfd, CPUCTL_CPUID, &idargs);
        if (error < 0) {
                WARN(0, "ioctl(%s)", dev);
                goto fail;
        }
        signature = idargs.data[0];
        msrargs.msr = MSR_IA32_PLATFORM_ID;
        error = ioctl(devfd, CPUCTL_RDMSR, &msrargs);
        if (error < 0) {
                WARN(0, "ioctl(%s)", dev);
                goto fail;
        }

        /*
         * MSR_IA32_PLATFORM_ID contains flag in BCD in bits 52-50.
         */
        flags = 1 << ((msrargs.data >> 50) & 7);
        msrargs.msr = MSR_BIOS_SIGN;
        error = ioctl(devfd, CPUCTL_RDMSR, &msrargs);
        if (error < 0) {
                WARN(0, "ioctl(%s)", dev);
                goto fail;
        }
        revision = msrargs.data >> 32; /* Revision in the high dword. */
        WARNX(2, "found cpu type %#x family %#x model %#x stepping %#x.",
            (signature >> 12) & 0x03, (signature >> 8) & 0x0f,
            (signature >> 4) & 0x0f, (signature >> 0) & 0x0f);
        /*
         * Open firmware image.
         */
        if (params->fwsize < sizeof(*fw_header)) {
                WARNX(2, "file too short: %s", path);
                goto fail;
        }

        fw_header = (const intel_fw_header_t *)fw_image;
        if (fw_header->header_version != INTEL_HEADER_VERSION ||
            fw_header->loader_revision != INTEL_LOADER_REVISION) {
                WARNX(2, "%s is not a valid intel firmware: version mismatch",
                    path);
                goto fail;
        }
        /*
         * According to spec, if data_size == 0, then size of ucode = 2000.
         */
        if (fw_header->data_size == 0)
                data_size = DEFAULT_UCODE_SIZE;
        else
                data_size = fw_header->data_size;
        if (fw_header->total_size == 0)
                total_size = data_size + sizeof(*fw_header);
        else
                total_size = fw_header->total_size;
        if (total_size > params->fwsize) {
                WARNX(2, "file too short: %s", path);
                goto fail;
        }
        payload_size = data_size + sizeof(*fw_header);

        /*
         * Check the primary checksum.
         */
        sum = 0;
        for (i = 0; i < (payload_size / sizeof(uint32_t)); i++)
                sum += *((const uint32_t *)fw_image + i);
        if (sum != 0) {
                WARNX(2, "%s: update data checksum invalid", path);
                goto fail;
        }

        /*
         * Check if there is an extended signature table.
         */
        ext_size = total_size - payload_size;
        have_ext_table = 0;

        if (ext_size > (signed)sizeof(*ext_header)) {
                ext_header = (const intel_ext_header_t *)
                    ((const char *)fw_image + payload_size);
                ext_table = (const intel_cpu_signature_t *)(ext_header + 1);

                /*
                 * Check the extended table size.
                 */
                ext_table_size = sizeof(*ext_header) +
                    ext_header->sig_count * sizeof(*ext_table);
                if (ext_table_size + payload_size > total_size) {
                        WARNX(2, "%s: broken extended signature table", path);
                        goto no_table;
                }

                /*
                 * Check the extended table signature.
                 */
                sum = 0;
                for (i = 0; i < (ext_table_size / sizeof(uint32_t)); i++)
                        sum += *((const uint32_t *)ext_header + i);
                if (sum != 0) {
                        WARNX(2,
                            "%s: extended signature table checksum invalid",
                            path);
                        goto no_table;
                }
                have_ext_table = 1;
        }

no_table:
        fw_data = fw_header + 1; /* Pointer to the update data. */

        /*
         * Check if the given image is ok for this cpu.
         */
        if (signature == fw_header->cpu_signature &&
            (flags & fw_header->cpu_flags) != 0)
                goto matched;
        else if (have_ext_table != 0) {
                for (i = 0; i < ext_header->sig_count; i++) {
                        sig = ext_table[i].cpu_signature;
                        if (signature == sig &&
                            (flags & ext_table[i].cpu_flags) != 0)
                                goto matched;
                }
        }
        goto fail;

matched:
        if (revision >= fw_header->revision) {
                WARNX(1, "skipping %s of rev %#x: up to date",
                    path, fw_header->revision);
                goto fail;
        }
        fprintf(stderr, "%s: updating cpu %s from rev %#x to rev %#x... ",
            path, dev, revision, fw_header->revision);
        args.data = __DECONST(void *, fw_data);
        args.size = data_size;
        error = ioctl(devfd, CPUCTL_UPDATE, &args);
        if (error < 0) {
                error = errno;
                fprintf(stderr, "failed.\n");
                errno = error;
                WARN(0, "ioctl()");
                goto fail;
        }
        fprintf(stderr, "done.\n");

fail:
        return;
}