/*-
 * Copyright (c) 2005-2009 Jung-uk Kim <jkim@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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
 *
 * $FreeBSD: src/sys/boot/i386/libi386/smbios.c,v 1.10 2009/04/07 17:58:15 jkim Exp $
 */

#include <stand.h>
#include <bootstrap.h>
#include <sys/endian.h>

#ifdef EFI
/* In EFI, we don't need PTOV(). */
#define PTOV(x)         (caddr_t)(uintptr_t)(x)
#else
#include "btxv86.h"
#endif
#include "smbios.h"

/*
 * Detect SMBIOS and export information about the SMBIOS into the
 * environment.
 *
 * System Management BIOS Reference Specification, v2.6 Final
 * http://www.dmtf.org/standards/published_documents/DSP0134_2.6.0.pdf
 */

/*
 * 2.1.1 SMBIOS Structure Table Entry Point
 *
 * "On non-EFI systems, the SMBIOS Entry Point structure, described below, can
 * be located by application software by searching for the anchor-string on
 * paragraph (16-byte) boundaries within the physical memory address range
 * 000F0000h to 000FFFFFh. This entry point encapsulates an intermediate anchor
 * string that is used by some existing DMI browsers."
 */
#define SMBIOS_START            0xf0000
#define SMBIOS_LENGTH           0x10000
#define SMBIOS_STEP             0x10
#define SMBIOS_SIG              "_SM_"
#define SMBIOS_DMI_SIG          "_DMI_"

#define SMBIOS_GET8(base, off)  (*(uint8_t *)((base) + (off)))
#define SMBIOS_GET16(base, off) (*(uint16_t *)((base) + (off)))
#define SMBIOS_GET32(base, off) (*(uint32_t *)((base) + (off)))

#define SMBIOS_GETLEN(base)     SMBIOS_GET8(base, 0x01)
#define SMBIOS_GETSTR(base)     ((base) + SMBIOS_GETLEN(base))

static uint32_t smbios_enabled_memory = 0;
static uint32_t smbios_old_enabled_memory = 0;
static uint8_t  smbios_enabled_sockets = 0;
static uint8_t  smbios_populated_sockets = 0;

static uint8_t
smbios_checksum(const caddr_t addr, const uint8_t len)
{
        uint8_t         sum;
        int             i;

        for (sum = 0, i = 0; i < len; i++)
                sum += SMBIOS_GET8(addr, i);
        return (sum);
}

static caddr_t
smbios_sigsearch(const caddr_t addr, const uint32_t len)
{
        caddr_t         cp;

        /* Search on 16-byte boundaries. */
        for (cp = addr; cp < addr + len; cp += SMBIOS_STEP)
                if (strncmp(cp, SMBIOS_SIG, 4) == 0 &&
                    smbios_checksum(cp, SMBIOS_GET8(cp, 0x05)) == 0 &&
                    strncmp(cp + 0x10, SMBIOS_DMI_SIG, 5) == 0 &&
                    smbios_checksum(cp + 0x10, 0x0f) == 0)
                        return (cp);
        return (NULL);
}

static void
smbios_setenv(const char *name, caddr_t addr, const int offset)
{
        caddr_t         cp;
        int             i, idx;

        idx = SMBIOS_GET8(addr, offset);
        if (idx != 0) {
                cp = SMBIOS_GETSTR(addr);
                for (i = 1; i < idx; i++)
                        cp += strlen(cp) + 1;
                setenv(name, cp, 1);
        }
}

#ifdef SMBIOS_SERIAL_NUMBERS

#define UUID_SIZE               16
#define UUID_TYPE               uint32_t
#define UUID_STEP               sizeof(UUID_TYPE)
#define UUID_ALL_BITS           (UUID_SIZE / UUID_STEP)
#define UUID_GET(base, off)     (*(UUID_TYPE *)((base) + (off)))

static void
smbios_setuuid(const char *name, const caddr_t addr, const int ver)
{
        char            uuid[37];
        int             i, ones, zeros;
        UUID_TYPE       n;
        uint32_t        f1;
        uint16_t        f2, f3;

        for (i = 0, ones = 0, zeros = 0; i < UUID_SIZE; i += UUID_STEP) {
                n = UUID_GET(addr, i) + 1;
                if (zeros == 0 && n == 0)
                        ones++;
                else if (ones == 0 && n == 1)
                        zeros++;
                else
                        break;
        }

        if (ones != UUID_ALL_BITS && zeros != UUID_ALL_BITS) {
                /*
                 * 3.3.2.1 System UUID
                 *
                 * "Although RFC 4122 recommends network byte order for all
                 * fields, the PC industry (including the ACPI, UEFI, and
                 * Microsoft specifications) has consistently used
                 * little-endian byte encoding for the first three fields:
                 * time_low, time_mid, time_hi_and_version. The same encoding,
                 * also known as wire format, should also be used for the
                 * SMBIOS representation of the UUID."
                 *
                 * Note: We use network byte order for backward compatibility
                 * unless SMBIOS version is 2.6+ or little-endian is forced.
                 */
#ifndef SMBIOS_LITTLE_ENDIAN_UUID
                if (ver < 0x0206) {
                        f1 = ntohl(SMBIOS_GET32(addr, 0));
                        f2 = ntohs(SMBIOS_GET16(addr, 4));
                        f3 = ntohs(SMBIOS_GET16(addr, 6));
                } else
#endif
                {
                        f1 = le32toh(SMBIOS_GET32(addr, 0));
                        f2 = le16toh(SMBIOS_GET16(addr, 4));
                        f3 = le16toh(SMBIOS_GET16(addr, 6));
                }
                sprintf(uuid,
                    "%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",
                    f1, f2, f3, SMBIOS_GET8(addr, 8), SMBIOS_GET8(addr, 9),
                    SMBIOS_GET8(addr, 10), SMBIOS_GET8(addr, 11),
                    SMBIOS_GET8(addr, 12), SMBIOS_GET8(addr, 13),
                    SMBIOS_GET8(addr, 14), SMBIOS_GET8(addr, 15));
                setenv(name, uuid, 1);
        }
}

#undef UUID_SIZE
#undef UUID_TYPE
#undef UUID_STEP
#undef UUID_ALL_BITS
#undef UUID_GET

#endif

static caddr_t
smbios_parse_table(const caddr_t addr, const int ver)
{
        caddr_t         cp;
        int             proc, size, osize, type;

        type = SMBIOS_GET8(addr, 0);    /* 3.1.2 Structure Header Format */
        switch(type) {
        case 0:         /* 3.3.1 BIOS Information (Type 0) */
                smbios_setenv("smbios.bios.vendor", addr, 0x04);
                smbios_setenv("smbios.bios.version", addr, 0x05);
                smbios_setenv("smbios.bios.reldate", addr, 0x08);
                break;

        case 1:         /* 3.3.2 System Information (Type 1) */
                smbios_setenv("smbios.system.maker", addr, 0x04);
                smbios_setenv("smbios.system.product", addr, 0x05);
                smbios_setenv("smbios.system.version", addr, 0x06);
#ifdef SMBIOS_SERIAL_NUMBERS
                smbios_setenv("smbios.system.serial", addr, 0x07);
                smbios_setuuid("smbios.system.uuid", addr + 0x08, ver);
#endif
                break;

        case 2:         /* 3.3.3 Base Board (or Module) Information (Type 2) */
                smbios_setenv("smbios.planar.maker", addr, 0x04);
                smbios_setenv("smbios.planar.product", addr, 0x05);
                smbios_setenv("smbios.planar.version", addr, 0x06);
#ifdef SMBIOS_SERIAL_NUMBERS
                smbios_setenv("smbios.planar.serial", addr, 0x07);
#endif
                break;

        case 3:         /* 3.3.4 System Enclosure or Chassis (Type 3) */
                smbios_setenv("smbios.chassis.maker", addr, 0x04);
                smbios_setenv("smbios.chassis.version", addr, 0x06);
#ifdef SMBIOS_SERIAL_NUMBERS
                smbios_setenv("smbios.chassis.serial", addr, 0x07);
                smbios_setenv("smbios.chassis.tag", addr, 0x08);
#endif
                break;

        case 4:         /* 3.3.5 Processor Information (Type 4) */
                /*
                 * Offset 18h: Processor Status
                 *
                 * Bit 7        Reserved, must be 0
                 * Bit 6        CPU Socket Populated
                 *              1 - CPU Socket Populated
                 *              0 - CPU Socket Unpopulated
                 * Bit 5:3      Reserved, must be zero
                 * Bit 2:0      CPU Status
                 *              0h - Unknown
                 *              1h - CPU Enabled
                 *              2h - CPU Disabled by User via BIOS Setup
                 *              3h - CPU Disabled by BIOS (POST Error)
                 *              4h - CPU is Idle, waiting to be enabled
                 *              5-6h - Reserved
                 *              7h - Other
                 */
                proc = SMBIOS_GET8(addr, 0x18);
                if ((proc & 0x07) == 1)
                        smbios_enabled_sockets++;
                if ((proc & 0x40) != 0)
                        smbios_populated_sockets++;
                break;

        case 6:         /* 3.3.7 Memory Module Information (Type 6, Obsolete) */
                /*
                 * Offset 0Ah: Enabled Size
                 *
                 * Bit 7        Bank connection
                 *              1 - Double-bank connection
                 *              0 - Single-bank connection
                 * Bit 6:0      Size (n), where 2**n is the size in MB
                 *              7Dh - Not determinable (Installed Size only)
                 *              7Eh - Module is installed, but no memory
                 *                    has been enabled
                 *              7Fh - Not installed
                 */
                osize = SMBIOS_GET8(addr, 0x0a) & 0x7f;
                if (osize > 0 && osize < 22)
                        smbios_old_enabled_memory += 1 << (osize + 10);
                break;

        case 17:        /* 3.3.18 Memory Device (Type 17) */
                /*
                 * Offset 0Ch: Size
                 *
                 * Bit 15       Granularity
                 *              1 - Value is in kilobytes units
                 *              0 - Value is in megabytes units
                 * Bit 14:0     Size
                 */
                size = SMBIOS_GET16(addr, 0x0c);
                if (size != 0 && size != 0xffff)
                        smbios_enabled_memory += (size & 0x8000) != 0 ?
                            (size & 0x7fff) : (size << 10);
                break;

        default:        /* skip other types */
                break;
        }

        /* Find structure terminator. */
        cp = SMBIOS_GETSTR(addr);
        while (SMBIOS_GET16(cp, 0) != 0)
                cp++;

        return (cp + 2);
}

void
smbios_detect(const caddr_t addr)
{
        char            buf[32];
        caddr_t         vaddr, dmi, smbios;
        size_t          count, length;
        uint32_t        paddr;
        int             major, minor, ver;
        unsigned int    i;

        /* Search signatures and validate checksums. */
        smbios = smbios_sigsearch(addr ? addr : PTOV(SMBIOS_START),
            SMBIOS_LENGTH);
        if (smbios == NULL)
                return;

        /*
         * Export the SMBIOS entry point via kenv so that the SMBIOS table can
         * be found (e.g., by dmidecode(8)) in UEFI-only mode, where the BIOS
         * is not mapped into the standard address space.
         */
        sprintf(buf, "%p", smbios);
        setenv("hint.smbios.0.mem", buf, 1);

        length = SMBIOS_GET16(smbios, 0x16);    /* Structure Table Length */
        paddr = SMBIOS_GET32(smbios, 0x18);     /* Structure Table Address */
        count = SMBIOS_GET16(smbios, 0x1c);     /* No of SMBIOS Structures */
        ver = SMBIOS_GET8(smbios, 0x1e);        /* SMBIOS BCD Revision */

        if (ver != 0) {
                major = ver >> 4;
                minor = ver & 0x0f;
                if (major > 9 || minor > 9)
                        ver = 0;
        }
        if (ver == 0) {
                major = SMBIOS_GET8(smbios, 0x06); /* SMBIOS Major Version */
                minor = SMBIOS_GET8(smbios, 0x07); /* SMBIOS Minor Version */
        }
        ver = (major << 8) | minor;

        vaddr = PTOV(paddr);
        for (dmi = vaddr, i = 0; dmi < vaddr + length && i < count; i++)
                dmi = smbios_parse_table(dmi, ver);

        sprintf(buf, "%d.%d", major, minor);
        setenv("smbios.version", buf, 1);
        if (smbios_enabled_memory > 0 || smbios_old_enabled_memory > 0) {
                sprintf(buf, "%u", smbios_enabled_memory > 0 ?
                    smbios_enabled_memory : smbios_old_enabled_memory);
                setenv("smbios.memory.enabled", buf, 1);
        }
        if (smbios_enabled_sockets > 0) {
                sprintf(buf, "%u", smbios_enabled_sockets);
                setenv("smbios.socket.enabled", buf, 1);
        }
        if (smbios_populated_sockets > 0) {
                sprintf(buf, "%u", smbios_populated_sockets);
                setenv("smbios.socket.populated", buf, 1);
        }
}