pc.c

xen虚拟机源代码安装包

/*
 * QEMU PC System Emulator
 * 
 * Copyright (c) 2003-2004 Fabrice Bellard
 * 
 * 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 AUTHORS OR COPYRIGHT HOLDERS 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.
 */
#include "vl.h"

/* output Bochs bios info messages */
//#define DEBUG_BIOS

#define BIOS_FILENAME "bios.bin"
#define VGABIOS_FILENAME "vgabios.bin"
#define VGABIOS_CIRRUS_FILENAME "vgabios-cirrus.bin"
#define LINUX_BOOT_FILENAME "linux_boot.bin"

static fdctrl_t *floppy_controller;
static RTCState *rtc_state;
#ifndef CONFIG_DM
static PITState *pit;
#endif /* !CONFIG_DM */
#ifndef CONFIG_DM
static IOAPICState *ioapic;
#endif /* !CONFIG_DM */
static PCIDevice *i440fx_state;

static void ioport80_write(void *opaque, uint32_t addr, uint32_t data)
{
}

/* MSDOS compatibility mode FPU exception support */
/* XXX: add IGNNE support */
void cpu_set_ferr(CPUX86State *s)
{
    pic_set_irq(13, 1);
}

static void ioportF0_write(void *opaque, uint32_t addr, uint32_t data)
{
    pic_set_irq(13, 0);
}

/* TSC handling */
uint64_t cpu_get_tsc(CPUX86State *env)
{
    /* Note: when using kqemu, it is more logical to return the host TSC
       because kqemu does not trap the RDTSC instruction for
       performance reasons */
#if USE_KQEMU
    if (env->kqemu_enabled) {
        return cpu_get_real_ticks();
    } else 
#endif
    {
        return cpu_get_ticks();
    }
}

#ifndef CONFIG_DM
/* SMM support */
void cpu_smm_update(CPUState *env)
{
    if (i440fx_state && env == first_cpu)
        i440fx_set_smm(i440fx_state, (env->hflags >> HF_SMM_SHIFT) & 1);
}


/* IRQ handling */
int cpu_get_pic_interrupt(CPUState *env)
{
    int intno;

    intno = apic_get_interrupt(env);
    if (intno >= 0) {
        /* set irq request if a PIC irq is still pending */
        /* XXX: improve that */
        pic_update_irq(isa_pic); 
        return intno;
    }
    /* read the irq from the PIC */
    intno = pic_read_irq(isa_pic);
    return intno;
}
#endif /* CONFIG_DM */

static void pic_irq_request(void *opaque, int level)
{
    CPUState *env = opaque;
    if (level)
        cpu_interrupt(env, CPU_INTERRUPT_HARD);
    else
        cpu_reset_interrupt(env, CPU_INTERRUPT_HARD);
}

/* PC cmos mappings */

#define REG_EQUIPMENT_BYTE          0x14

static int cmos_get_fd_drive_type(int fd0)
{
    int val;

    switch (fd0) {
    case 0:
        /* 1.44 Mb 3"5 drive */
        val = 4;
        break;
    case 1:
        /* 2.88 Mb 3"5 drive */
        val = 5;
        break;
    case 2:
        /* 1.2 Mb 5"5 drive */
        val = 2;
        break;
    default:
        val = 0;
        break;
    }
    return val;
}

static void cmos_init_hd(int type_ofs, int info_ofs, BlockDriverState *hd) 
{
    RTCState *s = rtc_state;
    int cylinders, heads, sectors;
    bdrv_get_geometry_hint(hd, &cylinders, &heads, &sectors);
    rtc_set_memory(s, type_ofs, 47);
    rtc_set_memory(s, info_ofs, cylinders);
    rtc_set_memory(s, info_ofs + 1, cylinders >> 8);
    rtc_set_memory(s, info_ofs + 2, heads);
    rtc_set_memory(s, info_ofs + 3, 0xff);
    rtc_set_memory(s, info_ofs + 4, 0xff);
    rtc_set_memory(s, info_ofs + 5, 0xc0 | ((heads > 8) << 3));
    rtc_set_memory(s, info_ofs + 6, cylinders);
    rtc_set_memory(s, info_ofs + 7, cylinders >> 8);
    rtc_set_memory(s, info_ofs + 8, sectors);
}

static int get_bios_disk(char *boot_device, int index) {

    if (index < strlen(boot_device)) {
        switch (boot_device[index]) {
        case 'a':
            return 0x01;            /* floppy */
        case 'c':
            return 0x02;            /* hard drive */
        case 'd':
            return 0x03;            /* cdrom */
        case 'n':
            return 0x04;            /* network */
        }
    }
    return 0x00;                /* no device */
}

/* hd_table must contain 4 block drivers */
static void cmos_init(uint64_t ram_size, char *boot_device, BlockDriverState **hd_table)
{
    RTCState *s = rtc_state;
    int val;
    int fd0, fd1, nb;
    int i;

    /* various important CMOS locations needed by PC/Bochs bios */

    /* memory size */
    val = 640; /* base memory in K */
    rtc_set_memory(s, 0x15, val);
    rtc_set_memory(s, 0x16, val >> 8);

    val = (ram_size / 1024) - 1024;
    if (val > 65535)
        val = 65535;
    rtc_set_memory(s, 0x17, val);
    rtc_set_memory(s, 0x18, val >> 8);
    rtc_set_memory(s, 0x30, val);
    rtc_set_memory(s, 0x31, val >> 8);

    if (ram_size > (16 * 1024 * 1024))
        val = (ram_size / 65536) - ((16 * 1024 * 1024) / 65536);
    else
        val = 0;
    if (val > 65535)
        val = 65535;
    rtc_set_memory(s, 0x34, val);
    rtc_set_memory(s, 0x35, val >> 8);
    
    if (boot_device == NULL) {
        /* default to hd, then cd, then floppy. */
        boot_device = "cda";
    }
    rtc_set_memory(s, 0x3d, get_bios_disk(boot_device, 0) |
                   (get_bios_disk(boot_device, 1) << 4));
    rtc_set_memory(s, 0x38, (get_bios_disk(boot_device, 2) << 4) |
                   (!fd_bootchk ? 0x01 : 0x00));

    /* floppy type */

    fd0 = fdctrl_get_drive_type(floppy_controller, 0);
    fd1 = fdctrl_get_drive_type(floppy_controller, 1);

    val = (cmos_get_fd_drive_type(fd0) << 4) | cmos_get_fd_drive_type(fd1);
    rtc_set_memory(s, 0x10, val);
    
    val = 0;
    nb = 0;
    if (fd0 < 3)
        nb++;
    if (fd1 < 3)
        nb++;
    switch (nb) {
    case 0:
        break;
    case 1:
        val |= 0x01; /* 1 drive, ready for boot */
        break;
    case 2:
        val |= 0x41; /* 2 drives, ready for boot */
        break;
    }
    val |= 0x02; /* FPU is there */
    val |= 0x04; /* PS/2 mouse installed */
    rtc_set_memory(s, REG_EQUIPMENT_BYTE, val);

    /* hard drives */

    rtc_set_memory(s, 0x12, (hd_table[0] ? 0xf0 : 0) | (hd_table[1] ? 0x0f : 0));
    if (hd_table[0])
        cmos_init_hd(0x19, 0x1b, hd_table[0]);
    if (hd_table[1]) 
        cmos_init_hd(0x1a, 0x24, hd_table[1]);

    val = 0;
    for (i = 0; i < 4; i++) {
        if (hd_table[i]) {
            int cylinders, heads, sectors, translation;
            /* NOTE: bdrv_get_geometry_hint() returns the physical
                geometry.  It is always such that: 1 <= sects <= 63, 1
                <= heads <= 16, 1 <= cylinders <= 16383. The BIOS
                geometry can be different if a translation is done. */
            translation = bdrv_get_translation_hint(hd_table[i]);
            if (translation == BIOS_ATA_TRANSLATION_AUTO) {
                bdrv_get_geometry_hint(hd_table[i], &cylinders, &heads, &sectors);
                if (cylinders <= 1024 && heads <= 16 && sectors <= 63) {
                    /* No translation. */
                    translation = 0;
                } else {
                    /* LBA translation. */
                    translation = 1;
                }
            } else {
                translation--;
            }
            val |= translation << (i * 2);
        }
    }
    rtc_set_memory(s, 0x39, val);
}

void ioport_set_a20(int enable)
{
    /* XXX: send to all CPUs ? */
    cpu_x86_set_a20(first_cpu, enable);
}

int ioport_get_a20(void)
{
    return ((first_cpu->a20_mask >> 20) & 1);
}

static void ioport92_write(void *opaque, uint32_t addr, uint32_t val)
{
    ioport_set_a20((val >> 1) & 1);
    /* XXX: bit 0 is fast reset */
}

static uint32_t ioport92_read(void *opaque, uint32_t addr)
{
    return ioport_get_a20() << 1;
}

/***********************************************************/
/* Bochs BIOS debug ports */

void bochs_bios_write(void *opaque, uint32_t addr, uint32_t val)
{
    static const char shutdown_str[8] = "Shutdown";
    static int shutdown_index = 0;
    
    switch(addr) {
        /* Bochs BIOS messages */
    case 0x400:
    case 0x401:
        fprintf(stderr, "BIOS panic at rombios.c, line %d\n", val);
        exit(1);
    case 0x402:
    case 0x403:
#ifdef DEBUG_BIOS
        fprintf(stderr, "%c", val);
#endif
        break;
    case 0x8900:
        /* same as Bochs power off */
        if (val == shutdown_str[shutdown_index]) {
            shutdown_index++;
            if (shutdown_index == 8) {
                shutdown_index = 0;
                qemu_system_shutdown_request();
            }
        } else {
            shutdown_index = 0;
        }
        break;

        /* LGPL'ed VGA BIOS messages */
    case 0x501:
    case 0x502:
        fprintf(stderr, "VGA BIOS panic, line %d\n", val);
        exit(1);
    case 0x500:
    case 0x503:
#ifdef DEBUG_BIOS
        fprintf(stderr, "%c", val);
#endif
        break;
    }
}

void bochs_bios_init(void)
{
    register_ioport_write(0x400, 1, 2, bochs_bios_write, NULL);
    register_ioport_write(0x401, 1, 2, bochs_bios_write, NULL);
    register_ioport_write(0x402, 1, 1, bochs_bios_write, NULL);
    register_ioport_write(0x403, 1, 1, bochs_bios_write, NULL);
    register_ioport_write(0x8900, 1, 1, bochs_bios_write, NULL);

    register_ioport_write(0x501, 1, 2, bochs_bios_write, NULL);
    register_ioport_write(0x502, 1, 2, bochs_bios_write, NULL);
    register_ioport_write(0x500, 1, 1, bochs_bios_write, NULL);
    register_ioport_write(0x503, 1, 1, bochs_bios_write, NULL);
}

#if defined(__i386__) || defined(__x86_64__)
/* Generate an initial boot sector which sets state and jump to
   a specified vector */
static void generate_bootsect(uint32_t gpr[8], uint16_t segs[6], uint16_t ip)
{
    uint8_t bootsect[512], *p;
    int i;

    if (bs_table[0] == NULL) {
        fprintf(stderr, "A disk image must be given for 'hda' when booting "
                "a Linux kernel\n");
        exit(1);
    }

    memset(bootsect, 0, sizeof(bootsect));

    /* Copy the MSDOS partition table if possible */
    bdrv_read(bs_table[0], 0, bootsect, 1);

    /* Make sure we have a partition signature */
    bootsect[510] = 0x55;
    bootsect[511] = 0xaa;