Archipelago » qemu

/*

 *  APIC support

 * 

 *  Copyright (c) 2004-2005 Fabrice Bellard

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

#include "vl.h"

//#define DEBUG_APIC

/* APIC Local Vector Table */

#define APIC_LVT_TIMER   0

#define APIC_LVT_THERMAL 1

#define APIC_LVT_PERFORM 2

#define APIC_LVT_LINT0   3

#define APIC_LVT_LINT1   4

#define APIC_LVT_ERROR   5

#define APIC_LVT_NB      6

/* APIC delivery modes */

#define APIC_DM_FIXED	0

#define APIC_DM_LOWPRI	1

#define APIC_DM_SMI	2

#define APIC_DM_NMI	4

#define APIC_DM_INIT	5

#define APIC_DM_SIPI	6

#define APIC_DM_EXTINT	7

#define APIC_TRIGGER_EDGE  0

#define APIC_TRIGGER_LEVEL 1

#define	APIC_LVT_TIMER_PERIODIC		(1<<17)

#define	APIC_LVT_MASKED			(1<<16)

#define	APIC_LVT_LEVEL_TRIGGER		(1<<15)

#define	APIC_LVT_REMOTE_IRR		(1<<14)

#define	APIC_INPUT_POLARITY		(1<<13)

#define	APIC_SEND_PENDING		(1<<12)

#define ESR_ILLEGAL_ADDRESS (1 << 7)

#define APIC_SV_ENABLE (1 << 8)

typedef struct APICState {

    CPUState *cpu_env;

    uint32_t apicbase;

    uint8_t id;

    uint8_t tpr;

    uint32_t spurious_vec;

    uint32_t isr[8];  /* in service register */

    uint32_t tmr[8];  /* trigger mode register */

    uint32_t irr[8]; /* interrupt request register */

    uint32_t lvt[APIC_LVT_NB];

    uint32_t esr; /* error register */

    uint32_t icr[2];

    uint32_t divide_conf;

    int count_shift;

    uint32_t initial_count;

    int64_t initial_count_load_time, next_time;

    QEMUTimer *timer;

} APICState;

static int apic_io_memory;

void cpu_set_apic_base(CPUState *env, uint64_t val)

{

    APICState *s = env->apic_state;

#ifdef DEBUG_APIC

    printf("cpu_set_apic_base: %016llx\n", val);

#endif

    s->apicbase = (val & 0xfffff000) | 

        (s->apicbase & (MSR_IA32_APICBASE_BSP | MSR_IA32_APICBASE_ENABLE));

    /* if disabled, cannot be enabled again */

    if (!(val & MSR_IA32_APICBASE_ENABLE)) {

        s->apicbase &= ~MSR_IA32_APICBASE_ENABLE;

        env->cpuid_features &= ~CPUID_APIC;

        s->spurious_vec &= ~APIC_SV_ENABLE;

    }

}

uint64_t cpu_get_apic_base(CPUState *env)

{

    APICState *s = env->apic_state;

#ifdef DEBUG_APIC

    printf("cpu_get_apic_base: %016llx\n", (uint64_t)s->apicbase);

#endif

    return s->apicbase;

}

/* return -1 if no bit is set */

static int get_highest_priority_int(uint32_t *tab)

{

    int i;

    for(i = 0;i < 8; i++) {

        if (tab[i] != 0) {

            return i * 32 + ffs(tab[i]) - 1;

        }

    }

    return -1;

}

static inline void set_bit(uint32_t *tab, int index)

{

    int i, mask;

    i = index >> 5;

    mask = 1 << (index & 0x1f);

    tab[i] |= mask;

}

static inline void reset_bit(uint32_t *tab, int index)

{

    int i, mask;

    i = index >> 5;

    mask = 1 << (index & 0x1f);

    tab[i] &= ~mask;

}

static int apic_get_ppr(APICState *s)

{

    int tpr, isrv, ppr;

    tpr = (s->tpr >> 4);

    isrv = get_highest_priority_int(s->isr);

    if (isrv < 0)

        isrv = 0;

    isrv >>= 4;

    if (tpr >= isrv)

        ppr = s->tpr;

    else

        ppr = isrv << 4;

    return ppr;

}

/* signal the CPU if an irq is pending */

static void apic_update_irq(APICState *s)

{

    int irrv, isrv;

    irrv = get_highest_priority_int(s->irr);

    if (irrv < 0)

        return;

    isrv = get_highest_priority_int(s->isr);

    /* if the pending irq has less priority, we do not make a new request */

    if (isrv >= 0 && irrv >= isrv)

        return;

    cpu_interrupt(s->cpu_env, CPU_INTERRUPT_HARD);

}

static void apic_set_irq(APICState *s, int vector_num, int trigger_mode)

{

    set_bit(s->irr, vector_num);

    if (trigger_mode)

        set_bit(s->tmr, vector_num);

    else

        reset_bit(s->tmr, vector_num);

    apic_update_irq(s);

}

static void apic_eoi(APICState *s)

{

    int isrv;

    isrv = get_highest_priority_int(s->isr);

    if (isrv < 0)

        return;

    reset_bit(s->isr, isrv);

    apic_update_irq(s);

}

int apic_get_interrupt(CPUState *env)

{

    APICState *s = env->apic_state;

    int intno;

    /* if the APIC is installed or enabled, we let the 8259 handle the

       IRQs */

    if (!s)

        return -1;

    if (!(s->spurious_vec & APIC_SV_ENABLE))

        return -1;

    /* XXX: spurious IRQ handling */

    intno = get_highest_priority_int(s->irr);

    if (intno < 0)

        return -1;

    reset_bit(s->irr, intno);

    set_bit(s->isr, intno);

    apic_update_irq(s);

    return intno;

}

static uint32_t apic_get_current_count(APICState *s)

{

    int64_t d;

    uint32_t val;

    d = (qemu_get_clock(vm_clock) - s->initial_count_load_time) >> 

        s->count_shift;

    if (s->lvt[APIC_LVT_TIMER] & APIC_LVT_TIMER_PERIODIC) {

        /* periodic */

        val = s->initial_count - (d % (s->initial_count + 1));

    } else {

        if (d >= s->initial_count)

            val = 0;

        else

            val = s->initial_count - d;

    }

    return val;

}

static void apic_timer_update(APICState *s, int64_t current_time)

{

    int64_t next_time, d;

    if (!(s->lvt[APIC_LVT_TIMER] & APIC_LVT_MASKED)) {

        d = (current_time - s->initial_count_load_time) >> 

            s->count_shift;

        if (s->lvt[APIC_LVT_TIMER] & APIC_LVT_TIMER_PERIODIC) {

            d = ((d / (s->initial_count + 1)) + 1) * (s->initial_count + 1);

        } else {

            if (d >= s->initial_count)

                goto no_timer;

            d = s->initial_count + 1;

        }

        next_time = s->initial_count_load_time + (d << s->count_shift);

        qemu_mod_timer(s->timer, next_time);

        s->next_time = next_time;

    } else {

    no_timer:

        qemu_del_timer(s->timer);

    }

}

static void apic_timer(void *opaque)

{

    APICState *s = opaque;

    if (!(s->lvt[APIC_LVT_TIMER] & APIC_LVT_MASKED)) {

        apic_set_irq(s, s->lvt[APIC_LVT_TIMER] & 0xff, APIC_TRIGGER_EDGE);

    }

    apic_timer_update(s, s->next_time);

}

static uint32_t apic_mem_readb(void *opaque, target_phys_addr_t addr)

{

    return 0;

}

static uint32_t apic_mem_readw(void *opaque, target_phys_addr_t addr)

{

    return 0;

}

static void apic_mem_writeb(void *opaque, target_phys_addr_t addr, uint32_t val)

{

}

static void apic_mem_writew(void *opaque, target_phys_addr_t addr, uint32_t val)

{

}

static uint32_t apic_mem_readl(void *opaque, target_phys_addr_t addr)

{

    CPUState *env;

    APICState *s;

    uint32_t val;

    int index;

    env = cpu_single_env;

    if (!env)

        return 0;

    s = env->apic_state;

    index = (addr >> 4) & 0xff;

    switch(index) {

    case 0x02: /* id */

        val = s->id << 24;

        break;

    case 0x03: /* version */

        val = 0x11 | ((APIC_LVT_NB - 1) << 16); /* version 0x11 */

        break;

    case 0x08:

        val = s->tpr;

        break;

    case 0x0a:

        /* ppr */

        val = apic_get_ppr(s);

        break;

    case 0x0f:

        val = s->spurious_vec;

        break;

    case 0x10 ... 0x17:

        val = s->isr[index & 7];

        break;

    case 0x18 ... 0x1f:

        val = s->tmr[index & 7];

        break;

    case 0x20 ... 0x27:

        val = s->irr[index & 7];

        break;

    case 0x28:

        val = s->esr;

        break;

    case 0x32 ... 0x37:

        val = s->lvt[index - 0x32];

        break;

    case 0x30:

    case 0x31:

        val = s->icr[index & 1];

        break;

    case 0x38:

        val = s->initial_count;

        break;

    case 0x39:

        val = apic_get_current_count(s);

        break;

    case 0x3e:

        val = s->divide_conf;

        break;

    default:

        s->esr |= ESR_ILLEGAL_ADDRESS;

        val = 0;

        break;

    }

#ifdef DEBUG_APIC

    printf("APIC read: %08x = %08x\n", (uint32_t)addr, val);

#endif

    return val;

}

static void apic_mem_writel(void *opaque, target_phys_addr_t addr, uint32_t val)

{

    CPUState *env;

    APICState *s;

    int index;

    env = cpu_single_env;

    if (!env)

        return;

    s = env->apic_state;

#ifdef DEBUG_APIC

    printf("APIC write: %08x = %08x\n", (uint32_t)addr, val);

#endif

    index = (addr >> 4) & 0xff;

    switch(index) {

    case 0x02:

        s->id = (val >> 24);

        break;

    case 0x08:

        s->tpr = val;

        break;

    case 0x0b: /* EOI */

        apic_eoi(s);

        break;

    case 0x0f:

        s->spurious_vec = val & 0x1ff;

        break;

    case 0x30:

    case 0x31:

        s->icr[index & 1] = val;

        break;

    case 0x32 ... 0x37:

        {

            int n = index - 0x32;

            s->lvt[n] = val;

            if (n == APIC_LVT_TIMER)

                apic_timer_update(s, qemu_get_clock(vm_clock));

        }

        break;

    case 0x38:

        s->initial_count = val;

        s->initial_count_load_time = qemu_get_clock(vm_clock);

        apic_timer_update(s, s->initial_count_load_time);

        break;

    case 0x3e:

        {

            int v;

            s->divide_conf = val & 0xb;

            v = (s->divide_conf & 3) | ((s->divide_conf >> 1) & 4);

            s->count_shift = (v + 1) & 7;

        }

        break;

    default:

        s->esr |= ESR_ILLEGAL_ADDRESS;

        break;

    }

}

static CPUReadMemoryFunc *apic_mem_read[3] = {

    apic_mem_readb,

    apic_mem_readw,

    apic_mem_readl,

};

static CPUWriteMemoryFunc *apic_mem_write[3] = {

    apic_mem_writeb,

    apic_mem_writew,

    apic_mem_writel,

};

int apic_init(CPUState *env)

{

    APICState *s;

    int i;

    s = malloc(sizeof(APICState));

    if (!s)

        return -1;

    memset(s, 0, sizeof(*s));

    env->apic_state = s;

    s->cpu_env = env;

    s->apicbase = 0xfee00000 | 

        MSR_IA32_APICBASE_BSP | MSR_IA32_APICBASE_ENABLE;

    for(i = 0; i < APIC_LVT_NB; i++)

        s->lvt[i] = 1 << 16; /* mask LVT */

    s->spurious_vec = 0xff;

    if (apic_io_memory == 0) {

        /* NOTE: the APIC is directly connected to the CPU - it is not

           on the global memory bus. */

        apic_io_memory = cpu_register_io_memory(0, apic_mem_read, 

                                                apic_mem_write, NULL);

        cpu_register_physical_memory(s->apicbase & ~0xfff, 0x1000, apic_io_memory);

    }

    s->timer = qemu_new_timer(vm_clock, apic_timer, s);

    return 0;

}