Archipelago » qemu

/*

 * QEMU generic PPC hardware System Emulator

 * 

 * Copyright (c) 2003-2004 Jocelyn Mayer

 * 

 * 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"

#include "m48t59.h"

/*****************************************************************************/

/* PPC time base and decrementer emulation */

//#define DEBUG_TB

struct ppc_tb_t {

    /* Time base management */

    int64_t  tb_offset;    /* Compensation               */

    uint32_t tb_freq;      /* TB frequency               */

    /* Decrementer management */

    uint64_t decr_next;    /* Tick for next decr interrupt  */

    struct QEMUTimer *decr_timer;

};

static inline uint64_t cpu_ppc_get_tb (ppc_tb_t *tb_env)

{

    /* TB time in tb periods */

    return muldiv64(qemu_get_clock(vm_clock) + tb_env->tb_offset,

                    tb_env->tb_freq, ticks_per_sec);

}

uint32_t cpu_ppc_load_tbl (CPUState *env)

{

    ppc_tb_t *tb_env = env->tb_env;

    uint64_t tb;

    tb = cpu_ppc_get_tb(tb_env);

#ifdef DEBUG_TB

    {

         static int last_time;

         int now;

         now = time(NULL);

         if (last_time != now) {

             last_time = now;

             printf("%s: tb=0x%016lx %d %08lx\n",

                    __func__, tb, now, tb_env->tb_offset);

         }

    }

#endif

    return tb & 0xFFFFFFFF;

}

uint32_t cpu_ppc_load_tbu (CPUState *env)

{

    ppc_tb_t *tb_env = env->tb_env;

    uint64_t tb;

    tb = cpu_ppc_get_tb(tb_env);

#ifdef DEBUG_TB

    printf("%s: tb=0x%016lx\n", __func__, tb);

#endif

    return tb >> 32;

}

static void cpu_ppc_store_tb (ppc_tb_t *tb_env, uint64_t value)

{

    tb_env->tb_offset = muldiv64(value, ticks_per_sec, tb_env->tb_freq)

        - qemu_get_clock(vm_clock);

#ifdef DEBUG_TB

    printf("%s: tb=0x%016lx offset=%08x\n", __func__, value);

#endif

}

void cpu_ppc_store_tbu (CPUState *env, uint32_t value)

{

    ppc_tb_t *tb_env = env->tb_env;

    cpu_ppc_store_tb(tb_env,

                     ((uint64_t)value << 32) | cpu_ppc_load_tbl(env));

}

void cpu_ppc_store_tbl (CPUState *env, uint32_t value)

{

    ppc_tb_t *tb_env = env->tb_env;

    cpu_ppc_store_tb(tb_env,

                     ((uint64_t)cpu_ppc_load_tbu(env) << 32) | value);

}

uint32_t cpu_ppc_load_decr (CPUState *env)

{

    ppc_tb_t *tb_env = env->tb_env;

    uint32_t decr;

    int64_t diff;

    diff = tb_env->decr_next - qemu_get_clock(vm_clock);

    if (diff >= 0)

        decr = muldiv64(diff, tb_env->tb_freq, ticks_per_sec);

    else

        decr = -muldiv64(-diff, tb_env->tb_freq, ticks_per_sec);

#if defined(DEBUG_TB)

    printf("%s: 0x%08x\n", __func__, decr);

#endif

    return decr;

}

/* When decrementer expires,

 * all we need to do is generate or queue a CPU exception

 */

static inline void cpu_ppc_decr_excp (CPUState *env)

{

    /* Raise it */

#ifdef DEBUG_TB

    printf("raise decrementer exception\n");

#endif

    cpu_interrupt(env, CPU_INTERRUPT_TIMER);

}

static void _cpu_ppc_store_decr (CPUState *env, uint32_t decr,

                                 uint32_t value, int is_excp)

{

    ppc_tb_t *tb_env = env->tb_env;

    uint64_t now, next;

#ifdef DEBUG_TB

    printf("%s: 0x%08x => 0x%08x\n", __func__, decr, value);

#endif

    now = qemu_get_clock(vm_clock);

    next = now + muldiv64(value, ticks_per_sec, tb_env->tb_freq);

    if (is_excp)

        next += tb_env->decr_next - now;

    if (next == now)

        next++;

    tb_env->decr_next = next;

    /* Adjust timer */

    qemu_mod_timer(tb_env->decr_timer, next);

    /* If we set a negative value and the decrementer was positive,

     * raise an exception.

     */

    if ((value & 0x80000000) && !(decr & 0x80000000))

        cpu_ppc_decr_excp(env);

}

void cpu_ppc_store_decr (CPUState *env, uint32_t value)

{

    _cpu_ppc_store_decr(env, cpu_ppc_load_decr(env), value, 0);

}

static void cpu_ppc_decr_cb (void *opaque)

{

    _cpu_ppc_store_decr(opaque, 0x00000000, 0xFFFFFFFF, 1);

}

/* Set up (once) timebase frequency (in Hz) */

ppc_tb_t *cpu_ppc_tb_init (CPUState *env, uint32_t freq)

{

    ppc_tb_t *tb_env;

    tb_env = qemu_mallocz(sizeof(ppc_tb_t));

    if (tb_env == NULL)

        return NULL;

    env->tb_env = tb_env;

    if (tb_env->tb_freq == 0 || 1) {

        tb_env->tb_freq = freq;

        /* Create new timer */

        tb_env->decr_timer =

            qemu_new_timer(vm_clock, &cpu_ppc_decr_cb, env);

        /* There is a bug in  2.4 kernels:

         * if a decrementer exception is pending when it enables msr_ee,

         * it's not ready to handle it...

         */

        _cpu_ppc_store_decr(env, 0xFFFFFFFF, 0xFFFFFFFF, 0);

    }

    return tb_env;

}

#if 0

/*****************************************************************************/

/* Handle system reset (for now, just stop emulation) */

void cpu_ppc_reset (CPUState *env)

{

    printf("Reset asked... Stop emulation\n");

    abort();

}

#endif

/*****************************************************************************/

/* Debug port */

void PPC_debug_write (void *opaque, uint32_t addr, uint32_t val)

{

    addr &= 0xF;

    switch (addr) {

    case 0:

        printf("%c", val);

        break;

    case 1:

        printf("\n");

        fflush(stdout);

        break;

    case 2:

        printf("Set loglevel to %04x\n", val);

        cpu_set_log(val | 0x100);

        break;

    }

}

/*****************************************************************************/

/* NVRAM helpers */

void NVRAM_set_byte (m48t59_t *nvram, uint32_t addr, uint8_t value)

{

    m48t59_write(nvram, addr, value);

}

uint8_t NVRAM_get_byte (m48t59_t *nvram, uint32_t addr)

{

    return m48t59_read(nvram, addr);

}

void NVRAM_set_word (m48t59_t *nvram, uint32_t addr, uint16_t value)

{

    m48t59_write(nvram, addr, value >> 8);

    m48t59_write(nvram, addr + 1, value & 0xFF);

}

uint16_t NVRAM_get_word (m48t59_t *nvram, uint32_t addr)

{

    uint16_t tmp;

    tmp = m48t59_read(nvram, addr) << 8;

    tmp |= m48t59_read(nvram, addr + 1);

    return tmp;

}

void NVRAM_set_lword (m48t59_t *nvram, uint32_t addr, uint32_t value)

{

    m48t59_write(nvram, addr, value >> 24);

    m48t59_write(nvram, addr + 1, (value >> 16) & 0xFF);

    m48t59_write(nvram, addr + 2, (value >> 8) & 0xFF);

    m48t59_write(nvram, addr + 3, value & 0xFF);

}

uint32_t NVRAM_get_lword (m48t59_t *nvram, uint32_t addr)

{

    uint32_t tmp;

    tmp = m48t59_read(nvram, addr) << 24;

    tmp |= m48t59_read(nvram, addr + 1) << 16;

    tmp |= m48t59_read(nvram, addr + 2) << 8;

    tmp |= m48t59_read(nvram, addr + 3);

    return tmp;

}

void NVRAM_set_string (m48t59_t *nvram, uint32_t addr,

                       const unsigned char *str, uint32_t max)

{

    int i;

    for (i = 0; i < max && str[i] != '\0'; i++) {

        m48t59_write(nvram, addr + i, str[i]);

    }

    m48t59_write(nvram, addr + max - 1, '\0');

}

int NVRAM_get_string (m48t59_t *nvram, uint8_t *dst, uint16_t addr, int max)

{

    int i;

    memset(dst, 0, max);

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

        dst[i] = NVRAM_get_byte(nvram, addr + i);

        if (dst[i] == '\0')

            break;

    }

    return i;

}

static uint16_t NVRAM_crc_update (uint16_t prev, uint16_t value)

{

    uint16_t tmp;

    uint16_t pd, pd1, pd2;

    tmp = prev >> 8;

    pd = prev ^ value;

    pd1 = pd & 0x000F;

    pd2 = ((pd >> 4) & 0x000F) ^ pd1;

    tmp ^= (pd1 << 3) | (pd1 << 8);

    tmp ^= pd2 | (pd2 << 7) | (pd2 << 12);

    return tmp;

}

uint16_t NVRAM_compute_crc (m48t59_t *nvram, uint32_t start, uint32_t count)

{

    uint32_t i;

    uint16_t crc = 0xFFFF;

    int odd;

    odd = count & 1;

    count &= ~1;

    for (i = 0; i != count; i++) {

        crc = NVRAM_crc_update(crc, NVRAM_get_word(nvram, start + i));

    }

    if (odd) {

        crc = NVRAM_crc_update(crc, NVRAM_get_byte(nvram, start + i) << 8);

    }

    return crc;

}

#define CMDLINE_ADDR 0x017ff000

int PPC_NVRAM_set_params (m48t59_t *nvram, uint16_t NVRAM_size,

                          const unsigned char *arch,

                          uint32_t RAM_size, int boot_device,

                          uint32_t kernel_image, uint32_t kernel_size,

                          const char *cmdline,

                          uint32_t initrd_image, uint32_t initrd_size,

                          uint32_t NVRAM_image,

                          int width, int height, int depth)

{

    uint16_t crc;

    /* Set parameters for Open Hack'Ware BIOS */

    NVRAM_set_string(nvram, 0x00, "QEMU_BIOS", 16);

    NVRAM_set_lword(nvram,  0x10, 0x00000002); /* structure v2 */

    NVRAM_set_word(nvram,   0x14, NVRAM_size);

    NVRAM_set_string(nvram, 0x20, arch, 16);

    NVRAM_set_lword(nvram,  0x30, RAM_size);

    NVRAM_set_byte(nvram,   0x34, boot_device);

    NVRAM_set_lword(nvram,  0x38, kernel_image);

    NVRAM_set_lword(nvram,  0x3C, kernel_size);

    if (cmdline) {

        /* XXX: put the cmdline in NVRAM too ? */

        strcpy(phys_ram_base + CMDLINE_ADDR, cmdline);

        NVRAM_set_lword(nvram,  0x40, CMDLINE_ADDR);

        NVRAM_set_lword(nvram,  0x44, strlen(cmdline));

    } else {

        NVRAM_set_lword(nvram,  0x40, 0);

        NVRAM_set_lword(nvram,  0x44, 0);

    }

    NVRAM_set_lword(nvram,  0x48, initrd_image);

    NVRAM_set_lword(nvram,  0x4C, initrd_size);

    NVRAM_set_lword(nvram,  0x50, NVRAM_image);

    NVRAM_set_word(nvram,   0x54, width);

    NVRAM_set_word(nvram,   0x56, height);

    NVRAM_set_word(nvram,   0x58, depth);

    crc = NVRAM_compute_crc(nvram, 0x00, 0xF8);

    NVRAM_set_word(nvram,  0xFC, crc);

    return 0;

}