Archipelago » qemu

VL_OBJS+= arm-semi.o

/*

 *  Arm "Angel" semihosting syscalls

 * 

 *  Copyright (c) 2005, 2007 CodeSourcery.

 *  Written by Paul Brook.

 *

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

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; either version 2 of the License, or

 *  (at your option) any later version.

 *

 *  This program 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 General Public License for more details.

 *

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

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

 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

 */

#include <sys/types.h>

#include <sys/stat.h>

#include <fcntl.h>

#include <unistd.h>

#include <stdlib.h>

#include <stdio.h>

#include <time.h>

#include "cpu.h"

#ifdef CONFIG_USER_ONLY

#include "qemu.h"

#define ARM_ANGEL_HEAP_SIZE (128 * 1024 * 1024)

#else

#include "vl.h"

#endif

#define SYS_OPEN        0x01

#define SYS_CLOSE       0x02

#define SYS_WRITEC      0x03

#define SYS_WRITE0      0x04

#define SYS_WRITE       0x05

#define SYS_READ        0x06

#define SYS_READC       0x07

#define SYS_ISTTY       0x09

#define SYS_SEEK        0x0a

#define SYS_FLEN        0x0c

#define SYS_TMPNAM      0x0d

#define SYS_REMOVE      0x0e

#define SYS_RENAME      0x0f

#define SYS_CLOCK       0x10

#define SYS_TIME        0x11

#define SYS_SYSTEM      0x12

#define SYS_ERRNO       0x13

#define SYS_GET_CMDLINE 0x15

#define SYS_HEAPINFO    0x16

#define SYS_EXIT        0x18

#ifndef O_BINARY

#define O_BINARY 0

#endif

int open_modeflags[12] = {

    O_RDONLY,

    O_RDONLY | O_BINARY,

    O_RDWR,

    O_RDWR | O_BINARY,

    O_WRONLY | O_CREAT | O_TRUNC,

    O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,

    O_RDWR | O_CREAT | O_TRUNC,

    O_RDWR | O_CREAT | O_TRUNC | O_BINARY,

    O_WRONLY | O_CREAT | O_APPEND,

    O_WRONLY | O_CREAT | O_APPEND | O_BINARY,

    O_RDWR | O_CREAT | O_APPEND,

    O_RDWR | O_CREAT | O_APPEND | O_BINARY

};

#ifdef CONFIG_USER_ONLY

static inline uint32_t set_swi_errno(TaskState *ts, uint32_t code)

{

    if (code == (uint32_t)-1)

        ts->swi_errno = errno;

    return code;

}

#else

static inline uint32_t set_swi_errno(CPUState *env, uint32_t code)

{

    return code;

}

static uint32_t softmmu_tget32(CPUState *env, uint32_t addr)

{

    uint32_t val;

    cpu_memory_rw_debug(env, addr, (uint8_t *)&val, 4, 0);

    return tswap32(val);

}

static uint32_t softmmu_tget8(CPUState *env, uint32_t addr)

{

    uint8_t val;

    cpu_memory_rw_debug(env, addr, &val, 1, 0);

    return val;

}

#define tget32(p) softmmu_tget32(env, p)

#define tget8(p) softmmu_tget8(env, p)

static void *softmmu_lock_user(CPUState *env, uint32_t addr, uint32_t len,

                               int copy)

{

    char *p;

    /* TODO: Make this something that isn't fixed size.  */

    p = malloc(len);

    if (copy)

        cpu_memory_rw_debug(env, addr, p, len, 0);

    return p;

}

#define lock_user(p, len, copy) softmmu_lock_user(env, p, len, copy)

static char *softmmu_lock_user_string(CPUState *env, uint32_t addr)

{

    char *p;

    char *s;

    uint8_t c;

    /* TODO: Make this something that isn't fixed size.  */

    s = p = malloc(1024);

    do {

        cpu_memory_rw_debug(env, addr, &c, 1, 0);

        addr++;

        *(p++) = c;

    } while (c);

    return s;

}

#define lock_user_string(p) softmmu_lock_user_string(env, p)

static void softmmu_unlock_user(CPUState *env, void *p, target_ulong addr,

                                target_ulong len)

{

    if (len)

        cpu_memory_rw_debug(env, addr, p, len, 1);

    free(p);

}

#define unlock_user(s, args, len) softmmu_unlock_user(env, s, args, len)

#endif

#define ARG(n) tget32(args + (n) * 4)

#define SET_ARG(n, val) tput32(args + (n) * 4,val)

uint32_t do_arm_semihosting(CPUState *env)

{

    target_ulong args;

    char * s;

    int nr;

    uint32_t ret;

    uint32_t len;

#ifdef CONFIG_USER_ONLY

    TaskState *ts = env->opaque;

#else

    CPUState *ts = env;

#endif

    nr = env->regs[0];

    args = env->regs[1];

    switch (nr) {

    case SYS_OPEN:

        s = lock_user_string(ARG(0));

        if (ARG(1) >= 12)

          return (uint32_t)-1;

        if (strcmp(s, ":tt") == 0) {

            if (ARG(1) < 4)

                return STDIN_FILENO;

            else

                return STDOUT_FILENO;

        }

        ret = set_swi_errno(ts, open(s, open_modeflags[ARG(1)], 0644));

        unlock_user(s, ARG(0), 0);

        return ret;

    case SYS_CLOSE:

        return set_swi_errno(ts, close(ARG(0)));

    case SYS_WRITEC:

        {

          char c = tget8(args);

          /* Write to debug console.  stderr is near enough.  */

          return write(STDERR_FILENO, &c, 1);

        }

    case SYS_WRITE0:

        s = lock_user_string(args);

        ret = write(STDERR_FILENO, s, strlen(s));

        unlock_user(s, args, 0);

        return ret;

    case SYS_WRITE:

        len = ARG(2);

        s = lock_user(ARG(1), len, 1);

        ret = set_swi_errno(ts, write(ARG(0), s, len));

        unlock_user(s, ARG(1), 0);

        if (ret == (uint32_t)-1)

            return -1;

        return ARG(2) - ret;

    case SYS_READ:

        len = ARG(2);

        s = lock_user(ARG(1), len, 0);

	do

	  ret = set_swi_errno(ts, read(ARG(0), s, len));

	while (ret == -1 && errno == EINTR);

        unlock_user(s, ARG(1), len);

        if (ret == (uint32_t)-1)

            return -1;

        return ARG(2) - ret;

    case SYS_READC:

       /* XXX: Read from debug cosole. Not implemented.  */

        return 0;

    case SYS_ISTTY:

        return isatty(ARG(0));

    case SYS_SEEK:

        ret = set_swi_errno(ts, lseek(ARG(0), ARG(1), SEEK_SET));

	if (ret == (uint32_t)-1)

	  return -1;

	return 0;

    case SYS_FLEN:

        {

            struct stat buf;

            ret = set_swi_errno(ts, fstat(ARG(0), &buf));

            if (ret == (uint32_t)-1)

                return -1;

            return buf.st_size;

        }

    case SYS_TMPNAM:

        /* XXX: Not implemented.  */

        return -1;

    case SYS_REMOVE:

        s = lock_user_string(ARG(0));

        ret =  set_swi_errno(ts, remove(s));

        unlock_user(s, ARG(0), 0);

        return ret;

    case SYS_RENAME:

        {

            char *s2;

            s = lock_user_string(ARG(0));

            s2 = lock_user_string(ARG(2));

            ret = set_swi_errno(ts, rename(s, s2));

            unlock_user(s2, ARG(2), 0);

            unlock_user(s, ARG(0), 0);

            return ret;

        }

    case SYS_CLOCK:

        return clock() / (CLOCKS_PER_SEC / 100);

    case SYS_TIME:

        return set_swi_errno(ts, time(NULL));

    case SYS_SYSTEM:

        s = lock_user_string(ARG(0));

        ret = set_swi_errno(ts, system(s));

        unlock_user(s, ARG(0), 0);

    case SYS_ERRNO:

#ifdef CONFIG_USER_ONLY

        return ts->swi_errno;

#else

        return 0;

#endif

    case SYS_GET_CMDLINE:

#ifdef CONFIG_USER_ONLY

        /* Build a commandline from the original argv.  */

        {

            char **arg = ts->info->host_argv;

            int len = ARG(1);

            /* lock the buffer on the ARM side */

            char *cmdline_buffer = (char*)lock_user(ARG(0), len, 0);

            s = cmdline_buffer;

            while (*arg && len > 2) {

                int n = strlen(*arg);

                if (s != cmdline_buffer) {

                    *(s++) = ' ';

                    len--;

                }

                if (n >= len)

                    n = len - 1;

                memcpy(s, *arg, n);

                s += n;

                len -= n;

                arg++;

            }

            /* Null terminate the string.  */

            *s = 0;

            len = s - cmdline_buffer;

            /* Unlock the buffer on the ARM side.  */

            unlock_user(cmdline_buffer, ARG(0), len);

            /* Adjust the commandline length argument.  */

            SET_ARG(1, len);

            /* Return success if commandline fit into buffer.  */

            return *arg ? -1 : 0;

        }

#else

      return -1;

#endif

    case SYS_HEAPINFO:

        {

            uint32_t *ptr;

            uint32_t limit;

#ifdef CONFIG_USER_ONLY

            /* Some C libraries assume the heap immediately follows .bss, so

               allocate it using sbrk.  */

            if (!ts->heap_limit) {

                long ret;

                ts->heap_base = do_brk(0);

                limit = ts->heap_base + ARM_ANGEL_HEAP_SIZE;

                /* Try a big heap, and reduce the size if that fails.  */

                for (;;) {

                    ret = do_brk(limit);

                    if (ret != -1)

                        break;

                    limit = (ts->heap_base >> 1) + (limit >> 1);

                }

                ts->heap_limit = limit;

            }

            ptr = lock_user(ARG(0), 16, 0);

            ptr[0] = tswap32(ts->heap_base);

            ptr[1] = tswap32(ts->heap_limit);

            ptr[2] = tswap32(ts->stack_base);

            ptr[3] = tswap32(0); /* Stack limit.  */

            unlock_user(ptr, ARG(0), 16);

#else

            limit = ram_size;

            ptr = lock_user(ARG(0), 16, 0);

            /* TODO: Make this use the limit of the loaded application.  */

            ptr[0] = tswap32(limit / 2);

            ptr[1] = tswap32(limit);

            ptr[2] = tswap32(limit); /* Stack base */

            ptr[3] = tswap32(0); /* Stack limit.  */

            unlock_user(ptr, ARG(0), 16);

#endif

            return 0;

        }

    case SYS_EXIT:

        exit(0);

    default:

        fprintf(stderr, "qemu: Unsupported SemiHosting SWI 0x%02x\n", nr);

        cpu_dump_state(env, stderr, fprintf, 0);

        abort();

    }

}

@item -semihosting

Enable "Angel" semihosting interface (ARM target machines only).

Note that this allows guest direct access to the host filesystem,

so should only be used with trusted guest OS.

extern int semihosting_enabled;

        if (semihosting_enabled) {

            /* Check for semihosting interrupt.  */

            if (env->thumb) {

                mask = lduw_code(env->regs[15] - 2) & 0xff;

            } else {

                mask = ldl_code(env->regs[15] - 4) & 0xffffff;

            }

            /* Only intercept calls from privileged modes, to provide some

               semblance of security.  */

            if (((mask == 0x123456 && !env->thumb)

                    || (mask == 0xab && env->thumb))

                  && (env->uncached_cpsr & CPSR_M) != ARM_CPU_MODE_USR) {

                env->regs[0] = do_arm_semihosting(env);

                return;

            }

        }

int semihosting_enabled = 0;

    QEMU_OPTION_semihosting

#if defined(TARGET_ARM)

    { "semihosting", 0, QEMU_OPTION_semihosting },

#endif

            case QEMU_OPTION_semihosting:

                semihosting_enabled = 1;

                break;

extern int semihosting_enabled;