/*
 * This file is part of SIS.
 * 
 * SIS, SPARC instruction simulator V1.6 Copyright (C) 1995 Jiri Gaisler,
 * European Space Agency
 * 
 * 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 <signal.h>
#include <string.h>
#include <stdio.h>
#include <sys/fcntl.h>
#include "sis.h"
#include "bfd.h"
#include <dis-asm.h>

#include "remote-sim.h"

#ifndef fprintf
extern          fprintf();
#endif

#define	VAL(x)	strtol(x,(char *)NULL,0)

extern char   **buildargv(char *input);

extern struct disassemble_info dinfo;
extern struct pstate sregs;
extern struct estate ebase;

extern int      ctrl_c;
extern int      nfp;
extern int      ift;
extern int      rom8;
extern int      wrp;
extern int      sis_verbose;
extern char    *sis_version;
extern struct estate ebase;
extern struct evcell evbuf[];
extern struct irqcell irqarr[];
extern int      irqpend, ext_irl;
extern int      sparclite;
extern int      termsave;
extern char     uart_dev1[], uart_dev2[];

int             sis_gdb_break = 1;

host_callback *sim_callback;

run_sim(sregs, go, icount, dis)
    struct pstate  *sregs;
    int             go;
    unsigned int    icount;
    int             dis;
{
    int             mexc, ws;

    if (sis_verbose)
	(*sim_callback->printf_filtered) (sim_callback, "resuming at %x\n",
					  sregs->pc);
   init_stdio();
   sregs->starttime = time(NULL);
    while ((!sregs->err_mode & (go || (icount > 0))) &&
	   ((sregs->bptnum == 0) || !(sregs->bphit = check_bpt(sregs)))) {

	sregs->fhold = 0;
	sregs->hold = 0;
	sregs->icnt = 0;

	check_interrupts(sregs);
	if (sregs->trap) {
	    sregs->err_mode = execute_trap(sregs);
	} else {
	    if (sregs->psr & 0x080)
		sregs->asi = 8;
	    else
		sregs->asi = 9;

	    mexc = memory_read(sregs->asi, sregs->pc, &sregs->inst, &sregs->hold);
	    if (sregs->annul) {
		sregs->annul = 0;
		sregs->icnt = 1;
		sregs->pc = sregs->npc;
		sregs->npc = sregs->npc + 4;
	    } else {
		if (mexc) {
		    sregs->trap = I_ACC_EXC;
		} else {
		    if (sregs->histlen) {
			sregs->histbuf[sregs->histind].addr = sregs->pc;
			sregs->histbuf[sregs->histind].time = ebase.simtime;
			sregs->histind++;
			if (sregs->histind >= sregs->histlen)
			    sregs->histind = 0;
		    }
		    if (dis) {
			printf(" %8d ", ebase.simtime);
			dis_mem(sregs->pc, 1, &dinfo);
		    }
		    if ((sis_gdb_break) && (sregs->inst == 0x91d02001)) {
			if (sis_verbose)
			    (*sim_callback->printf_filtered) (sim_callback,
							      "SW BP hit at %x\n", sregs->pc);
			return (BPT_HIT);
		    } else
			dispatch_instruction(sregs);
		}
		icount--;
	    }
	    if (sregs->trap) {
		sregs->err_mode = execute_trap(sregs);
	    }
	}
	advance_time(sregs);
	if (ctrl_c) {
	    go = icount = 0;
	}
    }
    sim_stop();
    sregs->tottime += time(NULL) - sregs->starttime;
    restore_stdio();
    clearerr(stdin);
    if (sregs->err_mode)
	error_mode(sregs->pc);
    if (sregs->err_mode)
	return (ERROR);
    if (sregs->bphit) {
	if (sis_verbose)
	    (*sim_callback->printf_filtered) (sim_callback,
					      "HW BP hit at %x\n", sregs->pc);
	return (BPT_HIT);
    }
    if (ctrl_c) {
	ctrl_c = 0;
	return (CTRL_C);
    }
    return (TIME_OUT);
}

void
sim_set_callbacks (ptr)
     host_callback *ptr;
{
  sim_callback = ptr;
}

void
sim_size (memsize)
     int memsize;
{
}

void
sim_open(args)
     char *args;
{

    int             argc = 0;
    char          **argv;
    int             cont = 1;
    int             stat = 0;
    int             grdl = 0;
    int             freq = 15;

    (*sim_callback->printf_filtered) (sim_callback, "\n SIS - SPARC instruction simulator %s\n", sis_version);
    (*sim_callback->printf_filtered) (sim_callback, " Bug-reports to Jiri Gaisler ESA/ESTEC (jgais@wd.estec.esa.nl)\n");
    argv = buildargv(args);
    if (argv != NULL)
	while (argv[argc])
	    argc++;
    while (stat < argc) {
	if (argv[stat][0] == '-') {
	    if (strcmp(argv[stat], "-v") == 0) {
		sis_verbose = 1;
	    } else
	    if (strcmp(argv[stat], "-nfp") == 0) {
		(*sim_callback->printf_filtered) (sim_callback, "no FPU\n");
		nfp = 1;
	    } else
            if (strcmp(argv[stat], "-ift") == 0) {
                ift = 1;
	    } else
	    if (strcmp(argv[stat], "-sparclite") == 0) {
		(*sim_callback->printf_filtered) (sim_callback, "simulating Sparclite\n");
		sparclite = 1;
	    } else
            if (strcmp(argv[stat], "-wrp") == 0) {
                wrp = 1;
	    } else
            if (strcmp(argv[stat], "-rom8") == 0) {
                rom8 = 1;
	    } else 
	    if (strcmp(argv[stat], "-uart1") == 0) {
		if ((stat + 1) < argc)
		    strcpy(uart_dev1, argv[++stat]);
	    } else
	    if (strcmp(argv[stat], "-uart2") == 0) {
		if ((stat + 1) < argc)
		    strcpy(uart_dev2, argv[++stat]);
	    } else
	    if (strcmp(argv[stat], "-nogdb") == 0) {
		(*sim_callback->printf_filtered) (sim_callback, "disabling GDB trap handling for breakpoints\n");
		sis_gdb_break = 0;
	    } else
	    if (strcmp(argv[stat], "-freq") == 0)
		if ((stat + 1) < argc) {
		    freq = VAL(argv[++stat]);
		    (*sim_callback->printf_filtered) (sim_callback, " ERC32 freq %d Mhz\n", freq);
		}
	} else
	    bfd_load(argv[stat]);
	stat++;
    }
    freeargv(argv);
    sregs.freq = freq;
    termsave = fcntl(0, F_GETFL, 0);
    INIT_DISASSEMBLE_INFO(dinfo, stdout,(fprintf_ftype)fprintf);
    init_signals();
    reset_all();
    ebase.simtime = 0;
    init_sim();
    init_bpt(&sregs);
    reset_stat(&sregs);
}

void
sim_close(int quitting)
{

    exit_sim();
    fcntl(0, F_SETFL, termsave);

};

/* Return non-zero if the caller should handle the load. Zero if
     we have loaded the image. */

int sim_load PARAMS ((char *prog, int from_tty));

int
sim_load(prog, from_tty)
     char *prog;
     int from_tty;
{
    bfd_load(prog);
    return (0);
}

void sim_create_inferior PARAMS ((SIM_ADDR start_address, char **argv, char **env));

void
sim_create_inferior(start_address, argv, env)
     SIM_ADDR start_address;
     char **argv;
     char **env;
{
    ebase.simtime = 0;
    reset_all();
    reset_stat(&sregs);
    sregs.pc = start_address & ~3;
    sregs.npc = sregs.pc + 4;

}

void
sim_store_register(regno, value)
    int             regno;
    unsigned char  *value;
{
    /* FIXME: Review the computation of regval.  */
    int             regval = (value[0] << 24) | (value[1] << 16) | (value[2] << 8) | value[3];
    set_regi(&sregs, regno, regval);
}


void
sim_fetch_register(regno, buf)
    int             regno;
    unsigned char  *buf;
{
    get_regi(&sregs, regno, buf);
}

int
sim_write(mem, buf, length)
    SIM_ADDR             mem;
    unsigned char  *buf;
    int             length;
{
    return (sis_memory_write(mem, buf, length));
}

int sim_read PARAMS ((SIM_ADDR mem, unsigned char *buf, int length));

int
sim_read(mem, buf, length)
     SIM_ADDR mem;
     unsigned char *buf;
     int length;
{
    return (sis_memory_read(mem, buf, length));
}

void
sim_info(int verbose)
{
    show_stat(&sregs);


}

int             simstat = OK;

void
sim_stop_reason(enum sim_stop * reason, int *sigrc)
{

    switch (simstat) {
	case CTRL_C:
	*reason = sim_stopped;
	*sigrc = SIGINT;
	break;
    case OK:
    case TIME_OUT:
    case BPT_HIT:
	*reason = sim_stopped;
#ifdef _WIN32
#define SIGTRAP 5
#endif
	*sigrc = SIGTRAP;
	break;
    case ERROR:
	*sigrc = 0;
	*reason = sim_exited;
    }
    ctrl_c = 0;
    simstat = OK;
}

/* Flush all register windows out to the stack.  Starting after the invalid
   window, flush all windows up to, and including the current window.  This
   allows GDB to do backtraces and look at local variables for frames that
   are still in the register windows.  Note that strictly speaking, this
   behavior is *wrong* for several reasons.  First, it doesn't use the window
   overflow handlers.  It therefore assumes standard frame layouts and window
   handling policies.  Second, it changes system state behind the back of the
   target program.  I expect this to mainly pose problems when debugging trap
   handlers.
*/

#define PSR_CWP 0x7

static void
flush_windows ()
{
  int invwin;
  int cwp;
  int win;
  int ws;

  /* Keep current window handy */

  cwp = sregs.psr & PSR_CWP;

  /* Calculate the invalid window from the wim. */

  for (invwin = 0; invwin <= PSR_CWP; invwin++)
    if ((sregs.wim >> invwin) & 1)
      break;

  /* Start saving with the window after the invalid window. */

  invwin = (invwin - 1) & PSR_CWP;

  for (win = invwin; ; win = (win - 1) & PSR_CWP)
    {
      uint32 sp;
      int i;

      sp = sregs.r[(win * 16 + 14) & 0x7f];

      for (i = 0; i < 16; i++)
	memory_write (11, sp + 4 * i, &sregs.r[(win * 16 + 16 + i) & 0x7f], 2,
		      &ws);

      if (win == cwp)
	break;
    }
}

void
sim_resume(int step, int siggnal)
{
    simstat = run_sim(&sregs, 1, 0, 0);

    if (sis_gdb_break) flush_windows ();
}

int
sim_trace ()
{
  /* FIXME: unfinished */
  sim_resume (0, 0);
  return 1;
}

void
sim_kill(void)
{
}

void
sim_do_command(cmd)
    char           *cmd;
{
    exec_cmd(&sregs, cmd);
}

#if 0 /* FIXME: These shouldn't exist.  */

int
sim_insert_breakpoint(int addr)
{
    if (sregs.bptnum < BPT_MAX) {
	sregs.bpts[sregs.bptnum] = addr & ~0x3;
	sregs.bptnum++;
	if (sis_verbose)
	    (*sim_callback->printf_filtered) (sim_callback, "inserted HW BP at %x\n", addr);
	return 0;
    } else
	return 1;
}

int
sim_remove_breakpoint(int addr)
{
    int             i = 0;

    while ((i < sregs.bptnum) && (sregs.bpts[i] != addr))
	i++;
    if (addr == sregs.bpts[i]) {
	for (; i < sregs.bptnum - 1; i++)
	    sregs.bpts[i] = sregs.bpts[i + 1];
	sregs.bptnum -= 1;
	if (sis_verbose)
	    (*sim_callback->printf_filtered) (sim_callback, "removed HW BP at %x\n", addr);
	return 0;
    }
    return 1;
}

#endif