0.3.4/src/yamon.c

/*
 *  Copyright (C) 2005  Anders Gavare.  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions are met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright  
 *     notice, this list of conditions and the following disclaimer in the 
 *     documentation and/or other materials provided with the distribution.
 *  3. The name of the author may not be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 *  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 *  ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE   
 *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 *  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 *  OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 *  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 *  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 *  OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 *  SUCH DAMAGE.
 *
 *
 *  $Id: yamon.c,v 1.3 2005/06/21 17:42:08 debug Exp $
 *
 *  YAMON emulation.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>

#include "console.h"
#include "cpu.h"
#include "cpu_mips.h"
#include "machine.h"
#include "memory.h"
#include "misc.h"


/*
 *  mem_readchar():
 *  
 *  Reads a byte from emulated RAM, using a MIPS register as a base address.
 *  (Helper function.)
 */
static unsigned char mem_readchar(struct cpu *cpu, int regbase, int offset)
{
        unsigned char ch;
        cpu->memory_rw(cpu, cpu->mem, cpu->cd.mips.gpr[regbase] + offset,
            &ch, sizeof(ch), MEM_READ, CACHE_DATA | NO_EXCEPTIONS);
        return ch;
}


/*
 *  yamon_emul():
 *
 *  YAMON emulation (for evbmips).
 */
int yamon_emul(struct cpu *cpu)
{
        int ofs = cpu->pc & 0xfff;
        int n;

        switch (ofs) {
        case 0x804:     /*  "print count": string at a1, count at a2  */
                n = 0;
                while (n < cpu->cd.mips.gpr[MIPS_GPR_A2]) {
                        char ch = mem_readchar(cpu, MIPS_GPR_A1, n);
                        console_putchar(cpu->machine->main_console_handle,
                            ch);
                        n++;
                }
                break;
        case 0x820:     /*  "exit"  */
                debug("[ yamon_emul(): exit ]\n");
                cpu->running = 0;
                break;
        case 0x854:     /*  "syscon"  */
                fatal("[ yamon_emul(): syscon: TODO ]\n");
                /*  TODO. For now, return some kind of "failure":  */
                cpu->cd.mips.gpr[MIPS_GPR_V0] = 1;
                break;
        default:cpu_register_dump(cpu->machine, cpu, 1, 0);
                printf("\n");
                fatal("[ yamon_emul(): unimplemented ofs 0x%x ]\n", ofs);
                cpu->running = 0;
                cpu->dead = 1;
        }

        return 1;
}

1	/*
2	* Copyright (C) 2005 Anders Gavare. All rights reserved.
3	*
4	* Redistribution and use in source and binary forms, with or without
5	* modification, are permitted provided that the following conditions are met:
6	*
7	* 1. Redistributions of source code must retain the above copyright
8	* notice, this list of conditions and the following disclaimer.
9	* 2. Redistributions in binary form must reproduce the above copyright
10	* notice, this list of conditions and the following disclaimer in the
11	* documentation and/or other materials provided with the distribution.
12	* 3. The name of the author may not be used to endorse or promote products
13	* derived from this software without specific prior written permission.
14	*
15	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18	* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25	* SUCH DAMAGE.
26	*
27	*
28	* $Id: yamon.c,v 1.3 2005/06/21 17:42:08 debug Exp $
29	*
30	* YAMON emulation.
31	*/
32
33	#include <stdio.h>
34	#include <stdlib.h>
35	#include <string.h>
36	#include <sys/types.h>
37
38	#include "console.h"
39	#include "cpu.h"
40	#include "cpu_mips.h"
41	#include "machine.h"
42	#include "memory.h"
43	#include "misc.h"
44
45
46	/*
47	* mem_readchar():
48	*
49	* Reads a byte from emulated RAM, using a MIPS register as a base address.
50	* (Helper function.)
51	*/
52	static unsigned char mem_readchar(struct cpu *cpu, int regbase, int offset)
53	{
54	unsigned char ch;
55	cpu->memory_rw(cpu, cpu->mem, cpu->cd.mips.gpr[regbase] + offset,
56	&ch, sizeof(ch), MEM_READ, CACHE_DATA \| NO_EXCEPTIONS);
57	return ch;
58	}
59
60
61	/*
62	* yamon_emul():
63	*
64	* YAMON emulation (for evbmips).
65	*/
66	int yamon_emul(struct cpu *cpu)
67	{
68	int ofs = cpu->pc & 0xfff;
69	int n;
70
71	switch (ofs) {
72	case 0x804: /* "print count": string at a1, count at a2 */
73	n = 0;
74	while (n < cpu->cd.mips.gpr[MIPS_GPR_A2]) {
75	char ch = mem_readchar(cpu, MIPS_GPR_A1, n);
76	console_putchar(cpu->machine->main_console_handle,
77	ch);
78	n++;
79	}
80	break;
81	case 0x820: /* "exit" */
82	debug("[ yamon_emul(): exit ]\n");
83	cpu->running = 0;
84	break;
85	case 0x854: /* "syscon" */
86	fatal("[ yamon_emul(): syscon: TODO ]\n");
87	/* TODO. For now, return some kind of "failure": */
88	cpu->cd.mips.gpr[MIPS_GPR_V0] = 1;
89	break;
90	default:cpu_register_dump(cpu->machine, cpu, 1, 0);
91	printf("\n");
92	fatal("[ yamon_emul(): unimplemented ofs 0x%x ]\n", ofs);
93	cpu->running = 0;
94	cpu->dead = 1;
95	}
96
97	return 1;
98	}
99