aboutsummaryrefslogtreecommitdiffstats
path: root/target-m68k/helper.c
blob: bdbc1de396bdfb92c010c68e9b52c5e89b3fb390 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
/*
 *  m68k op helpers
 * 
 *  Copyright (c) 2006-2007 CodeSourcery
 *  Written by Paul Brook
 *
 * 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
 * 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 <stdio.h>
#include <string.h>

#include "config.h"
#include "cpu.h"
#include "exec-all.h"

enum m68k_cpuid {
    M68K_CPUID_M5206,
    M68K_CPUID_CFV4E,
    M68K_CPUID_ANY,
};

struct m68k_def_t {
    const char * name;
    enum m68k_cpuid id;
};

static m68k_def_t m68k_cpu_defs[] = {
    {"m5206", M68K_CPUID_M5206}, 
    {"cfv4e", M68K_CPUID_CFV4E},
    {"any", M68K_CPUID_ANY},
    {NULL, 0}, 
};

static void m68k_set_feature(CPUM68KState *env, int feature)
{
    env->features |= (1u << feature);
}

int cpu_m68k_set_model(CPUM68KState *env, const char * name)
{
    m68k_def_t *def;

    for (def = m68k_cpu_defs; def->name; def++) {
        if (strcmp(def->name, name) == 0)
            break;
    }
    if (!def->name)
        return 1;

    switch (def->id) {
    case M68K_CPUID_M5206:
        m68k_set_feature(env, M68K_FEATURE_CF_ISA_A);
        break;
    case M68K_CPUID_CFV4E:
        m68k_set_feature(env, M68K_FEATURE_CF_ISA_A);
        m68k_set_feature(env, M68K_FEATURE_CF_ISA_B);
        m68k_set_feature(env, M68K_FEATURE_CF_ISA_C);
        m68k_set_feature(env, M68K_FEATURE_CF_FPU);
        m68k_set_feature(env, M68K_FEATURE_CF_EMAC);
        break;
    case M68K_CPUID_ANY:
        m68k_set_feature(env, M68K_FEATURE_CF_ISA_A);
        m68k_set_feature(env, M68K_FEATURE_CF_ISA_B);
        m68k_set_feature(env, M68K_FEATURE_CF_ISA_C);
        m68k_set_feature(env, M68K_FEATURE_CF_FPU);
        /* MAC and EMAC are mututally exclusive, so pick EMAC.
           It's mostly backwards compatible.  */
        m68k_set_feature(env, M68K_FEATURE_CF_EMAC);
        m68k_set_feature(env, M68K_FEATURE_EXT_FULL);
        break;
    }

    register_m68k_insns(env);

    return 0;
}

void cpu_m68k_flush_flags(CPUM68KState *env, int cc_op)
{
    int flags;
    uint32_t src;
    uint32_t dest;
    uint32_t tmp;

#define HIGHBIT 0x80000000u

#define SET_NZ(x) do { \
    if ((x) == 0) \
        flags |= CCF_Z; \
    else if ((int32_t)(x) < 0) \
        flags |= CCF_N; \
    } while (0)

#define SET_FLAGS_SUB(type, utype) do { \
    SET_NZ((type)dest); \
    tmp = dest + src; \
    if ((utype) tmp < (utype) src) \
        flags |= CCF_C; \
    if ((1u << (sizeof(type) * 8 - 1)) & (tmp ^ dest) & (tmp ^ src)) \
        flags |= CCF_V; \
    } while (0)

    flags = 0;
    src = env->cc_src;
    dest = env->cc_dest;
    switch (cc_op) {
    case CC_OP_FLAGS:
        flags = dest;
        break;
    case CC_OP_LOGIC:
        SET_NZ(dest);
        break;
    case CC_OP_ADD:
        SET_NZ(dest);
        if (dest < src)
            flags |= CCF_C;
        tmp = dest - src;
        if (HIGHBIT & (src ^ dest) & ~(tmp ^ src))
            flags |= CCF_V;
        break;
    case CC_OP_SUB:
        SET_FLAGS_SUB(int32_t, uint32_t);
        break;
    case CC_OP_CMPB:
        SET_FLAGS_SUB(int8_t, uint8_t);
        break;
    case CC_OP_CMPW:
        SET_FLAGS_SUB(int16_t, uint16_t);
        break;
    case CC_OP_ADDX:
        SET_NZ(dest);
        if (dest <= src)
            flags |= CCF_C;
        tmp = dest - src - 1;
        if (HIGHBIT & (src ^ dest) & ~(tmp ^ src))
            flags |= CCF_V;
        break;
    case CC_OP_SUBX:
        SET_NZ(dest);
        tmp = dest + src + 1;
        if (tmp <= src)
            flags |= CCF_C;
        if (HIGHBIT & (tmp ^ dest) & (tmp ^ src))
            flags |= CCF_V;
        break;
    case CC_OP_SHL:
        if (src >= 32) {
            SET_NZ(0);
        } else {
            tmp = dest << src;
            SET_NZ(tmp);
        }
        if (src && src <= 32 && (dest & (1 << (32 - src))))
            flags |= CCF_C;
        break;
    case CC_OP_SHR:
        if (src >= 32) {
            SET_NZ(0);
        } else {
            tmp = dest >> src;
            SET_NZ(tmp);
        }
        if (src && src <= 32 && ((dest >> (src - 1)) & 1))
            flags |= CCF_C;
        break;
    case CC_OP_SAR:
        if (src >= 32) {
            SET_NZ(-1);
        } else {
            tmp = (int32_t)dest >> src;
            SET_NZ(tmp);
        }
        if (src && src <= 32 && (((int32_t)dest >> (src - 1)) & 1))
            flags |= CCF_C;
        break;
    default:
        cpu_abort(env, "Bad CC_OP %d", cc_op);
    }
    env->cc_op = CC_OP_FLAGS;
    env->cc_dest = flags;
}

float64 helper_sub_cmpf64(CPUM68KState *env, float64 src0, float64 src1)
{
    /* ??? This may incorrectly raise exceptions.  */
    /* ??? Should flush denormals to zero.  */
    float64 res;
    res = float64_sub(src0, src1, &env->fp_status);
    if (float64_is_nan(res)) {
        /* +/-inf compares equal against itself, but sub returns nan.  */
        if (!float64_is_nan(src0)
            && !float64_is_nan(src1)) {
            res = 0;
            if (float64_lt_quiet(src0, res, &env->fp_status))
                res = float64_chs(res);
        }
    }
    return res;
}

void helper_movec(CPUM68KState *env, int reg, uint32_t val)
{
    switch (reg) {
    case 0x02: /* CACR */
        /* Ignored.  */
        break;
    case 0x801: /* VBR */
        env->vbr = val;
        break;
    /* TODO: Implement control registers.  */
    default:
        cpu_abort(env, "Unimplemented control register write 0x%x = 0x%x\n",
                  reg, val);
    }
}

void m68k_set_macsr(CPUM68KState *env, uint32_t val)
{
    uint32_t acc;
    int8_t exthigh;
    uint8_t extlow;
    uint64_t regval;
    int i;
    if ((env->macsr ^ val) & (MACSR_FI | MACSR_SU)) {
        for (i = 0; i < 4; i++) {
            regval = env->macc[i];
            exthigh = regval >> 40;
            if (env->macsr & MACSR_FI) {
                acc = regval >> 8;
                extlow = regval;
            } else {
                acc = regval;
                extlow = regval >> 32;
            }
            if (env->macsr & MACSR_FI) {
                regval = (((uint64_t)acc) << 8) | extlow;
                regval |= ((int64_t)exthigh) << 40;
            } else if (env->macsr & MACSR_SU) {
                regval = acc | (((int64_t)extlow) << 32);
                regval |= ((int64_t)exthigh) << 40;
            } else {
                regval = acc | (((uint64_t)extlow) << 32);
                regval |= ((uint64_t)(uint8_t)exthigh) << 40;
            }
            env->macc[i] = regval;
        }
    }
    env->macsr = val;
}

/* MMU */

/* TODO: This will need fixing once the MMU is implemented.  */
target_phys_addr_t cpu_get_phys_page_debug(CPUState *env, target_ulong addr)
{
    return addr;
}

#if defined(CONFIG_USER_ONLY) 

int cpu_m68k_handle_mmu_fault (CPUState *env, target_ulong address, int rw,
                               int is_user, int is_softmmu)
{
    env->exception_index = EXCP_ACCESS;
    env->mmu.ar = address;
    return 1;
}

#else

int cpu_m68k_handle_mmu_fault (CPUState *env, target_ulong address, int rw,
                               int is_user, int is_softmmu)
{
    int prot;

    address &= TARGET_PAGE_MASK;
    prot = PAGE_READ | PAGE_WRITE;
    return tlb_set_page(env, address, address, prot, is_user, is_softmmu);
}

/* Notify CPU of a pending interrupt.  Prioritization and vectoring should
   be handled by the interrupt controller.  Real hardware only requests
   the vector when the interrupt is acknowledged by the CPU.  For
   simplicitly we calculate it when the interrupt is signalled.  */
void m68k_set_irq_level(CPUM68KState *env, int level, uint8_t vector)
{
    env->pending_level = level;
    env->pending_vector = vector;
    if (level)
        cpu_interrupt(env, CPU_INTERRUPT_HARD);
    else
        cpu_reset_interrupt(env, CPU_INTERRUPT_HARD);
}

#endif