aboutsummaryrefslogtreecommitdiff
path: root/target/xtensa/gdbstub.c
blob: 54727881f38cf4902295f89816622c098ffe6c30 (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
/*
 * Xtensa gdb server stub
 *
 * Copyright (c) 2003-2005 Fabrice Bellard
 * Copyright (c) 2013 SUSE LINUX Products GmbH
 *
 * 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
 * Lesser 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, see <http://www.gnu.org/licenses/>.
 */
#include "qemu/osdep.h"
#include "cpu.h"
#include "exec/gdbstub.h"
#include "qemu/log.h"

enum {
  xtRegisterTypeArRegfile = 1,  /* Register File ar0..arXX.  */
  xtRegisterTypeSpecialReg,     /* CPU states, such as PS, Booleans, (rsr).  */
  xtRegisterTypeUserReg,        /* User defined registers (rur).  */
  xtRegisterTypeTieRegfile,     /* User define register files.  */
  xtRegisterTypeTieState,       /* TIE States (mapped on user regs).  */
  xtRegisterTypeMapped,         /* Mapped on Special Registers.  */
  xtRegisterTypeUnmapped,       /* Special case of masked registers.  */
  xtRegisterTypeWindow,         /* Live window registers (a0..a15).  */
  xtRegisterTypeVirtual,        /* PC, FP.  */
  xtRegisterTypeUnknown
};

#define XTENSA_REGISTER_FLAGS_PRIVILEGED        0x0001
#define XTENSA_REGISTER_FLAGS_READABLE          0x0002
#define XTENSA_REGISTER_FLAGS_WRITABLE          0x0004
#define XTENSA_REGISTER_FLAGS_VOLATILE          0x0008

void xtensa_count_regs(const XtensaConfig *config,
                       unsigned *n_regs, unsigned *n_core_regs)
{
    unsigned i;
    bool count_core_regs = true;

    for (i = 0; config->gdb_regmap.reg[i].targno >= 0; ++i) {
        if (config->gdb_regmap.reg[i].type != xtRegisterTypeTieState &&
            config->gdb_regmap.reg[i].type != xtRegisterTypeMapped &&
            config->gdb_regmap.reg[i].type != xtRegisterTypeUnmapped) {
            ++*n_regs;
            if (count_core_regs) {
                if ((config->gdb_regmap.reg[i].flags &
                     XTENSA_REGISTER_FLAGS_PRIVILEGED) == 0) {
                    ++*n_core_regs;
                } else {
                    count_core_regs = false;
                }
            }
        }
    }
}

int xtensa_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n)
{
    XtensaCPU *cpu = XTENSA_CPU(cs);
    CPUXtensaState *env = &cpu->env;
    const XtensaGdbReg *reg = env->config->gdb_regmap.reg + n;
#ifdef CONFIG_USER_ONLY
    int num_regs = env->config->gdb_regmap.num_core_regs;
#else
    int num_regs = env->config->gdb_regmap.num_regs;
#endif
    unsigned i;

    if (n < 0 || n >= num_regs) {
        return 0;
    }

    switch (reg->type) {
    case xtRegisterTypeVirtual: /*pc*/
        return gdb_get_reg32(mem_buf, env->pc);

    case xtRegisterTypeArRegfile: /*ar*/
        xtensa_sync_phys_from_window(env);
        return gdb_get_reg32(mem_buf, env->phys_regs[(reg->targno & 0xff)
                                                     % env->config->nareg]);

    case xtRegisterTypeSpecialReg: /*SR*/
        return gdb_get_reg32(mem_buf, env->sregs[reg->targno & 0xff]);

    case xtRegisterTypeUserReg: /*UR*/
        return gdb_get_reg32(mem_buf, env->uregs[reg->targno & 0xff]);

    case xtRegisterTypeTieRegfile: /*f*/
        i = reg->targno & 0x0f;
        switch (reg->size) {
        case 4:
            return gdb_get_reg32(mem_buf,
                                 float32_val(env->fregs[i].f32[FP_F32_LOW]));
        case 8:
            return gdb_get_reg64(mem_buf, float64_val(env->fregs[i].f64));
        default:
            qemu_log_mask(LOG_UNIMP, "%s from reg %d of unsupported size %d\n",
                          __func__, n, reg->size);
            memset(mem_buf, 0, reg->size);
            return reg->size;
        }

    case xtRegisterTypeWindow: /*a*/
        return gdb_get_reg32(mem_buf, env->regs[reg->targno & 0x0f]);

    default:
        qemu_log_mask(LOG_UNIMP, "%s from reg %d of unsupported type %d\n",
                      __func__, n, reg->type);
        memset(mem_buf, 0, reg->size);
        return reg->size;
    }
}

int xtensa_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
{
    XtensaCPU *cpu = XTENSA_CPU(cs);
    CPUXtensaState *env = &cpu->env;
    uint32_t tmp;
    const XtensaGdbReg *reg = env->config->gdb_regmap.reg + n;
#ifdef CONFIG_USER_ONLY
    int num_regs = env->config->gdb_regmap.num_core_regs;
#else
    int num_regs = env->config->gdb_regmap.num_regs;
#endif

    if (n < 0 || n >= num_regs) {
        return 0;
    }

    tmp = ldl_p(mem_buf);

    switch (reg->type) {
    case xtRegisterTypeVirtual: /*pc*/
        env->pc = tmp;
        break;

    case xtRegisterTypeArRegfile: /*ar*/
        env->phys_regs[(reg->targno & 0xff) % env->config->nareg] = tmp;
        xtensa_sync_window_from_phys(env);
        break;

    case xtRegisterTypeSpecialReg: /*SR*/
        env->sregs[reg->targno & 0xff] = tmp;
        break;

    case xtRegisterTypeUserReg: /*UR*/
        env->uregs[reg->targno & 0xff] = tmp;
        break;

    case xtRegisterTypeTieRegfile: /*f*/
        switch (reg->size) {
        case 4:
            env->fregs[reg->targno & 0x0f].f32[FP_F32_LOW] = make_float32(tmp);
            return 4;
        case 8:
            env->fregs[reg->targno & 0x0f].f64 = make_float64(tmp);
            return 8;
        default:
            qemu_log_mask(LOG_UNIMP, "%s to reg %d of unsupported size %d\n",
                          __func__, n, reg->size);
            return reg->size;
        }

    case xtRegisterTypeWindow: /*a*/
        env->regs[reg->targno & 0x0f] = tmp;
        break;

    default:
        qemu_log_mask(LOG_UNIMP, "%s to reg %d of unsupported type %d\n",
                      __func__, n, reg->type);
        return reg->size;
    }

    return 4;
}