summaryrefslogtreecommitdiff
path: root/target/arm/gdbstub.c
blob: 1239abd984204e3920032db7f1d7c08db502e04e (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
/*
 * ARM 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"

typedef struct RegisterSysregXmlParam {
    CPUState *cs;
    GString *s;
} RegisterSysregXmlParam;

/* Old gdb always expect FPA registers.  Newer (xml-aware) gdb only expect
   whatever the target description contains.  Due to a historical mishap
   the FPA registers appear in between core integer regs and the CPSR.
   We hack round this by giving the FPA regs zero size when talking to a
   newer gdb.  */

int arm_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n)
{
    ARMCPU *cpu = ARM_CPU(cs);
    CPUARMState *env = &cpu->env;

    if (n < 16) {
        /* Core integer register.  */
        return gdb_get_reg32(mem_buf, env->regs[n]);
    }
    if (n < 24) {
        /* FPA registers.  */
        if (gdb_has_xml) {
            return 0;
        }
        memset(mem_buf, 0, 12);
        return 12;
    }
    switch (n) {
    case 24:
        /* FPA status register.  */
        if (gdb_has_xml) {
            return 0;
        }
        return gdb_get_reg32(mem_buf, 0);
    case 25:
        /* CPSR */
        return gdb_get_reg32(mem_buf, cpsr_read(env));
    }
    /* Unknown register.  */
    return 0;
}

int arm_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
{
    ARMCPU *cpu = ARM_CPU(cs);
    CPUARMState *env = &cpu->env;
    uint32_t tmp;

    tmp = ldl_p(mem_buf);

    /* Mask out low bit of PC to workaround gdb bugs.  This will probably
       cause problems if we ever implement the Jazelle DBX extensions.  */
    if (n == 15) {
        tmp &= ~1;
    }

    if (n < 16) {
        /* Core integer register.  */
        env->regs[n] = tmp;
        return 4;
    }
    if (n < 24) { /* 16-23 */
        /* FPA registers (ignored).  */
        if (gdb_has_xml) {
            return 0;
        }
        return 12;
    }
    switch (n) {
    case 24:
        /* FPA status register (ignored).  */
        if (gdb_has_xml) {
            return 0;
        }
        return 4;
    case 25:
        /* CPSR */
        cpsr_write(env, tmp, 0xffffffff, CPSRWriteByGDBStub);
        return 4;
    }
    /* Unknown register.  */
    return 0;
}

static void arm_gen_one_xml_reg_tag(GString *s, DynamicGDBXMLInfo *dyn_xml,
                                    ARMCPRegInfo *ri, uint32_t ri_key,
                                    int bitsize)
{
    g_string_append_printf(s, "<reg name=\"%s\"", ri->name);
    g_string_append_printf(s, " bitsize=\"%d\"", bitsize);
    g_string_append_printf(s, " group=\"cp_regs\"/>");
    dyn_xml->num_cpregs++;
    dyn_xml->cpregs_keys[dyn_xml->num_cpregs - 1] = ri_key;
}

static void arm_register_sysreg_for_xml(gpointer key, gpointer value,
                                        gpointer p)
{
    uint32_t ri_key = *(uint32_t *)key;
    ARMCPRegInfo *ri = value;
    RegisterSysregXmlParam *param = (RegisterSysregXmlParam *)p;
    GString *s = param->s;
    ARMCPU *cpu = ARM_CPU(param->cs);
    CPUARMState *env = &cpu->env;
    DynamicGDBXMLInfo *dyn_xml = &cpu->dyn_xml;

    if (!(ri->type & (ARM_CP_NO_RAW | ARM_CP_NO_GDB))) {
        if (arm_feature(env, ARM_FEATURE_AARCH64)) {
            if (ri->state == ARM_CP_STATE_AA64) {
                arm_gen_one_xml_reg_tag(s , dyn_xml, ri, ri_key, 64);
            }
        } else {
            if (ri->state == ARM_CP_STATE_AA32) {
                if (!arm_feature(env, ARM_FEATURE_EL3) &&
                    (ri->secure & ARM_CP_SECSTATE_S)) {
                    return;
                }
                if (ri->type & ARM_CP_64BIT) {
                    arm_gen_one_xml_reg_tag(s , dyn_xml, ri, ri_key, 64);
                } else {
                    arm_gen_one_xml_reg_tag(s , dyn_xml, ri, ri_key, 32);
                }
            }
        }
    }
}

int arm_gen_dynamic_xml(CPUState *cs)
{
    ARMCPU *cpu = ARM_CPU(cs);
    GString *s = g_string_new(NULL);
    RegisterSysregXmlParam param = {cs, s};

    cpu->dyn_xml.num_cpregs = 0;
    cpu->dyn_xml.cpregs_keys = g_new(uint32_t, g_hash_table_size(cpu->cp_regs));
    g_string_printf(s, "<?xml version=\"1.0\"?>");
    g_string_append_printf(s, "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">");
    g_string_append_printf(s, "<feature name=\"org.qemu.gdb.arm.sys.regs\">");
    g_hash_table_foreach(cpu->cp_regs, arm_register_sysreg_for_xml, &param);
    g_string_append_printf(s, "</feature>");
    cpu->dyn_xml.desc = g_string_free(s, false);
    return cpu->dyn_xml.num_cpregs;
}

const char *arm_gdb_get_dynamic_xml(CPUState *cs, const char *xmlname)
{
    ARMCPU *cpu = ARM_CPU(cs);

    if (strcmp(xmlname, "system-registers.xml") == 0) {
        return cpu->dyn_xml.desc;
    }
    return NULL;
}