1/*
2 * ARM gdb server stub
3 *
4 * Copyright (c) 2003-2005 Fabrice Bellard
5 * Copyright (c) 2013 SUSE LINUX Products GmbH
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
19 */
20#include "qemu/osdep.h"
21#include "cpu.h"
22#include "exec/gdbstub.h"
23
24typedef struct RegisterSysregXmlParam {
25 CPUState *cs;
26 GString *s;
27} RegisterSysregXmlParam;
28
29/* Old gdb always expect FPA registers. Newer (xml-aware) gdb only expect
30 whatever the target description contains. Due to a historical mishap
31 the FPA registers appear in between core integer regs and the CPSR.
32 We hack round this by giving the FPA regs zero size when talking to a
33 newer gdb. */
34
35int arm_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n)
36{
37 ARMCPU *cpu = ARM_CPU(cs);
38 CPUARMState *env = &cpu->env;
39
40 if (n < 16) {
41 /* Core integer register. */
42 return gdb_get_reg32(mem_buf, env->regs[n]);
43 }
44 if (n < 24) {
45 /* FPA registers. */
46 if (gdb_has_xml) {
47 return 0;
48 }
49 memset(mem_buf, 0, 12);
50 return 12;
51 }
52 switch (n) {
53 case 24:
54 /* FPA status register. */
55 if (gdb_has_xml) {
56 return 0;
57 }
58 return gdb_get_reg32(mem_buf, 0);
59 case 25:
60 /* CPSR */
61 return gdb_get_reg32(mem_buf, cpsr_read(env));
62 }
63 /* Unknown register. */
64 return 0;
65}
66
67int arm_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
68{
69 ARMCPU *cpu = ARM_CPU(cs);
70 CPUARMState *env = &cpu->env;
71 uint32_t tmp;
72
73 tmp = ldl_p(mem_buf);
74
75 /* Mask out low bit of PC to workaround gdb bugs. This will probably
76 cause problems if we ever implement the Jazelle DBX extensions. */
77 if (n == 15) {
78 tmp &= ~1;
79 }
80
81 if (n < 16) {
82 /* Core integer register. */
83 env->regs[n] = tmp;
84 return 4;
85 }
86 if (n < 24) { /* 16-23 */
87 /* FPA registers (ignored). */
88 if (gdb_has_xml) {
89 return 0;
90 }
91 return 12;
92 }
93 switch (n) {
94 case 24:
95 /* FPA status register (ignored). */
96 if (gdb_has_xml) {
97 return 0;
98 }
99 return 4;
100 case 25:
101 /* CPSR */
102 cpsr_write(env, tmp, 0xffffffff, CPSRWriteByGDBStub);
103 return 4;
104 }
105 /* Unknown register. */
106 return 0;
107}
108
109static void arm_gen_one_xml_reg_tag(GString *s, DynamicGDBXMLInfo *dyn_xml,
110 ARMCPRegInfo *ri, uint32_t ri_key,
111 int bitsize)
112{
113 g_string_append_printf(s, "<reg name=\"%s\"", ri->name);
114 g_string_append_printf(s, " bitsize=\"%d\"", bitsize);
115 g_string_append_printf(s, " group=\"cp_regs\"/>");
116 dyn_xml->num_cpregs++;
117 dyn_xml->cpregs_keys[dyn_xml->num_cpregs - 1] = ri_key;
118}
119
120static void arm_register_sysreg_for_xml(gpointer key, gpointer value,
121 gpointer p)
122{
123 uint32_t ri_key = *(uint32_t *)key;
124 ARMCPRegInfo *ri = value;
125 RegisterSysregXmlParam *param = (RegisterSysregXmlParam *)p;
126 GString *s = param->s;
127 ARMCPU *cpu = ARM_CPU(param->cs);
128 CPUARMState *env = &cpu->env;
129 DynamicGDBXMLInfo *dyn_xml = &cpu->dyn_xml;
130
131 if (!(ri->type & (ARM_CP_NO_RAW | ARM_CP_NO_GDB))) {
132 if (arm_feature(env, ARM_FEATURE_AARCH64)) {
133 if (ri->state == ARM_CP_STATE_AA64) {
134 arm_gen_one_xml_reg_tag(s , dyn_xml, ri, ri_key, 64);
135 }
136 } else {
137 if (ri->state == ARM_CP_STATE_AA32) {
138 if (!arm_feature(env, ARM_FEATURE_EL3) &&
139 (ri->secure & ARM_CP_SECSTATE_S)) {
140 return;
141 }
142 if (ri->type & ARM_CP_64BIT) {
143 arm_gen_one_xml_reg_tag(s , dyn_xml, ri, ri_key, 64);
144 } else {
145 arm_gen_one_xml_reg_tag(s , dyn_xml, ri, ri_key, 32);
146 }
147 }
148 }
149 }
150}
151
152int arm_gen_dynamic_xml(CPUState *cs)
153{
154 ARMCPU *cpu = ARM_CPU(cs);
155 GString *s = g_string_new(NULL);
156 RegisterSysregXmlParam param = {cs, s};
157
158 cpu->dyn_xml.num_cpregs = 0;
159 cpu->dyn_xml.cpregs_keys = g_new(uint32_t, g_hash_table_size(cpu->cp_regs));
160 g_string_printf(s, "<?xml version=\"1.0\"?>");
161 g_string_append_printf(s, "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">");
162 g_string_append_printf(s, "<feature name=\"org.qemu.gdb.arm.sys.regs\">");
163 g_hash_table_foreach(cpu->cp_regs, arm_register_sysreg_for_xml, &param);
164 g_string_append_printf(s, "</feature>");
165 cpu->dyn_xml.desc = g_string_free(s, false);
166 return cpu->dyn_xml.num_cpregs;
167}
168
169const char *arm_gdb_get_dynamic_xml(CPUState *cs, const char *xmlname)
170{
171 ARMCPU *cpu = ARM_CPU(cs);
172
173 if (strcmp(xmlname, "system-registers.xml") == 0) {
174 return cpu->dyn_xml.desc;
175 }
176 return NULL;
177}
178