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linux-m68k-low.c
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1 /* GNU/Linux/m68k specific low level interface, for the remote server for GDB.
2 Copyright (C) 1995-2018 Free Software Foundation, Inc.
3
4 This file is part of GDB.
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
18
19 #include "server.h"
20 #include "linux-low.h"
21
22 /* Defined in auto-generated file reg-m68k.c. */
23 void init_registers_m68k (void);
24 extern const struct target_desc *tdesc_m68k;
25
26 #ifdef HAVE_SYS_REG_H
27 #include <sys/reg.h>
28 #endif
29
30 #define m68k_num_regs 29
31 #define m68k_num_gregs 18
32
33 /* This table must line up with REGISTER_NAMES in tm-m68k.h */
34 static int m68k_regmap[] =
35 {
36 #ifdef PT_D0
37 PT_D0 * 4, PT_D1 * 4, PT_D2 * 4, PT_D3 * 4,
38 PT_D4 * 4, PT_D5 * 4, PT_D6 * 4, PT_D7 * 4,
39 PT_A0 * 4, PT_A1 * 4, PT_A2 * 4, PT_A3 * 4,
40 PT_A4 * 4, PT_A5 * 4, PT_A6 * 4, PT_USP * 4,
41 PT_SR * 4, PT_PC * 4,
42 #else
43 14 * 4, 0 * 4, 1 * 4, 2 * 4, 3 * 4, 4 * 4, 5 * 4, 6 * 4,
44 7 * 4, 8 * 4, 9 * 4, 10 * 4, 11 * 4, 12 * 4, 13 * 4, 15 * 4,
45 17 * 4, 18 * 4,
46 #endif
47 #ifdef PT_FP0
48 PT_FP0 * 4, PT_FP1 * 4, PT_FP2 * 4, PT_FP3 * 4,
49 PT_FP4 * 4, PT_FP5 * 4, PT_FP6 * 4, PT_FP7 * 4,
50 PT_FPCR * 4, PT_FPSR * 4, PT_FPIAR * 4
51 #else
52 21 * 4, 24 * 4, 27 * 4, 30 * 4, 33 * 4, 36 * 4,
53 39 * 4, 42 * 4, 45 * 4, 46 * 4, 47 * 4
54 #endif
55 };
56
57 static int
58 m68k_cannot_store_register (int regno)
59 {
60 return (regno >= m68k_num_regs);
61 }
62
63 static int
64 m68k_cannot_fetch_register (int regno)
65 {
66 return (regno >= m68k_num_regs);
67 }
68
69 #ifdef HAVE_PTRACE_GETREGS
70 #include <sys/procfs.h>
71 #include "nat/gdb_ptrace.h"
72
73 static void
74 m68k_fill_gregset (struct regcache *regcache, void *buf)
75 {
76 int i;
77
78 for (i = 0; i < m68k_num_gregs; i++)
79 collect_register (regcache, i, (char *) buf + m68k_regmap[i]);
80 }
81
82 static void
83 m68k_store_gregset (struct regcache *regcache, const void *buf)
84 {
85 int i;
86
87 for (i = 0; i < m68k_num_gregs; i++)
88 supply_register (regcache, i, (const char *) buf + m68k_regmap[i]);
89 }
90
91 static void
92 m68k_fill_fpregset (struct regcache *regcache, void *buf)
93 {
94 int i;
95
96 for (i = m68k_num_gregs; i < m68k_num_regs; i++)
97 collect_register (regcache, i, ((char *) buf
98 + (m68k_regmap[i] - m68k_regmap[m68k_num_gregs])));
99 }
100
101 static void
102 m68k_store_fpregset (struct regcache *regcache, const void *buf)
103 {
104 int i;
105
106 for (i = m68k_num_gregs; i < m68k_num_regs; i++)
107 supply_register (regcache, i, ((const char *) buf
108 + (m68k_regmap[i] - m68k_regmap[m68k_num_gregs])));
109 }
110
111 #endif /* HAVE_PTRACE_GETREGS */
112
113 static struct regset_info m68k_regsets[] = {
114 #ifdef HAVE_PTRACE_GETREGS
115 { PTRACE_GETREGS, PTRACE_SETREGS, 0, sizeof (elf_gregset_t),
116 GENERAL_REGS,
117 m68k_fill_gregset, m68k_store_gregset },
118 { PTRACE_GETFPREGS, PTRACE_SETFPREGS, 0, sizeof (elf_fpregset_t),
119 FP_REGS,
120 m68k_fill_fpregset, m68k_store_fpregset },
121 #endif /* HAVE_PTRACE_GETREGS */
122 NULL_REGSET
123 };
124
125 static const gdb_byte m68k_breakpoint[] = { 0x4E, 0x4F };
126 #define m68k_breakpoint_len 2
127
128 /* Implementation of linux_target_ops method "sw_breakpoint_from_kind". */
129
130 static const gdb_byte *
131 m68k_sw_breakpoint_from_kind (int kind, int *size)
132 {
133 *size = m68k_breakpoint_len;
134 return m68k_breakpoint;
135 }
136
137 static int
138 m68k_breakpoint_at (CORE_ADDR pc)
139 {
140 unsigned char c[2];
141
142 read_inferior_memory (pc, c, 2);
143 if (c[0] == 0x4E && c[1] == 0x4F)
144 return 1;
145
146 return 0;
147 }
148
149 #include <asm/ptrace.h>
150
151 #ifdef PTRACE_GET_THREAD_AREA
152 /* Fetch the thread-local storage pointer for libthread_db. */
153
154 ps_err_e
155 ps_get_thread_area (struct ps_prochandle *ph,
156 lwpid_t lwpid, int idx, void **base)
157 {
158 if (ptrace (PTRACE_GET_THREAD_AREA, lwpid, NULL, base) != 0)
159 return PS_ERR;
160
161 /* IDX is the bias from the thread pointer to the beginning of the
162 thread descriptor. It has to be subtracted due to implementation
163 quirks in libthread_db. */
164 *base = (void *) ((char *)*base - idx);
165
166 return PS_OK;
167 }
168 #endif /* PTRACE_GET_THREAD_AREA */
169
170 static struct regsets_info m68k_regsets_info =
171 {
172 m68k_regsets, /* regsets */
173 0, /* num_regsets */
174 NULL, /* disabled_regsets */
175 };
176
177 static struct usrregs_info m68k_usrregs_info =
178 {
179 m68k_num_regs,
180 m68k_regmap,
181 };
182
183 static struct regs_info regs_info =
184 {
185 NULL, /* regset_bitmap */
186 &m68k_usrregs_info,
187 &m68k_regsets_info
188 };
189
190 static const struct regs_info *
191 m68k_regs_info (void)
192 {
193 return &regs_info;
194 }
195
196 static void
197 m68k_arch_setup (void)
198 {
199 current_process ()->tdesc = tdesc_m68k;
200 }
201
202 /* Support for hardware single step. */
203
204 static int
205 m68k_supports_hardware_single_step (void)
206 {
207 return 1;
208 }
209
210 struct linux_target_ops the_low_target = {
211 m68k_arch_setup,
212 m68k_regs_info,
213 m68k_cannot_fetch_register,
214 m68k_cannot_store_register,
215 NULL, /* fetch_register */
216 linux_get_pc_32bit,
217 linux_set_pc_32bit,
218 NULL, /* breakpoint_kind_from_pc */
219 m68k_sw_breakpoint_from_kind,
220 NULL,
221 2,
222 m68k_breakpoint_at,
223 NULL, /* supports_z_point_type */
224 NULL, /* insert_point */
225 NULL, /* remove_point */
226 NULL, /* stopped_by_watchpoint */
227 NULL, /* stopped_data_address */
228 NULL, /* collect_ptrace_register */
229 NULL, /* supply_ptrace_register */
230 NULL, /* siginfo_fixup */
231 NULL, /* new_process */
232 NULL, /* delete_process */
233 NULL, /* new_thread */
234 NULL, /* delete_thread */
235 NULL, /* new_fork */
236 NULL, /* prepare_to_resume */
237 NULL, /* process_qsupported */
238 NULL, /* supports_tracepoints */
239 NULL, /* get_thread_area */
240 NULL, /* install_fast_tracepoint_jump_pad */
241 NULL, /* emit_ops */
242 NULL, /* get_min_fast_tracepoint_insn_len */
243 NULL, /* supports_range_stepping */
244 NULL, /* breakpoint_kind_from_current_state */
245 m68k_supports_hardware_single_step,
246 };
247
248 void
249 initialize_low_arch (void)
250 {
251 /* Initialize the Linux target descriptions. */
252 init_registers_m68k ();
253
254 initialize_regsets_info (&m68k_regsets_info);
255 }
lwpid_t
unsigned int lwpid_t
Definition: gdb_proc_service.h:63
collect_register
void collect_register(struct regcache *regcache, int n, void *buf)
Definition: regcache.c:402
m68k_regmap
static int m68k_regmap[]
Definition: linux-m68k-low.c:34
CORE_ADDR
bfd_vma CORE_ADDR
Definition: common-types.h:41
m68k_supports_hardware_single_step
static int m68k_supports_hardware_single_step(void)
Definition: linux-m68k-low.c:205
m68k_num_regs
#define m68k_num_regs
Definition: linux-m68k-low.c:30
m68k_sw_breakpoint_from_kind
static const gdb_byte * m68k_sw_breakpoint_from_kind(int kind, int *size)
Definition: linux-m68k-low.c:131
ps_prochandle
Definition: gdb_proc_service.h:150
m68k_cannot_store_register
static int m68k_cannot_store_register(int regno)
Definition: linux-m68k-low.c:58
m68k_usrregs_info
static struct usrregs_info m68k_usrregs_info
Definition: linux-m68k-low.c:177
ps_err_e
ps_err_e
Definition: gdb_proc_service.h:51
linux_target_ops
Definition: linux-low.h:128
init_registers_m68k
void init_registers_m68k(void)
process_info::tdesc
const struct target_desc * tdesc
Definition: inferiors.h:67
regcache
Definition: regcache.h:31
m68k_breakpoint
static const gdb_byte m68k_breakpoint[]
Definition: linux-m68k-low.c:125
ptrace
PTRACE_TYPE_RET ptrace()
linux_get_pc_32bit
CORE_ADDR linux_get_pc_32bit(struct regcache *regcache)
Definition: linux-low.c:7411
linux-low.h
ps_get_thread_area
ps_err_e ps_get_thread_area(struct ps_prochandle *, lwpid_t, int, psaddr_t *)
Definition: linux-aarch64-low.c:390
m68k_regsets_info
static struct regsets_info m68k_regsets_info
Definition: linux-m68k-low.c:170
the_low_target
struct linux_target_ops the_low_target
Definition: linux-m68k-low.c:210
regs_info
Definition: linux-low.h:94
initialize_low_arch
void initialize_low_arch(void)
Definition: linux-m68k-low.c:249
read_inferior_memory
int read_inferior_memory(CORE_ADDR memaddr, unsigned char *myaddr, int len)
Definition: target.c:120
m68k_breakpoint_len
#define m68k_breakpoint_len
Definition: linux-m68k-low.c:126
server.h
tdesc_m68k
const struct target_desc * tdesc_m68k
current_process
struct process_info * current_process(void)
Definition: inferiors.c:210
usrregs_info
Definition: linux-low.h:83
PS_ERR
Definition: gdb_proc_service.h:54
m68k_breakpoint_at
static int m68k_breakpoint_at(CORE_ADDR pc)
Definition: linux-m68k-low.c:138
linux_set_pc_32bit
void linux_set_pc_32bit(struct regcache *regcache, CORE_ADDR pc)
Definition: linux-low.c:7400
m68k_regs_info
static const struct regs_info * m68k_regs_info(void)
Definition: linux-m68k-low.c:191
gdb_byte
bfd_byte gdb_byte
Definition: common-types.h:38
target_desc
Definition: tdesc.h:33
m68k_regsets
static struct regset_info m68k_regsets[]
Definition: linux-m68k-low.c:113
PS_OK
Definition: gdb_proc_service.h:53
regs_info
static struct regs_info regs_info
Definition: linux-m68k-low.c:183
gdb_ptrace.h
m68k_cannot_fetch_register
static int m68k_cannot_fetch_register(int regno)
Definition: linux-m68k-low.c:64
PTRACE_GET_THREAD_AREA
#define PTRACE_GET_THREAD_AREA
Definition: linux-arm-low.c:50
m68k_num_gregs
#define m68k_num_gregs
Definition: linux-m68k-low.c:31
supply_register
void supply_register(struct regcache *regcache, int n, const void *buf)
Definition: regcache.c:318
m68k_arch_setup
static void m68k_arch_setup(void)
Definition: linux-m68k-low.c:197