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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) 1995-2015 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
59 {
60  return (regno >= m68k_num_regs);
61 }
62 
63 static int
65 {
66  return (regno >= m68k_num_regs);
67 }
68 
69 #ifdef HAVE_PTRACE_GETREGS
70 #include <sys/procfs.h>
71 #include <sys/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  { 0, 0, 0, -1, -1, NULL, NULL }
123 };
124 
125 static const unsigned char m68k_breakpoint[] = { 0x4E, 0x4F };
126 #define m68k_breakpoint_len 2
127 
128 static CORE_ADDR
129 m68k_get_pc (struct regcache *regcache)
130 {
131  unsigned long pc;
132 
133  collect_register_by_name (regcache, "pc", &pc);
134  return pc;
135 }
136 
137 static void
138 m68k_set_pc (struct regcache *regcache, CORE_ADDR value)
139 {
140  unsigned long newpc = value;
141 
142  supply_register_by_name (regcache, "pc", &newpc);
143 }
144 
145 static int
147 {
148  unsigned char c[2];
149 
150  read_inferior_memory (pc, c, 2);
151  if (c[0] == 0x4E && c[1] == 0x4F)
152  return 1;
153 
154  return 0;
155 }
156 
157 #include <asm/ptrace.h>
158 
159 #ifdef PTRACE_GET_THREAD_AREA
160 /* Fetch the thread-local storage pointer for libthread_db. */
161 
162 ps_err_e
163 ps_get_thread_area (const struct ps_prochandle *ph,
164  lwpid_t lwpid, int idx, void **base)
165 {
166  if (ptrace (PTRACE_GET_THREAD_AREA, lwpid, NULL, base) != 0)
167  return PS_ERR;
168 
169  /* IDX is the bias from the thread pointer to the beginning of the
170  thread descriptor. It has to be subtracted due to implementation
171  quirks in libthread_db. */
172  *base = (void *) ((char *)*base - idx);
173 
174  return PS_OK;
175 }
176 #endif /* PTRACE_GET_THREAD_AREA */
177 
178 static struct regsets_info m68k_regsets_info =
179  {
180  m68k_regsets, /* regsets */
181  0, /* num_regsets */
182  NULL, /* disabled_regsets */
183  };
184 
185 static struct usrregs_info m68k_usrregs_info =
186  {
188  m68k_regmap,
189  };
190 
191 static struct regs_info regs_info =
192  {
193  NULL, /* regset_bitmap */
195  &m68k_regsets_info
196  };
197 
198 static const struct regs_info *
200 {
201  return &regs_info;
202 }
203 
204 static void
206 {
208 }
209 
210 struct linux_target_ops the_low_target = {
215  NULL, /* fetch_register */
216  m68k_get_pc,
217  m68k_set_pc,
220  NULL,
221  2,
223 };
224 
225 void
227 {
228  /* Initialize the Linux target descriptions. */
230 
231  initialize_regsets_info (&m68k_regsets_info);
232 }
unsigned int lwpid_t
void collect_register(struct regcache *regcache, int n, void *buf)
Definition: regcache.c:414
static int m68k_regmap[]
bfd_vma CORE_ADDR
Definition: common-types.h:41
void supply_register_by_name(struct regcache *regcache, const char *name, const void *buf)
Definition: regcache.c:405
#define m68k_num_regs
static int m68k_cannot_store_register(int regno)
static struct usrregs_info m68k_usrregs_info
ps_err_e
void init_registers_m68k(void)
const struct target_desc * tdesc
Definition: inferiors.h:69
void collect_register_by_name(struct regcache *regcache, const char *name, void *buf)
Definition: regcache.c:430
void initialize_low_arch(void)
int read_inferior_memory(CORE_ADDR memaddr, unsigned char *myaddr, int len)
Definition: target.c:43
#define m68k_breakpoint_len
static void m68k_set_pc(struct regcache *regcache, CORE_ADDR value)
const struct target_desc * tdesc_m68k
struct process_info * current_process(void)
Definition: inferiors.c:356
static const unsigned char m68k_breakpoint[]
static int m68k_breakpoint_at(CORE_ADDR pc)
static const struct regs_info * m68k_regs_info(void)
static struct regset_info m68k_regsets[]
static struct regs_info regs_info
ps_err_e ps_get_thread_area(const struct ps_prochandle *, lwpid_t, int, psaddr_t *)
static int m68k_cannot_fetch_register(int regno)
#define PTRACE_GET_THREAD_AREA
Definition: linux-arm-low.c:47
#define m68k_num_gregs
void supply_register(struct regcache *regcache, int n, const void *buf)
Definition: regcache.c:330
static CORE_ADDR m68k_get_pc(struct regcache *regcache)
static void m68k_arch_setup(void)