1 /* GNU/Linux/m68k specific low level interface, for the remote server for GDB.
2 Copyright (C) 1995-2024 Free Software Foundation, Inc.
4 This file is part of GDB.
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.
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.
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/>. */
20 #include "linux-low.h"
22 /* Linux target op definitions for the m68k architecture. */
24 class m68k_target
: public linux_process_target
28 const regs_info
*get_regs_info () override
;
30 const gdb_byte
*sw_breakpoint_from_kind (int kind
, int *size
) override
;
34 void low_arch_setup () override
;
36 bool low_cannot_fetch_register (int regno
) override
;
38 bool low_cannot_store_register (int regno
) override
;
40 bool low_supports_breakpoints () override
;
42 CORE_ADDR
low_get_pc (regcache
*regcache
) override
;
44 void low_set_pc (regcache
*regcache
, CORE_ADDR newpc
) override
;
46 int low_decr_pc_after_break () override
;
48 bool low_breakpoint_at (CORE_ADDR pc
) override
;
51 /* The singleton target ops object. */
53 static m68k_target the_m68k_target
;
56 m68k_target::low_supports_breakpoints ()
62 m68k_target::low_get_pc (regcache
*regcache
)
64 return linux_get_pc_32bit (regcache
);
68 m68k_target::low_set_pc (regcache
*regcache
, CORE_ADDR pc
)
70 linux_set_pc_32bit (regcache
, pc
);
74 m68k_target::low_decr_pc_after_break ()
79 /* Defined in auto-generated file reg-m68k.c. */
80 void init_registers_m68k (void);
81 extern const struct target_desc
*tdesc_m68k
;
87 #define m68k_num_regs 29
88 #define m68k_num_gregs 18
90 /* This table must line up with REGISTER_NAMES in tm-m68k.h */
91 static int m68k_regmap
[] =
94 PT_D0
* 4, PT_D1
* 4, PT_D2
* 4, PT_D3
* 4,
95 PT_D4
* 4, PT_D5
* 4, PT_D6
* 4, PT_D7
* 4,
96 PT_A0
* 4, PT_A1
* 4, PT_A2
* 4, PT_A3
* 4,
97 PT_A4
* 4, PT_A5
* 4, PT_A6
* 4, PT_USP
* 4,
100 14 * 4, 0 * 4, 1 * 4, 2 * 4, 3 * 4, 4 * 4, 5 * 4, 6 * 4,
101 7 * 4, 8 * 4, 9 * 4, 10 * 4, 11 * 4, 12 * 4, 13 * 4, 15 * 4,
105 PT_FP0
* 4, PT_FP1
* 4, PT_FP2
* 4, PT_FP3
* 4,
106 PT_FP4
* 4, PT_FP5
* 4, PT_FP6
* 4, PT_FP7
* 4,
107 PT_FPCR
* 4, PT_FPSR
* 4, PT_FPIAR
* 4
109 21 * 4, 24 * 4, 27 * 4, 30 * 4, 33 * 4, 36 * 4,
110 39 * 4, 42 * 4, 45 * 4, 46 * 4, 47 * 4
115 m68k_target::low_cannot_store_register (int regno
)
117 return (regno
>= m68k_num_regs
);
121 m68k_target::low_cannot_fetch_register (int regno
)
123 return (regno
>= m68k_num_regs
);
126 #ifdef HAVE_PTRACE_GETREGS
127 #include <sys/procfs.h>
128 #include "nat/gdb_ptrace.h"
131 m68k_fill_gregset (struct regcache
*regcache
, void *buf
)
135 for (i
= 0; i
< m68k_num_gregs
; i
++)
136 collect_register (regcache
, i
, (char *) buf
+ m68k_regmap
[i
]);
140 m68k_store_gregset (struct regcache
*regcache
, const void *buf
)
144 for (i
= 0; i
< m68k_num_gregs
; i
++)
145 supply_register (regcache
, i
, (const char *) buf
+ m68k_regmap
[i
]);
149 m68k_fill_fpregset (struct regcache
*regcache
, void *buf
)
153 for (i
= m68k_num_gregs
; i
< m68k_num_regs
; i
++)
154 collect_register (regcache
, i
, ((char *) buf
155 + (m68k_regmap
[i
] - m68k_regmap
[m68k_num_gregs
])));
159 m68k_store_fpregset (struct regcache
*regcache
, const void *buf
)
163 for (i
= m68k_num_gregs
; i
< m68k_num_regs
; i
++)
164 supply_register (regcache
, i
, ((const char *) buf
165 + (m68k_regmap
[i
] - m68k_regmap
[m68k_num_gregs
])));
168 #endif /* HAVE_PTRACE_GETREGS */
170 static struct regset_info m68k_regsets
[] = {
171 #ifdef HAVE_PTRACE_GETREGS
172 { PTRACE_GETREGS
, PTRACE_SETREGS
, 0, sizeof (elf_gregset_t
),
174 m68k_fill_gregset
, m68k_store_gregset
},
175 { PTRACE_GETFPREGS
, PTRACE_SETFPREGS
, 0, sizeof (elf_fpregset_t
),
177 m68k_fill_fpregset
, m68k_store_fpregset
},
178 #endif /* HAVE_PTRACE_GETREGS */
182 static const gdb_byte m68k_breakpoint
[] = { 0x4E, 0x4F };
183 #define m68k_breakpoint_len 2
185 /* Implementation of target ops method "sw_breakpoint_from_kind". */
188 m68k_target::sw_breakpoint_from_kind (int kind
, int *size
)
190 *size
= m68k_breakpoint_len
;
191 return m68k_breakpoint
;
195 m68k_target::low_breakpoint_at (CORE_ADDR pc
)
199 read_inferior_memory (pc
, c
, 2);
200 if (c
[0] == 0x4E && c
[1] == 0x4F)
206 #include <asm/ptrace.h>
208 #ifdef PTRACE_GET_THREAD_AREA
209 /* Fetch the thread-local storage pointer for libthread_db. */
212 ps_get_thread_area (struct ps_prochandle
*ph
,
213 lwpid_t lwpid
, int idx
, void **base
)
215 if (ptrace (PTRACE_GET_THREAD_AREA
, lwpid
, NULL
, base
) != 0)
218 /* IDX is the bias from the thread pointer to the beginning of the
219 thread descriptor. It has to be subtracted due to implementation
220 quirks in libthread_db. */
221 *base
= (void *) ((char *)*base
- idx
);
225 #endif /* PTRACE_GET_THREAD_AREA */
227 static struct regsets_info m68k_regsets_info
=
229 m68k_regsets
, /* regsets */
231 NULL
, /* disabled_regsets */
234 static struct usrregs_info m68k_usrregs_info
=
240 static struct regs_info myregs_info
=
242 NULL
, /* regset_bitmap */
248 m68k_target::get_regs_info ()
254 m68k_target::low_arch_setup ()
256 current_process ()->tdesc
= tdesc_m68k
;
259 /* The linux target ops object. */
261 linux_process_target
*the_linux_target
= &the_m68k_target
;
264 initialize_low_arch (void)
266 /* Initialize the Linux target descriptions. */
267 init_registers_m68k ();
269 initialize_regsets_info (&m68k_regsets_info
);