1 /* Target-dependent code for GNU/Linux on Nios II.
2 Copyright (C) 2012-2014 Free Software Foundation, Inc.
3 Contributed by Mentor Graphics, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program 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
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
22 #include "gdb_assert.h"
25 #include "solib-svr4.h"
26 #include "trad-frame.h"
27 #include "tramp-frame.h"
31 #include "linux-tdep.h"
32 #include "glibc-tdep.h"
33 #include "nios2-tdep.h"
35 #include "features/nios2-linux.c"
37 /* Core file and register set support. */
39 /* Map from the normal register enumeration order to the order that
40 registers appear in core files, which corresponds to the order
41 of the register slots in the kernel's struct pt_regs. */
43 static const int reg_offsets[NIOS2_NUM_REGS] =
45 -1, 8, 9, 10, 11, 12, 13, 14, /* r0 - r7 */
46 0, 1, 2, 3, 4, 5, 6, 7, /* r8 - r15 */
47 23, 24, 25, 26, 27, 28, 29, 30, /* r16 - r23 */
48 -1, -1, 19, 18, 17, 21, -1, 16, /* et bt gp sp fp ea sstatus ra */
50 -1, 20, -1, -1, -1, -1, -1, -1, /* status estatus ... */
51 -1, -1, -1, -1, -1, -1, -1, -1
54 /* Implement the supply_regset hook for core files. */
57 nios2_supply_gregset (const struct regset *regset,
58 struct regcache *regcache,
59 int regnum, const void *gregs_buf, size_t len)
61 const gdb_byte *gregs = gregs_buf;
63 static const gdb_byte zero_buf[4] = {0, 0, 0, 0};
65 for (regno = NIOS2_Z_REGNUM; regno <= NIOS2_MPUACC_REGNUM; regno++)
66 if (regnum == -1 || regnum == regno)
68 if (reg_offsets[regno] != -1)
69 regcache_raw_supply (regcache, regno,
70 gregs + 4 * reg_offsets[regno]);
72 regcache_raw_supply (regcache, regno, zero_buf);
76 static const struct regset nios2_core_regset =
83 /* Implement the regset_from_core_section gdbarch method. */
85 static const struct regset *
86 nios2_regset_from_core_section (struct gdbarch *gdbarch,
87 const char *sect_name, size_t sect_size)
89 if (strcmp (sect_name, ".reg") == 0)
90 return &nios2_core_regset;
95 /* Initialize a trad-frame cache corresponding to the tramp-frame.
96 FUNC is the address of the instruction TRAMP[0] in memory. */
99 nios2_linux_rt_sigreturn_init (const struct tramp_frame *self,
100 struct frame_info *next_frame,
101 struct trad_frame_cache *this_cache,
104 CORE_ADDR base = func + 41 * 4;
107 for (i = 0; i < 23; i++)
108 trad_frame_set_reg_addr (this_cache, i + 1, base + i * 4);
109 trad_frame_set_reg_addr (this_cache, NIOS2_RA_REGNUM, base + 23 * 4);
110 trad_frame_set_reg_addr (this_cache, NIOS2_FP_REGNUM, base + 24 * 4);
111 trad_frame_set_reg_addr (this_cache, NIOS2_GP_REGNUM, base + 25 * 4);
112 trad_frame_set_reg_addr (this_cache, NIOS2_PC_REGNUM, base + 27 * 4);
113 trad_frame_set_reg_addr (this_cache, NIOS2_SP_REGNUM, base + 28 * 4);
115 /* Save a frame ID. */
116 trad_frame_set_id (this_cache, frame_id_build (base, func));
119 static struct tramp_frame nios2_linux_rt_sigreturn_tramp_frame =
124 { 0x00800004 | (139 << 6), -1 }, /* movi r2,__NR_rt_sigreturn */
125 { 0x003b683a, -1 }, /* trap */
126 { TRAMP_SENTINEL_INSN }
128 nios2_linux_rt_sigreturn_init
131 /* When FRAME is at a syscall instruction, return the PC of the next
132 instruction to be executed. */
135 nios2_linux_syscall_next_pc (struct frame_info *frame)
137 CORE_ADDR pc = get_frame_pc (frame);
138 ULONGEST syscall_nr = get_frame_register_unsigned (frame, NIOS2_R2_REGNUM);
140 /* If we are about to make a sigreturn syscall, use the unwinder to
141 decode the signal frame. */
142 if (syscall_nr == 139 /* rt_sigreturn */)
143 return frame_unwind_caller_pc (frame);
145 return pc + NIOS2_OPCODE_SIZE;
148 /* Hook function for gdbarch_register_osabi. */
151 nios2_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
153 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
155 linux_init_abi (info, gdbarch);
157 /* Shared library handling. */
158 set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
159 set_gdbarch_skip_solib_resolver (gdbarch, glibc_skip_solib_resolver);
161 set_solib_svr4_fetch_link_map_offsets (gdbarch,
162 svr4_ilp32_fetch_link_map_offsets);
163 /* Enable TLS support. */
164 set_gdbarch_fetch_tls_load_module_address (gdbarch,
165 svr4_fetch_objfile_link_map);
166 /* Core file support. */
167 set_gdbarch_regset_from_core_section (gdbarch,
168 nios2_regset_from_core_section);
169 /* Linux signal frame unwinders. */
170 tramp_frame_prepend_unwinder (gdbarch,
171 &nios2_linux_rt_sigreturn_tramp_frame);
173 tdep->syscall_next_pc = nios2_linux_syscall_next_pc;
175 /* Index of target address word in glibc jmp_buf. */
179 /* Provide a prototype to silence -Wmissing-prototypes. */
181 extern initialize_file_ftype _initialize_nios2_linux_tdep;
184 _initialize_nios2_linux_tdep (void)
186 gdbarch_register_osabi (bfd_arch_nios2, 0, GDB_OSABI_LINUX,
187 nios2_linux_init_abi);
189 initialize_tdesc_nios2_linux ();