| 1 | /* Target-dependent code for GNU/Linux on OpenRISC processors. |
| 2 | Copyright (C) 2018-2021 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 "defs.h" |
| 20 | #include "or1k-tdep.h" |
| 21 | #include "osabi.h" |
| 22 | #include "glibc-tdep.h" |
| 23 | #include "linux-tdep.h" |
| 24 | #include "solib-svr4.h" |
| 25 | #include "regset.h" |
| 26 | #include "tramp-frame.h" |
| 27 | #include "trad-frame.h" |
| 28 | #include "gdbarch.h" |
| 29 | |
| 30 | /* Define the general register mapping. The kernel puts the PC at offset 0, |
| 31 | gdb puts it at offset 32. Register x0 is always 0 and can be ignored. |
| 32 | Registers x1 to x31 are in the same place. */ |
| 33 | |
| 34 | static const struct regcache_map_entry or1k_linux_gregmap[] = |
| 35 | { |
| 36 | { 32, OR1K_ZERO_REGNUM, 4 }, /* r0 to r31 */ |
| 37 | { 1, OR1K_NPC_REGNUM, 4 }, |
| 38 | { 0 } |
| 39 | }; |
| 40 | |
| 41 | /* Define the general register regset. */ |
| 42 | |
| 43 | static const struct regset or1k_linux_gregset = |
| 44 | { |
| 45 | or1k_linux_gregmap, regcache_supply_regset, regcache_collect_regset |
| 46 | }; |
| 47 | |
| 48 | /* Define hook for core file support. */ |
| 49 | |
| 50 | static void |
| 51 | or1k_linux_iterate_over_regset_sections (struct gdbarch *gdbarch, |
| 52 | iterate_over_regset_sections_cb *cb, |
| 53 | void *cb_data, |
| 54 | const struct regcache *regcache) |
| 55 | { |
| 56 | cb (".reg", (33 * 4), (33 * 4), &or1k_linux_gregset, NULL, cb_data); |
| 57 | } |
| 58 | |
| 59 | /* Signal trampoline support. */ |
| 60 | |
| 61 | static void or1k_linux_sigframe_init (const struct tramp_frame *self, |
| 62 | struct frame_info *this_frame, |
| 63 | struct trad_frame_cache *this_cache, |
| 64 | CORE_ADDR func); |
| 65 | |
| 66 | #define OR1K_RT_SIGRETURN 139 |
| 67 | |
| 68 | #define OR1K_INST_L_ORI_R11_R0_IMM 0xa9600000 |
| 69 | #define OR1K_INST_L_SYS_1 0x20000001 |
| 70 | #define OR1K_INST_L_NOP 0x15000000 |
| 71 | |
| 72 | static const struct tramp_frame or1k_linux_sigframe = { |
| 73 | SIGTRAMP_FRAME, |
| 74 | 4, |
| 75 | { |
| 76 | { OR1K_INST_L_ORI_R11_R0_IMM | OR1K_RT_SIGRETURN, ULONGEST_MAX }, |
| 77 | { OR1K_INST_L_SYS_1, ULONGEST_MAX }, |
| 78 | { OR1K_INST_L_NOP, ULONGEST_MAX }, |
| 79 | { TRAMP_SENTINEL_INSN } |
| 80 | }, |
| 81 | or1k_linux_sigframe_init, |
| 82 | NULL |
| 83 | }; |
| 84 | |
| 85 | /* Runtime signal frames look like this: |
| 86 | struct rt_sigframe { |
| 87 | struct siginfo info; |
| 88 | struct ucontext uc; |
| 89 | unsigned char retcode[16]; |
| 90 | }; |
| 91 | |
| 92 | struct ucontext { |
| 93 | unsigned long uc_flags; - 4 |
| 94 | struct ucontext *uc_link; - 4 |
| 95 | stack_t uc_stack; - 4 * 3 |
| 96 | struct sigcontext uc_mcontext; |
| 97 | sigset_t uc_sigmask; |
| 98 | }; |
| 99 | |
| 100 | struct sigcontext { |
| 101 | struct user_regs_struct regs; |
| 102 | unsigned long oldmask; |
| 103 | }; |
| 104 | |
| 105 | struct user_regs_struct { |
| 106 | unsigned long gpr[32]; |
| 107 | unsigned long pc; |
| 108 | unsigned long sr; |
| 109 | }; */ |
| 110 | |
| 111 | #define SIGFRAME_SIGINFO_SIZE 128 |
| 112 | #define UCONTEXT_MCONTEXT_OFFSET 20 |
| 113 | |
| 114 | static void |
| 115 | or1k_linux_sigframe_init (const struct tramp_frame *self, |
| 116 | struct frame_info *this_frame, |
| 117 | struct trad_frame_cache *this_cache, |
| 118 | CORE_ADDR func) |
| 119 | { |
| 120 | CORE_ADDR frame_sp = get_frame_sp (this_frame); |
| 121 | CORE_ADDR mcontext_base; |
| 122 | CORE_ADDR regs_base; |
| 123 | |
| 124 | mcontext_base = frame_sp + SIGFRAME_SIGINFO_SIZE + UCONTEXT_MCONTEXT_OFFSET; |
| 125 | |
| 126 | /* Handle the general registers 0-31 followed by the PC. */ |
| 127 | regs_base = mcontext_base; |
| 128 | for (int i = 0; i < 32; i++) |
| 129 | trad_frame_set_reg_addr (this_cache, OR1K_ZERO_REGNUM + i, |
| 130 | regs_base + (i * 4)); |
| 131 | trad_frame_set_reg_addr (this_cache, OR1K_NPC_REGNUM, regs_base + (32 * 4)); |
| 132 | trad_frame_set_reg_addr (this_cache, OR1K_SR_REGNUM, regs_base + (33 * 4)); |
| 133 | |
| 134 | /* Choice of the bottom of the sigframe is somewhat arbitrary. */ |
| 135 | trad_frame_set_id (this_cache, frame_id_build (frame_sp, func)); |
| 136 | } |
| 137 | |
| 138 | /* Initialize OpenRISC Linux ABI info. */ |
| 139 | |
| 140 | static void |
| 141 | or1k_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| 142 | { |
| 143 | linux_init_abi (info, gdbarch, 0); |
| 144 | |
| 145 | set_solib_svr4_fetch_link_map_offsets (gdbarch, |
| 146 | svr4_ilp32_fetch_link_map_offsets); |
| 147 | |
| 148 | /* GNU/Linux uses SVR4-style shared libraries. */ |
| 149 | set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target); |
| 150 | |
| 151 | /* GNU/Linux uses the dynamic linker included in the GNU C Library. */ |
| 152 | set_gdbarch_skip_solib_resolver (gdbarch, glibc_skip_solib_resolver); |
| 153 | |
| 154 | /* Enable TLS support. */ |
| 155 | set_gdbarch_fetch_tls_load_module_address (gdbarch, |
| 156 | svr4_fetch_objfile_link_map); |
| 157 | |
| 158 | set_gdbarch_iterate_over_regset_sections |
| 159 | (gdbarch, or1k_linux_iterate_over_regset_sections); |
| 160 | |
| 161 | tramp_frame_prepend_unwinder (gdbarch, &or1k_linux_sigframe); |
| 162 | } |
| 163 | |
| 164 | /* Initialize OpenRISC Linux target support. */ |
| 165 | |
| 166 | void _initialize_or1k_linux_tdep (); |
| 167 | void |
| 168 | _initialize_or1k_linux_tdep () |
| 169 | { |
| 170 | gdbarch_register_osabi (bfd_arch_or1k, 0, GDB_OSABI_LINUX, |
| 171 | or1k_linux_init_abi); |
| 172 | } |