1 /* This file defines the interface between the simulator and gdb. 2 3 Copyright (C) 1993-2024 Free Software Foundation, Inc. 4 5 This file is part of GDB. 6 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. 11 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. 16 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/>. */ 19 20 #ifndef SIM_SIM_H 21 #define SIM_SIM_H 1 22 23 #include <stdbool.h> 24 #include <stdint.h> 25 26 #ifdef __cplusplus 27 extern "C" { 28 #endif 29 30 /* Semi-opaque type used as result of sim_open and passed back to all 31 other routines. "desc" is short for "descriptor". 32 It is up to each simulator to define `sim_state'. */ 33 34 typedef struct sim_state *SIM_DESC; 35 36 37 /* Values for `kind' arg to sim_open. */ 38 39 typedef enum { 40 SIM_OPEN_STANDALONE, /* simulator used standalone (run.c) */ 41 SIM_OPEN_DEBUG /* simulator used by debugger (gdb) */ 42 } SIM_OPEN_KIND; 43 44 45 /* Return codes from various functions. */ 46 47 typedef enum { 48 SIM_RC_FAIL = 0, 49 SIM_RC_OK = 1 50 } SIM_RC; 51 52 53 /* Some structs, as opaque types. */ 54 55 struct bfd; 56 struct host_callback_struct; 57 58 59 /* Main simulator entry points. */ 60 61 62 /* Create a fully initialized simulator instance. 63 64 (This function is called when the simulator is selected from the 65 gdb command line.) 66 67 KIND specifies how the simulator shall be used. Currently there 68 are only two kinds: stand-alone and debug. 69 70 CALLBACK specifies a standard host callback (defined in callback.h). 71 72 ABFD, when non NULL, designates a target program. The program is 73 not loaded. 74 75 ARGV is a standard ARGV pointer such as that passed from the 76 command line. The syntax of the argument list is is assumed to be 77 ``SIM-PROG { SIM-OPTION } [ TARGET-PROGRAM { TARGET-OPTION } ]''. 78 The trailing TARGET-PROGRAM and args are only valid for a 79 stand-alone simulator. 80 81 On success, the result is a non NULL descriptor that shall be 82 passed to the other sim_foo functions. While the simulator 83 configuration can be parameterized by (in decreasing precedence) 84 ARGV's SIM-OPTION, ARGV's TARGET-PROGRAM and the ABFD argument, the 85 successful creation of the simulator shall not dependent on the 86 presence of any of these arguments/options. 87 88 Hardware simulator: The created simulator shall be sufficiently 89 initialized to handle, with out restrictions any client requests 90 (including memory reads/writes, register fetch/stores and a 91 resume). 92 93 Process simulator: that process is not created until a call to 94 sim_create_inferior. FIXME: What should the state of the simulator 95 be? */ 96 97 SIM_DESC sim_open (SIM_OPEN_KIND kind, struct host_callback_struct *callback, 98 struct bfd *abfd, char * const *argv); 99 100 101 /* Destory a simulator instance. 102 103 QUITTING is non-zero if we cannot hang on errors. 104 105 This may involve freeing target memory and closing any open files 106 and mmap'd areas. You cannot assume sim_kill has already been 107 called. */ 108 109 void sim_close (SIM_DESC sd, int quitting); 110 111 112 /* Load program PROG into the simulators memory. 113 114 If ABFD is non-NULL, the bfd for the file has already been opened. 115 The result is a return code indicating success. 116 117 Hardware simulator: Normally, each program section is written into 118 memory according to that sections LMA using physical (direct) 119 addressing. The exception being systems, such as PPC/CHRP, which 120 support more complicated program loaders. A call to this function 121 should not effect the state of the processor registers. Multiple 122 calls to this function are permitted and have an accumulative 123 effect. 124 125 Process simulator: Calls to this function may be ignored. 126 127 FIXME: Most hardware simulators load the image at the VMA using 128 virtual addressing. 129 130 FIXME: For some hardware targets, before a loaded program can be 131 executed, it requires the manipulation of VM registers and tables. 132 Such manipulation should probably (?) occure in 133 sim_create_inferior. */ 134 135 SIM_RC sim_load (SIM_DESC sd, const char *prog, struct bfd *abfd, int from_tty); 136 137 138 /* Prepare to run the simulated program. 139 140 ABFD, if not NULL, provides initial processor state information. 141 ARGV and ENV, if non NULL, are NULL terminated lists of pointers. 142 143 Hardware simulator: This function shall initialize the processor 144 registers to a known value. The program counter and possibly stack 145 pointer shall be set using information obtained from ABFD (or 146 hardware reset defaults). ARGV and ENV, dependant on the target 147 ABI, may be written to memory. 148 149 Process simulator: After a call to this function, a new process 150 instance shall exist. The TEXT, DATA, BSS and stack regions shall 151 all be initialized, ARGV and ENV shall be written to process 152 address space (according to the applicable ABI) and the program 153 counter and stack pointer set accordingly. */ 154 155 SIM_RC sim_create_inferior (SIM_DESC sd, struct bfd *abfd, 156 char * const *argv, char * const *env); 157 158 159 /* Fetch LENGTH bytes of the simulated program's memory. Start fetch 160 at virtual address MEM and store in BUF. Result is number of bytes 161 read, or zero if error. */ 162 163 uint64_t sim_read (SIM_DESC sd, uint64_t mem, void *buf, uint64_t length); 164 165 166 /* Store LENGTH bytes from BUF into the simulated program's 167 memory. Store bytes starting at virtual address MEM. Result is 168 number of bytes write, or zero if error. */ 169 170 uint64_t sim_write (SIM_DESC sd, uint64_t mem, const void *buf, uint64_t length); 171 172 173 /* Fetch register REGNO storing its raw (target endian) value in the 174 LENGTH byte buffer BUF. Return the actual size of the register or 175 zero if REGNO is not applicable. 176 177 Legacy implementations ignore LENGTH and always return -1. 178 179 If LENGTH does not match the size of REGNO no data is transfered 180 (the actual register size is still returned). */ 181 182 int sim_fetch_register (SIM_DESC sd, int regno, void *buf, int length); 183 184 185 /* Store register REGNO from the raw (target endian) value in BUF. 186 187 Return the actual size of the register, any size not equal to 188 LENGTH indicates the register was not updated correctly. 189 190 Return a LENGTH of -1 to indicate the register was not updated 191 and an error has occurred. 192 193 Return a LENGTH of 0 to indicate the register was not updated 194 but no error has occurred. */ 195 196 int sim_store_register (SIM_DESC sd, int regno, const void *buf, int length); 197 198 199 /* Print whatever statistics the simulator has collected. 200 201 When VERBOSE is enabled, extra details will be shown. */ 202 203 void sim_info (SIM_DESC sd, bool verbose); 204 205 206 /* Return a memory map in XML format. 207 208 The caller must free the returned string. 209 210 For details on the format, see GDB's Memory Map Format documentation. */ 211 212 char *sim_memory_map (SIM_DESC sd); 213 214 215 /* Run (or resume) the simulated program. 216 217 STEP, when non-zero indicates that only a single simulator cycle 218 should be emulated. 219 220 SIGGNAL, if non-zero is a (HOST) SIGRC value indicating the type of 221 event (hardware interrupt, signal) to be delivered to the simulated 222 program. 223 224 Hardware simulator: If the SIGRC value returned by 225 sim_stop_reason() is passed back to the simulator via SIGGNAL then 226 the hardware simulator shall correctly deliver the hardware event 227 indicated by that signal. If a value of zero is passed in then the 228 simulation will continue as if there were no outstanding signal. 229 The effect of any other SIGGNAL value is is implementation 230 dependant. 231 232 Process simulator: If SIGRC is non-zero then the corresponding 233 signal is delivered to the simulated program and execution is then 234 continued. A zero SIGRC value indicates that the program should 235 continue as normal. */ 236 237 void sim_resume (SIM_DESC sd, int step, int siggnal); 238 239 240 /* Asynchronous request to stop the simulation. 241 A nonzero return indicates that the simulator is able to handle 242 the request */ 243 244 int sim_stop (SIM_DESC sd); 245 246 247 /* Fetch the REASON why the program stopped. 248 249 SIM_EXITED: The program has terminated. SIGRC indicates the target 250 dependant exit status. 251 252 SIM_STOPPED: The program has stopped. SIGRC uses the host's signal 253 numbering as a way of identifying the reaon: program interrupted by 254 user via a sim_stop request (SIGINT); a breakpoint instruction 255 (SIGTRAP); a completed single step (SIGTRAP); an internal error 256 condition (SIGABRT); an illegal instruction (SIGILL); Access to an 257 undefined memory region (SIGSEGV); Mis-aligned memory access 258 (SIGBUS). For some signals information in addition to the signal 259 number may be retained by the simulator (e.g. offending address), 260 that information is not directly accessable via this interface. 261 262 SIM_SIGNALLED: The program has been terminated by a signal. The 263 simulator has encountered target code that causes the program 264 to exit with signal SIGRC. 265 266 SIM_RUNNING, SIM_POLLING: The return of one of these values 267 indicates a problem internal to the simulator. */ 268 269 enum sim_stop { sim_running, sim_polling, sim_exited, sim_stopped, sim_signalled }; 270 271 void sim_stop_reason (SIM_DESC sd, enum sim_stop *reason, int *sigrc); 272 273 274 /* Passthru for other commands that the simulator might support. 275 Simulators should be prepared to deal with any combination of NULL 276 or empty CMD. */ 277 278 void sim_do_command (SIM_DESC sd, const char *cmd); 279 280 /* Complete a command based on the available sim commands. Returns an 281 array of possible matches. */ 282 283 char **sim_complete_command (SIM_DESC sd, const char *text, const char *word); 284 285 #ifdef __cplusplus 286 } 287 #endif 288 289 #endif /* !defined (SIM_SIM_H) */ 290