1 /* This file defines the interface between the simulator and gdb. 2 3 Copyright (C) 1993-2022 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 #ifdef __cplusplus 24 extern "C" { 25 #endif 26 27 /* This file is used when building stand-alone simulators, so isolate this 28 file from gdb. */ 29 30 typedef unsigned int SIM_ADDR; 31 32 33 /* Semi-opaque type used as result of sim_open and passed back to all 34 other routines. "desc" is short for "descriptor". 35 It is up to each simulator to define `sim_state'. */ 36 37 typedef struct sim_state *SIM_DESC; 38 39 40 /* Values for `kind' arg to sim_open. */ 41 42 typedef enum { 43 SIM_OPEN_STANDALONE, /* simulator used standalone (run.c) */ 44 SIM_OPEN_DEBUG /* simulator used by debugger (gdb) */ 45 } SIM_OPEN_KIND; 46 47 48 /* Return codes from various functions. */ 49 50 typedef enum { 51 SIM_RC_FAIL = 0, 52 SIM_RC_OK = 1 53 } SIM_RC; 54 55 56 /* Some structs, as opaque types. */ 57 58 struct bfd; 59 struct host_callback_struct; 60 61 62 /* Main simulator entry points. */ 63 64 65 /* Create a fully initialized simulator instance. 66 67 (This function is called when the simulator is selected from the 68 gdb command line.) 69 70 KIND specifies how the simulator shall be used. Currently there 71 are only two kinds: stand-alone and debug. 72 73 CALLBACK specifies a standard host callback (defined in callback.h). 74 75 ABFD, when non NULL, designates a target program. The program is 76 not loaded. 77 78 ARGV is a standard ARGV pointer such as that passed from the 79 command line. The syntax of the argument list is is assumed to be 80 ``SIM-PROG { SIM-OPTION } [ TARGET-PROGRAM { TARGET-OPTION } ]''. 81 The trailing TARGET-PROGRAM and args are only valid for a 82 stand-alone simulator. 83 84 On success, the result is a non NULL descriptor that shall be 85 passed to the other sim_foo functions. While the simulator 86 configuration can be parameterized by (in decreasing precedence) 87 ARGV's SIM-OPTION, ARGV's TARGET-PROGRAM and the ABFD argument, the 88 successful creation of the simulator shall not dependent on the 89 presence of any of these arguments/options. 90 91 Hardware simulator: The created simulator shall be sufficiently 92 initialized to handle, with out restrictions any client requests 93 (including memory reads/writes, register fetch/stores and a 94 resume). 95 96 Process simulator: that process is not created until a call to 97 sim_create_inferior. FIXME: What should the state of the simulator 98 be? */ 99 100 SIM_DESC sim_open (SIM_OPEN_KIND kind, struct host_callback_struct *callback, 101 struct bfd *abfd, char * const *argv); 102 103 104 /* Destory a simulator instance. 105 106 QUITTING is non-zero if we cannot hang on errors. 107 108 This may involve freeing target memory and closing any open files 109 and mmap'd areas. You cannot assume sim_kill has already been 110 called. */ 111 112 void sim_close (SIM_DESC sd, int quitting); 113 114 115 /* Load program PROG into the simulators memory. 116 117 If ABFD is non-NULL, the bfd for the file has already been opened. 118 The result is a return code indicating success. 119 120 Hardware simulator: Normally, each program section is written into 121 memory according to that sections LMA using physical (direct) 122 addressing. The exception being systems, such as PPC/CHRP, which 123 support more complicated program loaders. A call to this function 124 should not effect the state of the processor registers. Multiple 125 calls to this function are permitted and have an accumulative 126 effect. 127 128 Process simulator: Calls to this function may be ignored. 129 130 FIXME: Most hardware simulators load the image at the VMA using 131 virtual addressing. 132 133 FIXME: For some hardware targets, before a loaded program can be 134 executed, it requires the manipulation of VM registers and tables. 135 Such manipulation should probably (?) occure in 136 sim_create_inferior. */ 137 138 SIM_RC sim_load (SIM_DESC sd, const char *prog, struct bfd *abfd, int from_tty); 139 140 141 /* Prepare to run the simulated program. 142 143 ABFD, if not NULL, provides initial processor state information. 144 ARGV and ENV, if non NULL, are NULL terminated lists of pointers. 145 146 Hardware simulator: This function shall initialize the processor 147 registers to a known value. The program counter and possibly stack 148 pointer shall be set using information obtained from ABFD (or 149 hardware reset defaults). ARGV and ENV, dependant on the target 150 ABI, may be written to memory. 151 152 Process simulator: After a call to this function, a new process 153 instance shall exist. The TEXT, DATA, BSS and stack regions shall 154 all be initialized, ARGV and ENV shall be written to process 155 address space (according to the applicable ABI) and the program 156 counter and stack pointer set accordingly. */ 157 158 SIM_RC sim_create_inferior (SIM_DESC sd, struct bfd *abfd, 159 char * const *argv, char * const *env); 160 161 162 /* Fetch LENGTH bytes of the simulated program's memory. Start fetch 163 at virtual address MEM and store in BUF. Result is number of bytes 164 read, or zero if error. */ 165 166 int sim_read (SIM_DESC sd, SIM_ADDR mem, void *buf, int length); 167 168 169 /* Store LENGTH bytes from BUF into the simulated program's 170 memory. Store bytes starting at virtual address MEM. Result is 171 number of bytes write, or zero if error. */ 172 173 int sim_write (SIM_DESC sd, SIM_ADDR mem, const void *buf, int length); 174 175 176 /* Fetch register REGNO storing its raw (target endian) value in the 177 LENGTH byte buffer BUF. Return the actual size of the register or 178 zero if REGNO is not applicable. 179 180 Legacy implementations ignore LENGTH and always return -1. 181 182 If LENGTH does not match the size of REGNO no data is transfered 183 (the actual register size is still returned). */ 184 185 int sim_fetch_register (SIM_DESC sd, int regno, void *buf, int length); 186 187 188 /* Store register REGNO from the raw (target endian) value in BUF. 189 190 Return the actual size of the register, any size not equal to 191 LENGTH indicates the register was not updated correctly. 192 193 Return a LENGTH of -1 to indicate the register was not updated 194 and an error has occurred. 195 196 Return a LENGTH of 0 to indicate the register was not updated 197 but no error has occurred. */ 198 199 int sim_store_register (SIM_DESC sd, int regno, const void *buf, int length); 200 201 202 /* Print whatever statistics the simulator has collected. 203 204 VERBOSE is currently unused and must always be zero. */ 205 206 void sim_info (SIM_DESC sd, int verbose); 207 208 209 /* Return a memory map in XML format. 210 211 The caller must free the returned string. 212 213 For details on the format, see GDB's Memory Map Format documentation. */ 214 215 char *sim_memory_map (SIM_DESC sd); 216 217 218 /* Run (or resume) the simulated program. 219 220 STEP, when non-zero indicates that only a single simulator cycle 221 should be emulated. 222 223 SIGGNAL, if non-zero is a (HOST) SIGRC value indicating the type of 224 event (hardware interrupt, signal) to be delivered to the simulated 225 program. 226 227 Hardware simulator: If the SIGRC value returned by 228 sim_stop_reason() is passed back to the simulator via SIGGNAL then 229 the hardware simulator shall correctly deliver the hardware event 230 indicated by that signal. If a value of zero is passed in then the 231 simulation will continue as if there were no outstanding signal. 232 The effect of any other SIGGNAL value is is implementation 233 dependant. 234 235 Process simulator: If SIGRC is non-zero then the corresponding 236 signal is delivered to the simulated program and execution is then 237 continued. A zero SIGRC value indicates that the program should 238 continue as normal. */ 239 240 void sim_resume (SIM_DESC sd, int step, int siggnal); 241 242 243 /* Asynchronous request to stop the simulation. 244 A nonzero return indicates that the simulator is able to handle 245 the request */ 246 247 int sim_stop (SIM_DESC sd); 248 249 250 /* Fetch the REASON why the program stopped. 251 252 SIM_EXITED: The program has terminated. SIGRC indicates the target 253 dependant exit status. 254 255 SIM_STOPPED: The program has stopped. SIGRC uses the host's signal 256 numbering as a way of identifying the reaon: program interrupted by 257 user via a sim_stop request (SIGINT); a breakpoint instruction 258 (SIGTRAP); a completed single step (SIGTRAP); an internal error 259 condition (SIGABRT); an illegal instruction (SIGILL); Access to an 260 undefined memory region (SIGSEGV); Mis-aligned memory access 261 (SIGBUS). For some signals information in addition to the signal 262 number may be retained by the simulator (e.g. offending address), 263 that information is not directly accessable via this interface. 264 265 SIM_SIGNALLED: The program has been terminated by a signal. The 266 simulator has encountered target code that causes the program 267 to exit with signal SIGRC. 268 269 SIM_RUNNING, SIM_POLLING: The return of one of these values 270 indicates a problem internal to the simulator. */ 271 272 enum sim_stop { sim_running, sim_polling, sim_exited, sim_stopped, sim_signalled }; 273 274 void sim_stop_reason (SIM_DESC sd, enum sim_stop *reason, int *sigrc); 275 276 277 /* Passthru for other commands that the simulator might support. 278 Simulators should be prepared to deal with any combination of NULL 279 or empty CMD. */ 280 281 void sim_do_command (SIM_DESC sd, const char *cmd); 282 283 /* Complete a command based on the available sim commands. Returns an 284 array of possible matches. */ 285 286 char **sim_complete_command (SIM_DESC sd, const char *text, const char *word); 287 288 #ifdef __cplusplus 289 } 290 #endif 291 292 #endif /* !defined (SIM_SIM_H) */ 293