1 /* This file defines the interface between the simulator and gdb. 2 3 Copyright (C) 1993-2021 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 /* Pick up CORE_ADDR_TYPE if defined (from gdb), otherwise use same value as 31 gdb does (unsigned int - from defs.h). */ 32 33 #ifndef CORE_ADDR_TYPE 34 typedef unsigned int SIM_ADDR; 35 #else 36 typedef CORE_ADDR_TYPE SIM_ADDR; 37 #endif 38 39 40 /* Semi-opaque type used as result of sim_open and passed back to all 41 other routines. "desc" is short for "descriptor". 42 It is up to each simulator to define `sim_state'. */ 43 44 typedef struct sim_state *SIM_DESC; 45 46 47 /* Values for `kind' arg to sim_open. */ 48 49 typedef enum { 50 SIM_OPEN_STANDALONE, /* simulator used standalone (run.c) */ 51 SIM_OPEN_DEBUG /* simulator used by debugger (gdb) */ 52 } SIM_OPEN_KIND; 53 54 55 /* Return codes from various functions. */ 56 57 typedef enum { 58 SIM_RC_FAIL = 0, 59 SIM_RC_OK = 1 60 } SIM_RC; 61 62 63 /* Some structs, as opaque types. */ 64 65 struct bfd; 66 struct host_callback_struct; 67 68 69 /* Main simulator entry points. */ 70 71 72 /* Create a fully initialized simulator instance. 73 74 (This function is called when the simulator is selected from the 75 gdb command line.) 76 77 KIND specifies how the simulator shall be used. Currently there 78 are only two kinds: stand-alone and debug. 79 80 CALLBACK specifies a standard host callback (defined in callback.h). 81 82 ABFD, when non NULL, designates a target program. The program is 83 not loaded. 84 85 ARGV is a standard ARGV pointer such as that passed from the 86 command line. The syntax of the argument list is is assumed to be 87 ``SIM-PROG { SIM-OPTION } [ TARGET-PROGRAM { TARGET-OPTION } ]''. 88 The trailing TARGET-PROGRAM and args are only valid for a 89 stand-alone simulator. 90 91 On success, the result is a non NULL descriptor that shall be 92 passed to the other sim_foo functions. While the simulator 93 configuration can be parameterized by (in decreasing precedence) 94 ARGV's SIM-OPTION, ARGV's TARGET-PROGRAM and the ABFD argument, the 95 successful creation of the simulator shall not dependent on the 96 presence of any of these arguments/options. 97 98 Hardware simulator: The created simulator shall be sufficiently 99 initialized to handle, with out restrictions any client requests 100 (including memory reads/writes, register fetch/stores and a 101 resume). 102 103 Process simulator: that process is not created until a call to 104 sim_create_inferior. FIXME: What should the state of the simulator 105 be? */ 106 107 SIM_DESC sim_open (SIM_OPEN_KIND kind, struct host_callback_struct *callback, 108 struct bfd *abfd, char * const *argv); 109 110 111 /* Destory a simulator instance. 112 113 QUITTING is non-zero if we cannot hang on errors. 114 115 This may involve freeing target memory and closing any open files 116 and mmap'd areas. You cannot assume sim_kill has already been 117 called. */ 118 119 void sim_close (SIM_DESC sd, int quitting); 120 121 122 /* Load program PROG into the simulators memory. 123 124 If ABFD is non-NULL, the bfd for the file has already been opened. 125 The result is a return code indicating success. 126 127 Hardware simulator: Normally, each program section is written into 128 memory according to that sections LMA using physical (direct) 129 addressing. The exception being systems, such as PPC/CHRP, which 130 support more complicated program loaders. A call to this function 131 should not effect the state of the processor registers. Multiple 132 calls to this function are permitted and have an accumulative 133 effect. 134 135 Process simulator: Calls to this function may be ignored. 136 137 FIXME: Most hardware simulators load the image at the VMA using 138 virtual addressing. 139 140 FIXME: For some hardware targets, before a loaded program can be 141 executed, it requires the manipulation of VM registers and tables. 142 Such manipulation should probably (?) occure in 143 sim_create_inferior. */ 144 145 SIM_RC sim_load (SIM_DESC sd, const char *prog, struct bfd *abfd, int from_tty); 146 147 148 /* Prepare to run the simulated program. 149 150 ABFD, if not NULL, provides initial processor state information. 151 ARGV and ENV, if non NULL, are NULL terminated lists of pointers. 152 153 Hardware simulator: This function shall initialize the processor 154 registers to a known value. The program counter and possibly stack 155 pointer shall be set using information obtained from ABFD (or 156 hardware reset defaults). ARGV and ENV, dependant on the target 157 ABI, may be written to memory. 158 159 Process simulator: After a call to this function, a new process 160 instance shall exist. The TEXT, DATA, BSS and stack regions shall 161 all be initialized, ARGV and ENV shall be written to process 162 address space (according to the applicable ABI) and the program 163 counter and stack pointer set accordingly. */ 164 165 SIM_RC sim_create_inferior (SIM_DESC sd, struct bfd *abfd, 166 char * const *argv, char * const *env); 167 168 169 /* Fetch LENGTH bytes of the simulated program's memory. Start fetch 170 at virtual address MEM and store in BUF. Result is number of bytes 171 read, or zero if error. */ 172 173 int sim_read (SIM_DESC sd, SIM_ADDR mem, unsigned char *buf, int length); 174 175 176 /* Store LENGTH bytes from BUF into the simulated program's 177 memory. Store bytes starting at virtual address MEM. Result is 178 number of bytes write, or zero if error. */ 179 180 int sim_write (SIM_DESC sd, SIM_ADDR mem, const unsigned char *buf, int length); 181 182 183 /* Fetch register REGNO storing its raw (target endian) value in the 184 LENGTH byte buffer BUF. Return the actual size of the register or 185 zero if REGNO is not applicable. 186 187 Legacy implementations ignore LENGTH and always return -1. 188 189 If LENGTH does not match the size of REGNO no data is transfered 190 (the actual register size is still returned). */ 191 192 int sim_fetch_register (SIM_DESC sd, int regno, unsigned char *buf, int length); 193 194 195 /* Store register REGNO from the raw (target endian) value in BUF. 196 197 Return the actual size of the register, any size not equal to 198 LENGTH indicates the register was not updated correctly. 199 200 Return a LENGTH of -1 to indicate the register was not updated 201 and an error has occurred. 202 203 Return a LENGTH of 0 to indicate the register was not updated 204 but no error has occurred. */ 205 206 int sim_store_register (SIM_DESC sd, int regno, unsigned char *buf, int length); 207 208 209 /* Print whatever statistics the simulator has collected. 210 211 VERBOSE is currently unused and must always be zero. */ 212 213 void sim_info (SIM_DESC sd, int verbose); 214 215 216 /* Return a memory map in XML format. 217 218 The caller must free the returned string. 219 220 For details on the format, see GDB's Memory Map Format documentation. */ 221 222 char *sim_memory_map (SIM_DESC sd); 223 224 225 /* Run (or resume) the simulated program. 226 227 STEP, when non-zero indicates that only a single simulator cycle 228 should be emulated. 229 230 SIGGNAL, if non-zero is a (HOST) SIGRC value indicating the type of 231 event (hardware interrupt, signal) to be delivered to the simulated 232 program. 233 234 Hardware simulator: If the SIGRC value returned by 235 sim_stop_reason() is passed back to the simulator via SIGGNAL then 236 the hardware simulator shall correctly deliver the hardware event 237 indicated by that signal. If a value of zero is passed in then the 238 simulation will continue as if there were no outstanding signal. 239 The effect of any other SIGGNAL value is is implementation 240 dependant. 241 242 Process simulator: If SIGRC is non-zero then the corresponding 243 signal is delivered to the simulated program and execution is then 244 continued. A zero SIGRC value indicates that the program should 245 continue as normal. */ 246 247 void sim_resume (SIM_DESC sd, int step, int siggnal); 248 249 250 /* Asynchronous request to stop the simulation. 251 A nonzero return indicates that the simulator is able to handle 252 the request */ 253 254 int sim_stop (SIM_DESC sd); 255 256 257 /* Fetch the REASON why the program stopped. 258 259 SIM_EXITED: The program has terminated. SIGRC indicates the target 260 dependant exit status. 261 262 SIM_STOPPED: The program has stopped. SIGRC uses the host's signal 263 numbering as a way of identifying the reaon: program interrupted by 264 user via a sim_stop request (SIGINT); a breakpoint instruction 265 (SIGTRAP); a completed single step (SIGTRAP); an internal error 266 condition (SIGABRT); an illegal instruction (SIGILL); Access to an 267 undefined memory region (SIGSEGV); Mis-aligned memory access 268 (SIGBUS). For some signals information in addition to the signal 269 number may be retained by the simulator (e.g. offending address), 270 that information is not directly accessable via this interface. 271 272 SIM_SIGNALLED: The program has been terminated by a signal. The 273 simulator has encountered target code that causes the program 274 to exit with signal SIGRC. 275 276 SIM_RUNNING, SIM_POLLING: The return of one of these values 277 indicates a problem internal to the simulator. */ 278 279 enum sim_stop { sim_running, sim_polling, sim_exited, sim_stopped, sim_signalled }; 280 281 void sim_stop_reason (SIM_DESC sd, enum sim_stop *reason, int *sigrc); 282 283 284 /* Passthru for other commands that the simulator might support. 285 Simulators should be prepared to deal with any combination of NULL 286 or empty CMD. */ 287 288 void sim_do_command (SIM_DESC sd, const char *cmd); 289 290 /* Complete a command based on the available sim commands. Returns an 291 array of possible matches. */ 292 293 char **sim_complete_command (SIM_DESC sd, const char *text, const char *word); 294 295 #ifdef __cplusplus 296 } 297 #endif 298 299 #endif /* !defined (SIM_SIM_H) */ 300