1 /* Interface definition for configurable Xtensa ISA support. 2 Copyright 2003, 2004, 2005 Free Software Foundation, Inc. 3 4 This file is part of BFD, the Binary File Descriptor library. 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 2 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, write to the Free Software 18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ 19 20 #ifndef XTENSA_LIBISA_H 21 #define XTENSA_LIBISA_H 22 23 #ifdef __cplusplus 24 extern "C" { 25 #endif 26 27 /* Use the statically-linked version for the GNU tools. */ 28 #define STATIC_LIBISA 1 29 30 /* Version number: This is intended to help support code that works with 31 versions of this library from multiple Xtensa releases. */ 32 33 #define XTENSA_ISA_VERSION 7000 34 35 #ifndef uint32 36 #define uint32 unsigned int 37 #endif 38 39 /* This file defines the interface to the Xtensa ISA library. This 40 library contains most of the ISA-specific information for a 41 particular Xtensa processor. For example, the set of valid 42 instructions, their opcode encodings and operand fields are all 43 included here. 44 45 This interface basically defines a number of abstract data types. 46 47 . an instruction buffer - for holding the raw instruction bits 48 . ISA info - information about the ISA as a whole 49 . instruction formats - instruction size and slot structure 50 . opcodes - information about individual instructions 51 . operands - information about register and immediate instruction operands 52 . stateOperands - information about processor state instruction operands 53 . interfaceOperands - information about interface instruction operands 54 . register files - register file information 55 . processor states - internal processor state information 56 . system registers - "special registers" and "user registers" 57 . interfaces - TIE interfaces that are external to the processor 58 . functional units - TIE shared functions 59 60 The interface defines a set of functions to access each data type. 61 With the exception of the instruction buffer, the internal 62 representations of the data structures are hidden. All accesses must 63 be made through the functions defined here. */ 64 65 typedef struct xtensa_isa_opaque { int unused; } *xtensa_isa; 66 67 68 /* Most of the Xtensa ISA entities (e.g., opcodes, regfiles, etc.) are 69 represented here using sequential integers beginning with 0. The 70 specific values are only fixed for a particular instantiation of an 71 xtensa_isa structure, so these values should only be used 72 internally. */ 73 74 typedef int xtensa_opcode; 75 typedef int xtensa_format; 76 typedef int xtensa_regfile; 77 typedef int xtensa_state; 78 typedef int xtensa_sysreg; 79 typedef int xtensa_interface; 80 typedef int xtensa_funcUnit; 81 82 83 /* Define a unique value for undefined items. */ 84 85 #define XTENSA_UNDEFINED -1 86 87 88 /* Overview of using this interface to decode/encode instructions: 89 90 Each Xtensa instruction is associated with a particular instruction 91 format, where the format defines a fixed number of slots for 92 operations. The formats for the core Xtensa ISA have only one slot, 93 but FLIX instructions may have multiple slots. Within each slot, 94 there is a single opcode and some number of associated operands. 95 96 The encoding and decoding functions operate on instruction buffers, 97 not on the raw bytes of the instructions. The same instruction 98 buffer data structure is used for both entire instructions and 99 individual slots in those instructions -- the contents of a slot need 100 to be extracted from or inserted into the buffer for the instruction 101 as a whole. 102 103 Decoding an instruction involves first finding the format, which 104 identifies the number of slots, and then decoding each slot 105 separately. A slot is decoded by finding the opcode and then using 106 the opcode to determine how many operands there are. For example: 107 108 xtensa_insnbuf_from_chars 109 xtensa_format_decode 110 for each slot { 111 xtensa_format_get_slot 112 xtensa_opcode_decode 113 for each operand { 114 xtensa_operand_get_field 115 xtensa_operand_decode 116 } 117 } 118 119 Encoding an instruction is roughly the same procedure in reverse: 120 121 xtensa_format_encode 122 for each slot { 123 xtensa_opcode_encode 124 for each operand { 125 xtensa_operand_encode 126 xtensa_operand_set_field 127 } 128 xtensa_format_set_slot 129 } 130 xtensa_insnbuf_to_chars 131 */ 132 133 134 /* Error handling. */ 135 136 /* Error codes. The code for the most recent error condition can be 137 retrieved with the "errno" function. For any result other than 138 xtensa_isa_ok, an error message containing additional information 139 about the problem can be retrieved using the "error_msg" function. 140 The error messages are stored in an internal buffer, which should not 141 should be freed and may be overwritten by subsequent operations. */ 142 143 typedef enum xtensa_isa_status_enum 144 { 145 xtensa_isa_ok = 0, 146 xtensa_isa_bad_format, 147 xtensa_isa_bad_slot, 148 xtensa_isa_bad_opcode, 149 xtensa_isa_bad_operand, 150 xtensa_isa_bad_field, 151 xtensa_isa_bad_iclass, 152 xtensa_isa_bad_regfile, 153 xtensa_isa_bad_sysreg, 154 xtensa_isa_bad_state, 155 xtensa_isa_bad_interface, 156 xtensa_isa_bad_funcUnit, 157 xtensa_isa_wrong_slot, 158 xtensa_isa_no_field, 159 xtensa_isa_out_of_memory, 160 xtensa_isa_buffer_overflow, 161 xtensa_isa_internal_error, 162 xtensa_isa_bad_value 163 } xtensa_isa_status; 164 165 extern xtensa_isa_status 166 xtensa_isa_errno (xtensa_isa isa); 167 168 extern char * 169 xtensa_isa_error_msg (xtensa_isa isa); 170 171 172 173 /* Instruction buffers. */ 174 175 typedef uint32 xtensa_insnbuf_word; 176 typedef xtensa_insnbuf_word *xtensa_insnbuf; 177 178 179 /* Get the size in "insnbuf_words" of the xtensa_insnbuf array. */ 180 181 extern int 182 xtensa_insnbuf_size (xtensa_isa isa); 183 184 185 /* Allocate an xtensa_insnbuf of the right size. */ 186 187 extern xtensa_insnbuf 188 xtensa_insnbuf_alloc (xtensa_isa isa); 189 190 191 /* Release an xtensa_insnbuf. */ 192 193 extern void 194 xtensa_insnbuf_free (xtensa_isa isa, xtensa_insnbuf buf); 195 196 197 /* Conversion between raw memory (char arrays) and our internal 198 instruction representation. This is complicated by the Xtensa ISA's 199 variable instruction lengths. When converting to chars, the buffer 200 must contain a valid instruction so we know how many bytes to copy; 201 thus, the "to_chars" function returns the number of bytes copied or 202 XTENSA_UNDEFINED on error. The "from_chars" function first reads the 203 minimal number of bytes required to decode the instruction length and 204 then proceeds to copy the entire instruction into the buffer; if the 205 memory does not contain a valid instruction, it copies the maximum 206 number of bytes required for the longest Xtensa instruction. The 207 "num_chars" argument may be used to limit the number of bytes that 208 can be read or written. Otherwise, if "num_chars" is zero, the 209 functions may read or write past the end of the code. */ 210 211 extern int 212 xtensa_insnbuf_to_chars (xtensa_isa isa, const xtensa_insnbuf insn, 213 unsigned char *cp, int num_chars); 214 215 extern void 216 xtensa_insnbuf_from_chars (xtensa_isa isa, xtensa_insnbuf insn, 217 const unsigned char *cp, int num_chars); 218 219 220 221 /* ISA information. */ 222 223 /* Initialize the ISA information. */ 224 225 extern xtensa_isa 226 xtensa_isa_init (xtensa_isa_status *errno_p, char **error_msg_p); 227 228 229 /* Deallocate an xtensa_isa structure. */ 230 231 extern void 232 xtensa_isa_free (xtensa_isa isa); 233 234 235 /* Get the maximum instruction size in bytes. */ 236 237 extern int 238 xtensa_isa_maxlength (xtensa_isa isa); 239 240 241 /* Decode the length in bytes of an instruction in raw memory (not an 242 insnbuf). This function reads only the minimal number of bytes 243 required to decode the instruction length. Returns 244 XTENSA_UNDEFINED on error. */ 245 246 extern int 247 xtensa_isa_length_from_chars (xtensa_isa isa, const unsigned char *cp); 248 249 250 /* Get the number of stages in the processor's pipeline. The pipeline 251 stage values returned by other functions in this library will range 252 from 0 to N-1, where N is the value returned by this function. 253 Note that the stage numbers used here may not correspond to the 254 actual processor hardware, e.g., the hardware may have additional 255 stages before stage 0. Returns XTENSA_UNDEFINED on error. */ 256 257 extern int 258 xtensa_isa_num_pipe_stages (xtensa_isa isa); 259 260 261 /* Get the number of various entities that are defined for this processor. */ 262 263 extern int 264 xtensa_isa_num_formats (xtensa_isa isa); 265 266 extern int 267 xtensa_isa_num_opcodes (xtensa_isa isa); 268 269 extern int 270 xtensa_isa_num_regfiles (xtensa_isa isa); 271 272 extern int 273 xtensa_isa_num_states (xtensa_isa isa); 274 275 extern int 276 xtensa_isa_num_sysregs (xtensa_isa isa); 277 278 extern int 279 xtensa_isa_num_interfaces (xtensa_isa isa); 280 281 extern int 282 xtensa_isa_num_funcUnits (xtensa_isa isa); 283 284 285 286 /* Instruction formats. */ 287 288 /* Get the name of a format. Returns null on error. */ 289 290 extern const char * 291 xtensa_format_name (xtensa_isa isa, xtensa_format fmt); 292 293 294 /* Given a format name, return the format number. Returns 295 XTENSA_UNDEFINED if the name is not a valid format. */ 296 297 extern xtensa_format 298 xtensa_format_lookup (xtensa_isa isa, const char *fmtname); 299 300 301 /* Decode the instruction format from a binary instruction buffer. 302 Returns XTENSA_UNDEFINED if the format is not recognized. */ 303 304 extern xtensa_format 305 xtensa_format_decode (xtensa_isa isa, const xtensa_insnbuf insn); 306 307 308 /* Set the instruction format field(s) in a binary instruction buffer. 309 All the other fields are set to zero. Returns non-zero on error. */ 310 311 extern int 312 xtensa_format_encode (xtensa_isa isa, xtensa_format fmt, xtensa_insnbuf insn); 313 314 315 /* Find the length (in bytes) of an instruction. Returns 316 XTENSA_UNDEFINED on error. */ 317 318 extern int 319 xtensa_format_length (xtensa_isa isa, xtensa_format fmt); 320 321 322 /* Get the number of slots in an instruction. Returns XTENSA_UNDEFINED 323 on error. */ 324 325 extern int 326 xtensa_format_num_slots (xtensa_isa isa, xtensa_format fmt); 327 328 329 /* Get the opcode for a no-op in a particular slot. 330 Returns XTENSA_UNDEFINED on error. */ 331 332 extern xtensa_opcode 333 xtensa_format_slot_nop_opcode (xtensa_isa isa, xtensa_format fmt, int slot); 334 335 336 /* Get the bits for a specified slot out of an insnbuf for the 337 instruction as a whole and put them into an insnbuf for that one 338 slot, and do the opposite to set a slot. Return non-zero on error. */ 339 340 extern int 341 xtensa_format_get_slot (xtensa_isa isa, xtensa_format fmt, int slot, 342 const xtensa_insnbuf insn, xtensa_insnbuf slotbuf); 343 344 extern int 345 xtensa_format_set_slot (xtensa_isa isa, xtensa_format fmt, int slot, 346 xtensa_insnbuf insn, const xtensa_insnbuf slotbuf); 347 348 349 350 /* Opcode information. */ 351 352 /* Translate a mnemonic name to an opcode. Returns XTENSA_UNDEFINED if 353 the name is not a valid opcode mnemonic. */ 354 355 extern xtensa_opcode 356 xtensa_opcode_lookup (xtensa_isa isa, const char *opname); 357 358 359 /* Decode the opcode for one instruction slot from a binary instruction 360 buffer. Returns the opcode or XTENSA_UNDEFINED if the opcode is 361 illegal. */ 362 363 extern xtensa_opcode 364 xtensa_opcode_decode (xtensa_isa isa, xtensa_format fmt, int slot, 365 const xtensa_insnbuf slotbuf); 366 367 368 /* Set the opcode field(s) for an instruction slot. All other fields 369 in the slot are set to zero. Returns non-zero if the opcode cannot 370 be encoded. */ 371 372 extern int 373 xtensa_opcode_encode (xtensa_isa isa, xtensa_format fmt, int slot, 374 xtensa_insnbuf slotbuf, xtensa_opcode opc); 375 376 377 /* Get the mnemonic name for an opcode. Returns null on error. */ 378 379 extern const char * 380 xtensa_opcode_name (xtensa_isa isa, xtensa_opcode opc); 381 382 383 /* Check various properties of opcodes. These functions return 0 if 384 the condition is false, 1 if the condition is true, and 385 XTENSA_UNDEFINED on error. The instructions are classified as 386 follows: 387 388 branch: conditional branch; may fall through to next instruction (B*) 389 jump: unconditional branch (J, JX, RET*, RF*) 390 loop: zero-overhead loop (LOOP*) 391 call: unconditional call; control returns to next instruction (CALL*) 392 393 For the opcodes that affect control flow in some way, the branch 394 target may be specified by an immediate operand or it may be an 395 address stored in a register. You can distinguish these by 396 checking if the instruction has a PC-relative immediate 397 operand. */ 398 399 extern int 400 xtensa_opcode_is_branch (xtensa_isa isa, xtensa_opcode opc); 401 402 extern int 403 xtensa_opcode_is_jump (xtensa_isa isa, xtensa_opcode opc); 404 405 extern int 406 xtensa_opcode_is_loop (xtensa_isa isa, xtensa_opcode opc); 407 408 extern int 409 xtensa_opcode_is_call (xtensa_isa isa, xtensa_opcode opc); 410 411 412 /* Find the number of ordinary operands, state operands, and interface 413 operands for an instruction. These return XTENSA_UNDEFINED on 414 error. */ 415 416 extern int 417 xtensa_opcode_num_operands (xtensa_isa isa, xtensa_opcode opc); 418 419 extern int 420 xtensa_opcode_num_stateOperands (xtensa_isa isa, xtensa_opcode opc); 421 422 extern int 423 xtensa_opcode_num_interfaceOperands (xtensa_isa isa, xtensa_opcode opc); 424 425 426 /* Get functional unit usage requirements for an opcode. Each "use" 427 is identified by a <functional unit, pipeline stage> pair. The 428 "num_funcUnit_uses" function returns the number of these "uses" or 429 XTENSA_UNDEFINED on error. The "funcUnit_use" function returns 430 a pointer to a "use" pair or null on error. */ 431 432 typedef struct xtensa_funcUnit_use_struct 433 { 434 xtensa_funcUnit unit; 435 int stage; 436 } xtensa_funcUnit_use; 437 438 extern int 439 xtensa_opcode_num_funcUnit_uses (xtensa_isa isa, xtensa_opcode opc); 440 441 extern xtensa_funcUnit_use * 442 xtensa_opcode_funcUnit_use (xtensa_isa isa, xtensa_opcode opc, int u); 443 444 445 446 /* Operand information. */ 447 448 /* Get the name of an operand. Returns null on error. */ 449 450 extern const char * 451 xtensa_operand_name (xtensa_isa isa, xtensa_opcode opc, int opnd); 452 453 454 /* Some operands are "invisible", i.e., not explicitly specified in 455 assembly language. When assembling an instruction, you need not set 456 the values of invisible operands, since they are either hardwired or 457 derived from other field values. The values of invisible operands 458 can be examined in the same way as other operands, but remember that 459 an invisible operand may get its value from another visible one, so 460 the entire instruction must be available before examining the 461 invisible operand values. This function returns 1 if an operand is 462 visible, 0 if it is invisible, or XTENSA_UNDEFINED on error. Note 463 that whether an operand is visible is orthogonal to whether it is 464 "implicit", i.e., whether it is encoded in a field in the 465 instruction. */ 466 467 extern int 468 xtensa_operand_is_visible (xtensa_isa isa, xtensa_opcode opc, int opnd); 469 470 471 /* Check if an operand is an input ('i'), output ('o'), or inout ('m') 472 operand. Note: The output operand of a conditional assignment 473 (e.g., movnez) appears here as an inout ('m') even if it is declared 474 in the TIE code as an output ('o'); this allows the compiler to 475 properly handle register allocation for conditional assignments. 476 Returns 0 on error. */ 477 478 extern char 479 xtensa_operand_inout (xtensa_isa isa, xtensa_opcode opc, int opnd); 480 481 482 /* Get and set the raw (encoded) value of the field for the specified 483 operand. The "set" function does not check if the value fits in the 484 field; that is done by the "encode" function below. Both of these 485 functions return non-zero on error, e.g., if the field is not defined 486 for the specified slot. */ 487 488 extern int 489 xtensa_operand_get_field (xtensa_isa isa, xtensa_opcode opc, int opnd, 490 xtensa_format fmt, int slot, 491 const xtensa_insnbuf slotbuf, uint32 *valp); 492 493 extern int 494 xtensa_operand_set_field (xtensa_isa isa, xtensa_opcode opc, int opnd, 495 xtensa_format fmt, int slot, 496 xtensa_insnbuf slotbuf, uint32 val); 497 498 499 /* Encode and decode operands. The raw bits in the operand field may 500 be encoded in a variety of different ways. These functions hide 501 the details of that encoding. The result values are returned through 502 the argument pointer. The return value is non-zero on error. */ 503 504 extern int 505 xtensa_operand_encode (xtensa_isa isa, xtensa_opcode opc, int opnd, 506 uint32 *valp); 507 508 extern int 509 xtensa_operand_decode (xtensa_isa isa, xtensa_opcode opc, int opnd, 510 uint32 *valp); 511 512 513 /* An operand may be either a register operand or an immediate of some 514 sort (e.g., PC-relative or not). The "is_register" function returns 515 0 if the operand is an immediate, 1 if it is a register, and 516 XTENSA_UNDEFINED on error. The "regfile" function returns the 517 regfile for a register operand, or XTENSA_UNDEFINED on error. */ 518 519 extern int 520 xtensa_operand_is_register (xtensa_isa isa, xtensa_opcode opc, int opnd); 521 522 extern xtensa_regfile 523 xtensa_operand_regfile (xtensa_isa isa, xtensa_opcode opc, int opnd); 524 525 526 /* Register operands may span multiple consecutive registers, e.g., a 527 64-bit data type may occupy two 32-bit registers. Only the first 528 register is encoded in the operand field. This function specifies 529 the number of consecutive registers occupied by this operand. For 530 non-register operands, the return value is undefined. Returns 531 XTENSA_UNDEFINED on error. */ 532 533 extern int 534 xtensa_operand_num_regs (xtensa_isa isa, xtensa_opcode opc, int opnd); 535 536 537 /* Some register operands do not completely identify the register being 538 accessed. For example, the operand value may be added to an internal 539 state value. By definition, this implies that the corresponding 540 regfile is not allocatable. Unknown registers should generally be 541 treated with worst-case assumptions. The function returns 0 if the 542 register value is unknown, 1 if known, and XTENSA_UNDEFINED on 543 error. */ 544 545 extern int 546 xtensa_operand_is_known_reg (xtensa_isa isa, xtensa_opcode opc, int opnd); 547 548 549 /* Check if an immediate operand is PC-relative. Returns 0 for register 550 operands and non-PC-relative immediates, 1 for PC-relative 551 immediates, and XTENSA_UNDEFINED on error. */ 552 553 extern int 554 xtensa_operand_is_PCrelative (xtensa_isa isa, xtensa_opcode opc, int opnd); 555 556 557 /* For PC-relative offset operands, the interpretation of the offset may 558 vary between opcodes, e.g., is it relative to the current PC or that 559 of the next instruction? The following functions are defined to 560 perform PC-relative relocations and to undo them (as in the 561 disassembler). The "do_reloc" function takes the desired address 562 value and the PC of the current instruction and sets the value to the 563 corresponding PC-relative offset (which can then be encoded and 564 stored into the operand field). The "undo_reloc" function takes the 565 unencoded offset value and the current PC and sets the value to the 566 appropriate address. The return values are non-zero on error. Note 567 that these functions do not replace the encode/decode functions; the 568 operands must be encoded/decoded separately and the encode functions 569 are responsible for detecting invalid operand values. */ 570 571 extern int 572 xtensa_operand_do_reloc (xtensa_isa isa, xtensa_opcode opc, int opnd, 573 uint32 *valp, uint32 pc); 574 575 extern int 576 xtensa_operand_undo_reloc (xtensa_isa isa, xtensa_opcode opc, int opnd, 577 uint32 *valp, uint32 pc); 578 579 580 581 /* State Operands. */ 582 583 /* Get the state accessed by a state operand. Returns XTENSA_UNDEFINED 584 on error. */ 585 586 extern xtensa_state 587 xtensa_stateOperand_state (xtensa_isa isa, xtensa_opcode opc, int stOp); 588 589 590 /* Check if a state operand is an input ('i'), output ('o'), or inout 591 ('m') operand. Returns 0 on error. */ 592 593 extern char 594 xtensa_stateOperand_inout (xtensa_isa isa, xtensa_opcode opc, int stOp); 595 596 597 598 /* Interface Operands. */ 599 600 /* Get the external interface accessed by an interface operand. 601 Returns XTENSA_UNDEFINED on error. */ 602 603 extern xtensa_interface 604 xtensa_interfaceOperand_interface (xtensa_isa isa, xtensa_opcode opc, 605 int ifOp); 606 607 608 609 /* Register Files. */ 610 611 /* Regfiles include both "real" regfiles and "views", where a view 612 allows a group of adjacent registers in a real "parent" regfile to be 613 viewed as a single register. A regfile view has all the same 614 properties as its parent except for its (long) name, bit width, number 615 of entries, and default ctype. You can use the parent function to 616 distinguish these two classes. */ 617 618 /* Look up a regfile by either its name or its abbreviated "short name". 619 Returns XTENSA_UNDEFINED on error. The "lookup_shortname" function 620 ignores "view" regfiles since they always have the same shortname as 621 their parents. */ 622 623 extern xtensa_regfile 624 xtensa_regfile_lookup (xtensa_isa isa, const char *name); 625 626 extern xtensa_regfile 627 xtensa_regfile_lookup_shortname (xtensa_isa isa, const char *shortname); 628 629 630 /* Get the name or abbreviated "short name" of a regfile. 631 Returns null on error. */ 632 633 extern const char * 634 xtensa_regfile_name (xtensa_isa isa, xtensa_regfile rf); 635 636 extern const char * 637 xtensa_regfile_shortname (xtensa_isa isa, xtensa_regfile rf); 638 639 640 /* Get the parent regfile of a "view" regfile. If the regfile is not a 641 view, the result is the same as the input parameter. Returns 642 XTENSA_UNDEFINED on error. */ 643 644 extern xtensa_regfile 645 xtensa_regfile_view_parent (xtensa_isa isa, xtensa_regfile rf); 646 647 648 /* Get the bit width of a regfile or regfile view. 649 Returns XTENSA_UNDEFINED on error. */ 650 651 extern int 652 xtensa_regfile_num_bits (xtensa_isa isa, xtensa_regfile rf); 653 654 655 /* Get the number of regfile entries. Returns XTENSA_UNDEFINED on 656 error. */ 657 658 extern int 659 xtensa_regfile_num_entries (xtensa_isa isa, xtensa_regfile rf); 660 661 662 663 /* Processor States. */ 664 665 /* Look up a state by name. Returns XTENSA_UNDEFINED on error. */ 666 667 extern xtensa_state 668 xtensa_state_lookup (xtensa_isa isa, const char *name); 669 670 671 /* Get the name for a processor state. Returns null on error. */ 672 673 extern const char * 674 xtensa_state_name (xtensa_isa isa, xtensa_state st); 675 676 677 /* Get the bit width for a processor state. 678 Returns XTENSA_UNDEFINED on error. */ 679 680 extern int 681 xtensa_state_num_bits (xtensa_isa isa, xtensa_state st); 682 683 684 /* Check if a state is exported from the processor core. Returns 0 if 685 the condition is false, 1 if the condition is true, and 686 XTENSA_UNDEFINED on error. */ 687 688 extern int 689 xtensa_state_is_exported (xtensa_isa isa, xtensa_state st); 690 691 692 693 /* Sysregs ("special registers" and "user registers"). */ 694 695 /* Look up a register by its number and whether it is a "user register" 696 or a "special register". Returns XTENSA_UNDEFINED if the sysreg does 697 not exist. */ 698 699 extern xtensa_sysreg 700 xtensa_sysreg_lookup (xtensa_isa isa, int num, int is_user); 701 702 703 /* Check if there exists a sysreg with a given name. 704 If not, this function returns XTENSA_UNDEFINED. */ 705 706 extern xtensa_sysreg 707 xtensa_sysreg_lookup_name (xtensa_isa isa, const char *name); 708 709 710 /* Get the name of a sysreg. Returns null on error. */ 711 712 extern const char * 713 xtensa_sysreg_name (xtensa_isa isa, xtensa_sysreg sysreg); 714 715 716 /* Get the register number. Returns XTENSA_UNDEFINED on error. */ 717 718 extern int 719 xtensa_sysreg_number (xtensa_isa isa, xtensa_sysreg sysreg); 720 721 722 /* Check if a sysreg is a "special register" or a "user register". 723 Returns 0 for special registers, 1 for user registers and 724 XTENSA_UNDEFINED on error. */ 725 726 extern int 727 xtensa_sysreg_is_user (xtensa_isa isa, xtensa_sysreg sysreg); 728 729 730 731 /* Interfaces. */ 732 733 /* Find an interface by name. The return value is XTENSA_UNDEFINED if 734 the specified interface is not found. */ 735 736 extern xtensa_interface 737 xtensa_interface_lookup (xtensa_isa isa, const char *ifname); 738 739 740 /* Get the name of an interface. Returns null on error. */ 741 742 extern const char * 743 xtensa_interface_name (xtensa_isa isa, xtensa_interface intf); 744 745 746 /* Get the bit width for an interface. 747 Returns XTENSA_UNDEFINED on error. */ 748 749 extern int 750 xtensa_interface_num_bits (xtensa_isa isa, xtensa_interface intf); 751 752 753 /* Check if an interface is an input ('i') or output ('o') with respect 754 to the Xtensa processor core. Returns 0 on error. */ 755 756 extern char 757 xtensa_interface_inout (xtensa_isa isa, xtensa_interface intf); 758 759 760 /* Check if accessing an interface has potential side effects. 761 Currently "data" interfaces have side effects and "control" 762 interfaces do not. Returns 1 if there are side effects, 0 if not, 763 and XTENSA_UNDEFINED on error. */ 764 765 extern int 766 xtensa_interface_has_side_effect (xtensa_isa isa, xtensa_interface intf); 767 768 769 /* Some interfaces may be related such that accessing one interface 770 has side effects on a set of related interfaces. The interfaces 771 are partitioned into equivalence classes of related interfaces, and 772 each class is assigned a unique identifier number. This function 773 returns the class identifier for an interface, or XTENSA_UNDEFINED 774 on error. These identifiers can be compared to determine if two 775 interfaces are related; the specific values of the identifiers have 776 no particular meaning otherwise. */ 777 778 extern int 779 xtensa_interface_class_id (xtensa_isa isa, xtensa_interface intf); 780 781 782 783 /* Functional Units. */ 784 785 /* Find a functional unit by name. The return value is XTENSA_UNDEFINED if 786 the specified unit is not found. */ 787 788 extern xtensa_funcUnit 789 xtensa_funcUnit_lookup (xtensa_isa isa, const char *fname); 790 791 792 /* Get the name of a functional unit. Returns null on error. */ 793 794 extern const char * 795 xtensa_funcUnit_name (xtensa_isa isa, xtensa_funcUnit fun); 796 797 798 /* Functional units may be replicated. See how many instances of a 799 particular function unit exist. Returns XTENSA_UNDEFINED on error. */ 800 801 extern int 802 xtensa_funcUnit_num_copies (xtensa_isa isa, xtensa_funcUnit fun); 803 804 805 #ifdef __cplusplus 806 } 807 #endif 808 #endif /* XTENSA_LIBISA_H */ 809