1 /* Interface definition for configurable Xtensa ISA support.
2  *
3  * Copyright (c) 2001-2013 Tensilica Inc.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining
6  * a copy of this software and associated documentation files (the
7  * "Software"), to deal in the Software without restriction, including
8  * without limitation the rights to use, copy, modify, merge, publish,
9  * distribute, sublicense, and/or sell copies of the Software, and to
10  * permit persons to whom the Software is furnished to do so, subject to
11  * the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included
14  * in all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
19  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
20  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
21  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
22  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23  */
24 
25 #ifndef HW_XTENSA_XTENSA_ISA_H
26 #define HW_XTENSA_XTENSA_ISA_H
27 
28 #ifdef __cplusplus
29 extern "C" {
30 #endif
31 
32 /*
33  * Version number: This is intended to help support code that works with
34  * versions of this library from multiple Xtensa releases.
35  */
36 
37 #define XTENSA_ISA_VERSION 7000
38 
39 /*
40  * This file defines the interface to the Xtensa ISA library. This
41  * library contains most of the ISA-specific information for a
42  * particular Xtensa processor. For example, the set of valid
43  * instructions, their opcode encodings and operand fields are all
44  * included here.
45  *
46  * This interface basically defines a number of abstract data types.
47  *
48  * . an instruction buffer - for holding the raw instruction bits
49  * . ISA info - information about the ISA as a whole
50  * . instruction formats - instruction size and slot structure
51  * . opcodes - information about individual instructions
52  * . operands - information about register and immediate instruction operands
53  * . stateOperands - information about processor state instruction operands
54  * . interfaceOperands - information about interface instruction operands
55  * . register files - register file information
56  * . processor states - internal processor state information
57  * . system registers - "special registers" and "user registers"
58  * . interfaces - TIE interfaces that are external to the processor
59  * . functional units - TIE shared functions
60  *
61  * The interface defines a set of functions to access each data type.
62  * With the exception of the instruction buffer, the internal
63  * representations of the data structures are hidden. All accesses must
64  * be made through the functions defined here.
65  */
66 
67 typedef struct xtensa_isa_opaque { int unused; } *xtensa_isa;
68 
69 
70 /*
71  * Most of the Xtensa ISA entities (e.g., opcodes, regfiles, etc.) are
72  * represented here using sequential integers beginning with 0. The
73  * specific values are only fixed for a particular instantiation of an
74  * xtensa_isa structure, so these values should only be used
75  * internally.
76  */
77 
78 typedef int xtensa_opcode;
79 typedef int xtensa_format;
80 typedef int xtensa_regfile;
81 typedef int xtensa_state;
82 typedef int xtensa_sysreg;
83 typedef int xtensa_interface;
84 typedef int xtensa_funcUnit;
85 
86 
87 /* Define a unique value for undefined items. */
88 
89 #define XTENSA_UNDEFINED -1
90 
91 
92 /*
93  * Overview of using this interface to decode/encode instructions:
94  *
95  * Each Xtensa instruction is associated with a particular instruction
96  * format, where the format defines a fixed number of slots for
97  * operations. The formats for the core Xtensa ISA have only one slot,
98  * but FLIX instructions may have multiple slots. Within each slot,
99  * there is a single opcode and some number of associated operands.
100  *
101  * The encoding and decoding functions operate on instruction buffers,
102  * not on the raw bytes of the instructions. The same instruction
103  * buffer data structure is used for both entire instructions and
104  * individual slots in those instructions -- the contents of a slot need
105  * to be extracted from or inserted into the buffer for the instruction
106  * as a whole.
107  *
108  * Decoding an instruction involves first finding the format, which
109  * identifies the number of slots, and then decoding each slot
110  * separately. A slot is decoded by finding the opcode and then using
111  * the opcode to determine how many operands there are. For example:
112  *
113  * xtensa_insnbuf_from_chars
114  * xtensa_format_decode
115  * for each slot {
116  *   xtensa_format_get_slot
117  *   xtensa_opcode_decode
118  *   for each operand {
119  *     xtensa_operand_get_field
120  *     xtensa_operand_decode
121  *   }
122  * }
123  *
124  * Encoding an instruction is roughly the same procedure in reverse:
125  *
126  * xtensa_format_encode
127  * for each slot {
128  *   xtensa_opcode_encode
129  *   for each operand {
130  *     xtensa_operand_encode
131  *     xtensa_operand_set_field
132  *   }
133  *   xtensa_format_set_slot
134  * }
135  * xtensa_insnbuf_to_chars
136  */
137 
138 
139 /* Error handling. */
140 
141 /*
142  * Error codes. The code for the most recent error condition can be
143  * retrieved with the "errno" function. For any result other than
144  * xtensa_isa_ok, an error message containing additional information
145  * about the problem can be retrieved using the "error_msg" function.
146  * The error messages are stored in an internal buffer, which should
147  * not be freed and may be overwritten by subsequent operations.
148  */
149 
150 typedef enum xtensa_isa_status_enum {
151     xtensa_isa_ok = 0,
152     xtensa_isa_bad_format,
153     xtensa_isa_bad_slot,
154     xtensa_isa_bad_opcode,
155     xtensa_isa_bad_operand,
156     xtensa_isa_bad_field,
157     xtensa_isa_bad_iclass,
158     xtensa_isa_bad_regfile,
159     xtensa_isa_bad_sysreg,
160     xtensa_isa_bad_state,
161     xtensa_isa_bad_interface,
162     xtensa_isa_bad_funcUnit,
163     xtensa_isa_wrong_slot,
164     xtensa_isa_no_field,
165     xtensa_isa_out_of_memory,
166     xtensa_isa_buffer_overflow,
167     xtensa_isa_internal_error,
168     xtensa_isa_bad_value
169 } xtensa_isa_status;
170 
171 xtensa_isa_status xtensa_isa_errno(xtensa_isa isa);
172 
173 char *xtensa_isa_error_msg(xtensa_isa isa);
174 
175 
176 
177 /* Instruction buffers. */
178 
179 typedef uint32_t xtensa_insnbuf_word;
180 typedef xtensa_insnbuf_word *xtensa_insnbuf;
181 
182 
183 /* Get the size in "insnbuf_words" of the xtensa_insnbuf array. */
184 
185 int xtensa_insnbuf_size(xtensa_isa isa);
186 
187 
188 /* Allocate an xtensa_insnbuf of the right size. */
189 
190 xtensa_insnbuf xtensa_insnbuf_alloc(xtensa_isa isa);
191 
192 
193 /* Release an xtensa_insnbuf. */
194 
195 void xtensa_insnbuf_free(xtensa_isa isa, xtensa_insnbuf buf);
196 
197 
198 /*
199  * Conversion between raw memory (char arrays) and our internal
200  * instruction representation. This is complicated by the Xtensa ISA's
201  * variable instruction lengths. When converting to chars, the buffer
202  * must contain a valid instruction so we know how many bytes to copy;
203  * thus, the "to_chars" function returns the number of bytes copied or
204  * XTENSA_UNDEFINED on error. The "from_chars" function first reads the
205  * minimal number of bytes required to decode the instruction length and
206  * then proceeds to copy the entire instruction into the buffer; if the
207  * memory does not contain a valid instruction, it copies the maximum
208  * number of bytes required for the longest Xtensa instruction. The
209  * "num_chars" argument may be used to limit the number of bytes that
210  * can be read or written. Otherwise, if "num_chars" is zero, the
211  * functions may read or write past the end of the code.
212  */
213 
214 int xtensa_insnbuf_to_chars(xtensa_isa isa, const xtensa_insnbuf insn,
215                             unsigned char *cp, int num_chars);
216 
217 void xtensa_insnbuf_from_chars(xtensa_isa isa, xtensa_insnbuf insn,
218                                const unsigned char *cp, int num_chars);
219 
220 
221 
222 /* ISA information. */
223 
224 /* Initialize the ISA information. */
225 
226 xtensa_isa xtensa_isa_init(void *xtensa_modules, xtensa_isa_status *errno_p,
227                            char **error_msg_p);
228 
229 
230 /* Deallocate an xtensa_isa structure. */
231 
232 void xtensa_isa_free(xtensa_isa isa);
233 
234 
235 /* Get the maximum instruction size in bytes. */
236 
237 int xtensa_isa_maxlength(xtensa_isa isa);
238 
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 
247 int xtensa_isa_length_from_chars(xtensa_isa isa, const unsigned char *cp);
248 
249 
250 /*
251  * Get the number of stages in the processor's pipeline. The pipeline
252  * stage values returned by other functions in this library will range
253  * from 0 to N-1, where N is the value returned by this function.
254  * Note that the stage numbers used here may not correspond to the
255  * actual processor hardware, e.g., the hardware may have additional
256  * stages before stage 0. Returns XTENSA_UNDEFINED on error.
257  */
258 
259 int xtensa_isa_num_pipe_stages(xtensa_isa isa);
260 
261 
262 /* Get the number of various entities that are defined for this processor. */
263 
264 int xtensa_isa_num_formats(xtensa_isa isa);
265 
266 int xtensa_isa_num_opcodes(xtensa_isa isa);
267 
268 int xtensa_isa_num_regfiles(xtensa_isa isa);
269 
270 int xtensa_isa_num_states(xtensa_isa isa);
271 
272 int xtensa_isa_num_sysregs(xtensa_isa isa);
273 
274 int xtensa_isa_num_interfaces(xtensa_isa isa);
275 
276 int xtensa_isa_num_funcUnits(xtensa_isa isa);
277 
278 
279 
280 /* Instruction formats. */
281 
282 /* Get the name of a format. Returns null on error. */
283 
284 const char *xtensa_format_name(xtensa_isa isa, xtensa_format fmt);
285 
286 
287 /*
288  * Given a format name, return the format number. Returns
289  * XTENSA_UNDEFINED if the name is not a valid format.
290  */
291 
292 xtensa_format xtensa_format_lookup(xtensa_isa isa, const char *fmtname);
293 
294 
295 /*
296  * Decode the instruction format from a binary instruction buffer.
297  * Returns XTENSA_UNDEFINED if the format is not recognized.
298  */
299 
300 xtensa_format xtensa_format_decode(xtensa_isa isa, const xtensa_insnbuf insn);
301 
302 
303 /*
304  * Set the instruction format field(s) in a binary instruction buffer.
305  * All the other fields are set to zero. Returns non-zero on error.
306  */
307 
308 int xtensa_format_encode(xtensa_isa isa, xtensa_format fmt,
309                          xtensa_insnbuf insn);
310 
311 
312 /*
313  * Find the length (in bytes) of an instruction. Returns
314  * XTENSA_UNDEFINED on error.
315  */
316 
317 int xtensa_format_length(xtensa_isa isa, xtensa_format fmt);
318 
319 
320 /*
321  * Get the number of slots in an instruction. Returns XTENSA_UNDEFINED
322  * on error.
323  */
324 
325 int xtensa_format_num_slots(xtensa_isa isa, xtensa_format fmt);
326 
327 
328 /*
329  * Get the opcode for a no-op in a particular slot.
330  * Returns XTENSA_UNDEFINED on error.
331  */
332 
333 xtensa_opcode xtensa_format_slot_nop_opcode(xtensa_isa isa, xtensa_format fmt,
334                                             int slot);
335 
336 
337 /*
338  * Get the bits for a specified slot out of an insnbuf for the
339  * instruction as a whole and put them into an insnbuf for that one
340  * slot, and do the opposite to set a slot. Return non-zero on error.
341  */
342 
343 int xtensa_format_get_slot(xtensa_isa isa, xtensa_format fmt, int slot,
344                            const xtensa_insnbuf insn, xtensa_insnbuf slotbuf);
345 
346 int xtensa_format_set_slot(xtensa_isa isa, xtensa_format fmt, int slot,
347                            xtensa_insnbuf insn, const xtensa_insnbuf slotbuf);
348 
349 
350 
351 /* Opcode information. */
352 
353 /*
354  * Translate a mnemonic name to an opcode. Returns XTENSA_UNDEFINED if
355  * the name is not a valid opcode mnemonic.
356  */
357 
358 xtensa_opcode xtensa_opcode_lookup(xtensa_isa isa, const char *opname);
359 
360 
361 /*
362  * Decode the opcode for one instruction slot from a binary instruction
363  * buffer. Returns the opcode or XTENSA_UNDEFINED if the opcode is
364  * illegal.
365  */
366 
367 xtensa_opcode xtensa_opcode_decode(xtensa_isa isa, xtensa_format fmt, int slot,
368                                    const xtensa_insnbuf slotbuf);
369 
370 
371 /*
372  * Set the opcode field(s) for an instruction slot. All other fields
373  * in the slot are set to zero. Returns non-zero if the opcode cannot
374  * be encoded.
375  */
376 
377 int xtensa_opcode_encode(xtensa_isa isa, xtensa_format fmt, int slot,
378                          xtensa_insnbuf slotbuf, xtensa_opcode opc);
379 
380 
381 /* Get the mnemonic name for an opcode. Returns null on error. */
382 
383 const char *xtensa_opcode_name(xtensa_isa isa, xtensa_opcode opc);
384 
385 
386 /* Check various properties of opcodes. These functions return 0 if
387  * the condition is false, 1 if the condition is true, and
388  * XTENSA_UNDEFINED on error. The instructions are classified as
389  * follows:
390  *
391  * branch: conditional branch; may fall through to next instruction (B*)
392  * jump: unconditional branch (J, JX, RET*, RF*)
393  * loop: zero-overhead loop (LOOP*)
394  * call: unconditional call; control returns to next instruction (CALL*)
395  *
396  * For the opcodes that affect control flow in some way, the branch
397  * target may be specified by an immediate operand or it may be an
398  * address stored in a register. You can distinguish these by
399  * checking if the instruction has a PC-relative immediate
400  * operand.
401  */
402 
403 int xtensa_opcode_is_branch(xtensa_isa isa, xtensa_opcode opc);
404 
405 int xtensa_opcode_is_jump(xtensa_isa isa, xtensa_opcode opc);
406 
407 int xtensa_opcode_is_loop(xtensa_isa isa, xtensa_opcode opc);
408 
409 int xtensa_opcode_is_call(xtensa_isa isa, xtensa_opcode opc);
410 
411 
412 /*
413  * Find the number of ordinary operands, state operands, and interface
414  * operands for an instruction. These return XTENSA_UNDEFINED on
415  * error.
416  */
417 
418 int xtensa_opcode_num_operands(xtensa_isa isa, xtensa_opcode opc);
419 
420 int xtensa_opcode_num_stateOperands(xtensa_isa isa, xtensa_opcode opc);
421 
422 int xtensa_opcode_num_interfaceOperands(xtensa_isa isa, xtensa_opcode opc);
423 
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 
433 typedef struct xtensa_funcUnit_use_struct {
434     xtensa_funcUnit unit;
435     int stage;
436 } xtensa_funcUnit_use;
437 
438 int xtensa_opcode_num_funcUnit_uses(xtensa_isa isa, xtensa_opcode opc);
439 
440 xtensa_funcUnit_use *xtensa_opcode_funcUnit_use(xtensa_isa isa,
441                                                 xtensa_opcode opc, int u);
442 
443 
444 
445 /* Operand information. */
446 
447 /* Get the name of an operand. Returns null on error. */
448 
449 const char *xtensa_operand_name(xtensa_isa isa, xtensa_opcode opc, int opnd);
450 
451 
452 /*
453  * Some operands are "invisible", i.e., not explicitly specified in
454  * assembly language. When assembling an instruction, you need not set
455  * the values of invisible operands, since they are either hardwired or
456  * derived from other field values. The values of invisible operands
457  * can be examined in the same way as other operands, but remember that
458  * an invisible operand may get its value from another visible one, so
459  * the entire instruction must be available before examining the
460  * invisible operand values. This function returns 1 if an operand is
461  * visible, 0 if it is invisible, or XTENSA_UNDEFINED on error. Note
462  * that whether an operand is visible is orthogonal to whether it is
463  * "implicit", i.e., whether it is encoded in a field in the
464  * instruction.
465  */
466 
467 int xtensa_operand_is_visible(xtensa_isa isa, xtensa_opcode opc, int opnd);
468 
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 
479 char xtensa_operand_inout(xtensa_isa isa, xtensa_opcode opc, int opnd);
480 
481 
482 /*
483  * Get and set the raw (encoded) value of the field for the specified
484  * operand. The "set" function does not check if the value fits in the
485  * field; that is done by the "encode" function below. Both of these
486  * functions return non-zero on error, e.g., if the field is not defined
487  * for the specified slot.
488  */
489 
490 int xtensa_operand_get_field(xtensa_isa isa, xtensa_opcode opc, int opnd,
491                              xtensa_format fmt, int slot,
492                              const xtensa_insnbuf slotbuf, uint32_t *valp);
493 
494 int xtensa_operand_set_field(xtensa_isa isa, xtensa_opcode opc, int opnd,
495                              xtensa_format fmt, int slot,
496                              xtensa_insnbuf slotbuf, uint32_t val);
497 
498 
499 /*
500  * Encode and decode operands. The raw bits in the operand field may
501  * be encoded in a variety of different ways. These functions hide
502  * the details of that encoding. The result values are returned through
503  * the argument pointer. The return value is non-zero on error.
504  */
505 
506 int xtensa_operand_encode(xtensa_isa isa, xtensa_opcode opc, int opnd,
507                           uint32_t *valp);
508 
509 int xtensa_operand_decode(xtensa_isa isa, xtensa_opcode opc, int opnd,
510                           uint32_t *valp);
511 
512 
513 /*
514  * An operand may be either a register operand or an immediate of some
515  * sort (e.g., PC-relative or not). The "is_register" function returns
516  * 0 if the operand is an immediate, 1 if it is a register, and
517  * XTENSA_UNDEFINED on error. The "regfile" function returns the
518  * regfile for a register operand, or XTENSA_UNDEFINED on error.
519  */
520 
521 int xtensa_operand_is_register(xtensa_isa isa, xtensa_opcode opc, int opnd);
522 
523 xtensa_regfile xtensa_operand_regfile(xtensa_isa isa, xtensa_opcode opc,
524                                       int opnd);
525 
526 
527 /*
528  * Register operands may span multiple consecutive registers, e.g., a
529  * 64-bit data type may occupy two 32-bit registers. Only the first
530  * register is encoded in the operand field. This function specifies
531  * the number of consecutive registers occupied by this operand. For
532  * non-register operands, the return value is undefined. Returns
533  * XTENSA_UNDEFINED on error.
534  */
535 
536 int xtensa_operand_num_regs(xtensa_isa isa, xtensa_opcode opc, int opnd);
537 
538 
539 /*
540  * Some register operands do not completely identify the register being
541  * accessed. For example, the operand value may be added to an internal
542  * state value. By definition, this implies that the corresponding
543  * regfile is not allocatable. Unknown registers should generally be
544  * treated with worst-case assumptions. The function returns 0 if the
545  * register value is unknown, 1 if known, and XTENSA_UNDEFINED on
546  * error.
547  */
548 
549 int xtensa_operand_is_known_reg(xtensa_isa isa, xtensa_opcode opc, int opnd);
550 
551 
552 /*
553  * Check if an immediate operand is PC-relative. Returns 0 for register
554  * operands and non-PC-relative immediates, 1 for PC-relative
555  * immediates, and XTENSA_UNDEFINED on error.
556  */
557 
558 int xtensa_operand_is_PCrelative(xtensa_isa isa, xtensa_opcode opc, int opnd);
559 
560 
561 /*
562  * For PC-relative offset operands, the interpretation of the offset may
563  * vary between opcodes, e.g., is it relative to the current PC or that
564  * of the next instruction?  The following functions are defined to
565  * perform PC-relative relocations and to undo them (as in the
566  * disassembler). The "do_reloc" function takes the desired address
567  * value and the PC of the current instruction and sets the value to the
568  * corresponding PC-relative offset (which can then be encoded and
569  * stored into the operand field). The "undo_reloc" function takes the
570  * unencoded offset value and the current PC and sets the value to the
571  * appropriate address. The return values are non-zero on error. Note
572  * that these functions do not replace the encode/decode functions; the
573  * operands must be encoded/decoded separately and the encode functions
574  * are responsible for detecting invalid operand values.
575  */
576 
577 int xtensa_operand_do_reloc(xtensa_isa isa, xtensa_opcode opc, int opnd,
578                             uint32_t *valp, uint32_t pc);
579 
580 int xtensa_operand_undo_reloc(xtensa_isa isa, xtensa_opcode opc, int opnd,
581                               uint32_t *valp, uint32_t pc);
582 
583 
584 
585 /* State Operands. */
586 
587 /*
588  * Get the state accessed by a state operand. Returns XTENSA_UNDEFINED
589  * on error.
590  */
591 
592 xtensa_state xtensa_stateOperand_state(xtensa_isa isa, xtensa_opcode opc,
593                                        int stOp);
594 
595 
596 /*
597  * Check if a state operand is an input ('i'), output ('o'), or inout
598  * ('m') operand. Returns 0 on error.
599  */
600 
601 char xtensa_stateOperand_inout(xtensa_isa isa, xtensa_opcode opc, int stOp);
602 
603 
604 
605 /* Interface Operands. */
606 
607 /*
608  * Get the external interface accessed by an interface operand.
609  * Returns XTENSA_UNDEFINED on error.
610  */
611 
612 xtensa_interface xtensa_interfaceOperand_interface(xtensa_isa isa,
613                                                    xtensa_opcode opc,
614                                                    int ifOp);
615 
616 
617 
618 /* Register Files. */
619 
620 /*
621  * Regfiles include both "real" regfiles and "views", where a view
622  * allows a group of adjacent registers in a real "parent" regfile to be
623  * viewed as a single register. A regfile view has all the same
624  * properties as its parent except for its (long) name, bit width, number
625  * of entries, and default ctype. You can use the parent function to
626  * distinguish these two classes.
627  */
628 
629 /*
630  * Look up a regfile by either its name or its abbreviated "short name".
631  * Returns XTENSA_UNDEFINED on error. The "lookup_shortname" function
632  * ignores "view" regfiles since they always have the same shortname as
633  * their parents.
634  */
635 
636 xtensa_regfile xtensa_regfile_lookup(xtensa_isa isa, const char *name);
637 
638 xtensa_regfile xtensa_regfile_lookup_shortname(xtensa_isa isa,
639                                                const char *shortname);
640 
641 
642 /*
643  * Get the name or abbreviated "short name" of a regfile.
644  * Returns null on error.
645  */
646 
647 const char *xtensa_regfile_name(xtensa_isa isa, xtensa_regfile rf);
648 
649 const char *xtensa_regfile_shortname(xtensa_isa isa, xtensa_regfile rf);
650 
651 
652 /*
653  * Get the parent regfile of a "view" regfile. If the regfile is not a
654  * view, the result is the same as the input parameter. Returns
655  * XTENSA_UNDEFINED on error.
656  */
657 
658 xtensa_regfile xtensa_regfile_view_parent(xtensa_isa isa, xtensa_regfile rf);
659 
660 
661 /*
662  * Get the bit width of a regfile or regfile view.
663  * Returns XTENSA_UNDEFINED on error.
664  */
665 
666 int xtensa_regfile_num_bits(xtensa_isa isa, xtensa_regfile rf);
667 
668 
669 /*
670  * Get the number of regfile entries. Returns XTENSA_UNDEFINED on
671  * error.
672  */
673 
674 int xtensa_regfile_num_entries(xtensa_isa isa, xtensa_regfile rf);
675 
676 
677 
678 /* Processor States. */
679 
680 /* Look up a state by name. Returns XTENSA_UNDEFINED on error. */
681 
682 xtensa_state xtensa_state_lookup(xtensa_isa isa, const char *name);
683 
684 
685 /* Get the name for a processor state. Returns null on error. */
686 
687 const char *xtensa_state_name(xtensa_isa isa, xtensa_state st);
688 
689 
690 /*
691  * Get the bit width for a processor state.
692  * Returns XTENSA_UNDEFINED on error.
693  */
694 
695 int xtensa_state_num_bits(xtensa_isa isa, xtensa_state st);
696 
697 
698 /*
699  * Check if a state is exported from the processor core. Returns 0 if
700  * the condition is false, 1 if the condition is true, and
701  * XTENSA_UNDEFINED on error.
702  */
703 
704 int xtensa_state_is_exported(xtensa_isa isa, xtensa_state st);
705 
706 
707 /*
708  * Check for a "shared_or" state. Returns 0 if the condition is false,
709  * 1 if the condition is true, and XTENSA_UNDEFINED on error.
710  */
711 
712 int xtensa_state_is_shared_or(xtensa_isa isa, xtensa_state st);
713 
714 
715 
716 /* Sysregs ("special registers" and "user registers"). */
717 
718 /*
719  * Look up a register by its number and whether it is a "user register"
720  * or a "special register". Returns XTENSA_UNDEFINED if the sysreg does
721  * not exist.
722  */
723 
724 xtensa_sysreg xtensa_sysreg_lookup(xtensa_isa isa, int num, int is_user);
725 
726 
727 /*
728  * Check if there exists a sysreg with a given name.
729  * If not, this function returns XTENSA_UNDEFINED.
730  */
731 
732 xtensa_sysreg xtensa_sysreg_lookup_name(xtensa_isa isa, const char *name);
733 
734 
735 /* Get the name of a sysreg. Returns null on error. */
736 
737 const char *xtensa_sysreg_name(xtensa_isa isa, xtensa_sysreg sysreg);
738 
739 
740 /* Get the register number. Returns XTENSA_UNDEFINED on error. */
741 
742 int xtensa_sysreg_number(xtensa_isa isa, xtensa_sysreg sysreg);
743 
744 
745 /*
746  * Check if a sysreg is a "special register" or a "user register".
747  * Returns 0 for special registers, 1 for user registers and
748  * XTENSA_UNDEFINED on error.
749  */
750 
751 int xtensa_sysreg_is_user(xtensa_isa isa, xtensa_sysreg sysreg);
752 
753 
754 
755 /* Interfaces. */
756 
757 /*
758  * Find an interface by name. The return value is XTENSA_UNDEFINED if
759  * the specified interface is not found.
760  */
761 
762 xtensa_interface xtensa_interface_lookup(xtensa_isa isa, const char *ifname);
763 
764 
765 /* Get the name of an interface. Returns null on error. */
766 
767 const char *xtensa_interface_name(xtensa_isa isa, xtensa_interface intf);
768 
769 
770 /*
771  * Get the bit width for an interface.
772  * Returns XTENSA_UNDEFINED on error.
773  */
774 
775 int xtensa_interface_num_bits(xtensa_isa isa, xtensa_interface intf);
776 
777 
778 /*
779  * Check if an interface is an input ('i') or output ('o') with respect
780  * to the Xtensa processor core. Returns 0 on error.
781  */
782 
783 char xtensa_interface_inout(xtensa_isa isa, xtensa_interface intf);
784 
785 
786 /*
787  * Check if accessing an interface has potential side effects.
788  * Currently "data" interfaces have side effects and "control"
789  * interfaces do not. Returns 1 if there are side effects, 0 if not,
790  * and XTENSA_UNDEFINED on error.
791  */
792 
793 int xtensa_interface_has_side_effect(xtensa_isa isa, xtensa_interface intf);
794 
795 
796 /*
797  * Some interfaces may be related such that accessing one interface
798  * has side effects on a set of related interfaces. The interfaces
799  * are partitioned into equivalence classes of related interfaces, and
800  * each class is assigned a unique identifier number. This function
801  * returns the class identifier for an interface, or XTENSA_UNDEFINED
802  * on error. These identifiers can be compared to determine if two
803  * interfaces are related; the specific values of the identifiers have
804  * no particular meaning otherwise.
805  */
806 
807 int xtensa_interface_class_id(xtensa_isa isa, xtensa_interface intf);
808 
809 
810 /* Functional Units. */
811 
812 /*
813  * Find a functional unit by name. The return value is XTENSA_UNDEFINED if
814  * the specified unit is not found.
815  */
816 
817 xtensa_funcUnit xtensa_funcUnit_lookup(xtensa_isa isa, const char *fname);
818 
819 
820 /* Get the name of a functional unit. Returns null on error. */
821 
822 const char *xtensa_funcUnit_name(xtensa_isa isa, xtensa_funcUnit fun);
823 
824 
825 /*
826  * Functional units may be replicated. See how many instances of a
827  * particular function unit exist. Returns XTENSA_UNDEFINED on error.
828  */
829 
830 int xtensa_funcUnit_num_copies(xtensa_isa isa, xtensa_funcUnit fun);
831 
832 
833 #ifdef __cplusplus
834 }
835 #endif
836 #endif /* HW_XTENSA_XTENSA_ISA_H */
837