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Diffstat (limited to 'include/hw/xtensa/xtensa-isa.h')
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diff --git a/include/hw/xtensa/xtensa-isa.h b/include/hw/xtensa/xtensa-isa.h new file mode 100644 index 0000000000..353f82ba25 --- /dev/null +++ b/include/hw/xtensa/xtensa-isa.h @@ -0,0 +1,838 @@ +/* Interface definition for configurable Xtensa ISA support. + * + * Copyright (c) 2001-2013 Tensilica Inc. + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. + * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY + * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, + * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE + * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + +#ifndef XTENSA_LIBISA_H +#define XTENSA_LIBISA_H + +#include <stdint.h> + +#ifdef __cplusplus +extern "C" { +#endif + +/* + * Version number: This is intended to help support code that works with + * versions of this library from multiple Xtensa releases. + */ + +#define XTENSA_ISA_VERSION 7000 + +/* + * This file defines the interface to the Xtensa ISA library. This + * library contains most of the ISA-specific information for a + * particular Xtensa processor. For example, the set of valid + * instructions, their opcode encodings and operand fields are all + * included here. + * + * This interface basically defines a number of abstract data types. + * + * . an instruction buffer - for holding the raw instruction bits + * . ISA info - information about the ISA as a whole + * . instruction formats - instruction size and slot structure + * . opcodes - information about individual instructions + * . operands - information about register and immediate instruction operands + * . stateOperands - information about processor state instruction operands + * . interfaceOperands - information about interface instruction operands + * . register files - register file information + * . processor states - internal processor state information + * . system registers - "special registers" and "user registers" + * . interfaces - TIE interfaces that are external to the processor + * . functional units - TIE shared functions + * + * The interface defines a set of functions to access each data type. + * With the exception of the instruction buffer, the internal + * representations of the data structures are hidden. All accesses must + * be made through the functions defined here. + */ + +typedef struct xtensa_isa_opaque { int unused; } *xtensa_isa; + + +/* + * Most of the Xtensa ISA entities (e.g., opcodes, regfiles, etc.) are + * represented here using sequential integers beginning with 0. The + * specific values are only fixed for a particular instantiation of an + * xtensa_isa structure, so these values should only be used + * internally. + */ + +typedef int xtensa_opcode; +typedef int xtensa_format; +typedef int xtensa_regfile; +typedef int xtensa_state; +typedef int xtensa_sysreg; +typedef int xtensa_interface; +typedef int xtensa_funcUnit; + + +/* Define a unique value for undefined items. */ + +#define XTENSA_UNDEFINED -1 + + +/* + * Overview of using this interface to decode/encode instructions: + * + * Each Xtensa instruction is associated with a particular instruction + * format, where the format defines a fixed number of slots for + * operations. The formats for the core Xtensa ISA have only one slot, + * but FLIX instructions may have multiple slots. Within each slot, + * there is a single opcode and some number of associated operands. + * + * The encoding and decoding functions operate on instruction buffers, + * not on the raw bytes of the instructions. The same instruction + * buffer data structure is used for both entire instructions and + * individual slots in those instructions -- the contents of a slot need + * to be extracted from or inserted into the buffer for the instruction + * as a whole. + * + * Decoding an instruction involves first finding the format, which + * identifies the number of slots, and then decoding each slot + * separately. A slot is decoded by finding the opcode and then using + * the opcode to determine how many operands there are. For example: + * + * xtensa_insnbuf_from_chars + * xtensa_format_decode + * for each slot { + * xtensa_format_get_slot + * xtensa_opcode_decode + * for each operand { + * xtensa_operand_get_field + * xtensa_operand_decode + * } + * } + * + * Encoding an instruction is roughly the same procedure in reverse: + * + * xtensa_format_encode + * for each slot { + * xtensa_opcode_encode + * for each operand { + * xtensa_operand_encode + * xtensa_operand_set_field + * } + * xtensa_format_set_slot + * } + * xtensa_insnbuf_to_chars + */ + + +/* Error handling. */ + +/* + * Error codes. The code for the most recent error condition can be + * retrieved with the "errno" function. For any result other than + * xtensa_isa_ok, an error message containing additional information + * about the problem can be retrieved using the "error_msg" function. + * The error messages are stored in an internal buffer, which should + * not be freed and may be overwritten by subsequent operations. + */ + +typedef enum xtensa_isa_status_enum { + xtensa_isa_ok = 0, + xtensa_isa_bad_format, + xtensa_isa_bad_slot, + xtensa_isa_bad_opcode, + xtensa_isa_bad_operand, + xtensa_isa_bad_field, + xtensa_isa_bad_iclass, + xtensa_isa_bad_regfile, + xtensa_isa_bad_sysreg, + xtensa_isa_bad_state, + xtensa_isa_bad_interface, + xtensa_isa_bad_funcUnit, + xtensa_isa_wrong_slot, + xtensa_isa_no_field, + xtensa_isa_out_of_memory, + xtensa_isa_buffer_overflow, + xtensa_isa_internal_error, + xtensa_isa_bad_value +} xtensa_isa_status; + +xtensa_isa_status xtensa_isa_errno(xtensa_isa isa); + +char *xtensa_isa_error_msg(xtensa_isa isa); + + + +/* Instruction buffers. */ + +typedef uint32_t xtensa_insnbuf_word; +typedef xtensa_insnbuf_word *xtensa_insnbuf; + + +/* Get the size in "insnbuf_words" of the xtensa_insnbuf array. */ + +int xtensa_insnbuf_size(xtensa_isa isa); + + +/* Allocate an xtensa_insnbuf of the right size. */ + +xtensa_insnbuf xtensa_insnbuf_alloc(xtensa_isa isa); + + +/* Release an xtensa_insnbuf. */ + +void xtensa_insnbuf_free(xtensa_isa isa, xtensa_insnbuf buf); + + +/* + * Conversion between raw memory (char arrays) and our internal + * instruction representation. This is complicated by the Xtensa ISA's + * variable instruction lengths. When converting to chars, the buffer + * must contain a valid instruction so we know how many bytes to copy; + * thus, the "to_chars" function returns the number of bytes copied or + * XTENSA_UNDEFINED on error. The "from_chars" function first reads the + * minimal number of bytes required to decode the instruction length and + * then proceeds to copy the entire instruction into the buffer; if the + * memory does not contain a valid instruction, it copies the maximum + * number of bytes required for the longest Xtensa instruction. The + * "num_chars" argument may be used to limit the number of bytes that + * can be read or written. Otherwise, if "num_chars" is zero, the + * functions may read or write past the end of the code. + */ + +int xtensa_insnbuf_to_chars(xtensa_isa isa, const xtensa_insnbuf insn, + unsigned char *cp, int num_chars); + +void xtensa_insnbuf_from_chars(xtensa_isa isa, xtensa_insnbuf insn, + const unsigned char *cp, int num_chars); + + + +/* ISA information. */ + +/* Initialize the ISA information. */ + +xtensa_isa xtensa_isa_init(void *xtensa_modules, xtensa_isa_status *errno_p, + char **error_msg_p); + + +/* Deallocate an xtensa_isa structure. */ + +void xtensa_isa_free(xtensa_isa isa); + + +/* Get the maximum instruction size in bytes. */ + +int xtensa_isa_maxlength(xtensa_isa isa); + + +/* + * Decode the length in bytes of an instruction in raw memory (not an + * insnbuf). This function reads only the minimal number of bytes + * required to decode the instruction length. Returns + * XTENSA_UNDEFINED on error. + */ + +int xtensa_isa_length_from_chars(xtensa_isa isa, const unsigned char *cp); + + +/* + * Get the number of stages in the processor's pipeline. The pipeline + * stage values returned by other functions in this library will range + * from 0 to N-1, where N is the value returned by this function. + * Note that the stage numbers used here may not correspond to the + * actual processor hardware, e.g., the hardware may have additional + * stages before stage 0. Returns XTENSA_UNDEFINED on error. + */ + +int xtensa_isa_num_pipe_stages(xtensa_isa isa); + + +/* Get the number of various entities that are defined for this processor. */ + +int xtensa_isa_num_formats(xtensa_isa isa); + +int xtensa_isa_num_opcodes(xtensa_isa isa); + +int xtensa_isa_num_regfiles(xtensa_isa isa); + +int xtensa_isa_num_states(xtensa_isa isa); + +int xtensa_isa_num_sysregs(xtensa_isa isa); + +int xtensa_isa_num_interfaces(xtensa_isa isa); + +int xtensa_isa_num_funcUnits(xtensa_isa isa); + + + +/* Instruction formats. */ + +/* Get the name of a format. Returns null on error. */ + +const char *xtensa_format_name(xtensa_isa isa, xtensa_format fmt); + + +/* + * Given a format name, return the format number. Returns + * XTENSA_UNDEFINED if the name is not a valid format. + */ + +xtensa_format xtensa_format_lookup(xtensa_isa isa, const char *fmtname); + + +/* + * Decode the instruction format from a binary instruction buffer. + * Returns XTENSA_UNDEFINED if the format is not recognized. + */ + +xtensa_format xtensa_format_decode(xtensa_isa isa, const xtensa_insnbuf insn); + + +/* + * Set the instruction format field(s) in a binary instruction buffer. + * All the other fields are set to zero. Returns non-zero on error. + */ + +int xtensa_format_encode(xtensa_isa isa, xtensa_format fmt, + xtensa_insnbuf insn); + + +/* + * Find the length (in bytes) of an instruction. Returns + * XTENSA_UNDEFINED on error. + */ + +int xtensa_format_length(xtensa_isa isa, xtensa_format fmt); + + +/* + * Get the number of slots in an instruction. Returns XTENSA_UNDEFINED + * on error. + */ + +int xtensa_format_num_slots(xtensa_isa isa, xtensa_format fmt); + + +/* + * Get the opcode for a no-op in a particular slot. + * Returns XTENSA_UNDEFINED on error. + */ + +xtensa_opcode xtensa_format_slot_nop_opcode(xtensa_isa isa, xtensa_format fmt, + int slot); + + +/* + * Get the bits for a specified slot out of an insnbuf for the + * instruction as a whole and put them into an insnbuf for that one + * slot, and do the opposite to set a slot. Return non-zero on error. + */ + +int xtensa_format_get_slot(xtensa_isa isa, xtensa_format fmt, int slot, + const xtensa_insnbuf insn, xtensa_insnbuf slotbuf); + +int xtensa_format_set_slot(xtensa_isa isa, xtensa_format fmt, int slot, + xtensa_insnbuf insn, const xtensa_insnbuf slotbuf); + + + +/* Opcode information. */ + +/* + * Translate a mnemonic name to an opcode. Returns XTENSA_UNDEFINED if + * the name is not a valid opcode mnemonic. + */ + +xtensa_opcode xtensa_opcode_lookup(xtensa_isa isa, const char *opname); + + +/* + * Decode the opcode for one instruction slot from a binary instruction + * buffer. Returns the opcode or XTENSA_UNDEFINED if the opcode is + * illegal. + */ + +xtensa_opcode xtensa_opcode_decode(xtensa_isa isa, xtensa_format fmt, int slot, + const xtensa_insnbuf slotbuf); + + +/* + * Set the opcode field(s) for an instruction slot. All other fields + * in the slot are set to zero. Returns non-zero if the opcode cannot + * be encoded. + */ + +int xtensa_opcode_encode(xtensa_isa isa, xtensa_format fmt, int slot, + xtensa_insnbuf slotbuf, xtensa_opcode opc); + + +/* Get the mnemonic name for an opcode. Returns null on error. */ + +const char *xtensa_opcode_name(xtensa_isa isa, xtensa_opcode opc); + + +/* Check various properties of opcodes. These functions return 0 if + * the condition is false, 1 if the condition is true, and + * XTENSA_UNDEFINED on error. The instructions are classified as + * follows: + * + * branch: conditional branch; may fall through to next instruction (B*) + * jump: unconditional branch (J, JX, RET*, RF*) + * loop: zero-overhead loop (LOOP*) + * call: unconditional call; control returns to next instruction (CALL*) + * + * For the opcodes that affect control flow in some way, the branch + * target may be specified by an immediate operand or it may be an + * address stored in a register. You can distinguish these by + * checking if the instruction has a PC-relative immediate + * operand. + */ + +int xtensa_opcode_is_branch(xtensa_isa isa, xtensa_opcode opc); + +int xtensa_opcode_is_jump(xtensa_isa isa, xtensa_opcode opc); + +int xtensa_opcode_is_loop(xtensa_isa isa, xtensa_opcode opc); + +int xtensa_opcode_is_call(xtensa_isa isa, xtensa_opcode opc); + + +/* + * Find the number of ordinary operands, state operands, and interface + * operands for an instruction. These return XTENSA_UNDEFINED on + * error. + */ + +int xtensa_opcode_num_operands(xtensa_isa isa, xtensa_opcode opc); + +int xtensa_opcode_num_stateOperands(xtensa_isa isa, xtensa_opcode opc); + +int xtensa_opcode_num_interfaceOperands(xtensa_isa isa, xtensa_opcode opc); + + +/* + * Get functional unit usage requirements for an opcode. Each "use" + * is identified by a <functional unit, pipeline stage> pair. The + * "num_funcUnit_uses" function returns the number of these "uses" or + * XTENSA_UNDEFINED on error. The "funcUnit_use" function returns + * a pointer to a "use" pair or null on error. + */ + +typedef struct xtensa_funcUnit_use_struct { + xtensa_funcUnit unit; + int stage; +} xtensa_funcUnit_use; + +int xtensa_opcode_num_funcUnit_uses(xtensa_isa isa, xtensa_opcode opc); + +xtensa_funcUnit_use *xtensa_opcode_funcUnit_use(xtensa_isa isa, + xtensa_opcode opc, int u); + + + +/* Operand information. */ + +/* Get the name of an operand. Returns null on error. */ + +const char *xtensa_operand_name(xtensa_isa isa, xtensa_opcode opc, int opnd); + + +/* + * Some operands are "invisible", i.e., not explicitly specified in + * assembly language. When assembling an instruction, you need not set + * the values of invisible operands, since they are either hardwired or + * derived from other field values. The values of invisible operands + * can be examined in the same way as other operands, but remember that + * an invisible operand may get its value from another visible one, so + * the entire instruction must be available before examining the + * invisible operand values. This function returns 1 if an operand is + * visible, 0 if it is invisible, or XTENSA_UNDEFINED on error. Note + * that whether an operand is visible is orthogonal to whether it is + * "implicit", i.e., whether it is encoded in a field in the + * instruction. + */ + +int xtensa_operand_is_visible(xtensa_isa isa, xtensa_opcode opc, int opnd); + + +/* + * Check if an operand is an input ('i'), output ('o'), or inout ('m') + * operand. Note: The output operand of a conditional assignment + * (e.g., movnez) appears here as an inout ('m') even if it is declared + * in the TIE code as an output ('o'); this allows the compiler to + * properly handle register allocation for conditional assignments. + * Returns 0 on error. + */ + +char xtensa_operand_inout(xtensa_isa isa, xtensa_opcode opc, int opnd); + + +/* + * Get and set the raw (encoded) value of the field for the specified + * operand. The "set" function does not check if the value fits in the + * field; that is done by the "encode" function below. Both of these + * functions return non-zero on error, e.g., if the field is not defined + * for the specified slot. + */ + +int xtensa_operand_get_field(xtensa_isa isa, xtensa_opcode opc, int opnd, + xtensa_format fmt, int slot, + const xtensa_insnbuf slotbuf, uint32_t *valp); + +int xtensa_operand_set_field(xtensa_isa isa, xtensa_opcode opc, int opnd, + xtensa_format fmt, int slot, + xtensa_insnbuf slotbuf, uint32_t val); + + +/* + * Encode and decode operands. The raw bits in the operand field may + * be encoded in a variety of different ways. These functions hide + * the details of that encoding. The result values are returned through + * the argument pointer. The return value is non-zero on error. + */ + +int xtensa_operand_encode(xtensa_isa isa, xtensa_opcode opc, int opnd, + uint32_t *valp); + +int xtensa_operand_decode(xtensa_isa isa, xtensa_opcode opc, int opnd, + uint32_t *valp); + + +/* + * An operand may be either a register operand or an immediate of some + * sort (e.g., PC-relative or not). The "is_register" function returns + * 0 if the operand is an immediate, 1 if it is a register, and + * XTENSA_UNDEFINED on error. The "regfile" function returns the + * regfile for a register operand, or XTENSA_UNDEFINED on error. + */ + +int xtensa_operand_is_register(xtensa_isa isa, xtensa_opcode opc, int opnd); + +xtensa_regfile xtensa_operand_regfile(xtensa_isa isa, xtensa_opcode opc, + int opnd); + + +/* + * Register operands may span multiple consecutive registers, e.g., a + * 64-bit data type may occupy two 32-bit registers. Only the first + * register is encoded in the operand field. This function specifies + * the number of consecutive registers occupied by this operand. For + * non-register operands, the return value is undefined. Returns + * XTENSA_UNDEFINED on error. + */ + +int xtensa_operand_num_regs(xtensa_isa isa, xtensa_opcode opc, int opnd); + + +/* + * Some register operands do not completely identify the register being + * accessed. For example, the operand value may be added to an internal + * state value. By definition, this implies that the corresponding + * regfile is not allocatable. Unknown registers should generally be + * treated with worst-case assumptions. The function returns 0 if the + * register value is unknown, 1 if known, and XTENSA_UNDEFINED on + * error. + */ + +int xtensa_operand_is_known_reg(xtensa_isa isa, xtensa_opcode opc, int opnd); + + +/* + * Check if an immediate operand is PC-relative. Returns 0 for register + * operands and non-PC-relative immediates, 1 for PC-relative + * immediates, and XTENSA_UNDEFINED on error. + */ + +int xtensa_operand_is_PCrelative(xtensa_isa isa, xtensa_opcode opc, int opnd); + + +/* + * For PC-relative offset operands, the interpretation of the offset may + * vary between opcodes, e.g., is it relative to the current PC or that + * of the next instruction? The following functions are defined to + * perform PC-relative relocations and to undo them (as in the + * disassembler). The "do_reloc" function takes the desired address + * value and the PC of the current instruction and sets the value to the + * corresponding PC-relative offset (which can then be encoded and + * stored into the operand field). The "undo_reloc" function takes the + * unencoded offset value and the current PC and sets the value to the + * appropriate address. The return values are non-zero on error. Note + * that these functions do not replace the encode/decode functions; the + * operands must be encoded/decoded separately and the encode functions + * are responsible for detecting invalid operand values. + */ + +int xtensa_operand_do_reloc(xtensa_isa isa, xtensa_opcode opc, int opnd, + uint32_t *valp, uint32_t pc); + +int xtensa_operand_undo_reloc(xtensa_isa isa, xtensa_opcode opc, int opnd, + uint32_t *valp, uint32_t pc); + + + +/* State Operands. */ + +/* + * Get the state accessed by a state operand. Returns XTENSA_UNDEFINED + * on error. + */ + +xtensa_state xtensa_stateOperand_state(xtensa_isa isa, xtensa_opcode opc, + int stOp); + + +/* + * Check if a state operand is an input ('i'), output ('o'), or inout + * ('m') operand. Returns 0 on error. + */ + +char xtensa_stateOperand_inout(xtensa_isa isa, xtensa_opcode opc, int stOp); + + + +/* Interface Operands. */ + +/* + * Get the external interface accessed by an interface operand. + * Returns XTENSA_UNDEFINED on error. + */ + +xtensa_interface xtensa_interfaceOperand_interface(xtensa_isa isa, + xtensa_opcode opc, + int ifOp); + + + +/* Register Files. */ + +/* + * Regfiles include both "real" regfiles and "views", where a view + * allows a group of adjacent registers in a real "parent" regfile to be + * viewed as a single register. A regfile view has all the same + * properties as its parent except for its (long) name, bit width, number + * of entries, and default ctype. You can use the parent function to + * distinguish these two classes. + */ + +/* + * Look up a regfile by either its name or its abbreviated "short name". + * Returns XTENSA_UNDEFINED on error. The "lookup_shortname" function + * ignores "view" regfiles since they always have the same shortname as + * their parents. + */ + +xtensa_regfile xtensa_regfile_lookup(xtensa_isa isa, const char *name); + +xtensa_regfile xtensa_regfile_lookup_shortname(xtensa_isa isa, + const char *shortname); + + +/* + * Get the name or abbreviated "short name" of a regfile. + * Returns null on error. + */ + +const char *xtensa_regfile_name(xtensa_isa isa, xtensa_regfile rf); + +const char *xtensa_regfile_shortname(xtensa_isa isa, xtensa_regfile rf); + + +/* + * Get the parent regfile of a "view" regfile. If the regfile is not a + * view, the result is the same as the input parameter. Returns + * XTENSA_UNDEFINED on error. + */ + +xtensa_regfile xtensa_regfile_view_parent(xtensa_isa isa, xtensa_regfile rf); + + +/* + * Get the bit width of a regfile or regfile view. + * Returns XTENSA_UNDEFINED on error. + */ + +int xtensa_regfile_num_bits(xtensa_isa isa, xtensa_regfile rf); + + +/* + * Get the number of regfile entries. Returns XTENSA_UNDEFINED on + * error. + */ + +int xtensa_regfile_num_entries(xtensa_isa isa, xtensa_regfile rf); + + + +/* Processor States. */ + +/* Look up a state by name. Returns XTENSA_UNDEFINED on error. */ + +xtensa_state xtensa_state_lookup(xtensa_isa isa, const char *name); + + +/* Get the name for a processor state. Returns null on error. */ + +const char *xtensa_state_name(xtensa_isa isa, xtensa_state st); + + +/* + * Get the bit width for a processor state. + * Returns XTENSA_UNDEFINED on error. + */ + +int xtensa_state_num_bits(xtensa_isa isa, xtensa_state st); + + +/* + * Check if a state is exported from the processor core. Returns 0 if + * the condition is false, 1 if the condition is true, and + * XTENSA_UNDEFINED on error. + */ + +int xtensa_state_is_exported(xtensa_isa isa, xtensa_state st); + + +/* + * Check for a "shared_or" state. Returns 0 if the condition is false, + * 1 if the condition is true, and XTENSA_UNDEFINED on error. + */ + +int xtensa_state_is_shared_or(xtensa_isa isa, xtensa_state st); + + + +/* Sysregs ("special registers" and "user registers"). */ + +/* + * Look up a register by its number and whether it is a "user register" + * or a "special register". Returns XTENSA_UNDEFINED if the sysreg does + * not exist. + */ + +xtensa_sysreg xtensa_sysreg_lookup(xtensa_isa isa, int num, int is_user); + + +/* + * Check if there exists a sysreg with a given name. + * If not, this function returns XTENSA_UNDEFINED. + */ + +xtensa_sysreg xtensa_sysreg_lookup_name(xtensa_isa isa, const char *name); + + +/* Get the name of a sysreg. Returns null on error. */ + +const char *xtensa_sysreg_name(xtensa_isa isa, xtensa_sysreg sysreg); + + +/* Get the register number. Returns XTENSA_UNDEFINED on error. */ + +int xtensa_sysreg_number(xtensa_isa isa, xtensa_sysreg sysreg); + + +/* + * Check if a sysreg is a "special register" or a "user register". + * Returns 0 for special registers, 1 for user registers and + * XTENSA_UNDEFINED on error. + */ + +int xtensa_sysreg_is_user(xtensa_isa isa, xtensa_sysreg sysreg); + + + +/* Interfaces. */ + +/* + * Find an interface by name. The return value is XTENSA_UNDEFINED if + * the specified interface is not found. + */ + +xtensa_interface xtensa_interface_lookup(xtensa_isa isa, const char *ifname); + + +/* Get the name of an interface. Returns null on error. */ + +const char *xtensa_interface_name(xtensa_isa isa, xtensa_interface intf); + + +/* + * Get the bit width for an interface. + * Returns XTENSA_UNDEFINED on error. + */ + +int xtensa_interface_num_bits(xtensa_isa isa, xtensa_interface intf); + + +/* + * Check if an interface is an input ('i') or output ('o') with respect + * to the Xtensa processor core. Returns 0 on error. + */ + +char xtensa_interface_inout(xtensa_isa isa, xtensa_interface intf); + + +/* + * Check if accessing an interface has potential side effects. + * Currently "data" interfaces have side effects and "control" + * interfaces do not. Returns 1 if there are side effects, 0 if not, + * and XTENSA_UNDEFINED on error. + */ + +int xtensa_interface_has_side_effect(xtensa_isa isa, xtensa_interface intf); + + +/* + * Some interfaces may be related such that accessing one interface + * has side effects on a set of related interfaces. The interfaces + * are partitioned into equivalence classes of related interfaces, and + * each class is assigned a unique identifier number. This function + * returns the class identifier for an interface, or XTENSA_UNDEFINED + * on error. These identifiers can be compared to determine if two + * interfaces are related; the specific values of the identifiers have + * no particular meaning otherwise. + */ + +int xtensa_interface_class_id(xtensa_isa isa, xtensa_interface intf); + + +/* Functional Units. */ + +/* + * Find a functional unit by name. The return value is XTENSA_UNDEFINED if + * the specified unit is not found. + */ + +xtensa_funcUnit xtensa_funcUnit_lookup(xtensa_isa isa, const char *fname); + + +/* Get the name of a functional unit. Returns null on error. */ + +const char *xtensa_funcUnit_name(xtensa_isa isa, xtensa_funcUnit fun); + + +/* + * Functional units may be replicated. See how many instances of a + * particular function unit exist. Returns XTENSA_UNDEFINED on error. + */ + +int xtensa_funcUnit_num_copies(xtensa_isa isa, xtensa_funcUnit fun); + + +#ifdef __cplusplus +} +#endif +#endif /* XTENSA_LIBISA_H */ |