/* Simulator for Atmel's AVR core. Copyright (C) 2009-2015 Free Software Foundation, Inc. Written by Tristan Gingold, AdaCore. This file is part of GDB, the GNU debugger. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . */ #include "config.h" #ifdef HAVE_STRING_H #include #endif #include "bfd.h" #include "libiberty.h" #include "gdb/remote-sim.h" #include "sim-main.h" #include "sim-base.h" #include "sim-options.h" /* As AVR is a 8/16 bits processor, define handy types. */ typedef unsigned short int word; typedef signed short int sword; typedef unsigned char byte; typedef signed char sbyte; /* The only real register. */ unsigned int pc; /* We update a cycle counter. */ static unsigned int cycles = 0; /* If true, the pc needs more than 2 bytes. */ static int avr_pc22; /* Max size of I space (which is always flash on avr). */ #define MAX_AVR_FLASH (128 * 1024) #define PC_MASK (MAX_AVR_FLASH - 1) /* Mac size of D space. */ #define MAX_AVR_SRAM (64 * 1024) #define SRAM_MASK (MAX_AVR_SRAM - 1) /* D space offset in ELF file. */ #define SRAM_VADDR 0x800000 /* Simulator specific ports. */ #define STDIO_PORT 0x52 #define EXIT_PORT 0x4F #define ABORT_PORT 0x49 /* GDB defined register numbers. */ #define AVR_SREG_REGNUM 32 #define AVR_SP_REGNUM 33 #define AVR_PC_REGNUM 34 /* Memory mapped registers. */ #define SREG 0x5F #define REG_SP 0x5D #define EIND 0x5C #define RAMPZ 0x5B #define REGX 0x1a #define REGY 0x1c #define REGZ 0x1e #define REGZ_LO 0x1e #define REGZ_HI 0x1f /* Sreg (status) bits. */ #define SREG_I 0x80 #define SREG_T 0x40 #define SREG_H 0x20 #define SREG_S 0x10 #define SREG_V 0x08 #define SREG_N 0x04 #define SREG_Z 0x02 #define SREG_C 0x01 /* In order to speed up emulation we use a simple approach: a code is associated with each instruction. The pre-decoding occurs usually once when the instruction is first seen. This works well because I&D spaces are separated. Missing opcodes: sleep, spm, wdr (as they are mmcu dependent). */ enum avr_opcode { /* Opcode not yet decoded. */ OP_unknown, OP_bad, OP_nop, OP_rjmp, OP_rcall, OP_ret, OP_reti, OP_break, OP_brbs, OP_brbc, OP_bset, OP_bclr, OP_bld, OP_bst, OP_sbrc, OP_sbrs, OP_eor, OP_and, OP_andi, OP_or, OP_ori, OP_com, OP_swap, OP_neg, OP_out, OP_in, OP_cbi, OP_sbi, OP_sbic, OP_sbis, OP_ldi, OP_cpse, OP_cp, OP_cpi, OP_cpc, OP_sub, OP_sbc, OP_sbiw, OP_adiw, OP_add, OP_adc, OP_subi, OP_sbci, OP_inc, OP_dec, OP_lsr, OP_ror, OP_asr, OP_mul, OP_muls, OP_mulsu, OP_fmul, OP_fmuls, OP_fmulsu, OP_mov, OP_movw, OP_push, OP_pop, OP_st_X, OP_st_dec_X, OP_st_X_inc, OP_st_Y_inc, OP_st_dec_Y, OP_st_Z_inc, OP_st_dec_Z, OP_std_Y, OP_std_Z, OP_ldd_Y, OP_ldd_Z, OP_ld_Z_inc, OP_ld_dec_Z, OP_ld_Y_inc, OP_ld_dec_Y, OP_ld_X, OP_ld_X_inc, OP_ld_dec_X, OP_lpm, OP_lpm_Z, OP_lpm_inc_Z, OP_elpm, OP_elpm_Z, OP_elpm_inc_Z, OP_ijmp, OP_icall, OP_eijmp, OP_eicall, /* 2 words opcodes. */ #define OP_2words OP_jmp OP_jmp, OP_call, OP_sts, OP_lds }; struct avr_insn_cell { /* The insn (16 bits). */ word op; /* Pre-decoding code. */ enum avr_opcode code : 8; /* One byte of additional information. */ byte r; }; /* I&D memories. */ /* TODO: Should be moved to SIM_CPU. */ static struct avr_insn_cell flash[MAX_AVR_FLASH]; static byte sram[MAX_AVR_SRAM]; /* Sign extend a value. */ static int sign_ext (word val, int nb_bits) { if (val & (1 << (nb_bits - 1))) return val | (-1 << nb_bits); return val; } /* Insn field extractors. */ /* Extract xxxx_xxxRx_xxxx_RRRR. */ static inline byte get_r (word op) { return (op & 0xf) | ((op >> 5) & 0x10); } /* Extract xxxx_xxxxx_xxxx_RRRR. */ static inline byte get_r16 (word op) { return 16 + (op & 0xf); } /* Extract xxxx_xxxxx_xxxx_xRRR. */ static inline byte get_r16_23 (word op) { return 16 + (op & 0x7); } /* Extract xxxx_xxxD_DDDD_xxxx. */ static inline byte get_d (word op) { return (op >> 4) & 0x1f; } /* Extract xxxx_xxxx_DDDD_xxxx. */ static inline byte get_d16 (word op) { return 16 + ((op >> 4) & 0x0f); } /* Extract xxxx_xxxx_xDDD_xxxx. */ static inline byte get_d16_23 (word op) { return 16 + ((op >> 4) & 0x07); } /* Extract xxxx_xAAx_xxxx_AAAA. */ static inline byte get_A (word op) { return (op & 0x0f) | ((op & 0x600) >> 5); } /* Extract xxxx_xxxx_AAAA_Axxx. */ static inline byte get_biA (word op) { return (op >> 3) & 0x1f; } /* Extract xxxx_KKKK_xxxx_KKKK. */ static inline byte get_K (word op) { return (op & 0xf) | ((op & 0xf00) >> 4); } /* Extract xxxx_xxKK_KKKK_Kxxx. */ static inline int get_k (word op) { return sign_ext ((op & 0x3f8) >> 3, 7); } /* Extract xxxx_xxxx_xxDD_xxxx. */ static inline byte get_d24 (word op) { return 24 + ((op >> 3) & 6); } /* Extract xxxx_xxxx_KKxx_KKKK. */ static inline byte get_k6 (word op) { return (op & 0xf) | ((op >> 2) & 0x30); } /* Extract xxQx_QQxx_xxxx_xQQQ. */ static inline byte get_q (word op) { return (op & 7) | ((op >> 7) & 0x18)| ((op >> 8) & 0x20); } /* Extract xxxx_xxxx_xxxx_xBBB. */ static inline byte get_b (word op) { return (op & 7); } /* AVR is little endian. */ static inline word read_word (unsigned int addr) { return sram[addr] | (sram[addr + 1] << 8); } static inline void write_word (unsigned int addr, word w) { sram[addr] = w; sram[addr + 1] = w >> 8; } static inline word read_word_post_inc (unsigned int addr) { word v = read_word (addr); write_word (addr, v + 1); return v; } static inline word read_word_pre_dec (unsigned int addr) { word v = read_word (addr) - 1; write_word (addr, v); return v; } static void update_flags_logic (byte res) { sram[SREG] &= ~(SREG_S | SREG_V | SREG_N | SREG_Z); if (res == 0) sram[SREG] |= SREG_Z; if (res & 0x80) sram[SREG] |= SREG_N | SREG_S; } static void update_flags_add (byte r, byte a, byte b) { byte carry; sram[SREG] &= ~(SREG_H | SREG_S | SREG_V | SREG_N | SREG_Z | SREG_C); if (r & 0x80) sram[SREG] |= SREG_N; carry = (a & b) | (a & ~r) | (b & ~r); if (carry & 0x08) sram[SREG] |= SREG_H; if (carry & 0x80) sram[SREG] |= SREG_C; if (((a & b & ~r) | (~a & ~b & r)) & 0x80) sram[SREG] |= SREG_V; if (!(sram[SREG] & SREG_N) ^ !(sram[SREG] & SREG_V)) sram[SREG] |= SREG_S; if (r == 0) sram[SREG] |= SREG_Z; } static void update_flags_sub (byte r, byte a, byte b) { byte carry; sram[SREG] &= ~(SREG_H | SREG_S | SREG_V | SREG_N | SREG_Z | SREG_C); if (r & 0x80) sram[SREG] |= SREG_N; carry = (~a & b) | (b & r) | (r & ~a); if (carry & 0x08) sram[SREG] |= SREG_H; if (carry & 0x80) sram[SREG] |= SREG_C; if (((a & ~b & ~r) | (~a & b & r)) & 0x80) sram[SREG] |= SREG_V; if (!(sram[SREG] & SREG_N) ^ !(sram[SREG] & SREG_V)) sram[SREG] |= SREG_S; /* Note: Z is not set. */ } static enum avr_opcode decode (unsigned int pc) { word op1 = flash[pc].op; switch ((op1 >> 12) & 0x0f) { case 0x0: switch ((op1 >> 10) & 0x3) { case 0x0: switch ((op1 >> 8) & 0x3) { case 0x0: if (op1 == 0) return OP_nop; break; case 0x1: return OP_movw; case 0x2: return OP_muls; case 0x3: if (op1 & 0x80) { if (op1 & 0x08) return OP_fmulsu; else return OP_fmuls; } else { if (op1 & 0x08) return OP_fmul; else return OP_mulsu; } } break; case 0x1: return OP_cpc; case 0x2: flash[pc].r = SREG_C; return OP_sbc; case 0x3: flash[pc].r = 0; return OP_add; } break; case 0x1: switch ((op1 >> 10) & 0x3) { case 0x0: return OP_cpse; case 0x1: return OP_cp; case 0x2: flash[pc].r = 0; return OP_sub; case 0x3: flash[pc].r = SREG_C; return OP_adc; } break; case 0x2: switch ((op1 >> 10) & 0x3) { case 0x0: return OP_and; case 0x1: return OP_eor; case 0x2: return OP_or; case 0x3: return OP_mov; } break; case 0x3: return OP_cpi; case 0x4: return OP_sbci; case 0x5: return OP_subi; case 0x6: return OP_ori; case 0x7: return OP_andi; case 0x8: case 0xa: if (op1 & 0x0200) { if (op1 & 0x0008) { flash[pc].r = get_q (op1); return OP_std_Y; } else { flash[pc].r = get_q (op1); return OP_std_Z; } } else { if (op1 & 0x0008) { flash[pc].r = get_q (op1); return OP_ldd_Y; } else { flash[pc].r = get_q (op1); return OP_ldd_Z; } } break; case 0x9: /* 9xxx */ switch ((op1 >> 8) & 0xf) { case 0x0: case 0x1: switch ((op1 >> 0) & 0xf) { case 0x0: return OP_lds; case 0x1: return OP_ld_Z_inc; case 0x2: return OP_ld_dec_Z; case 0x4: return OP_lpm_Z; case 0x5: return OP_lpm_inc_Z; case 0x6: return OP_elpm_Z; case 0x7: return OP_elpm_inc_Z; case 0x9: return OP_ld_Y_inc; case 0xa: return OP_ld_dec_Y; case 0xc: return OP_ld_X; case 0xd: return OP_ld_X_inc; case 0xe: return OP_ld_dec_X; case 0xf: return OP_pop; } break; case 0x2: case 0x3: switch ((op1 >> 0) & 0xf) { case 0x0: return OP_sts; case 0x1: return OP_st_Z_inc; case 0x2: return OP_st_dec_Z; case 0x9: return OP_st_Y_inc; case 0xa: return OP_st_dec_Y; case 0xc: return OP_st_X; case 0xd: return OP_st_X_inc; case 0xe: return OP_st_dec_X; case 0xf: return OP_push; } break; case 0x4: case 0x5: switch (op1 & 0xf) { case 0x0: return OP_com; case 0x1: return OP_neg; case 0x2: return OP_swap; case 0x3: return OP_inc; case 0x5: flash[pc].r = 0x80; return OP_asr; case 0x6: flash[pc].r = 0; return OP_lsr; case 0x7: return OP_ror; case 0x8: /* 9[45]x8 */ switch ((op1 >> 4) & 0x1f) { case 0x00: case 0x01: case 0x02: case 0x03: case 0x04: case 0x05: case 0x06: case 0x07: return OP_bset; case 0x08: case 0x09: case 0x0a: case 0x0b: case 0x0c: case 0x0d: case 0x0e: case 0x0f: return OP_bclr; case 0x10: return OP_ret; case 0x11: return OP_reti; case 0x19: return OP_break; case 0x1c: return OP_lpm; case 0x1d: return OP_elpm; default: break; } break; case 0x9: /* 9[45]x9 */ switch ((op1 >> 4) & 0x1f) { case 0x00: return OP_ijmp; case 0x01: return OP_eijmp; case 0x10: return OP_icall; case 0x11: return OP_eicall; default: break; } break; case 0xa: return OP_dec; case 0xc: case 0xd: flash[pc].r = ((op1 & 0x1f0) >> 3) | (op1 & 1); return OP_jmp; case 0xe: case 0xf: flash[pc].r = ((op1 & 0x1f0) >> 3) | (op1 & 1); return OP_call; } break; case 0x6: return OP_adiw; case 0x7: return OP_sbiw; case 0x8: return OP_cbi; case 0x9: return OP_sbic; case 0xa: return OP_sbi; case 0xb: return OP_sbis; case 0xc: case 0xd: case 0xe: case 0xf: return OP_mul; } break; case 0xb: flash[pc].r = get_A (op1); if (((op1 >> 11) & 1) == 0) return OP_in; else return OP_out; case 0xc: return OP_rjmp; case 0xd: return OP_rcall; case 0xe: return OP_ldi; case 0xf: switch ((op1 >> 9) & 7) { case 0: case 1: flash[pc].r = 1 << (op1 & 7); return OP_brbs; case 2: case 3: flash[pc].r = 1 << (op1 & 7); return OP_brbc; case 4: if ((op1 & 8) == 0) { flash[pc].r = 1 << (op1 & 7); return OP_bld; } break; case 5: if ((op1 & 8) == 0) { flash[pc].r = 1 << (op1 & 7); return OP_bst; } break; case 6: if ((op1 & 8) == 0) { flash[pc].r = 1 << (op1 & 7); return OP_sbrc; } break; case 7: if ((op1 & 8) == 0) { flash[pc].r = 1 << (op1 & 7); return OP_sbrs; } break; } } return OP_bad; } static void do_call (unsigned int npc) { unsigned int sp = read_word (REG_SP); /* Big endian! */ sram[sp--] = pc; sram[sp--] = pc >> 8; if (avr_pc22) { sram[sp--] = pc >> 16; cycles++; } write_word (REG_SP, sp); pc = npc & PC_MASK; cycles += 3; } static int get_insn_length (unsigned int p) { if (flash[p].code == OP_unknown) flash[p].code = decode(p); if (flash[p].code >= OP_2words) return 2; else return 1; } static unsigned int get_z (void) { return (sram[RAMPZ] << 16) | (sram[REGZ_HI] << 8) | sram[REGZ_LO]; } static unsigned char get_lpm (unsigned int addr) { word w; w = flash[(addr >> 1) & PC_MASK].op; if (addr & 1) w >>= 8; return w; } static void gen_mul (unsigned int res) { write_word (0, res); sram[SREG] &= ~(SREG_Z | SREG_C); if (res == 0) sram[SREG] |= SREG_Z; if (res & 0x8000) sram[SREG] |= SREG_C; cycles++; } static void step_once (SIM_CPU *cpu) { unsigned int ipc; int code; word op; byte res; byte r, d, vd; again: code = flash[pc].code; op = flash[pc].op; #if 0 if (tracing && code != OP_unknown) { if (verbose > 0) { int flags; int i; sim_cb_eprintf (callback, "R00-07:"); for (i = 0; i < 8; i++) sim_cb_eprintf (callback, " %02x", sram[i]); sim_cb_eprintf (callback, " -"); for (i = 8; i < 16; i++) sim_cb_eprintf (callback, " %02x", sram[i]); sim_cb_eprintf (callback, " SP: %02x %02x", sram[REG_SP + 1], sram[REG_SP]); sim_cb_eprintf (callback, "\n"); sim_cb_eprintf (callback, "R16-31:"); for (i = 16; i < 24; i++) sim_cb_eprintf (callback, " %02x", sram[i]); sim_cb_eprintf (callback, " -"); for (i = 24; i < 32; i++) sim_cb_eprintf (callback, " %02x", sram[i]); sim_cb_eprintf (callback, " "); flags = sram[SREG]; for (i = 0; i < 8; i++) sim_cb_eprintf (callback, "%c", flags & (0x80 >> i) ? "ITHSVNZC"[i] : '-'); sim_cb_eprintf (callback, "\n"); } if (!tracing) sim_cb_eprintf (callback, "%06x: %04x\n", 2 * pc, flash[pc].op); else { sim_cb_eprintf (callback, "pc=0x%06x insn=0x%04x code=%d r=%d\n", 2 * pc, flash[pc].op, code, flash[pc].r); disassemble_insn (CPU_STATE (cpu), pc); sim_cb_eprintf (callback, "\n"); } } #endif ipc = pc; pc = (pc + 1) & PC_MASK; cycles++; switch (code) { case OP_unknown: flash[ipc].code = decode(ipc); pc = ipc; cycles--; goto again; case OP_nop: break; case OP_jmp: /* 2 words instruction, but we don't care about the pc. */ pc = ((flash[ipc].r << 16) | flash[ipc + 1].op) & PC_MASK; cycles += 2; break; case OP_eijmp: pc = ((sram[EIND] << 16) | read_word (REGZ)) & PC_MASK; cycles += 2; break; case OP_ijmp: pc = read_word (REGZ) & PC_MASK; cycles += 1; break; case OP_call: /* 2 words instruction. */ pc++; do_call ((flash[ipc].r << 16) | flash[ipc + 1].op); break; case OP_eicall: do_call ((sram[EIND] << 16) | read_word (REGZ)); break; case OP_icall: do_call (read_word (REGZ)); break; case OP_rcall: do_call (pc + sign_ext (op & 0xfff, 12)); break; case OP_reti: sram[SREG] |= SREG_I; /* Fall through */ case OP_ret: { unsigned int sp = read_word (REG_SP); if (avr_pc22) { pc = sram[++sp] << 16; cycles++; } else pc = 0; pc |= sram[++sp] << 8; pc |= sram[++sp]; write_word (REG_SP, sp); } cycles += 3; break; case OP_break: /* Stop on this address. */ sim_engine_halt (CPU_STATE (cpu), cpu, NULL, pc, sim_stopped, SIM_SIGTRAP); pc = ipc; break; case OP_bld: d = get_d (op); r = flash[ipc].r; if (sram[SREG] & SREG_T) sram[d] |= r; else sram[d] &= ~r; break; case OP_bst: if (sram[get_d (op)] & flash[ipc].r) sram[SREG] |= SREG_T; else sram[SREG] &= ~SREG_T; break; case OP_sbrc: case OP_sbrs: if (((sram[get_d (op)] & flash[ipc].r) == 0) ^ ((op & 0x0200) != 0)) { int l = get_insn_length(pc); pc += l; cycles += l; } break; case OP_push: { unsigned int sp = read_word (REG_SP); sram[sp--] = sram[get_d (op)]; write_word (REG_SP, sp); } cycles++; break; case OP_pop: { unsigned int sp = read_word (REG_SP); sram[get_d (op)] = sram[++sp]; write_word (REG_SP, sp); } cycles++; break; case OP_bclr: sram[SREG] &= ~(1 << ((op >> 4) & 0x7)); break; case OP_bset: sram[SREG] |= 1 << ((op >> 4) & 0x7); break; case OP_rjmp: pc = (pc + sign_ext (op & 0xfff, 12)) & PC_MASK; cycles++; break; case OP_eor: d = get_d (op); res = sram[d] ^ sram[get_r (op)]; sram[d] = res; update_flags_logic (res); break; case OP_and: d = get_d (op); res = sram[d] & sram[get_r (op)]; sram[d] = res; update_flags_logic (res); break; case OP_andi: d = get_d16 (op); res = sram[d] & get_K (op); sram[d] = res; update_flags_logic (res); break; case OP_or: d = get_d (op); res = sram[d] | sram[get_r (op)]; sram[d] = res; update_flags_logic (res); break; case OP_ori: d = get_d16 (op); res = sram[d] | get_K (op); sram[d] = res; update_flags_logic (res); break; case OP_com: d = get_d (op); res = ~sram[d]; sram[d] = res; update_flags_logic (res); sram[SREG] |= SREG_C; break; case OP_swap: d = get_d (op); vd = sram[d]; sram[d] = (vd >> 4) | (vd << 4); break; case OP_neg: d = get_d (op); vd = sram[d]; res = -vd; sram[d] = res; sram[SREG] &= ~(SREG_H | SREG_S | SREG_V | SREG_N | SREG_Z | SREG_C); if (res == 0) sram[SREG] |= SREG_Z; else sram[SREG] |= SREG_C; if (res == 0x80) sram[SREG] |= SREG_V | SREG_N; else if (res & 0x80) sram[SREG] |= SREG_N | SREG_S; if ((res | vd) & 0x08) sram[SREG] |= SREG_H; break; case OP_inc: d = get_d (op); res = sram[d] + 1; sram[d] = res; sram[SREG] &= ~(SREG_S | SREG_V | SREG_N | SREG_Z); if (res == 0x80) sram[SREG] |= SREG_V | SREG_N; else if (res & 0x80) sram[SREG] |= SREG_N | SREG_S; else if (res == 0) sram[SREG] |= SREG_Z; break; case OP_dec: d = get_d (op); res = sram[d] - 1; sram[d] = res; sram[SREG] &= ~(SREG_S | SREG_V | SREG_N | SREG_Z); if (res == 0x7f) sram[SREG] |= SREG_V | SREG_S; else if (res & 0x80) sram[SREG] |= SREG_N | SREG_S; else if (res == 0) sram[SREG] |= SREG_Z; break; case OP_lsr: case OP_asr: d = get_d (op); vd = sram[d]; res = (vd >> 1) | (vd & flash[ipc].r); sram[d] = res; sram[SREG] &= ~(SREG_S | SREG_V | SREG_N | SREG_Z | SREG_C); if (vd & 1) sram[SREG] |= SREG_C | SREG_S; if (res & 0x80) sram[SREG] |= SREG_N; if (!(sram[SREG] & SREG_N) ^ !(sram[SREG] & SREG_C)) sram[SREG] |= SREG_V; if (res == 0) sram[SREG] |= SREG_Z; break; case OP_ror: d = get_d (op); vd = sram[d]; res = vd >> 1 | (sram[SREG] << 7); sram[d] = res; sram[SREG] &= ~(SREG_S | SREG_V | SREG_N | SREG_Z | SREG_C); if (vd & 1) sram[SREG] |= SREG_C | SREG_S; if (res & 0x80) sram[SREG] |= SREG_N; if (!(sram[SREG] & SREG_N) ^ !(sram[SREG] & SREG_C)) sram[SREG] |= SREG_V; if (res == 0) sram[SREG] |= SREG_Z; break; case OP_mul: gen_mul ((word)sram[get_r (op)] * (word)sram[get_d (op)]); break; case OP_muls: gen_mul ((sword)(sbyte)sram[get_r16 (op)] * (sword)(sbyte)sram[get_d16 (op)]); break; case OP_mulsu: gen_mul ((sword)(word)sram[get_r16_23 (op)] * (sword)(sbyte)sram[get_d16_23 (op)]); break; case OP_fmul: gen_mul (((word)sram[get_r16_23 (op)] * (word)sram[get_d16_23 (op)]) << 1); break; case OP_fmuls: gen_mul (((sword)(sbyte)sram[get_r16_23 (op)] * (sword)(sbyte)sram[get_d16_23 (op)]) << 1); break; case OP_fmulsu: gen_mul (((sword)(word)sram[get_r16_23 (op)] * (sword)(sbyte)sram[get_d16_23 (op)]) << 1); break; case OP_adc: case OP_add: r = sram[get_r (op)]; d = get_d (op); vd = sram[d]; res = r + vd + (sram[SREG] & flash[ipc].r); sram[d] = res; update_flags_add (res, vd, r); break; case OP_sub: d = get_d (op); vd = sram[d]; r = sram[get_r (op)]; res = vd - r; sram[d] = res; update_flags_sub (res, vd, r); if (res == 0) sram[SREG] |= SREG_Z; break; case OP_sbc: { byte old = sram[SREG]; d = get_d (op); vd = sram[d]; r = sram[get_r (op)]; res = vd - r - (old & SREG_C); sram[d] = res; update_flags_sub (res, vd, r); if (res == 0 && (old & SREG_Z)) sram[SREG] |= SREG_Z; } break; case OP_subi: d = get_d16 (op); vd = sram[d]; r = get_K (op); res = vd - r; sram[d] = res; update_flags_sub (res, vd, r); if (res == 0) sram[SREG] |= SREG_Z; break; case OP_sbci: { byte old = sram[SREG]; d = get_d16 (op); vd = sram[d]; r = get_K (op); res = vd - r - (old & SREG_C); sram[d] = res; update_flags_sub (res, vd, r); if (res == 0 && (old & SREG_Z)) sram[SREG] |= SREG_Z; } break; case OP_mov: sram[get_d (op)] = sram[get_r (op)]; break; case OP_movw: d = (op & 0xf0) >> 3; r = (op & 0x0f) << 1; sram[d] = sram[r]; sram[d + 1] = sram[r + 1]; break; case OP_out: d = get_A (op) + 0x20; res = sram[get_d (op)]; sram[d] = res; if (d == STDIO_PORT) putchar (res); else if (d == EXIT_PORT) sim_engine_halt (CPU_STATE (cpu), cpu, NULL, pc, sim_exited, 0); else if (d == ABORT_PORT) sim_engine_halt (CPU_STATE (cpu), cpu, NULL, pc, sim_exited, 1); break; case OP_in: d = get_A (op) + 0x20; sram[get_d (op)] = sram[d]; break; case OP_cbi: d = get_biA (op) + 0x20; sram[d] &= ~(1 << get_b(op)); break; case OP_sbi: d = get_biA (op) + 0x20; sram[d] |= 1 << get_b(op); break; case OP_sbic: if (!(sram[get_biA (op) + 0x20] & 1 << get_b(op))) { int l = get_insn_length(pc); pc += l; cycles += l; } break; case OP_sbis: if (sram[get_biA (op) + 0x20] & 1 << get_b(op)) { int l = get_insn_length(pc); pc += l; cycles += l; } break; case OP_ldi: res = get_K (op); d = get_d16 (op); sram[d] = res; break; case OP_lds: sram[get_d (op)] = sram[flash[pc].op]; pc++; cycles++; break; case OP_sts: sram[flash[pc].op] = sram[get_d (op)]; pc++; cycles++; break; case OP_cpse: if (sram[get_r (op)] == sram[get_d (op)]) { int l = get_insn_length(pc); pc += l; cycles += l; } break; case OP_cp: r = sram[get_r (op)]; d = sram[get_d (op)]; res = d - r; update_flags_sub (res, d, r); if (res == 0) sram[SREG] |= SREG_Z; break; case OP_cpi: r = get_K (op); d = sram[get_d16 (op)]; res = d - r; update_flags_sub (res, d, r); if (res == 0) sram[SREG] |= SREG_Z; break; case OP_cpc: { byte old = sram[SREG]; d = sram[get_d (op)]; r = sram[get_r (op)]; res = d - r - (old & SREG_C); update_flags_sub (res, d, r); if (res == 0 && (old & SREG_Z)) sram[SREG] |= SREG_Z; } break; case OP_brbc: if (!(sram[SREG] & flash[ipc].r)) { pc = (pc + get_k (op)) & PC_MASK; cycles++; } break; case OP_brbs: if (sram[SREG] & flash[ipc].r) { pc = (pc + get_k (op)) & PC_MASK; cycles++; } break; case OP_lpm: sram[0] = get_lpm (read_word (REGZ)); cycles += 2; break; case OP_lpm_Z: sram[get_d (op)] = get_lpm (read_word (REGZ)); cycles += 2; break; case OP_lpm_inc_Z: sram[get_d (op)] = get_lpm (read_word_post_inc (REGZ)); cycles += 2; break; case OP_elpm: sram[0] = get_lpm (get_z ()); cycles += 2; break; case OP_elpm_Z: sram[get_d (op)] = get_lpm (get_z ()); cycles += 2; break; case OP_elpm_inc_Z: { unsigned int z = get_z (); sram[get_d (op)] = get_lpm (z); z++; sram[REGZ_LO] = z; sram[REGZ_HI] = z >> 8; sram[RAMPZ] = z >> 16; } cycles += 2; break; case OP_ld_Z_inc: sram[get_d (op)] = sram[read_word_post_inc (REGZ) & SRAM_MASK]; cycles++; break; case OP_ld_dec_Z: sram[get_d (op)] = sram[read_word_pre_dec (REGZ) & SRAM_MASK]; cycles++; break; case OP_ld_X_inc: sram[get_d (op)] = sram[read_word_post_inc (REGX) & SRAM_MASK]; cycles++; break; case OP_ld_dec_X: sram[get_d (op)] = sram[read_word_pre_dec (REGX) & SRAM_MASK]; cycles++; break; case OP_ld_Y_inc: sram[get_d (op)] = sram[read_word_post_inc (REGY) & SRAM_MASK]; cycles++; break; case OP_ld_dec_Y: sram[get_d (op)] = sram[read_word_pre_dec (REGY) & SRAM_MASK]; cycles++; break; case OP_st_X: sram[read_word (REGX) & SRAM_MASK] = sram[get_d (op)]; cycles++; break; case OP_st_X_inc: sram[read_word_post_inc (REGX) & SRAM_MASK] = sram[get_d (op)]; cycles++; break; case OP_st_dec_X: sram[read_word_pre_dec (REGX) & SRAM_MASK] = sram[get_d (op)]; cycles++; break; case OP_st_Z_inc: sram[read_word_post_inc (REGZ) & SRAM_MASK] = sram[get_d (op)]; cycles++; break; case OP_st_dec_Z: sram[read_word_pre_dec (REGZ) & SRAM_MASK] = sram[get_d (op)]; cycles++; break; case OP_st_Y_inc: sram[read_word_post_inc (REGY) & SRAM_MASK] = sram[get_d (op)]; cycles++; break; case OP_st_dec_Y: sram[read_word_pre_dec (REGY) & SRAM_MASK] = sram[get_d (op)]; cycles++; break; case OP_std_Y: sram[read_word (REGY) + flash[ipc].r] = sram[get_d (op)]; cycles++; break; case OP_std_Z: sram[read_word (REGZ) + flash[ipc].r] = sram[get_d (op)]; cycles++; break; case OP_ldd_Z: sram[get_d (op)] = sram[read_word (REGZ) + flash[ipc].r]; cycles++; break; case OP_ldd_Y: sram[get_d (op)] = sram[read_word (REGY) + flash[ipc].r]; cycles++; break; case OP_ld_X: sram[get_d (op)] = sram[read_word (REGX) & SRAM_MASK]; cycles++; break; case OP_sbiw: { word wk = get_k6 (op); word wres; word wr; d = get_d24 (op); wr = read_word (d); wres = wr - wk; sram[SREG] &= ~(SREG_S | SREG_V | SREG_N | SREG_Z | SREG_C); if (wres == 0) sram[SREG] |= SREG_Z; if (wres & 0x8000) sram[SREG] |= SREG_N; if (wres & ~wr & 0x8000) sram[SREG] |= SREG_C; if (~wres & wr & 0x8000) sram[SREG] |= SREG_V; if (((~wres & wr) ^ wres) & 0x8000) sram[SREG] |= SREG_S; write_word (d, wres); } cycles++; break; case OP_adiw: { word wk = get_k6 (op); word wres; word wr; d = get_d24 (op); wr = read_word (d); wres = wr + wk; sram[SREG] &= ~(SREG_S | SREG_V | SREG_N | SREG_Z | SREG_C); if (wres == 0) sram[SREG] |= SREG_Z; if (wres & 0x8000) sram[SREG] |= SREG_N; if (~wres & wr & 0x8000) sram[SREG] |= SREG_C; if (wres & ~wr & 0x8000) sram[SREG] |= SREG_V; if (((wres & ~wr) ^ wres) & 0x8000) sram[SREG] |= SREG_S; write_word (d, wres); } cycles++; break; case OP_bad: sim_engine_halt (CPU_STATE (cpu), cpu, NULL, pc, sim_signalled, SIM_SIGILL); default: sim_engine_halt (CPU_STATE (cpu), cpu, NULL, pc, sim_signalled, SIM_SIGILL); } } void sim_engine_run (SIM_DESC sd, int next_cpu_nr, /* ignore */ int nr_cpus, /* ignore */ int siggnal) /* ignore */ { SIM_CPU *cpu; SIM_ASSERT (STATE_MAGIC (sd) == SIM_MAGIC_NUMBER); cpu = STATE_CPU (sd, 0); while (1) { step_once (cpu); if (sim_events_tick (sd)) sim_events_process (sd); } } int sim_write (SIM_DESC sd, SIM_ADDR addr, const unsigned char *buffer, int size) { int osize = size; if (addr >= 0 && addr < SRAM_VADDR) { while (size > 0 && addr < (MAX_AVR_FLASH << 1)) { word val = flash[addr >> 1].op; if (addr & 1) val = (val & 0xff) | (buffer[0] << 8); else val = (val & 0xff00) | buffer[0]; flash[addr >> 1].op = val; flash[addr >> 1].code = OP_unknown; addr++; buffer++; size--; } return osize - size; } else if (addr >= SRAM_VADDR && addr < SRAM_VADDR + MAX_AVR_SRAM) { addr -= SRAM_VADDR; if (addr + size > MAX_AVR_SRAM) size = MAX_AVR_SRAM - addr; memcpy (sram + addr, buffer, size); return size; } else return 0; } int sim_read (SIM_DESC sd, SIM_ADDR addr, unsigned char *buffer, int size) { int osize = size; if (addr >= 0 && addr < SRAM_VADDR) { while (size > 0 && addr < (MAX_AVR_FLASH << 1)) { word val = flash[addr >> 1].op; if (addr & 1) val >>= 8; *buffer++ = val; addr++; size--; } return osize - size; } else if (addr >= SRAM_VADDR && addr < SRAM_VADDR + MAX_AVR_SRAM) { addr -= SRAM_VADDR; if (addr + size > MAX_AVR_SRAM) size = MAX_AVR_SRAM - addr; memcpy (buffer, sram + addr, size); return size; } else { /* Avoid errors. */ memset (buffer, 0, size); return size; } } static int avr_reg_store (SIM_CPU *cpu, int rn, unsigned char *memory, int length) { if (rn < 32 && length == 1) { sram[rn] = *memory; return 1; } if (rn == AVR_SREG_REGNUM && length == 1) { sram[SREG] = *memory; return 1; } if (rn == AVR_SP_REGNUM && length == 2) { sram[REG_SP] = memory[0]; sram[REG_SP + 1] = memory[1]; return 2; } if (rn == AVR_PC_REGNUM && length == 4) { pc = (memory[0] >> 1) | (memory[1] << 7) | (memory[2] << 15) | (memory[3] << 23); pc &= PC_MASK; return 4; } return 0; } static int avr_reg_fetch (SIM_CPU *cpu, int rn, unsigned char *memory, int length) { if (rn < 32 && length == 1) { *memory = sram[rn]; return 1; } if (rn == AVR_SREG_REGNUM && length == 1) { *memory = sram[SREG]; return 1; } if (rn == AVR_SP_REGNUM && length == 2) { memory[0] = sram[REG_SP]; memory[1] = sram[REG_SP + 1]; return 2; } if (rn == AVR_PC_REGNUM && length == 4) { memory[0] = pc << 1; memory[1] = pc >> 7; memory[2] = pc >> 15; memory[3] = pc >> 23; return 4; } return 0; } static sim_cia avr_pc_get (sim_cpu *cpu) { return pc; } static void avr_pc_set (sim_cpu *cpu, sim_cia _pc) { pc = _pc; } static void free_state (SIM_DESC sd) { if (STATE_MODULES (sd) != NULL) sim_module_uninstall (sd); sim_cpu_free_all (sd); sim_state_free (sd); } SIM_DESC sim_open (SIM_OPEN_KIND kind, host_callback *cb, struct bfd *abfd, char **argv) { int i; SIM_DESC sd = sim_state_alloc (kind, cb); SIM_ASSERT (STATE_MAGIC (sd) == SIM_MAGIC_NUMBER); /* The cpu data is kept in a separately allocated chunk of memory. */ if (sim_cpu_alloc_all (sd, 1, /*cgen_cpu_max_extra_bytes ()*/0) != SIM_RC_OK) { free_state (sd); return 0; } STATE_WATCHPOINTS (sd)->pc = &pc; STATE_WATCHPOINTS (sd)->sizeof_pc = sizeof (pc); if (sim_pre_argv_init (sd, argv[0]) != SIM_RC_OK) { free_state (sd); return 0; } /* getopt will print the error message so we just have to exit if this fails. FIXME: Hmmm... in the case of gdb we need getopt to call print_filtered. */ if (sim_parse_args (sd, argv) != SIM_RC_OK) { free_state (sd); return 0; } /* Check for/establish the a reference program image. */ if (sim_analyze_program (sd, (STATE_PROG_ARGV (sd) != NULL ? *STATE_PROG_ARGV (sd) : NULL), abfd) != SIM_RC_OK) { free_state (sd); return 0; } /* Configure/verify the target byte order and other runtime configuration options. */ if (sim_config (sd) != SIM_RC_OK) { sim_module_uninstall (sd); return 0; } if (sim_post_argv_init (sd) != SIM_RC_OK) { /* Uninstall the modules to avoid memory leaks, file descriptor leaks, etc. */ sim_module_uninstall (sd); return 0; } /* CPU specific initialization. */ for (i = 0; i < MAX_NR_PROCESSORS; ++i) { SIM_CPU *cpu = STATE_CPU (sd, i); CPU_REG_FETCH (cpu) = avr_reg_fetch; CPU_REG_STORE (cpu) = avr_reg_store; CPU_PC_FETCH (cpu) = avr_pc_get; CPU_PC_STORE (cpu) = avr_pc_set; } /* Clear all the memory. */ memset (sram, 0, sizeof (sram)); memset (flash, 0, sizeof (flash)); return sd; } SIM_RC sim_create_inferior (SIM_DESC sd, struct bfd *abfd, char **argv, char **env) { /* Set the PC. */ if (abfd != NULL) pc = bfd_get_start_address (abfd); else pc = 0; if (abfd != NULL) avr_pc22 = (bfd_get_mach (abfd) >= bfd_mach_avr6); return SIM_RC_OK; }