1 /* 2 * qemu user cpu loop 3 * 4 * Copyright (c) 2003-2008 Fabrice Bellard 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, see <http://www.gnu.org/licenses/>. 18 */ 19 20 #include "qemu/osdep.h" 21 #include "qemu.h" 22 #include "user-internals.h" 23 #include "cpu_loop-common.h" 24 #include "signal-common.h" 25 26 #define SPARC64_STACK_BIAS 2047 27 28 //#define DEBUG_WIN 29 30 /* WARNING: dealing with register windows _is_ complicated. More info 31 can be found at http://www.sics.se/~psm/sparcstack.html */ 32 static inline int get_reg_index(CPUSPARCState *env, int cwp, int index) 33 { 34 index = (index + cwp * 16) % (16 * env->nwindows); 35 /* wrap handling : if cwp is on the last window, then we use the 36 registers 'after' the end */ 37 if (index < 8 && env->cwp == env->nwindows - 1) 38 index += 16 * env->nwindows; 39 return index; 40 } 41 42 /* save the register window 'cwp1' */ 43 static inline void save_window_offset(CPUSPARCState *env, int cwp1) 44 { 45 unsigned int i; 46 abi_ulong sp_ptr; 47 48 sp_ptr = env->regbase[get_reg_index(env, cwp1, 6)]; 49 #ifdef TARGET_SPARC64 50 if (sp_ptr & 3) 51 sp_ptr += SPARC64_STACK_BIAS; 52 #endif 53 #if defined(DEBUG_WIN) 54 printf("win_overflow: sp_ptr=0x" TARGET_ABI_FMT_lx " save_cwp=%d\n", 55 sp_ptr, cwp1); 56 #endif 57 for(i = 0; i < 16; i++) { 58 /* FIXME - what to do if put_user() fails? */ 59 put_user_ual(env->regbase[get_reg_index(env, cwp1, 8 + i)], sp_ptr); 60 sp_ptr += sizeof(abi_ulong); 61 } 62 } 63 64 static void save_window(CPUSPARCState *env) 65 { 66 #ifndef TARGET_SPARC64 67 unsigned int new_wim; 68 new_wim = ((env->wim >> 1) | (env->wim << (env->nwindows - 1))) & 69 ((1LL << env->nwindows) - 1); 70 save_window_offset(env, cpu_cwp_dec(env, env->cwp - 2)); 71 env->wim = new_wim; 72 #else 73 /* 74 * cansave is zero if the spill trap handler is triggered by `save` and 75 * nonzero if triggered by a `flushw` 76 */ 77 save_window_offset(env, cpu_cwp_dec(env, env->cwp - env->cansave - 2)); 78 env->cansave++; 79 env->canrestore--; 80 #endif 81 } 82 83 static void restore_window(CPUSPARCState *env) 84 { 85 #ifndef TARGET_SPARC64 86 unsigned int new_wim; 87 #endif 88 unsigned int i, cwp1; 89 abi_ulong sp_ptr; 90 91 #ifndef TARGET_SPARC64 92 new_wim = ((env->wim << 1) | (env->wim >> (env->nwindows - 1))) & 93 ((1LL << env->nwindows) - 1); 94 #endif 95 96 /* restore the invalid window */ 97 cwp1 = cpu_cwp_inc(env, env->cwp + 1); 98 sp_ptr = env->regbase[get_reg_index(env, cwp1, 6)]; 99 #ifdef TARGET_SPARC64 100 if (sp_ptr & 3) 101 sp_ptr += SPARC64_STACK_BIAS; 102 #endif 103 #if defined(DEBUG_WIN) 104 printf("win_underflow: sp_ptr=0x" TARGET_ABI_FMT_lx " load_cwp=%d\n", 105 sp_ptr, cwp1); 106 #endif 107 for(i = 0; i < 16; i++) { 108 /* FIXME - what to do if get_user() fails? */ 109 get_user_ual(env->regbase[get_reg_index(env, cwp1, 8 + i)], sp_ptr); 110 sp_ptr += sizeof(abi_ulong); 111 } 112 #ifdef TARGET_SPARC64 113 env->canrestore++; 114 if (env->cleanwin < env->nwindows - 1) 115 env->cleanwin++; 116 env->cansave--; 117 #else 118 env->wim = new_wim; 119 #endif 120 } 121 122 static void flush_windows(CPUSPARCState *env) 123 { 124 int offset, cwp1; 125 126 offset = 1; 127 for(;;) { 128 /* if restore would invoke restore_window(), then we can stop */ 129 cwp1 = cpu_cwp_inc(env, env->cwp + offset); 130 #ifndef TARGET_SPARC64 131 if (env->wim & (1 << cwp1)) 132 break; 133 #else 134 if (env->canrestore == 0) 135 break; 136 env->cansave++; 137 env->canrestore--; 138 #endif 139 save_window_offset(env, cwp1); 140 offset++; 141 } 142 cwp1 = cpu_cwp_inc(env, env->cwp + 1); 143 #ifndef TARGET_SPARC64 144 /* set wim so that restore will reload the registers */ 145 env->wim = 1 << cwp1; 146 #endif 147 #if defined(DEBUG_WIN) 148 printf("flush_windows: nb=%d\n", offset - 1); 149 #endif 150 } 151 152 void cpu_loop (CPUSPARCState *env) 153 { 154 CPUState *cs = env_cpu(env); 155 int trapnr; 156 abi_long ret; 157 158 while (1) { 159 cpu_exec_start(cs); 160 trapnr = cpu_exec(cs); 161 cpu_exec_end(cs); 162 process_queued_cpu_work(cs); 163 164 /* Compute PSR before exposing state. */ 165 if (env->cc_op != CC_OP_FLAGS) { 166 cpu_get_psr(env); 167 } 168 169 switch (trapnr) { 170 #ifndef TARGET_SPARC64 171 case 0x88: 172 case 0x90: 173 #else 174 case 0x110: 175 case 0x16d: 176 #endif 177 ret = do_syscall (env, env->gregs[1], 178 env->regwptr[0], env->regwptr[1], 179 env->regwptr[2], env->regwptr[3], 180 env->regwptr[4], env->regwptr[5], 181 0, 0); 182 if (ret == -QEMU_ERESTARTSYS || ret == -QEMU_ESIGRETURN) { 183 break; 184 } 185 if ((abi_ulong)ret >= (abi_ulong)(-515)) { 186 #if defined(TARGET_SPARC64) && !defined(TARGET_ABI32) 187 env->xcc |= PSR_CARRY; 188 #else 189 env->psr |= PSR_CARRY; 190 #endif 191 ret = -ret; 192 } else { 193 #if defined(TARGET_SPARC64) && !defined(TARGET_ABI32) 194 env->xcc &= ~PSR_CARRY; 195 #else 196 env->psr &= ~PSR_CARRY; 197 #endif 198 } 199 env->regwptr[0] = ret; 200 /* next instruction */ 201 env->pc = env->npc; 202 env->npc = env->npc + 4; 203 break; 204 case 0x83: /* flush windows */ 205 #ifdef TARGET_ABI32 206 case 0x103: 207 #endif 208 flush_windows(env); 209 /* next instruction */ 210 env->pc = env->npc; 211 env->npc = env->npc + 4; 212 break; 213 #ifndef TARGET_SPARC64 214 case TT_WIN_OVF: /* window overflow */ 215 save_window(env); 216 break; 217 case TT_WIN_UNF: /* window underflow */ 218 restore_window(env); 219 break; 220 #else 221 case TT_SPILL: /* window overflow */ 222 save_window(env); 223 break; 224 case TT_FILL: /* window underflow */ 225 restore_window(env); 226 break; 227 #ifndef TARGET_ABI32 228 case 0x16e: 229 flush_windows(env); 230 sparc64_get_context(env); 231 break; 232 case 0x16f: 233 flush_windows(env); 234 sparc64_set_context(env); 235 break; 236 #endif 237 #endif 238 case EXCP_INTERRUPT: 239 /* just indicate that signals should be handled asap */ 240 break; 241 case TT_ILL_INSN: 242 force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLOPC, env->pc); 243 break; 244 case EXCP_DEBUG: 245 force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->pc); 246 break; 247 case EXCP_ATOMIC: 248 cpu_exec_step_atomic(cs); 249 break; 250 default: 251 fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr); 252 cpu_dump_state(cs, stderr, 0); 253 exit(EXIT_FAILURE); 254 } 255 process_pending_signals (env); 256 } 257 } 258 259 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs) 260 { 261 int i; 262 env->pc = regs->pc; 263 env->npc = regs->npc; 264 env->y = regs->y; 265 for(i = 0; i < 8; i++) 266 env->gregs[i] = regs->u_regs[i]; 267 for(i = 0; i < 8; i++) 268 env->regwptr[i] = regs->u_regs[i + 8]; 269 } 270