1 /* 2 * QEMU PowerPC Booke hardware System Emulator 3 * 4 * Copyright (c) 2011 AdaCore 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a copy 7 * of this software and associated documentation files (the "Software"), to deal 8 * in the Software without restriction, including without limitation the rights 9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 10 * copies of the Software, and to permit persons to whom the Software is 11 * furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 22 * THE SOFTWARE. 23 */ 24 #include "qemu/osdep.h" 25 #include "cpu.h" 26 #include "hw/hw.h" 27 #include "hw/ppc/ppc.h" 28 #include "qemu/timer.h" 29 #include "sysemu/sysemu.h" 30 #include "qemu/log.h" 31 #include "hw/loader.h" 32 #include "kvm_ppc.h" 33 34 35 /* Timer Control Register */ 36 37 #define TCR_WP_SHIFT 30 /* Watchdog Timer Period */ 38 #define TCR_WP_MASK (0x3U << TCR_WP_SHIFT) 39 #define TCR_WRC_SHIFT 28 /* Watchdog Timer Reset Control */ 40 #define TCR_WRC_MASK (0x3U << TCR_WRC_SHIFT) 41 #define TCR_WIE (1U << 27) /* Watchdog Timer Interrupt Enable */ 42 #define TCR_DIE (1U << 26) /* Decrementer Interrupt Enable */ 43 #define TCR_FP_SHIFT 24 /* Fixed-Interval Timer Period */ 44 #define TCR_FP_MASK (0x3U << TCR_FP_SHIFT) 45 #define TCR_FIE (1U << 23) /* Fixed-Interval Timer Interrupt Enable */ 46 #define TCR_ARE (1U << 22) /* Auto-Reload Enable */ 47 48 /* Timer Control Register (e500 specific fields) */ 49 50 #define TCR_E500_FPEXT_SHIFT 13 /* Fixed-Interval Timer Period Extension */ 51 #define TCR_E500_FPEXT_MASK (0xf << TCR_E500_FPEXT_SHIFT) 52 #define TCR_E500_WPEXT_SHIFT 17 /* Watchdog Timer Period Extension */ 53 #define TCR_E500_WPEXT_MASK (0xf << TCR_E500_WPEXT_SHIFT) 54 55 /* Timer Status Register */ 56 57 #define TSR_FIS (1U << 26) /* Fixed-Interval Timer Interrupt Status */ 58 #define TSR_DIS (1U << 27) /* Decrementer Interrupt Status */ 59 #define TSR_WRS_SHIFT 28 /* Watchdog Timer Reset Status */ 60 #define TSR_WRS_MASK (0x3U << TSR_WRS_SHIFT) 61 #define TSR_WIS (1U << 30) /* Watchdog Timer Interrupt Status */ 62 #define TSR_ENW (1U << 31) /* Enable Next Watchdog Timer */ 63 64 typedef struct booke_timer_t booke_timer_t; 65 struct booke_timer_t { 66 67 uint64_t fit_next; 68 QEMUTimer *fit_timer; 69 70 uint64_t wdt_next; 71 QEMUTimer *wdt_timer; 72 73 uint32_t flags; 74 }; 75 76 static void booke_update_irq(PowerPCCPU *cpu) 77 { 78 CPUPPCState *env = &cpu->env; 79 80 ppc_set_irq(cpu, PPC_INTERRUPT_DECR, 81 (env->spr[SPR_BOOKE_TSR] & TSR_DIS 82 && env->spr[SPR_BOOKE_TCR] & TCR_DIE)); 83 84 ppc_set_irq(cpu, PPC_INTERRUPT_WDT, 85 (env->spr[SPR_BOOKE_TSR] & TSR_WIS 86 && env->spr[SPR_BOOKE_TCR] & TCR_WIE)); 87 88 ppc_set_irq(cpu, PPC_INTERRUPT_FIT, 89 (env->spr[SPR_BOOKE_TSR] & TSR_FIS 90 && env->spr[SPR_BOOKE_TCR] & TCR_FIE)); 91 } 92 93 /* Return the location of the bit of time base at which the FIT will raise an 94 interrupt */ 95 static uint8_t booke_get_fit_target(CPUPPCState *env, ppc_tb_t *tb_env) 96 { 97 uint8_t fp = (env->spr[SPR_BOOKE_TCR] & TCR_FP_MASK) >> TCR_FP_SHIFT; 98 99 if (tb_env->flags & PPC_TIMER_E500) { 100 /* e500 Fixed-interval timer period extension */ 101 uint32_t fpext = (env->spr[SPR_BOOKE_TCR] & TCR_E500_FPEXT_MASK) 102 >> TCR_E500_FPEXT_SHIFT; 103 fp = 63 - (fp | fpext << 2); 104 } else { 105 fp = env->fit_period[fp]; 106 } 107 108 return fp; 109 } 110 111 /* Return the location of the bit of time base at which the WDT will raise an 112 interrupt */ 113 static uint8_t booke_get_wdt_target(CPUPPCState *env, ppc_tb_t *tb_env) 114 { 115 uint8_t wp = (env->spr[SPR_BOOKE_TCR] & TCR_WP_MASK) >> TCR_WP_SHIFT; 116 117 if (tb_env->flags & PPC_TIMER_E500) { 118 /* e500 Watchdog timer period extension */ 119 uint32_t wpext = (env->spr[SPR_BOOKE_TCR] & TCR_E500_WPEXT_MASK) 120 >> TCR_E500_WPEXT_SHIFT; 121 wp = 63 - (wp | wpext << 2); 122 } else { 123 wp = env->wdt_period[wp]; 124 } 125 126 return wp; 127 } 128 129 static void booke_update_fixed_timer(CPUPPCState *env, 130 uint8_t target_bit, 131 uint64_t *next, 132 QEMUTimer *timer, 133 int tsr_bit) 134 { 135 ppc_tb_t *tb_env = env->tb_env; 136 uint64_t delta_tick, ticks = 0; 137 uint64_t tb; 138 uint64_t period; 139 uint64_t now; 140 141 if (!(env->spr[SPR_BOOKE_TSR] & tsr_bit)) { 142 /* 143 * Don't arm the timer again when the guest has the current 144 * interrupt still pending. Wait for it to ack it. 145 */ 146 return; 147 } 148 149 now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); 150 tb = cpu_ppc_get_tb(tb_env, now, tb_env->tb_offset); 151 period = 1ULL << target_bit; 152 delta_tick = period - (tb & (period - 1)); 153 154 /* the timer triggers only when the selected bit toggles from 0 to 1 */ 155 if (tb & period) { 156 ticks = period; 157 } 158 159 if (ticks + delta_tick < ticks) { 160 /* Overflow, so assume the biggest number we can express. */ 161 ticks = UINT64_MAX; 162 } else { 163 ticks += delta_tick; 164 } 165 166 *next = now + muldiv64(ticks, NANOSECONDS_PER_SECOND, tb_env->tb_freq); 167 if ((*next < now) || (*next > INT64_MAX)) { 168 /* Overflow, so assume the biggest number the qemu timer supports. */ 169 *next = INT64_MAX; 170 } 171 172 /* XXX: If expire time is now. We can't run the callback because we don't 173 * have access to it. So we just set the timer one nanosecond later. 174 */ 175 176 if (*next == now) { 177 (*next)++; 178 } else { 179 /* 180 * There's no point to fake any granularity that's more fine grained 181 * than milliseconds. Anything beyond that just overloads the system. 182 */ 183 *next = MAX(*next, now + SCALE_MS); 184 } 185 186 /* Fire the next timer */ 187 timer_mod(timer, *next); 188 } 189 190 static void booke_decr_cb(void *opaque) 191 { 192 PowerPCCPU *cpu = opaque; 193 CPUPPCState *env = &cpu->env; 194 195 env->spr[SPR_BOOKE_TSR] |= TSR_DIS; 196 booke_update_irq(cpu); 197 198 if (env->spr[SPR_BOOKE_TCR] & TCR_ARE) { 199 /* Do not reload 0, it is already there. It would just trigger 200 * the timer again and lead to infinite loop */ 201 if (env->spr[SPR_BOOKE_DECAR] != 0) { 202 /* Auto Reload */ 203 cpu_ppc_store_decr(env, env->spr[SPR_BOOKE_DECAR]); 204 } 205 } 206 } 207 208 static void booke_fit_cb(void *opaque) 209 { 210 PowerPCCPU *cpu = opaque; 211 CPUPPCState *env = &cpu->env; 212 ppc_tb_t *tb_env; 213 booke_timer_t *booke_timer; 214 215 tb_env = env->tb_env; 216 booke_timer = tb_env->opaque; 217 env->spr[SPR_BOOKE_TSR] |= TSR_FIS; 218 219 booke_update_irq(cpu); 220 221 booke_update_fixed_timer(env, 222 booke_get_fit_target(env, tb_env), 223 &booke_timer->fit_next, 224 booke_timer->fit_timer, 225 TSR_FIS); 226 } 227 228 static void booke_wdt_cb(void *opaque) 229 { 230 PowerPCCPU *cpu = opaque; 231 CPUPPCState *env = &cpu->env; 232 ppc_tb_t *tb_env; 233 booke_timer_t *booke_timer; 234 235 tb_env = env->tb_env; 236 booke_timer = tb_env->opaque; 237 238 /* TODO: There's lots of complicated stuff to do here */ 239 240 booke_update_irq(cpu); 241 242 booke_update_fixed_timer(env, 243 booke_get_wdt_target(env, tb_env), 244 &booke_timer->wdt_next, 245 booke_timer->wdt_timer, 246 TSR_WIS); 247 } 248 249 void store_booke_tsr(CPUPPCState *env, target_ulong val) 250 { 251 PowerPCCPU *cpu = env_archcpu(env); 252 ppc_tb_t *tb_env = env->tb_env; 253 booke_timer_t *booke_timer = tb_env->opaque; 254 255 env->spr[SPR_BOOKE_TSR] &= ~val; 256 kvmppc_clear_tsr_bits(cpu, val); 257 258 if (val & TSR_FIS) { 259 booke_update_fixed_timer(env, 260 booke_get_fit_target(env, tb_env), 261 &booke_timer->fit_next, 262 booke_timer->fit_timer, 263 TSR_FIS); 264 } 265 266 if (val & TSR_WIS) { 267 booke_update_fixed_timer(env, 268 booke_get_wdt_target(env, tb_env), 269 &booke_timer->wdt_next, 270 booke_timer->wdt_timer, 271 TSR_WIS); 272 } 273 274 booke_update_irq(cpu); 275 } 276 277 void store_booke_tcr(CPUPPCState *env, target_ulong val) 278 { 279 PowerPCCPU *cpu = env_archcpu(env); 280 ppc_tb_t *tb_env = env->tb_env; 281 booke_timer_t *booke_timer = tb_env->opaque; 282 283 env->spr[SPR_BOOKE_TCR] = val; 284 kvmppc_set_tcr(cpu); 285 286 booke_update_irq(cpu); 287 288 booke_update_fixed_timer(env, 289 booke_get_fit_target(env, tb_env), 290 &booke_timer->fit_next, 291 booke_timer->fit_timer, 292 TSR_FIS); 293 294 booke_update_fixed_timer(env, 295 booke_get_wdt_target(env, tb_env), 296 &booke_timer->wdt_next, 297 booke_timer->wdt_timer, 298 TSR_WIS); 299 } 300 301 static void ppc_booke_timer_reset_handle(void *opaque) 302 { 303 PowerPCCPU *cpu = opaque; 304 CPUPPCState *env = &cpu->env; 305 306 store_booke_tcr(env, 0); 307 store_booke_tsr(env, -1); 308 } 309 310 /* 311 * This function will be called whenever the CPU state changes. 312 * CPU states are defined "typedef enum RunState". 313 * Regarding timer, When CPU state changes to running after debug halt 314 * or similar cases which takes time then in between final watchdog 315 * expiry happenes. This will cause exit to QEMU and configured watchdog 316 * action will be taken. To avoid this we always clear the watchdog state when 317 * state changes to running. 318 */ 319 static void cpu_state_change_handler(void *opaque, int running, RunState state) 320 { 321 PowerPCCPU *cpu = opaque; 322 CPUPPCState *env = &cpu->env; 323 324 if (!running) { 325 return; 326 } 327 328 /* 329 * Clear watchdog interrupt condition by clearing TSR. 330 */ 331 store_booke_tsr(env, TSR_ENW | TSR_WIS | TSR_WRS_MASK); 332 } 333 334 void ppc_booke_timers_init(PowerPCCPU *cpu, uint32_t freq, uint32_t flags) 335 { 336 ppc_tb_t *tb_env; 337 booke_timer_t *booke_timer; 338 int ret = 0; 339 340 tb_env = g_malloc0(sizeof(ppc_tb_t)); 341 booke_timer = g_malloc0(sizeof(booke_timer_t)); 342 343 cpu->env.tb_env = tb_env; 344 tb_env->flags = flags | PPC_TIMER_BOOKE | PPC_DECR_ZERO_TRIGGERED; 345 346 tb_env->tb_freq = freq; 347 tb_env->decr_freq = freq; 348 tb_env->opaque = booke_timer; 349 tb_env->decr_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, &booke_decr_cb, cpu); 350 351 booke_timer->fit_timer = 352 timer_new_ns(QEMU_CLOCK_VIRTUAL, &booke_fit_cb, cpu); 353 booke_timer->wdt_timer = 354 timer_new_ns(QEMU_CLOCK_VIRTUAL, &booke_wdt_cb, cpu); 355 356 ret = kvmppc_booke_watchdog_enable(cpu); 357 358 if (ret) { 359 /* TODO: Start the QEMU emulated watchdog if not running on KVM. 360 * Also start the QEMU emulated watchdog if KVM does not support 361 * emulated watchdog or somehow it is not enabled (supported but 362 * not enabled is though some bug and requires debugging :)). 363 */ 364 } 365 366 qemu_add_vm_change_state_handler(cpu_state_change_handler, cpu); 367 368 qemu_register_reset(ppc_booke_timer_reset_handle, cpu); 369 } 370