hw/timer/stm32f2xx_timer.c

   1 /*
   2  * STM32F2XX Timer
   3  *
   4  * Copyright (c) 2014 Alistair Francis <alistair@alistair23.me>
   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
  25 #include "qemu/osdep.h"
  26 #include "hw/timer/stm32f2xx_timer.h"
  27
  28 #ifndef STM_TIMER_ERR_DEBUG
  29 #define STM_TIMER_ERR_DEBUG 0
  30 #endif
  31
  32 #define DB_PRINT_L(lvl, fmt, args...) do { \
  33     if (STM_TIMER_ERR_DEBUG >= lvl) { \
  34         qemu_log("%s: " fmt, __func__, ## args); \
  35     } \
  36 } while (0);
  37
  38 #define DB_PRINT(fmt, args...) DB_PRINT_L(1, fmt, ## args)
  39
  40 static void stm32f2xx_timer_set_alarm(STM32F2XXTimerState *s, int64_t now);
  41
  42 static void stm32f2xx_timer_interrupt(void *opaque)
  43 {
  44     STM32F2XXTimerState *s = opaque;
  45
  46     DB_PRINT("Interrupt\n");
  47
  48     if (s->tim_dier & TIM_DIER_UIE && s->tim_cr1 & TIM_CR1_CEN) {
  49         s->tim_sr |= 1;
  50         qemu_irq_pulse(s->irq);
  51         stm32f2xx_timer_set_alarm(s, s->hit_time);
  52     }
  53 }
  54
  55 static inline int64_t stm32f2xx_ns_to_ticks(STM32F2XXTimerState *s, int64_t t)
  56 {
  57     return muldiv64(t, s->freq_hz, 1000000000ULL) / (s->tim_psc + 1);
  58 }
  59
  60 static void stm32f2xx_timer_set_alarm(STM32F2XXTimerState *s, int64_t now)
  61 {
  62     uint64_t ticks;
  63     int64_t now_ticks;
  64
  65     if (s->tim_arr == 0) {
  66         return;
  67     }
  68
  69     DB_PRINT("Alarm set at: 0x%x\n", s->tim_cr1);
  70
  71     now_ticks = stm32f2xx_ns_to_ticks(s, now);
  72     ticks = s->tim_arr - (now_ticks - s->tick_offset);
  73
  74     DB_PRINT("Alarm set in %d ticks\n", (int) ticks);
  75
  76     s->hit_time = muldiv64((ticks + (uint64_t) now_ticks) * (s->tim_psc + 1),
  77                                1000000000ULL, s->freq_hz);
  78
  79     timer_mod(s->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + s->hit_time);
  80     DB_PRINT("Wait Time: %" PRId64 " ticks\n", s->hit_time);
  81 }
  82
  83 static void stm32f2xx_timer_reset(DeviceState *dev)
  84 {
  85     STM32F2XXTimerState *s = STM32F2XXTIMER(dev);
  86     int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
  87
  88     s->tim_cr1 = 0;
  89     s->tim_cr2 = 0;
  90     s->tim_smcr = 0;
  91     s->tim_dier = 0;
  92     s->tim_sr = 0;
  93     s->tim_egr = 0;
  94     s->tim_ccmr1 = 0;
  95     s->tim_ccmr2 = 0;
  96     s->tim_ccer = 0;
  97     s->tim_psc = 0;
  98     s->tim_arr = 0;
  99     s->tim_ccr1 = 0;
 100     s->tim_ccr2 = 0;
 101     s->tim_ccr3 = 0;
 102     s->tim_ccr4 = 0;
 103     s->tim_dcr = 0;
 104     s->tim_dmar = 0;
 105     s->tim_or = 0;
 106
 107     s->tick_offset = stm32f2xx_ns_to_ticks(s, now);
 108 }
 109
 110 static uint64_t stm32f2xx_timer_read(void *opaque, hwaddr offset,
 111                            unsigned size)
 112 {
 113     STM32F2XXTimerState *s = opaque;
 114
 115     DB_PRINT("Read 0x%"HWADDR_PRIx"\n", offset);
 116
 117     switch (offset) {
 118     case TIM_CR1:
 119         return s->tim_cr1;
 120     case TIM_CR2:
 121         return s->tim_cr2;
 122     case TIM_SMCR:
 123         return s->tim_smcr;
 124     case TIM_DIER:
 125         return s->tim_dier;
 126     case TIM_SR:
 127         return s->tim_sr;
 128     case TIM_EGR:
 129         return s->tim_egr;
 130     case TIM_CCMR1:
 131         return s->tim_ccmr1;
 132     case TIM_CCMR2:
 133         return s->tim_ccmr2;
 134     case TIM_CCER:
 135         return s->tim_ccer;
 136     case TIM_CNT:
 137         return stm32f2xx_ns_to_ticks(s, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL)) -
 138                s->tick_offset;
 139     case TIM_PSC:
 140         return s->tim_psc;
 141     case TIM_ARR:
 142         return s->tim_arr;
 143     case TIM_CCR1:
 144         return s->tim_ccr1;
 145     case TIM_CCR2:
 146         return s->tim_ccr2;
 147     case TIM_CCR3:
 148         return s->tim_ccr3;
 149     case TIM_CCR4:
 150         return s->tim_ccr4;
 151     case TIM_DCR:
 152         return s->tim_dcr;
 153     case TIM_DMAR:
 154         return s->tim_dmar;
 155     case TIM_OR:
 156         return s->tim_or;
 157     default:
 158         qemu_log_mask(LOG_GUEST_ERROR,
 159                       "%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, offset);
 160     }
 161
 162     return 0;
 163 }
 164
 165 static void stm32f2xx_timer_write(void *opaque, hwaddr offset,
 166                         uint64_t val64, unsigned size)
 167 {
 168     STM32F2XXTimerState *s = opaque;
 169     uint32_t value = val64;
 170     int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
 171     uint32_t timer_val = 0;
 172
 173     DB_PRINT("Write 0x%x, 0x%"HWADDR_PRIx"\n", value, offset);
 174
 175     switch (offset) {
 176     case TIM_CR1:
 177         s->tim_cr1 = value;
 178         return;
 179     case TIM_CR2:
 180         s->tim_cr2 = value;
 181         return;
 182     case TIM_SMCR:
 183         s->tim_smcr = value;
 184         return;
 185     case TIM_DIER:
 186         s->tim_dier = value;
 187         return;
 188     case TIM_SR:
 189         /* This is set by hardware and cleared by software */
 190         s->tim_sr &= value;
 191         return;
 192     case TIM_EGR:
 193         s->tim_egr = value;
 194         if (s->tim_egr & TIM_EGR_UG) {
 195             timer_val = 0;
 196             break;
 197         }
 198         return;
 199     case TIM_CCMR1:
 200         s->tim_ccmr1 = value;
 201         return;
 202     case TIM_CCMR2:
 203         s->tim_ccmr2 = value;
 204         return;
 205     case TIM_CCER:
 206         s->tim_ccer = value;
 207         return;
 208     case TIM_PSC:
 209         timer_val = stm32f2xx_ns_to_ticks(s, now) - s->tick_offset;
 210         s->tim_psc = value;
 211         value = timer_val;
 212         break;
 213     case TIM_CNT:
 214         timer_val = value;
 215         break;
 216     case TIM_ARR:
 217         s->tim_arr = value;
 218         stm32f2xx_timer_set_alarm(s, now);
 219         return;
 220     case TIM_CCR1:
 221         s->tim_ccr1 = value;
 222         return;
 223     case TIM_CCR2:
 224         s->tim_ccr2 = value;
 225         return;
 226     case TIM_CCR3:
 227         s->tim_ccr3 = value;
 228         return;
 229     case TIM_CCR4:
 230         s->tim_ccr4 = value;
 231         return;
 232     case TIM_DCR:
 233         s->tim_dcr = value;
 234         return;
 235     case TIM_DMAR:
 236         s->tim_dmar = value;
 237         return;
 238     case TIM_OR:
 239         s->tim_or = value;
 240         return;
 241     default:
 242         qemu_log_mask(LOG_GUEST_ERROR,
 243                       "%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, offset);
 244         return;
 245     }
 246
 247     /* This means that a register write has affected the timer in a way that
 248      * requires a refresh of both tick_offset and the alarm.
 249      */
 250     s->tick_offset = stm32f2xx_ns_to_ticks(s, now) - timer_val;
 251     stm32f2xx_timer_set_alarm(s, now);
 252 }
 253
 254 static const MemoryRegionOps stm32f2xx_timer_ops = {
 255     .read = stm32f2xx_timer_read,
 256     .write = stm32f2xx_timer_write,
 257     .endianness = DEVICE_NATIVE_ENDIAN,
 258 };
 259
 260 static const VMStateDescription vmstate_stm32f2xx_timer = {
 261     .name = TYPE_STM32F2XX_TIMER,
 262     .version_id = 1,
 263     .minimum_version_id = 1,
 264     .fields = (VMStateField[]) {
 265         VMSTATE_INT64(tick_offset, STM32F2XXTimerState),
 266         VMSTATE_UINT32(tim_cr1, STM32F2XXTimerState),
 267         VMSTATE_UINT32(tim_cr2, STM32F2XXTimerState),
 268         VMSTATE_UINT32(tim_smcr, STM32F2XXTimerState),
 269         VMSTATE_UINT32(tim_dier, STM32F2XXTimerState),
 270         VMSTATE_UINT32(tim_sr, STM32F2XXTimerState),
 271         VMSTATE_UINT32(tim_egr, STM32F2XXTimerState),
 272         VMSTATE_UINT32(tim_ccmr1, STM32F2XXTimerState),
 273         VMSTATE_UINT32(tim_ccmr2, STM32F2XXTimerState),
 274         VMSTATE_UINT32(tim_ccer, STM32F2XXTimerState),
 275         VMSTATE_UINT32(tim_psc, STM32F2XXTimerState),
 276         VMSTATE_UINT32(tim_arr, STM32F2XXTimerState),
 277         VMSTATE_UINT32(tim_ccr1, STM32F2XXTimerState),
 278         VMSTATE_UINT32(tim_ccr2, STM32F2XXTimerState),
 279         VMSTATE_UINT32(tim_ccr3, STM32F2XXTimerState),
 280         VMSTATE_UINT32(tim_ccr4, STM32F2XXTimerState),
 281         VMSTATE_UINT32(tim_dcr, STM32F2XXTimerState),
 282         VMSTATE_UINT32(tim_dmar, STM32F2XXTimerState),
 283         VMSTATE_UINT32(tim_or, STM32F2XXTimerState),
 284         VMSTATE_END_OF_LIST()
 285     }
 286 };
 287
 288 static Property stm32f2xx_timer_properties[] = {
 289     DEFINE_PROP_UINT64("clock-frequency", struct STM32F2XXTimerState,
 290                        freq_hz, 1000000000),
 291     DEFINE_PROP_END_OF_LIST(),
 292 };
 293
 294 static void stm32f2xx_timer_init(Object *obj)
 295 {
 296     STM32F2XXTimerState *s = STM32F2XXTIMER(obj);
 297
 298     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->irq);
 299
 300     memory_region_init_io(&s->iomem, obj, &stm32f2xx_timer_ops, s,
 301                           "stm32f2xx_timer", 0x4000);
 302     sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->iomem);
 303
 304     s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, stm32f2xx_timer_interrupt, s);
 305 }
 306
 307 static void stm32f2xx_timer_class_init(ObjectClass *klass, void *data)
 308 {
 309     DeviceClass *dc = DEVICE_CLASS(klass);
 310
 311     dc->reset = stm32f2xx_timer_reset;
 312     dc->props = stm32f2xx_timer_properties;
 313     dc->vmsd = &vmstate_stm32f2xx_timer;
 314 }
 315
 316 static const TypeInfo stm32f2xx_timer_info = {
 317     .name          = TYPE_STM32F2XX_TIMER,
 318     .parent        = TYPE_SYS_BUS_DEVICE,
 319     .instance_size = sizeof(STM32F2XXTimerState),
 320     .instance_init = stm32f2xx_timer_init,
 321     .class_init    = stm32f2xx_timer_class_init,
 322 };
 323
 324 static void stm32f2xx_timer_register_types(void)
 325 {
 326     type_register_static(&stm32f2xx_timer_info);
 327 }
 328
 329 type_init(stm32f2xx_timer_register_types)