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