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