hw/timer/etraxfs_timer.c

   1 /*
   2  * QEMU ETRAX Timers
   3  *
   4  * Copyright (c) 2007 Edgar E. Iglesias, Axis Communications AB.
   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/sysbus.h"
  27 #include "sysemu/reset.h"
  28 #include "sysemu/runstate.h"
  29 #include "migration/vmstate.h"
  30 #include "qemu/module.h"
  31 #include "qemu/timer.h"
  32 #include "hw/irq.h"
  33 #include "hw/ptimer.h"
  34 #include "qom/object.h"
  35
  36 #define D(x)
  37
  38 #define RW_TMR0_DIV   0x00
  39 #define R_TMR0_DATA   0x04
  40 #define RW_TMR0_CTRL  0x08
  41 #define RW_TMR1_DIV   0x10
  42 #define R_TMR1_DATA   0x14
  43 #define RW_TMR1_CTRL  0x18
  44 #define R_TIME        0x38
  45 #define RW_WD_CTRL    0x40
  46 #define R_WD_STAT     0x44
  47 #define RW_INTR_MASK  0x48
  48 #define RW_ACK_INTR   0x4c
  49 #define R_INTR        0x50
  50 #define R_MASKED_INTR 0x54
  51
  52 #define TYPE_ETRAX_FS_TIMER "etraxfs-timer"
  53 typedef struct ETRAXTimerState ETRAXTimerState;
  54 DECLARE_INSTANCE_CHECKER(ETRAXTimerState, ETRAX_TIMER,
  55                          TYPE_ETRAX_FS_TIMER)
  56
  57 struct ETRAXTimerState {
  58     SysBusDevice parent_obj;
  59
  60     MemoryRegion mmio;
  61     qemu_irq irq;
  62     qemu_irq nmi;
  63
  64     ptimer_state *ptimer_t0;
  65     ptimer_state *ptimer_t1;
  66     ptimer_state *ptimer_wd;
  67
  68     uint32_t wd_hits;
  69
  70     /* Control registers.  */
  71     uint32_t rw_tmr0_div;
  72     uint32_t r_tmr0_data;
  73     uint32_t rw_tmr0_ctrl;
  74
  75     uint32_t rw_tmr1_div;
  76     uint32_t r_tmr1_data;
  77     uint32_t rw_tmr1_ctrl;
  78
  79     uint32_t rw_wd_ctrl;
  80
  81     uint32_t rw_intr_mask;
  82     uint32_t rw_ack_intr;
  83     uint32_t r_intr;
  84     uint32_t r_masked_intr;
  85 };
  86
  87 static const VMStateDescription vmstate_etraxfs = {
  88     .name = "etraxfs",
  89     .version_id = 0,
  90     .minimum_version_id = 0,
  91     .fields = (VMStateField[]) {
  92         VMSTATE_PTIMER(ptimer_t0, ETRAXTimerState),
  93         VMSTATE_PTIMER(ptimer_t1, ETRAXTimerState),
  94         VMSTATE_PTIMER(ptimer_wd, ETRAXTimerState),
  95
  96         VMSTATE_UINT32(wd_hits, ETRAXTimerState),
  97
  98         VMSTATE_UINT32(rw_tmr0_div, ETRAXTimerState),
  99         VMSTATE_UINT32(r_tmr0_data, ETRAXTimerState),
 100         VMSTATE_UINT32(rw_tmr0_ctrl, ETRAXTimerState),
 101
 102         VMSTATE_UINT32(rw_tmr1_div, ETRAXTimerState),
 103         VMSTATE_UINT32(r_tmr1_data, ETRAXTimerState),
 104         VMSTATE_UINT32(rw_tmr1_ctrl, ETRAXTimerState),
 105
 106         VMSTATE_UINT32(rw_wd_ctrl, ETRAXTimerState),
 107
 108         VMSTATE_UINT32(rw_intr_mask, ETRAXTimerState),
 109         VMSTATE_UINT32(rw_ack_intr, ETRAXTimerState),
 110         VMSTATE_UINT32(r_intr, ETRAXTimerState),
 111         VMSTATE_UINT32(r_masked_intr, ETRAXTimerState),
 112
 113         VMSTATE_END_OF_LIST()
 114     }
 115 };
 116
 117 static uint64_t
 118 timer_read(void *opaque, hwaddr addr, unsigned int size)
 119 {
 120     ETRAXTimerState *t = opaque;
 121     uint32_t r = 0;
 122
 123     switch (addr) {
 124     case R_TMR0_DATA:
 125         r = ptimer_get_count(t->ptimer_t0);
 126         break;
 127     case R_TMR1_DATA:
 128         r = ptimer_get_count(t->ptimer_t1);
 129         break;
 130     case R_TIME:
 131         r = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) / 10;
 132         break;
 133     case RW_INTR_MASK:
 134         r = t->rw_intr_mask;
 135         break;
 136     case R_MASKED_INTR:
 137         r = t->r_intr & t->rw_intr_mask;
 138         break;
 139     default:
 140         D(printf ("%s %x\n", __func__, addr));
 141         break;
 142     }
 143     return r;
 144 }
 145
 146 static void update_ctrl(ETRAXTimerState *t, int tnum)
 147 {
 148     unsigned int op;
 149     unsigned int freq;
 150     unsigned int freq_hz;
 151     unsigned int div;
 152     uint32_t ctrl;
 153
 154     ptimer_state *timer;
 155
 156     if (tnum == 0) {
 157         ctrl = t->rw_tmr0_ctrl;
 158         div = t->rw_tmr0_div;
 159         timer = t->ptimer_t0;
 160     } else {
 161         ctrl = t->rw_tmr1_ctrl;
 162         div = t->rw_tmr1_div;
 163         timer = t->ptimer_t1;
 164     }
 165
 166
 167     op = ctrl & 3;
 168     freq = ctrl >> 2;
 169     freq_hz = 32000000;
 170
 171     switch (freq)
 172     {
 173     case 0:
 174     case 1:
 175         D(printf ("extern or disabled timer clock?\n"));
 176         break;
 177     case 4: freq_hz =  29493000; break;
 178     case 5: freq_hz =  32000000; break;
 179     case 6: freq_hz =  32768000; break;
 180     case 7: freq_hz = 100000000; break;
 181     default:
 182         abort();
 183         break;
 184     }
 185
 186     D(printf ("freq_hz=%d div=%d\n", freq_hz, div));
 187     ptimer_transaction_begin(timer);
 188     ptimer_set_freq(timer, freq_hz);
 189     ptimer_set_limit(timer, div, 0);
 190
 191     switch (op)
 192     {
 193         case 0:
 194             /* Load.  */
 195             ptimer_set_limit(timer, div, 1);
 196             break;
 197         case 1:
 198             /* Hold.  */
 199             ptimer_stop(timer);
 200             break;
 201         case 2:
 202             /* Run.  */
 203             ptimer_run(timer, 0);
 204             break;
 205         default:
 206             abort();
 207             break;
 208     }
 209     ptimer_transaction_commit(timer);
 210 }
 211
 212 static void timer_update_irq(ETRAXTimerState *t)
 213 {
 214     t->r_intr &= ~(t->rw_ack_intr);
 215     t->r_masked_intr = t->r_intr & t->rw_intr_mask;
 216
 217     D(printf("%s: masked_intr=%x\n", __func__, t->r_masked_intr));
 218     qemu_set_irq(t->irq, !!t->r_masked_intr);
 219 }
 220
 221 static void timer0_hit(void *opaque)
 222 {
 223     ETRAXTimerState *t = opaque;
 224     t->r_intr |= 1;
 225     timer_update_irq(t);
 226 }
 227
 228 static void timer1_hit(void *opaque)
 229 {
 230     ETRAXTimerState *t = opaque;
 231     t->r_intr |= 2;
 232     timer_update_irq(t);
 233 }
 234
 235 static void watchdog_hit(void *opaque)
 236 {
 237     ETRAXTimerState *t = opaque;
 238     if (t->wd_hits == 0) {
 239         /* real hw gives a single tick before resetting but we are
 240            a bit friendlier to compensate for our slower execution.  */
 241         ptimer_set_count(t->ptimer_wd, 10);
 242         ptimer_run(t->ptimer_wd, 1);
 243         qemu_irq_raise(t->nmi);
 244     }
 245     else
 246         qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
 247
 248     t->wd_hits++;
 249 }
 250
 251 static inline void timer_watchdog_update(ETRAXTimerState *t, uint32_t value)
 252 {
 253     unsigned int wd_en = t->rw_wd_ctrl & (1 << 8);
 254     unsigned int wd_key = t->rw_wd_ctrl >> 9;
 255     unsigned int wd_cnt = t->rw_wd_ctrl & 511;
 256     unsigned int new_key = value >> 9 & ((1 << 7) - 1);
 257     unsigned int new_cmd = (value >> 8) & 1;
 258
 259     /* If the watchdog is enabled, they written key must match the
 260        complement of the previous.  */
 261     wd_key = ~wd_key & ((1 << 7) - 1);
 262
 263     if (wd_en && wd_key != new_key)
 264         return;
 265
 266     D(printf("en=%d new_key=%x oldkey=%x cmd=%d cnt=%d\n",
 267          wd_en, new_key, wd_key, new_cmd, wd_cnt));
 268
 269     if (t->wd_hits)
 270         qemu_irq_lower(t->nmi);
 271
 272     t->wd_hits = 0;
 273
 274     ptimer_transaction_begin(t->ptimer_wd);
 275     ptimer_set_freq(t->ptimer_wd, 760);
 276     if (wd_cnt == 0)
 277         wd_cnt = 256;
 278     ptimer_set_count(t->ptimer_wd, wd_cnt);
 279     if (new_cmd)
 280         ptimer_run(t->ptimer_wd, 1);
 281     else
 282         ptimer_stop(t->ptimer_wd);
 283
 284     t->rw_wd_ctrl = value;
 285     ptimer_transaction_commit(t->ptimer_wd);
 286 }
 287
 288 static void
 289 timer_write(void *opaque, hwaddr addr,
 290             uint64_t val64, unsigned int size)
 291 {
 292     ETRAXTimerState *t = opaque;
 293     uint32_t value = val64;
 294
 295     switch (addr)
 296     {
 297         case RW_TMR0_DIV:
 298             t->rw_tmr0_div = value;
 299             break;
 300         case RW_TMR0_CTRL:
 301             D(printf ("RW_TMR0_CTRL=%x\n", value));
 302             t->rw_tmr0_ctrl = value;
 303             update_ctrl(t, 0);
 304             break;
 305         case RW_TMR1_DIV:
 306             t->rw_tmr1_div = value;
 307             break;
 308         case RW_TMR1_CTRL:
 309             D(printf ("RW_TMR1_CTRL=%x\n", value));
 310             t->rw_tmr1_ctrl = value;
 311             update_ctrl(t, 1);
 312             break;
 313         case RW_INTR_MASK:
 314             D(printf ("RW_INTR_MASK=%x\n", value));
 315             t->rw_intr_mask = value;
 316             timer_update_irq(t);
 317             break;
 318         case RW_WD_CTRL:
 319             timer_watchdog_update(t, value);
 320             break;
 321         case RW_ACK_INTR:
 322             t->rw_ack_intr = value;
 323             timer_update_irq(t);
 324             t->rw_ack_intr = 0;
 325             break;
 326         default:
 327             printf("%s " HWADDR_FMT_plx " %x\n", __func__, addr, value);
 328             break;
 329     }
 330 }
 331
 332 static const MemoryRegionOps timer_ops = {
 333     .read = timer_read,
 334     .write = timer_write,
 335     .endianness = DEVICE_LITTLE_ENDIAN,
 336     .valid = {
 337         .min_access_size = 4,
 338         .max_access_size = 4
 339     }
 340 };
 341
 342 static void etraxfs_timer_reset_enter(Object *obj, ResetType type)
 343 {
 344     ETRAXTimerState *t = ETRAX_TIMER(obj);
 345
 346     ptimer_transaction_begin(t->ptimer_t0);
 347     ptimer_stop(t->ptimer_t0);
 348     ptimer_transaction_commit(t->ptimer_t0);
 349     ptimer_transaction_begin(t->ptimer_t1);
 350     ptimer_stop(t->ptimer_t1);
 351     ptimer_transaction_commit(t->ptimer_t1);
 352     ptimer_transaction_begin(t->ptimer_wd);
 353     ptimer_stop(t->ptimer_wd);
 354     ptimer_transaction_commit(t->ptimer_wd);
 355     t->rw_wd_ctrl = 0;
 356     t->r_intr = 0;
 357     t->rw_intr_mask = 0;
 358 }
 359
 360 static void etraxfs_timer_reset_hold(Object *obj)
 361 {
 362     ETRAXTimerState *t = ETRAX_TIMER(obj);
 363
 364     qemu_irq_lower(t->irq);
 365 }
 366
 367 static void etraxfs_timer_realize(DeviceState *dev, Error **errp)
 368 {
 369     ETRAXTimerState *t = ETRAX_TIMER(dev);
 370     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
 371
 372     t->ptimer_t0 = ptimer_init(timer0_hit, t, PTIMER_POLICY_LEGACY);
 373     t->ptimer_t1 = ptimer_init(timer1_hit, t, PTIMER_POLICY_LEGACY);
 374     t->ptimer_wd = ptimer_init(watchdog_hit, t, PTIMER_POLICY_LEGACY);
 375
 376     sysbus_init_irq(sbd, &t->irq);
 377     sysbus_init_irq(sbd, &t->nmi);
 378
 379     memory_region_init_io(&t->mmio, OBJECT(t), &timer_ops, t,
 380                           "etraxfs-timer", 0x5c);
 381     sysbus_init_mmio(sbd, &t->mmio);
 382 }
 383
 384 static void etraxfs_timer_class_init(ObjectClass *klass, void *data)
 385 {
 386     DeviceClass *dc = DEVICE_CLASS(klass);
 387     ResettableClass *rc = RESETTABLE_CLASS(klass);
 388
 389     dc->realize = etraxfs_timer_realize;
 390     dc->vmsd = &vmstate_etraxfs;
 391     rc->phases.enter = etraxfs_timer_reset_enter;
 392     rc->phases.hold = etraxfs_timer_reset_hold;
 393 }
 394
 395 static const TypeInfo etraxfs_timer_info = {
 396     .name          = TYPE_ETRAX_FS_TIMER,
 397     .parent        = TYPE_SYS_BUS_DEVICE,
 398     .instance_size = sizeof(ETRAXTimerState),
 399     .class_init    = etraxfs_timer_class_init,
 400 };
 401
 402 static void etraxfs_timer_register_types(void)
 403 {
 404     type_register_static(&etraxfs_timer_info);
 405 }
 406
 407 type_init(etraxfs_timer_register_types)