hw/timer/slavio_timer.c

   1 /*
   2  * QEMU Sparc SLAVIO timer controller emulation
   3  *
   4  * Copyright (c) 2003-2005 Fabrice Bellard
   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 "qemu/timer.h"
  27 #include "hw/irq.h"
  28 #include "hw/ptimer.h"
  29 #include "hw/qdev-properties.h"
  30 #include "hw/sysbus.h"
  31 #include "migration/vmstate.h"
  32 #include "trace.h"
  33 #include "qemu/module.h"
  34 #include "qom/object.h"
  35
  36 /*
  37  * Registers of hardware timer in sun4m.
  38  *
  39  * This is the timer/counter part of chip STP2001 (Slave I/O), also
  40  * produced as NCR89C105. See
  41  * http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR89C105.txt
  42  *
  43  * The 31-bit counter is incremented every 500ns by bit 9. Bits 8..0
  44  * are zero. Bit 31 is 1 when count has been reached.
  45  *
  46  * Per-CPU timers interrupt local CPU, system timer uses normal
  47  * interrupt routing.
  48  *
  49  */
  50
  51 #define MAX_CPUS 16
  52
  53 typedef struct CPUTimerState {
  54     qemu_irq irq;
  55     ptimer_state *timer;
  56     uint32_t count, counthigh, reached;
  57     /* processor only */
  58     uint32_t run;
  59     uint64_t limit;
  60 } CPUTimerState;
  61
  62 #define TYPE_SLAVIO_TIMER "slavio_timer"
  63 OBJECT_DECLARE_SIMPLE_TYPE(SLAVIO_TIMERState, SLAVIO_TIMER)
  64
  65 struct SLAVIO_TIMERState {
  66     SysBusDevice parent_obj;
  67
  68     uint32_t num_cpus;
  69     uint32_t cputimer_mode;
  70     CPUTimerState cputimer[MAX_CPUS + 1];
  71 };
  72
  73 typedef struct TimerContext {
  74     MemoryRegion iomem;
  75     SLAVIO_TIMERState *s;
  76     unsigned int timer_index; /* 0 for system, 1 ... MAX_CPUS for CPU timers */
  77 } TimerContext;
  78
  79 #define SYS_TIMER_SIZE 0x14
  80 #define CPU_TIMER_SIZE 0x10
  81
  82 #define TIMER_LIMIT         0
  83 #define TIMER_COUNTER       1
  84 #define TIMER_COUNTER_NORST 2
  85 #define TIMER_STATUS        3
  86 #define TIMER_MODE          4
  87
  88 #define TIMER_COUNT_MASK32 0xfffffe00
  89 #define TIMER_LIMIT_MASK32 0x7fffffff
  90 #define TIMER_MAX_COUNT64  0x7ffffffffffffe00ULL
  91 #define TIMER_MAX_COUNT32  0x7ffffe00ULL
  92 #define TIMER_REACHED      0x80000000
  93 #define TIMER_PERIOD       500ULL // 500ns
  94 #define LIMIT_TO_PERIODS(l) (((l) >> 9) - 1)
  95 #define PERIODS_TO_LIMIT(l) (((l) + 1) << 9)
  96
  97 static int slavio_timer_is_user(TimerContext *tc)
  98 {
  99     SLAVIO_TIMERState *s = tc->s;
 100     unsigned int timer_index = tc->timer_index;
 101
 102     return timer_index != 0 && (s->cputimer_mode & (1 << (timer_index - 1)));
 103 }
 104
 105 // Update count, set irq, update expire_time
 106 // Convert from ptimer countdown units
 107 static void slavio_timer_get_out(CPUTimerState *t)
 108 {
 109     uint64_t count, limit;
 110
 111     if (t->limit == 0) { /* free-run system or processor counter */
 112         limit = TIMER_MAX_COUNT32;
 113     } else {
 114         limit = t->limit;
 115     }
 116     count = limit - PERIODS_TO_LIMIT(ptimer_get_count(t->timer));
 117
 118     trace_slavio_timer_get_out(t->limit, t->counthigh, t->count);
 119     t->count = count & TIMER_COUNT_MASK32;
 120     t->counthigh = count >> 32;
 121 }
 122
 123 // timer callback
 124 static void slavio_timer_irq(void *opaque)
 125 {
 126     TimerContext *tc = opaque;
 127     SLAVIO_TIMERState *s = tc->s;
 128     CPUTimerState *t = &s->cputimer[tc->timer_index];
 129
 130     slavio_timer_get_out(t);
 131     trace_slavio_timer_irq(t->counthigh, t->count);
 132     /* if limit is 0 (free-run), there will be no match */
 133     if (t->limit != 0) {
 134         t->reached = TIMER_REACHED;
 135     }
 136     /* there is no interrupt if user timer or free-run */
 137     if (!slavio_timer_is_user(tc) && t->limit != 0) {
 138         qemu_irq_raise(t->irq);
 139     }
 140 }
 141
 142 static uint64_t slavio_timer_mem_readl(void *opaque, hwaddr addr,
 143                                        unsigned size)
 144 {
 145     TimerContext *tc = opaque;
 146     SLAVIO_TIMERState *s = tc->s;
 147     uint32_t saddr, ret;
 148     unsigned int timer_index = tc->timer_index;
 149     CPUTimerState *t = &s->cputimer[timer_index];
 150
 151     saddr = addr >> 2;
 152     switch (saddr) {
 153     case TIMER_LIMIT:
 154         // read limit (system counter mode) or read most signifying
 155         // part of counter (user mode)
 156         if (slavio_timer_is_user(tc)) {
 157             // read user timer MSW
 158             slavio_timer_get_out(t);
 159             ret = t->counthigh | t->reached;
 160         } else {
 161             // read limit
 162             // clear irq
 163             qemu_irq_lower(t->irq);
 164             t->reached = 0;
 165             ret = t->limit & TIMER_LIMIT_MASK32;
 166         }
 167         break;
 168     case TIMER_COUNTER:
 169         // read counter and reached bit (system mode) or read lsbits
 170         // of counter (user mode)
 171         slavio_timer_get_out(t);
 172         if (slavio_timer_is_user(tc)) { // read user timer LSW
 173             ret = t->count & TIMER_MAX_COUNT64;
 174         } else { // read limit
 175             ret = (t->count & TIMER_MAX_COUNT32) |
 176                 t->reached;
 177         }
 178         break;
 179     case TIMER_STATUS:
 180         // only available in processor counter/timer
 181         // read start/stop status
 182         if (timer_index > 0) {
 183             ret = t->run;
 184         } else {
 185             ret = 0;
 186         }
 187         break;
 188     case TIMER_MODE:
 189         // only available in system counter
 190         // read user/system mode
 191         ret = s->cputimer_mode;
 192         break;
 193     default:
 194         trace_slavio_timer_mem_readl_invalid(addr);
 195         ret = 0;
 196         break;
 197     }
 198     trace_slavio_timer_mem_readl(addr, ret);
 199     return ret;
 200 }
 201
 202 static void slavio_timer_mem_writel(void *opaque, hwaddr addr,
 203                                     uint64_t val, unsigned size)
 204 {
 205     TimerContext *tc = opaque;
 206     SLAVIO_TIMERState *s = tc->s;
 207     uint32_t saddr;
 208     unsigned int timer_index = tc->timer_index;
 209     CPUTimerState *t = &s->cputimer[timer_index];
 210
 211     trace_slavio_timer_mem_writel(addr, val);
 212     saddr = addr >> 2;
 213     switch (saddr) {
 214     case TIMER_LIMIT:
 215         ptimer_transaction_begin(t->timer);
 216         if (slavio_timer_is_user(tc)) {
 217             uint64_t count;
 218
 219             // set user counter MSW, reset counter
 220             t->limit = TIMER_MAX_COUNT64;
 221             t->counthigh = val & (TIMER_MAX_COUNT64 >> 32);
 222             t->reached = 0;
 223             count = ((uint64_t)t->counthigh << 32) | t->count;
 224             trace_slavio_timer_mem_writel_limit(timer_index, count);
 225             ptimer_set_count(t->timer, LIMIT_TO_PERIODS(t->limit - count));
 226         } else {
 227             // set limit, reset counter
 228             qemu_irq_lower(t->irq);
 229             t->limit = val & TIMER_MAX_COUNT32;
 230             if (t->limit == 0) { /* free-run */
 231                 ptimer_set_limit(t->timer,
 232                                  LIMIT_TO_PERIODS(TIMER_MAX_COUNT32), 1);
 233             } else {
 234                 ptimer_set_limit(t->timer, LIMIT_TO_PERIODS(t->limit), 1);
 235             }
 236         }
 237         ptimer_transaction_commit(t->timer);
 238         break;
 239     case TIMER_COUNTER:
 240         if (slavio_timer_is_user(tc)) {
 241             uint64_t count;
 242
 243             // set user counter LSW, reset counter
 244             t->limit = TIMER_MAX_COUNT64;
 245             t->count = val & TIMER_MAX_COUNT64;
 246             t->reached = 0;
 247             count = ((uint64_t)t->counthigh) << 32 | t->count;
 248             trace_slavio_timer_mem_writel_limit(timer_index, count);
 249             ptimer_transaction_begin(t->timer);
 250             ptimer_set_count(t->timer, LIMIT_TO_PERIODS(t->limit - count));
 251             ptimer_transaction_commit(t->timer);
 252         } else {
 253             trace_slavio_timer_mem_writel_counter_invalid();
 254         }
 255         break;
 256     case TIMER_COUNTER_NORST:
 257         // set limit without resetting counter
 258         t->limit = val & TIMER_MAX_COUNT32;
 259         ptimer_transaction_begin(t->timer);
 260         if (t->limit == 0) { /* free-run */
 261             ptimer_set_limit(t->timer, LIMIT_TO_PERIODS(TIMER_MAX_COUNT32), 0);
 262         } else {
 263             ptimer_set_limit(t->timer, LIMIT_TO_PERIODS(t->limit), 0);
 264         }
 265         ptimer_transaction_commit(t->timer);
 266         break;
 267     case TIMER_STATUS:
 268         ptimer_transaction_begin(t->timer);
 269         if (slavio_timer_is_user(tc)) {
 270             // start/stop user counter
 271             if (val & 1) {
 272                 trace_slavio_timer_mem_writel_status_start(timer_index);
 273                 ptimer_run(t->timer, 0);
 274             } else {
 275                 trace_slavio_timer_mem_writel_status_stop(timer_index);
 276                 ptimer_stop(t->timer);
 277             }
 278         }
 279         t->run = val & 1;
 280         ptimer_transaction_commit(t->timer);
 281         break;
 282     case TIMER_MODE:
 283         if (timer_index == 0) {
 284             unsigned int i;
 285
 286             for (i = 0; i < s->num_cpus; i++) {
 287                 unsigned int processor = 1 << i;
 288                 CPUTimerState *curr_timer = &s->cputimer[i + 1];
 289
 290                 ptimer_transaction_begin(curr_timer->timer);
 291                 // check for a change in timer mode for this processor
 292                 if ((val & processor) != (s->cputimer_mode & processor)) {
 293                     if (val & processor) { // counter -> user timer
 294                         qemu_irq_lower(curr_timer->irq);
 295                         // counters are always running
 296                         if (!curr_timer->run) {
 297                             ptimer_stop(curr_timer->timer);
 298                         }
 299                         // user timer limit is always the same
 300                         curr_timer->limit = TIMER_MAX_COUNT64;
 301                         ptimer_set_limit(curr_timer->timer,
 302                                          LIMIT_TO_PERIODS(curr_timer->limit),
 303                                          1);
 304                         // set this processors user timer bit in config
 305                         // register
 306                         s->cputimer_mode |= processor;
 307                         trace_slavio_timer_mem_writel_mode_user(timer_index);
 308                     } else { // user timer -> counter
 309                         // start the counter
 310                         ptimer_run(curr_timer->timer, 0);
 311                         // clear this processors user timer bit in config
 312                         // register
 313                         s->cputimer_mode &= ~processor;
 314                         trace_slavio_timer_mem_writel_mode_counter(timer_index);
 315                     }
 316                 }
 317                 ptimer_transaction_commit(curr_timer->timer);
 318             }
 319         } else {
 320             trace_slavio_timer_mem_writel_mode_invalid();
 321         }
 322         break;
 323     default:
 324         trace_slavio_timer_mem_writel_invalid(addr);
 325         break;
 326     }
 327 }
 328
 329 static const MemoryRegionOps slavio_timer_mem_ops = {
 330     .read = slavio_timer_mem_readl,
 331     .write = slavio_timer_mem_writel,
 332     .endianness = DEVICE_NATIVE_ENDIAN,
 333     .valid = {
 334         .min_access_size = 4,
 335         .max_access_size = 8,
 336     },
 337     .impl = {
 338         .min_access_size = 4,
 339         .max_access_size = 4,
 340     },
 341 };
 342
 343 static const VMStateDescription vmstate_timer = {
 344     .name ="timer",
 345     .version_id = 3,
 346     .minimum_version_id = 3,
 347     .fields = (VMStateField[]) {
 348         VMSTATE_UINT64(limit, CPUTimerState),
 349         VMSTATE_UINT32(count, CPUTimerState),
 350         VMSTATE_UINT32(counthigh, CPUTimerState),
 351         VMSTATE_UINT32(reached, CPUTimerState),
 352         VMSTATE_UINT32(run    , CPUTimerState),
 353         VMSTATE_PTIMER(timer, CPUTimerState),
 354         VMSTATE_END_OF_LIST()
 355     }
 356 };
 357
 358 static const VMStateDescription vmstate_slavio_timer = {
 359     .name ="slavio_timer",
 360     .version_id = 3,
 361     .minimum_version_id = 3,
 362     .fields = (VMStateField[]) {
 363         VMSTATE_STRUCT_ARRAY(cputimer, SLAVIO_TIMERState, MAX_CPUS + 1, 3,
 364                              vmstate_timer, CPUTimerState),
 365         VMSTATE_END_OF_LIST()
 366     }
 367 };
 368
 369 static void slavio_timer_reset(DeviceState *d)
 370 {
 371     SLAVIO_TIMERState *s = SLAVIO_TIMER(d);
 372     unsigned int i;
 373     CPUTimerState *curr_timer;
 374
 375     for (i = 0; i <= MAX_CPUS; i++) {
 376         curr_timer = &s->cputimer[i];
 377         curr_timer->limit = 0;
 378         curr_timer->count = 0;
 379         curr_timer->reached = 0;
 380         if (i <= s->num_cpus) {
 381             ptimer_transaction_begin(curr_timer->timer);
 382             ptimer_set_limit(curr_timer->timer,
 383                              LIMIT_TO_PERIODS(TIMER_MAX_COUNT32), 1);
 384             ptimer_run(curr_timer->timer, 0);
 385             curr_timer->run = 1;
 386             ptimer_transaction_commit(curr_timer->timer);
 387         }
 388     }
 389     s->cputimer_mode = 0;
 390 }
 391
 392 static void slavio_timer_init(Object *obj)
 393 {
 394     SLAVIO_TIMERState *s = SLAVIO_TIMER(obj);
 395     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
 396     unsigned int i;
 397     TimerContext *tc;
 398
 399     for (i = 0; i <= MAX_CPUS; i++) {
 400         uint64_t size;
 401         char timer_name[20];
 402
 403         tc = g_malloc0(sizeof(TimerContext));
 404         tc->s = s;
 405         tc->timer_index = i;
 406
 407         s->cputimer[i].timer = ptimer_init(slavio_timer_irq, tc,
 408                                            PTIMER_POLICY_DEFAULT);
 409         ptimer_transaction_begin(s->cputimer[i].timer);
 410         ptimer_set_period(s->cputimer[i].timer, TIMER_PERIOD);
 411         ptimer_transaction_commit(s->cputimer[i].timer);
 412
 413         size = i == 0 ? SYS_TIMER_SIZE : CPU_TIMER_SIZE;
 414         snprintf(timer_name, sizeof(timer_name), "timer-%i", i);
 415         memory_region_init_io(&tc->iomem, obj, &slavio_timer_mem_ops, tc,
 416                               timer_name, size);
 417         sysbus_init_mmio(dev, &tc->iomem);
 418
 419         sysbus_init_irq(dev, &s->cputimer[i].irq);
 420     }
 421 }
 422
 423 static Property slavio_timer_properties[] = {
 424     DEFINE_PROP_UINT32("num_cpus",  SLAVIO_TIMERState, num_cpus,  0),
 425     DEFINE_PROP_END_OF_LIST(),
 426 };
 427
 428 static void slavio_timer_class_init(ObjectClass *klass, void *data)
 429 {
 430     DeviceClass *dc = DEVICE_CLASS(klass);
 431
 432     dc->reset = slavio_timer_reset;
 433     dc->vmsd = &vmstate_slavio_timer;
 434     device_class_set_props(dc, slavio_timer_properties);
 435 }
 436
 437 static const TypeInfo slavio_timer_info = {
 438     .name          = TYPE_SLAVIO_TIMER,
 439     .parent        = TYPE_SYS_BUS_DEVICE,
 440     .instance_size = sizeof(SLAVIO_TIMERState),
 441     .instance_init = slavio_timer_init,
 442     .class_init    = slavio_timer_class_init,
 443 };
 444
 445 static void slavio_timer_register_types(void)
 446 {
 447     type_register_static(&slavio_timer_info);
 448 }
 449
 450 type_init(slavio_timer_register_types)