hw/timer/mss-timer.c

   1 /*
   2  * Block model of System timer present in
   3  * Microsemi's SmartFusion2 and SmartFusion SoCs.
   4  *
   5  * Copyright (c) 2017 Subbaraya Sundeep <sundeep.lkml@gmail.com>.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  23  * THE SOFTWARE.
  24  */
  25
  26 #include "qemu/osdep.h"
  27 #include "qemu/module.h"
  28 #include "qemu/log.h"
  29 #include "hw/irq.h"
  30 #include "hw/qdev-properties.h"
  31 #include "hw/timer/mss-timer.h"
  32 #include "migration/vmstate.h"
  33
  34 #ifndef MSS_TIMER_ERR_DEBUG
  35 #define MSS_TIMER_ERR_DEBUG  0
  36 #endif
  37
  38 #define DB_PRINT_L(lvl, fmt, args...) do { \
  39     if (MSS_TIMER_ERR_DEBUG >= lvl) { \
  40         qemu_log("%s: " fmt "\n", __func__, ## args); \
  41     } \
  42 } while (0)
  43
  44 #define DB_PRINT(fmt, args...) DB_PRINT_L(1, fmt, ## args)
  45
  46 #define R_TIM_VAL         0
  47 #define R_TIM_LOADVAL     1
  48 #define R_TIM_BGLOADVAL   2
  49 #define R_TIM_CTRL        3
  50 #define R_TIM_RIS         4
  51 #define R_TIM_MIS         5
  52
  53 #define TIMER_CTRL_ENBL     (1 << 0)
  54 #define TIMER_CTRL_ONESHOT  (1 << 1)
  55 #define TIMER_CTRL_INTR     (1 << 2)
  56 #define TIMER_RIS_ACK       (1 << 0)
  57 #define TIMER_RST_CLR       (1 << 6)
  58 #define TIMER_MODE          (1 << 0)
  59
  60 static void timer_update_irq(struct Msf2Timer *st)
  61 {
  62     bool isr, ier;
  63
  64     isr = !!(st->regs[R_TIM_RIS] & TIMER_RIS_ACK);
  65     ier = !!(st->regs[R_TIM_CTRL] & TIMER_CTRL_INTR);
  66     qemu_set_irq(st->irq, (ier && isr));
  67 }
  68
  69 /* Must be called from within a ptimer_transaction_begin/commit block */
  70 static void timer_update(struct Msf2Timer *st)
  71 {
  72     uint64_t count;
  73
  74     if (!(st->regs[R_TIM_CTRL] & TIMER_CTRL_ENBL)) {
  75         ptimer_stop(st->ptimer);
  76         return;
  77     }
  78
  79     count = st->regs[R_TIM_LOADVAL];
  80     ptimer_set_limit(st->ptimer, count, 1);
  81     ptimer_run(st->ptimer, 1);
  82 }
  83
  84 static uint64_t
  85 timer_read(void *opaque, hwaddr offset, unsigned int size)
  86 {
  87     MSSTimerState *t = opaque;
  88     hwaddr addr;
  89     struct Msf2Timer *st;
  90     uint32_t ret = 0;
  91     int timer = 0;
  92     int isr;
  93     int ier;
  94
  95     addr = offset >> 2;
  96     /*
  97      * Two independent timers has same base address.
  98      * Based on address passed figure out which timer is being used.
  99      */
 100     if ((addr >= R_TIM1_MAX) && (addr < NUM_TIMERS * R_TIM1_MAX)) {
 101         timer = 1;
 102         addr -= R_TIM1_MAX;
 103     }
 104
 105     st = &t->timers[timer];
 106
 107     switch (addr) {
 108     case R_TIM_VAL:
 109         ret = ptimer_get_count(st->ptimer);
 110         break;
 111
 112     case R_TIM_MIS:
 113         isr = !!(st->regs[R_TIM_RIS] & TIMER_RIS_ACK);
 114         ier = !!(st->regs[R_TIM_CTRL] & TIMER_CTRL_INTR);
 115         ret = ier & isr;
 116         break;
 117
 118     default:
 119         if (addr < R_TIM1_MAX) {
 120             ret = st->regs[addr];
 121         } else {
 122             qemu_log_mask(LOG_GUEST_ERROR,
 123                         TYPE_MSS_TIMER": 64-bit mode not supported\n");
 124             return ret;
 125         }
 126         break;
 127     }
 128
 129     DB_PRINT("timer=%d 0x%" HWADDR_PRIx "=0x%" PRIx32, timer, offset,
 130             ret);
 131     return ret;
 132 }
 133
 134 static void
 135 timer_write(void *opaque, hwaddr offset,
 136             uint64_t val64, unsigned int size)
 137 {
 138     MSSTimerState *t = opaque;
 139     hwaddr addr;
 140     struct Msf2Timer *st;
 141     int timer = 0;
 142     uint32_t value = val64;
 143
 144     addr = offset >> 2;
 145     /*
 146      * Two independent timers has same base address.
 147      * Based on addr passed figure out which timer is being used.
 148      */
 149     if ((addr >= R_TIM1_MAX) && (addr < NUM_TIMERS * R_TIM1_MAX)) {
 150         timer = 1;
 151         addr -= R_TIM1_MAX;
 152     }
 153
 154     st = &t->timers[timer];
 155
 156     DB_PRINT("addr=0x%" HWADDR_PRIx " val=0x%" PRIx32 " (timer=%d)", offset,
 157             value, timer);
 158
 159     switch (addr) {
 160     case R_TIM_CTRL:
 161         st->regs[R_TIM_CTRL] = value;
 162         ptimer_transaction_begin(st->ptimer);
 163         timer_update(st);
 164         ptimer_transaction_commit(st->ptimer);
 165         break;
 166
 167     case R_TIM_RIS:
 168         if (value & TIMER_RIS_ACK) {
 169             st->regs[R_TIM_RIS] &= ~TIMER_RIS_ACK;
 170         }
 171         break;
 172
 173     case R_TIM_LOADVAL:
 174         st->regs[R_TIM_LOADVAL] = value;
 175         if (st->regs[R_TIM_CTRL] & TIMER_CTRL_ENBL) {
 176             ptimer_transaction_begin(st->ptimer);
 177             timer_update(st);
 178             ptimer_transaction_commit(st->ptimer);
 179         }
 180         break;
 181
 182     case R_TIM_BGLOADVAL:
 183         st->regs[R_TIM_BGLOADVAL] = value;
 184         st->regs[R_TIM_LOADVAL] = value;
 185         break;
 186
 187     case R_TIM_VAL:
 188     case R_TIM_MIS:
 189         break;
 190
 191     default:
 192         if (addr < R_TIM1_MAX) {
 193             st->regs[addr] = value;
 194         } else {
 195             qemu_log_mask(LOG_GUEST_ERROR,
 196                         TYPE_MSS_TIMER": 64-bit mode not supported\n");
 197             return;
 198         }
 199         break;
 200     }
 201     timer_update_irq(st);
 202 }
 203
 204 static const MemoryRegionOps timer_ops = {
 205     .read = timer_read,
 206     .write = timer_write,
 207     .endianness = DEVICE_NATIVE_ENDIAN,
 208     .valid = {
 209         .min_access_size = 1,
 210         .max_access_size = 4
 211     }
 212 };
 213
 214 static void timer_hit(void *opaque)
 215 {
 216     struct Msf2Timer *st = opaque;
 217
 218     st->regs[R_TIM_RIS] |= TIMER_RIS_ACK;
 219
 220     if (!(st->regs[R_TIM_CTRL] & TIMER_CTRL_ONESHOT)) {
 221         timer_update(st);
 222     }
 223     timer_update_irq(st);
 224 }
 225
 226 static void mss_timer_init(Object *obj)
 227 {
 228     MSSTimerState *t = MSS_TIMER(obj);
 229     int i;
 230
 231     /* Init all the ptimers.  */
 232     for (i = 0; i < NUM_TIMERS; i++) {
 233         struct Msf2Timer *st = &t->timers[i];
 234
 235         st->ptimer = ptimer_init(timer_hit, st, PTIMER_POLICY_LEGACY);
 236         ptimer_transaction_begin(st->ptimer);
 237         ptimer_set_freq(st->ptimer, t->freq_hz);
 238         ptimer_transaction_commit(st->ptimer);
 239         sysbus_init_irq(SYS_BUS_DEVICE(obj), &st->irq);
 240     }
 241
 242     memory_region_init_io(&t->mmio, OBJECT(t), &timer_ops, t, TYPE_MSS_TIMER,
 243                           NUM_TIMERS * R_TIM1_MAX * 4);
 244     sysbus_init_mmio(SYS_BUS_DEVICE(obj), &t->mmio);
 245 }
 246
 247 static void mss_timer_finalize(Object *obj)
 248 {
 249     MSSTimerState *t = MSS_TIMER(obj);
 250     int i;
 251
 252     for (i = 0; i < NUM_TIMERS; i++) {
 253         struct Msf2Timer *st = &t->timers[i];
 254
 255         ptimer_free(st->ptimer);
 256     }
 257 }
 258
 259 static const VMStateDescription vmstate_timers = {
 260     .name = "mss-timer-block",
 261     .version_id = 1,
 262     .minimum_version_id = 1,
 263     .fields = (VMStateField[]) {
 264         VMSTATE_PTIMER(ptimer, struct Msf2Timer),
 265         VMSTATE_UINT32_ARRAY(regs, struct Msf2Timer, R_TIM1_MAX),
 266         VMSTATE_END_OF_LIST()
 267     }
 268 };
 269
 270 static const VMStateDescription vmstate_mss_timer = {
 271     .name = TYPE_MSS_TIMER,
 272     .version_id = 1,
 273     .minimum_version_id = 1,
 274     .fields = (VMStateField[]) {
 275         VMSTATE_UINT32(freq_hz, MSSTimerState),
 276         VMSTATE_STRUCT_ARRAY(timers, MSSTimerState, NUM_TIMERS, 0,
 277                 vmstate_timers, struct Msf2Timer),
 278         VMSTATE_END_OF_LIST()
 279     }
 280 };
 281
 282 static Property mss_timer_properties[] = {
 283     /* Libero GUI shows 100Mhz as default for clocks */
 284     DEFINE_PROP_UINT32("clock-frequency", MSSTimerState, freq_hz,
 285                       100 * 1000000),
 286     DEFINE_PROP_END_OF_LIST(),
 287 };
 288
 289 static void mss_timer_class_init(ObjectClass *klass, void *data)
 290 {
 291     DeviceClass *dc = DEVICE_CLASS(klass);
 292
 293     device_class_set_props(dc, mss_timer_properties);
 294     dc->vmsd = &vmstate_mss_timer;
 295 }
 296
 297 static const TypeInfo mss_timer_info = {
 298     .name          = TYPE_MSS_TIMER,
 299     .parent        = TYPE_SYS_BUS_DEVICE,
 300     .instance_size = sizeof(MSSTimerState),
 301     .instance_init = mss_timer_init,
 302     .instance_finalize = mss_timer_finalize,
 303     .class_init    = mss_timer_class_init,
 304 };
 305
 306 static void mss_timer_register_types(void)
 307 {
 308     type_register_static(&mss_timer_info);
 309 }
 310
 311 type_init(mss_timer_register_types)