hw/timer/exynos4210_pwm.c

   1 /*
   2  * Samsung exynos4210 Pulse Width Modulation Timer
   3  *
   4  * Copyright (c) 2000 - 2011 Samsung Electronics Co., Ltd.
   5  * All rights reserved.
   6  *
   7  * Evgeny Voevodin <e.voevodin@samsung.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU General Public License as published by the
  11  * Free Software Foundation; either version 2 of the License, or (at your
  12  * option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  17  * See the GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, see <http://www.gnu.org/licenses/>.
  21  */
  22
  23 #include "hw/sysbus.h"
  24 #include "qemu/timer.h"
  25 #include "qemu-common.h"
  26 #include "qemu/main-loop.h"
  27 #include "hw/ptimer.h"
  28
  29 #include "hw/arm/exynos4210.h"
  30
  31 //#define DEBUG_PWM
  32
  33 #ifdef DEBUG_PWM
  34 #define DPRINTF(fmt, ...) \
  35         do { fprintf(stdout, "PWM: [%24s:%5d] " fmt, __func__, __LINE__, \
  36                 ## __VA_ARGS__); } while (0)
  37 #else
  38 #define DPRINTF(fmt, ...) do {} while (0)
  39 #endif
  40
  41 #define     EXYNOS4210_PWM_TIMERS_NUM      5
  42 #define     EXYNOS4210_PWM_REG_MEM_SIZE    0x50
  43
  44 #define     TCFG0        0x0000
  45 #define     TCFG1        0x0004
  46 #define     TCON         0x0008
  47 #define     TCNTB0       0x000C
  48 #define     TCMPB0       0x0010
  49 #define     TCNTO0       0x0014
  50 #define     TCNTB1       0x0018
  51 #define     TCMPB1       0x001C
  52 #define     TCNTO1       0x0020
  53 #define     TCNTB2       0x0024
  54 #define     TCMPB2       0x0028
  55 #define     TCNTO2       0x002C
  56 #define     TCNTB3       0x0030
  57 #define     TCMPB3       0x0034
  58 #define     TCNTO3       0x0038
  59 #define     TCNTB4       0x003C
  60 #define     TCNTO4       0x0040
  61 #define     TINT_CSTAT   0x0044
  62
  63 #define     TCNTB(x)    (0xC * (x))
  64 #define     TCMPB(x)    (0xC * (x) + 1)
  65 #define     TCNTO(x)    (0xC * (x) + 2)
  66
  67 #define GET_PRESCALER(reg, x) (((reg) & (0xFF << (8 * (x)))) >> 8 * (x))
  68 #define GET_DIVIDER(reg, x) (1 << (((reg) & (0xF << (4 * (x)))) >> (4 * (x))))
  69
  70 /*
  71  * Attention! Timer4 doesn't have OUTPUT_INVERTER,
  72  * so Auto Reload bit is not accessible by macros!
  73  */
  74 #define     TCON_TIMER_BASE(x)          (((x) ? 1 : 0) * 4 + 4 * (x))
  75 #define     TCON_TIMER_START(x)         (1 << (TCON_TIMER_BASE(x) + 0))
  76 #define     TCON_TIMER_MANUAL_UPD(x)    (1 << (TCON_TIMER_BASE(x) + 1))
  77 #define     TCON_TIMER_OUTPUT_INV(x)    (1 << (TCON_TIMER_BASE(x) + 2))
  78 #define     TCON_TIMER_AUTO_RELOAD(x)   (1 << (TCON_TIMER_BASE(x) + 3))
  79 #define     TCON_TIMER4_AUTO_RELOAD     (1 << 22)
  80
  81 #define     TINT_CSTAT_STATUS(x)        (1 << (5 + (x)))
  82 #define     TINT_CSTAT_ENABLE(x)        (1 << (x))
  83
  84 /* timer struct */
  85 typedef struct {
  86     uint32_t    id;             /* timer id */
  87     qemu_irq    irq;            /* local timer irq */
  88     uint32_t    freq;           /* timer frequency */
  89
  90     /* use ptimer.c to represent count down timer */
  91     ptimer_state *ptimer;       /* timer  */
  92
  93     /* registers */
  94     uint32_t    reg_tcntb;      /* counter register buffer */
  95     uint32_t    reg_tcmpb;      /* compare register buffer */
  96
  97     struct Exynos4210PWMState *parent;
  98
  99 } Exynos4210PWM;
 100
 101 #define TYPE_EXYNOS4210_PWM "exynos4210.pwm"
 102 #define EXYNOS4210_PWM(obj) \
 103     OBJECT_CHECK(Exynos4210PWMState, (obj), TYPE_EXYNOS4210_PWM)
 104
 105 typedef struct Exynos4210PWMState {
 106     SysBusDevice parent_obj;
 107
 108     MemoryRegion iomem;
 109
 110     uint32_t    reg_tcfg[2];
 111     uint32_t    reg_tcon;
 112     uint32_t    reg_tint_cstat;
 113
 114     Exynos4210PWM timer[EXYNOS4210_PWM_TIMERS_NUM];
 115
 116 } Exynos4210PWMState;
 117
 118 /*** VMState ***/
 119 static const VMStateDescription vmstate_exynos4210_pwm = {
 120     .name = "exynos4210.pwm.pwm",
 121     .version_id = 1,
 122     .minimum_version_id = 1,
 123     .minimum_version_id_old = 1,
 124     .fields = (VMStateField[]) {
 125         VMSTATE_UINT32(id, Exynos4210PWM),
 126         VMSTATE_UINT32(freq, Exynos4210PWM),
 127         VMSTATE_PTIMER(ptimer, Exynos4210PWM),
 128         VMSTATE_UINT32(reg_tcntb, Exynos4210PWM),
 129         VMSTATE_UINT32(reg_tcmpb, Exynos4210PWM),
 130         VMSTATE_END_OF_LIST()
 131     }
 132 };
 133
 134 static const VMStateDescription vmstate_exynos4210_pwm_state = {
 135     .name = "exynos4210.pwm",
 136     .version_id = 1,
 137     .minimum_version_id = 1,
 138     .minimum_version_id_old = 1,
 139     .fields = (VMStateField[]) {
 140         VMSTATE_UINT32_ARRAY(reg_tcfg, Exynos4210PWMState, 2),
 141         VMSTATE_UINT32(reg_tcon, Exynos4210PWMState),
 142         VMSTATE_UINT32(reg_tint_cstat, Exynos4210PWMState),
 143         VMSTATE_STRUCT_ARRAY(timer, Exynos4210PWMState,
 144             EXYNOS4210_PWM_TIMERS_NUM, 0,
 145         vmstate_exynos4210_pwm, Exynos4210PWM),
 146         VMSTATE_END_OF_LIST()
 147     }
 148 };
 149
 150 /*
 151  * PWM update frequency
 152  */
 153 static void exynos4210_pwm_update_freq(Exynos4210PWMState *s, uint32_t id)
 154 {
 155     uint32_t freq;
 156     freq = s->timer[id].freq;
 157     if (id > 1) {
 158         s->timer[id].freq = 24000000 /
 159         ((GET_PRESCALER(s->reg_tcfg[0], 1) + 1) *
 160                 (GET_DIVIDER(s->reg_tcfg[1], id)));
 161     } else {
 162         s->timer[id].freq = 24000000 /
 163         ((GET_PRESCALER(s->reg_tcfg[0], 0) + 1) *
 164                 (GET_DIVIDER(s->reg_tcfg[1], id)));
 165     }
 166
 167     if (freq != s->timer[id].freq) {
 168         ptimer_set_freq(s->timer[id].ptimer, s->timer[id].freq);
 169         DPRINTF("freq=%dHz\n", s->timer[id].freq);
 170     }
 171 }
 172
 173 /*
 174  * Counter tick handler
 175  */
 176 static void exynos4210_pwm_tick(void *opaque)
 177 {
 178     Exynos4210PWM *s = (Exynos4210PWM *)opaque;
 179     Exynos4210PWMState *p = (Exynos4210PWMState *)s->parent;
 180     uint32_t id = s->id;
 181     bool cmp;
 182
 183     DPRINTF("timer %d tick\n", id);
 184
 185     /* set irq status */
 186     p->reg_tint_cstat |= TINT_CSTAT_STATUS(id);
 187
 188     /* raise IRQ */
 189     if (p->reg_tint_cstat & TINT_CSTAT_ENABLE(id)) {
 190         DPRINTF("timer %d IRQ\n", id);
 191         qemu_irq_raise(p->timer[id].irq);
 192     }
 193
 194     /* reload timer */
 195     if (id != 4) {
 196         cmp = p->reg_tcon & TCON_TIMER_AUTO_RELOAD(id);
 197     } else {
 198         cmp = p->reg_tcon & TCON_TIMER4_AUTO_RELOAD;
 199     }
 200
 201     if (cmp) {
 202         DPRINTF("auto reload timer %d count to %x\n", id,
 203                 p->timer[id].reg_tcntb);
 204         ptimer_set_count(p->timer[id].ptimer, p->timer[id].reg_tcntb);
 205         ptimer_run(p->timer[id].ptimer, 1);
 206     } else {
 207         /* stop timer, set status to STOP, see Basic Timer Operation */
 208         p->reg_tcon &= ~TCON_TIMER_START(id);
 209         ptimer_stop(p->timer[id].ptimer);
 210     }
 211 }
 212
 213 /*
 214  * PWM Read
 215  */
 216 static uint64_t exynos4210_pwm_read(void *opaque, hwaddr offset,
 217         unsigned size)
 218 {
 219     Exynos4210PWMState *s = (Exynos4210PWMState *)opaque;
 220     uint32_t value = 0;
 221     int index;
 222
 223     switch (offset) {
 224     case TCFG0: case TCFG1:
 225         index = (offset - TCFG0) >> 2;
 226         value = s->reg_tcfg[index];
 227         break;
 228
 229     case TCON:
 230         value = s->reg_tcon;
 231         break;
 232
 233     case TCNTB0: case TCNTB1:
 234     case TCNTB2: case TCNTB3: case TCNTB4:
 235         index = (offset - TCNTB0) / 0xC;
 236         value = s->timer[index].reg_tcntb;
 237         break;
 238
 239     case TCMPB0: case TCMPB1:
 240     case TCMPB2: case TCMPB3:
 241         index = (offset - TCMPB0) / 0xC;
 242         value = s->timer[index].reg_tcmpb;
 243         break;
 244
 245     case TCNTO0: case TCNTO1:
 246     case TCNTO2: case TCNTO3: case TCNTO4:
 247         index = (offset == TCNTO4) ? 4 : (offset - TCNTO0) / 0xC;
 248         value = ptimer_get_count(s->timer[index].ptimer);
 249         break;
 250
 251     case TINT_CSTAT:
 252         value = s->reg_tint_cstat;
 253         break;
 254
 255     default:
 256         fprintf(stderr,
 257                 "[exynos4210.pwm: bad read offset " TARGET_FMT_plx "]\n",
 258                 offset);
 259         break;
 260     }
 261     return value;
 262 }
 263
 264 /*
 265  * PWM Write
 266  */
 267 static void exynos4210_pwm_write(void *opaque, hwaddr offset,
 268         uint64_t value, unsigned size)
 269 {
 270     Exynos4210PWMState *s = (Exynos4210PWMState *)opaque;
 271     int index;
 272     uint32_t new_val;
 273     int i;
 274
 275     switch (offset) {
 276     case TCFG0: case TCFG1:
 277         index = (offset - TCFG0) >> 2;
 278         s->reg_tcfg[index] = value;
 279
 280         /* update timers frequencies */
 281         for (i = 0; i < EXYNOS4210_PWM_TIMERS_NUM; i++) {
 282             exynos4210_pwm_update_freq(s, s->timer[i].id);
 283         }
 284         break;
 285
 286     case TCON:
 287         for (i = 0; i < EXYNOS4210_PWM_TIMERS_NUM; i++) {
 288             if ((value & TCON_TIMER_MANUAL_UPD(i)) >
 289             (s->reg_tcon & TCON_TIMER_MANUAL_UPD(i))) {
 290                 /*
 291                  * TCNTB and TCMPB are loaded into TCNT and TCMP.
 292                  * Update timers.
 293                  */
 294
 295                 /* this will start timer to run, this ok, because
 296                  * during processing start bit timer will be stopped
 297                  * if needed */
 298                 ptimer_set_count(s->timer[i].ptimer, s->timer[i].reg_tcntb);
 299                 DPRINTF("set timer %d count to %x\n", i,
 300                         s->timer[i].reg_tcntb);
 301             }
 302
 303             if ((value & TCON_TIMER_START(i)) >
 304             (s->reg_tcon & TCON_TIMER_START(i))) {
 305                 /* changed to start */
 306                 ptimer_run(s->timer[i].ptimer, 1);
 307                 DPRINTF("run timer %d\n", i);
 308             }
 309
 310             if ((value & TCON_TIMER_START(i)) <
 311                     (s->reg_tcon & TCON_TIMER_START(i))) {
 312                 /* changed to stop */
 313                 ptimer_stop(s->timer[i].ptimer);
 314                 DPRINTF("stop timer %d\n", i);
 315             }
 316         }
 317         s->reg_tcon = value;
 318         break;
 319
 320     case TCNTB0: case TCNTB1:
 321     case TCNTB2: case TCNTB3: case TCNTB4:
 322         index = (offset - TCNTB0) / 0xC;
 323         s->timer[index].reg_tcntb = value;
 324         break;
 325
 326     case TCMPB0: case TCMPB1:
 327     case TCMPB2: case TCMPB3:
 328         index = (offset - TCMPB0) / 0xC;
 329         s->timer[index].reg_tcmpb = value;
 330         break;
 331
 332     case TINT_CSTAT:
 333         new_val = (s->reg_tint_cstat & 0x3E0) + (0x1F & value);
 334         new_val &= ~(0x3E0 & value);
 335
 336         for (i = 0; i < EXYNOS4210_PWM_TIMERS_NUM; i++) {
 337             if ((new_val & TINT_CSTAT_STATUS(i)) <
 338                     (s->reg_tint_cstat & TINT_CSTAT_STATUS(i))) {
 339                 qemu_irq_lower(s->timer[i].irq);
 340             }
 341         }
 342
 343         s->reg_tint_cstat = new_val;
 344         break;
 345
 346     default:
 347         fprintf(stderr,
 348                 "[exynos4210.pwm: bad write offset " TARGET_FMT_plx "]\n",
 349                 offset);
 350         break;
 351
 352     }
 353 }
 354
 355 /*
 356  * Set default values to timer fields and registers
 357  */
 358 static void exynos4210_pwm_reset(DeviceState *d)
 359 {
 360     Exynos4210PWMState *s = EXYNOS4210_PWM(d);
 361     int i;
 362     s->reg_tcfg[0] = 0x0101;
 363     s->reg_tcfg[1] = 0x0;
 364     s->reg_tcon = 0;
 365     s->reg_tint_cstat = 0;
 366     for (i = 0; i < EXYNOS4210_PWM_TIMERS_NUM; i++) {
 367         s->timer[i].reg_tcmpb = 0;
 368         s->timer[i].reg_tcntb = 0;
 369
 370         exynos4210_pwm_update_freq(s, s->timer[i].id);
 371         ptimer_stop(s->timer[i].ptimer);
 372     }
 373 }
 374
 375 static const MemoryRegionOps exynos4210_pwm_ops = {
 376     .read = exynos4210_pwm_read,
 377     .write = exynos4210_pwm_write,
 378     .endianness = DEVICE_NATIVE_ENDIAN,
 379 };
 380
 381 /*
 382  * PWM timer initialization
 383  */
 384 static int exynos4210_pwm_init(SysBusDevice *dev)
 385 {
 386     Exynos4210PWMState *s = EXYNOS4210_PWM(dev);
 387     int i;
 388     QEMUBH *bh;
 389
 390     for (i = 0; i < EXYNOS4210_PWM_TIMERS_NUM; i++) {
 391         bh = qemu_bh_new(exynos4210_pwm_tick, &s->timer[i]);
 392         sysbus_init_irq(dev, &s->timer[i].irq);
 393         s->timer[i].ptimer = ptimer_init(bh);
 394         s->timer[i].id = i;
 395         s->timer[i].parent = s;
 396     }
 397
 398     memory_region_init_io(&s->iomem, OBJECT(s), &exynos4210_pwm_ops, s,
 399                           "exynos4210-pwm", EXYNOS4210_PWM_REG_MEM_SIZE);
 400     sysbus_init_mmio(dev, &s->iomem);
 401
 402     return 0;
 403 }
 404
 405 static void exynos4210_pwm_class_init(ObjectClass *klass, void *data)
 406 {
 407     DeviceClass *dc = DEVICE_CLASS(klass);
 408     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
 409
 410     k->init = exynos4210_pwm_init;
 411     dc->reset = exynos4210_pwm_reset;
 412     dc->vmsd = &vmstate_exynos4210_pwm_state;
 413 }
 414
 415 static const TypeInfo exynos4210_pwm_info = {
 416     .name          = TYPE_EXYNOS4210_PWM,
 417     .parent        = TYPE_SYS_BUS_DEVICE,
 418     .instance_size = sizeof(Exynos4210PWMState),
 419     .class_init    = exynos4210_pwm_class_init,
 420 };
 421
 422 static void exynos4210_pwm_register_types(void)
 423 {
 424     type_register_static(&exynos4210_pwm_info);
 425 }
 426
 427 type_init(exynos4210_pwm_register_types)