hw/sh_timer.c

   1 /*
   2  * SuperH Timer modules.
   3  *
   4  * Copyright (c) 2007 Magnus Damm
   5  * Based on arm_timer.c by Paul Brook
   6  * Copyright (c) 2005-2006 CodeSourcery.
   7  *
   8  * This code is licensed under the GPL.
   9  */
  10
  11 #include "hw/hw.h"
  12 #include "hw/sh.h"
  13 #include "qemu/timer.h"
  14 #include "exec/address-spaces.h"
  15 #include "hw/ptimer.h"
  16
  17 //#define DEBUG_TIMER
  18
  19 #define TIMER_TCR_TPSC          (7 << 0)
  20 #define TIMER_TCR_CKEG          (3 << 3)
  21 #define TIMER_TCR_UNIE          (1 << 5)
  22 #define TIMER_TCR_ICPE          (3 << 6)
  23 #define TIMER_TCR_UNF           (1 << 8)
  24 #define TIMER_TCR_ICPF          (1 << 9)
  25 #define TIMER_TCR_RESERVED      (0x3f << 10)
  26
  27 #define TIMER_FEAT_CAPT   (1 << 0)
  28 #define TIMER_FEAT_EXTCLK (1 << 1)
  29
  30 #define OFFSET_TCOR   0
  31 #define OFFSET_TCNT   1
  32 #define OFFSET_TCR    2
  33 #define OFFSET_TCPR   3
  34
  35 typedef struct {
  36     ptimer_state *timer;
  37     uint32_t tcnt;
  38     uint32_t tcor;
  39     uint32_t tcr;
  40     uint32_t tcpr;
  41     int freq;
  42     int int_level;
  43     int old_level;
  44     int feat;
  45     int enabled;
  46     qemu_irq irq;
  47 } sh_timer_state;
  48
  49 /* Check all active timers, and schedule the next timer interrupt. */
  50
  51 static void sh_timer_update(sh_timer_state *s)
  52 {
  53     int new_level = s->int_level && (s->tcr & TIMER_TCR_UNIE);
  54
  55     if (new_level != s->old_level)
  56       qemu_set_irq (s->irq, new_level);
  57
  58     s->old_level = s->int_level;
  59     s->int_level = new_level;
  60 }
  61
  62 static uint32_t sh_timer_read(void *opaque, hwaddr offset)
  63 {
  64     sh_timer_state *s = (sh_timer_state *)opaque;
  65
  66     switch (offset >> 2) {
  67     case OFFSET_TCOR:
  68         return s->tcor;
  69     case OFFSET_TCNT:
  70         return ptimer_get_count(s->timer);
  71     case OFFSET_TCR:
  72         return s->tcr | (s->int_level ? TIMER_TCR_UNF : 0);
  73     case OFFSET_TCPR:
  74         if (s->feat & TIMER_FEAT_CAPT)
  75             return s->tcpr;
  76     default:
  77         hw_error("sh_timer_read: Bad offset %x\n", (int)offset);
  78         return 0;
  79     }
  80 }
  81
  82 static void sh_timer_write(void *opaque, hwaddr offset,
  83                             uint32_t value)
  84 {
  85     sh_timer_state *s = (sh_timer_state *)opaque;
  86     int freq;
  87
  88     switch (offset >> 2) {
  89     case OFFSET_TCOR:
  90         s->tcor = value;
  91         ptimer_set_limit(s->timer, s->tcor, 0);
  92         break;
  93     case OFFSET_TCNT:
  94         s->tcnt = value;
  95         ptimer_set_count(s->timer, s->tcnt);
  96         break;
  97     case OFFSET_TCR:
  98         if (s->enabled) {
  99             /* Pause the timer if it is running.  This may cause some
 100                inaccuracy dure to rounding, but avoids a whole lot of other
 101                messyness.  */
 102             ptimer_stop(s->timer);
 103         }
 104         freq = s->freq;
 105         /* ??? Need to recalculate expiry time after changing divisor.  */
 106         switch (value & TIMER_TCR_TPSC) {
 107         case 0: freq >>= 2; break;
 108         case 1: freq >>= 4; break;
 109         case 2: freq >>= 6; break;
 110         case 3: freq >>= 8; break;
 111         case 4: freq >>= 10; break;
 112         case 6:
 113         case 7: if (s->feat & TIMER_FEAT_EXTCLK) break;
 114         default: hw_error("sh_timer_write: Reserved TPSC value\n"); break;
 115         }
 116         switch ((value & TIMER_TCR_CKEG) >> 3) {
 117         case 0: break;
 118         case 1:
 119         case 2:
 120         case 3: if (s->feat & TIMER_FEAT_EXTCLK) break;
 121         default: hw_error("sh_timer_write: Reserved CKEG value\n"); break;
 122         }
 123         switch ((value & TIMER_TCR_ICPE) >> 6) {
 124         case 0: break;
 125         case 2:
 126         case 3: if (s->feat & TIMER_FEAT_CAPT) break;
 127         default: hw_error("sh_timer_write: Reserved ICPE value\n"); break;
 128         }
 129         if ((value & TIMER_TCR_UNF) == 0)
 130             s->int_level = 0;
 131
 132         value &= ~TIMER_TCR_UNF;
 133
 134         if ((value & TIMER_TCR_ICPF) && (!(s->feat & TIMER_FEAT_CAPT)))
 135             hw_error("sh_timer_write: Reserved ICPF value\n");
 136
 137         value &= ~TIMER_TCR_ICPF; /* capture not supported */
 138
 139         if (value & TIMER_TCR_RESERVED)
 140             hw_error("sh_timer_write: Reserved TCR bits set\n");
 141         s->tcr = value;
 142         ptimer_set_limit(s->timer, s->tcor, 0);
 143         ptimer_set_freq(s->timer, freq);
 144         if (s->enabled) {
 145             /* Restart the timer if still enabled.  */
 146             ptimer_run(s->timer, 0);
 147         }
 148         break;
 149     case OFFSET_TCPR:
 150         if (s->feat & TIMER_FEAT_CAPT) {
 151             s->tcpr = value;
 152             break;
 153         }
 154     default:
 155         hw_error("sh_timer_write: Bad offset %x\n", (int)offset);
 156     }
 157     sh_timer_update(s);
 158 }
 159
 160 static void sh_timer_start_stop(void *opaque, int enable)
 161 {
 162     sh_timer_state *s = (sh_timer_state *)opaque;
 163
 164 #ifdef DEBUG_TIMER
 165     printf("sh_timer_start_stop %d (%d)\n", enable, s->enabled);
 166 #endif
 167
 168     if (s->enabled && !enable) {
 169         ptimer_stop(s->timer);
 170     }
 171     if (!s->enabled && enable) {
 172         ptimer_run(s->timer, 0);
 173     }
 174     s->enabled = !!enable;
 175
 176 #ifdef DEBUG_TIMER
 177     printf("sh_timer_start_stop done %d\n", s->enabled);
 178 #endif
 179 }
 180
 181 static void sh_timer_tick(void *opaque)
 182 {
 183     sh_timer_state *s = (sh_timer_state *)opaque;
 184     s->int_level = s->enabled;
 185     sh_timer_update(s);
 186 }
 187
 188 static void *sh_timer_init(uint32_t freq, int feat, qemu_irq irq)
 189 {
 190     sh_timer_state *s;
 191     QEMUBH *bh;
 192
 193     s = (sh_timer_state *)g_malloc0(sizeof(sh_timer_state));
 194     s->freq = freq;
 195     s->feat = feat;
 196     s->tcor = 0xffffffff;
 197     s->tcnt = 0xffffffff;
 198     s->tcpr = 0xdeadbeef;
 199     s->tcr = 0;
 200     s->enabled = 0;
 201     s->irq = irq;
 202
 203     bh = qemu_bh_new(sh_timer_tick, s);
 204     s->timer = ptimer_init(bh);
 205
 206     sh_timer_write(s, OFFSET_TCOR >> 2, s->tcor);
 207     sh_timer_write(s, OFFSET_TCNT >> 2, s->tcnt);
 208     sh_timer_write(s, OFFSET_TCPR >> 2, s->tcpr);
 209     sh_timer_write(s, OFFSET_TCR  >> 2, s->tcpr);
 210     /* ??? Save/restore.  */
 211     return s;
 212 }
 213
 214 typedef struct {
 215     MemoryRegion iomem;
 216     MemoryRegion iomem_p4;
 217     MemoryRegion iomem_a7;
 218     void *timer[3];
 219     int level[3];
 220     uint32_t tocr;
 221     uint32_t tstr;
 222     int feat;
 223 } tmu012_state;
 224
 225 static uint64_t tmu012_read(void *opaque, hwaddr offset,
 226                             unsigned size)
 227 {
 228     tmu012_state *s = (tmu012_state *)opaque;
 229
 230 #ifdef DEBUG_TIMER
 231     printf("tmu012_read 0x%lx\n", (unsigned long) offset);
 232 #endif
 233
 234     if (offset >= 0x20) {
 235         if (!(s->feat & TMU012_FEAT_3CHAN))
 236             hw_error("tmu012_write: Bad channel offset %x\n", (int)offset);
 237         return sh_timer_read(s->timer[2], offset - 0x20);
 238     }
 239
 240     if (offset >= 0x14)
 241         return sh_timer_read(s->timer[1], offset - 0x14);
 242
 243     if (offset >= 0x08)
 244         return sh_timer_read(s->timer[0], offset - 0x08);
 245
 246     if (offset == 4)
 247         return s->tstr;
 248
 249     if ((s->feat & TMU012_FEAT_TOCR) && offset == 0)
 250         return s->tocr;
 251
 252     hw_error("tmu012_write: Bad offset %x\n", (int)offset);
 253     return 0;
 254 }
 255
 256 static void tmu012_write(void *opaque, hwaddr offset,
 257                         uint64_t value, unsigned size)
 258 {
 259     tmu012_state *s = (tmu012_state *)opaque;
 260
 261 #ifdef DEBUG_TIMER
 262     printf("tmu012_write 0x%lx 0x%08x\n", (unsigned long) offset, value);
 263 #endif
 264
 265     if (offset >= 0x20) {
 266         if (!(s->feat & TMU012_FEAT_3CHAN))
 267             hw_error("tmu012_write: Bad channel offset %x\n", (int)offset);
 268         sh_timer_write(s->timer[2], offset - 0x20, value);
 269         return;
 270     }
 271
 272     if (offset >= 0x14) {
 273         sh_timer_write(s->timer[1], offset - 0x14, value);
 274         return;
 275     }
 276
 277     if (offset >= 0x08) {
 278         sh_timer_write(s->timer[0], offset - 0x08, value);
 279         return;
 280     }
 281
 282     if (offset == 4) {
 283         sh_timer_start_stop(s->timer[0], value & (1 << 0));
 284         sh_timer_start_stop(s->timer[1], value & (1 << 1));
 285         if (s->feat & TMU012_FEAT_3CHAN)
 286             sh_timer_start_stop(s->timer[2], value & (1 << 2));
 287         else
 288             if (value & (1 << 2))
 289                 hw_error("tmu012_write: Bad channel\n");
 290
 291         s->tstr = value;
 292         return;
 293     }
 294
 295     if ((s->feat & TMU012_FEAT_TOCR) && offset == 0) {
 296         s->tocr = value & (1 << 0);
 297     }
 298 }
 299
 300 static const MemoryRegionOps tmu012_ops = {
 301     .read = tmu012_read,
 302     .write = tmu012_write,
 303     .endianness = DEVICE_NATIVE_ENDIAN,
 304 };
 305
 306 void tmu012_init(MemoryRegion *sysmem, hwaddr base,
 307                  int feat, uint32_t freq,
 308                  qemu_irq ch0_irq, qemu_irq ch1_irq,
 309                  qemu_irq ch2_irq0, qemu_irq ch2_irq1)
 310 {
 311     tmu012_state *s;
 312     int timer_feat = (feat & TMU012_FEAT_EXTCLK) ? TIMER_FEAT_EXTCLK : 0;
 313
 314     s = (tmu012_state *)g_malloc0(sizeof(tmu012_state));
 315     s->feat = feat;
 316     s->timer[0] = sh_timer_init(freq, timer_feat, ch0_irq);
 317     s->timer[1] = sh_timer_init(freq, timer_feat, ch1_irq);
 318     if (feat & TMU012_FEAT_3CHAN)
 319         s->timer[2] = sh_timer_init(freq, timer_feat | TIMER_FEAT_CAPT,
 320                                     ch2_irq0); /* ch2_irq1 not supported */
 321
 322     memory_region_init_io(&s->iomem, &tmu012_ops, s,
 323                           "timer", 0x100000000ULL);
 324
 325     memory_region_init_alias(&s->iomem_p4, "timer-p4",
 326                              &s->iomem, 0, 0x1000);
 327     memory_region_add_subregion(sysmem, P4ADDR(base), &s->iomem_p4);
 328
 329     memory_region_init_alias(&s->iomem_a7, "timer-a7",
 330                              &s->iomem, 0, 0x1000);
 331     memory_region_add_subregion(sysmem, A7ADDR(base), &s->iomem_a7);
 332     /* ??? Save/restore.  */
 333 }