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 licenced under the GPL.
   9  */
  10
  11 #include "hw.h"
  12 #include "sh.h"
  13 #include "qemu-timer.h"
  14
  15 //#define DEBUG_TIMER
  16
  17 #define TIMER_TCR_TPSC          (7 << 0)
  18 #define TIMER_TCR_CKEG          (3 << 3)
  19 #define TIMER_TCR_UNIE          (1 << 5)
  20 #define TIMER_TCR_ICPE          (3 << 6)
  21 #define TIMER_TCR_UNF           (1 << 8)
  22 #define TIMER_TCR_ICPF          (1 << 9)
  23 #define TIMER_TCR_RESERVED      (0x3f << 10)
  24
  25 #define TIMER_FEAT_CAPT   (1 << 0)
  26 #define TIMER_FEAT_EXTCLK (1 << 1)
  27
  28 typedef struct {
  29     ptimer_state *timer;
  30     uint32_t tcnt;
  31     uint32_t tcor;
  32     uint32_t tcr;
  33     uint32_t tcpr;
  34     int freq;
  35     int int_level;
  36     int old_level;
  37     int feat;
  38     int enabled;
  39     qemu_irq irq;
  40 } sh_timer_state;
  41
  42 /* Check all active timers, and schedule the next timer interrupt. */
  43
  44 static void sh_timer_update(sh_timer_state *s)
  45 {
  46     int new_level = s->int_level && (s->tcr & TIMER_TCR_UNIE);
  47
  48     if (new_level != s->old_level)
  49       qemu_set_irq (s->irq, new_level);
  50
  51     s->old_level = s->int_level;
  52     s->int_level = new_level;
  53 }
  54
  55 static uint32_t sh_timer_read(void *opaque, target_phys_addr_t offset)
  56 {
  57     sh_timer_state *s = (sh_timer_state *)opaque;
  58
  59     switch (offset >> 2) {
  60     case 0:
  61         return s->tcor;
  62     case 1:
  63         return ptimer_get_count(s->timer);
  64     case 2:
  65         return s->tcr | (s->int_level ? TIMER_TCR_UNF : 0);
  66     case 3:
  67         if (s->feat & TIMER_FEAT_CAPT)
  68             return s->tcpr;
  69     default:
  70         cpu_abort (cpu_single_env, "sh_timer_read: Bad offset %x\n",
  71                    (int)offset);
  72         return 0;
  73     }
  74 }
  75
  76 static void sh_timer_write(void *opaque, target_phys_addr_t offset,
  77                             uint32_t value)
  78 {
  79     sh_timer_state *s = (sh_timer_state *)opaque;
  80     int freq;
  81
  82     switch (offset >> 2) {
  83     case 0:
  84         s->tcor = value;
  85         ptimer_set_limit(s->timer, s->tcor, 0);
  86         break;
  87     case 1:
  88         s->tcnt = value;
  89         ptimer_set_count(s->timer, s->tcnt);
  90         break;
  91     case 2:
  92         if (s->enabled) {
  93             /* Pause the timer if it is running.  This may cause some
  94                inaccuracy dure to rounding, but avoids a whole lot of other
  95                messyness.  */
  96             ptimer_stop(s->timer);
  97         }
  98         freq = s->freq;
  99         /* ??? Need to recalculate expiry time after changing divisor.  */
 100         switch (value & TIMER_TCR_TPSC) {
 101         case 0: freq >>= 2; break;
 102         case 1: freq >>= 4; break;
 103         case 2: freq >>= 6; break;
 104         case 3: freq >>= 8; break;
 105         case 4: freq >>= 10; break;
 106         case 6:
 107         case 7: if (s->feat & TIMER_FEAT_EXTCLK) break;
 108         default: cpu_abort (cpu_single_env,
 109                            "sh_timer_write: Reserved TPSC value\n"); break;
 110         }
 111         switch ((value & TIMER_TCR_CKEG) >> 3) {
 112         case 0: break;
 113         case 1:
 114         case 2:
 115         case 3: if (s->feat & TIMER_FEAT_EXTCLK) break;
 116         default: cpu_abort (cpu_single_env,
 117                            "sh_timer_write: Reserved CKEG value\n"); break;
 118         }
 119         switch ((value & TIMER_TCR_ICPE) >> 6) {
 120         case 0: break;
 121         case 2:
 122         case 3: if (s->feat & TIMER_FEAT_CAPT) break;
 123         default: cpu_abort (cpu_single_env,
 124                            "sh_timer_write: Reserved ICPE value\n"); break;
 125         }
 126         if ((value & TIMER_TCR_UNF) == 0)
 127             s->int_level = 0;
 128
 129         value &= ~TIMER_TCR_UNF;
 130
 131         if ((value & TIMER_TCR_ICPF) && (!(s->feat & TIMER_FEAT_CAPT)))
 132             cpu_abort (cpu_single_env,
 133                        "sh_timer_write: Reserved ICPF value\n");
 134
 135         value &= ~TIMER_TCR_ICPF; /* capture not supported */
 136
 137         if (value & TIMER_TCR_RESERVED)
 138             cpu_abort (cpu_single_env,
 139                        "sh_timer_write: Reserved TCR bits set\n");
 140         s->tcr = value;
 141         ptimer_set_limit(s->timer, s->tcor, 0);
 142         ptimer_set_freq(s->timer, freq);
 143         if (s->enabled) {
 144             /* Restart the timer if still enabled.  */
 145             ptimer_run(s->timer, 0);
 146         }
 147         break;
 148     case 3:
 149         if (s->feat & TIMER_FEAT_CAPT) {
 150             s->tcpr = value;
 151             break;
 152         }
 153     default:
 154         cpu_abort (cpu_single_env, "sh_timer_write: Bad offset %x\n",
 155                    (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 *)qemu_mallocz(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->tcor = 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     /* ??? Save/restore.  */
 206     return s;
 207 }
 208
 209 typedef struct {
 210     void *timer[3];
 211     int level[3];
 212     uint32_t tocr;
 213     uint32_t tstr;
 214     target_phys_addr_t base;
 215     int feat;
 216 } tmu012_state;
 217
 218 static uint32_t tmu012_read(void *opaque, target_phys_addr_t offset)
 219 {
 220     tmu012_state *s = (tmu012_state *)opaque;
 221
 222 #ifdef DEBUG_TIMER
 223     printf("tmu012_read 0x%lx\n", (unsigned long) offset);
 224 #endif
 225     offset -= s->base;
 226
 227     if (offset >= 0x20) {
 228         if (!(s->feat & TMU012_FEAT_3CHAN))
 229             cpu_abort (cpu_single_env, "tmu012_write: Bad channel offset %x\n",
 230                        (int)offset);
 231         return sh_timer_read(s->timer[2], offset - 0x20);
 232     }
 233
 234     if (offset >= 0x14)
 235         return sh_timer_read(s->timer[1], offset - 0x14);
 236
 237     if (offset >= 0x08)
 238         return sh_timer_read(s->timer[0], offset - 0x08);
 239
 240     if (offset == 4)
 241         return s->tstr;
 242
 243     if ((s->feat & TMU012_FEAT_TOCR) && offset == 0)
 244         return s->tocr;
 245
 246     cpu_abort (cpu_single_env, "tmu012_write: Bad offset %x\n",
 247                (int)offset);
 248     return 0;
 249 }
 250
 251 static void tmu012_write(void *opaque, target_phys_addr_t offset,
 252                         uint32_t value)
 253 {
 254     tmu012_state *s = (tmu012_state *)opaque;
 255
 256 #ifdef DEBUG_TIMER
 257     printf("tmu012_write 0x%lx 0x%08x\n", (unsigned long) offset, value);
 258 #endif
 259     offset -= s->base;
 260
 261     if (offset >= 0x20) {
 262         if (!(s->feat & TMU012_FEAT_3CHAN))
 263             cpu_abort (cpu_single_env, "tmu012_write: Bad channel offset %x\n",
 264                        (int)offset);
 265         sh_timer_write(s->timer[2], offset - 0x20, value);
 266         return;
 267     }
 268
 269     if (offset >= 0x14) {
 270         sh_timer_write(s->timer[1], offset - 0x14, value);
 271         return;
 272     }
 273
 274     if (offset >= 0x08) {
 275         sh_timer_write(s->timer[0], offset - 0x08, value);
 276         return;
 277     }
 278
 279     if (offset == 4) {
 280         sh_timer_start_stop(s->timer[0], value & (1 << 0));
 281         sh_timer_start_stop(s->timer[1], value & (1 << 1));
 282         if (s->feat & TMU012_FEAT_3CHAN)
 283             sh_timer_start_stop(s->timer[2], value & (1 << 2));
 284         else
 285             if (value & (1 << 2))
 286                 cpu_abort (cpu_single_env, "tmu012_write: Bad channel\n");
 287
 288         s->tstr = value;
 289         return;
 290     }
 291
 292     if ((s->feat & TMU012_FEAT_TOCR) && offset == 0) {
 293         s->tocr = value & (1 << 0);
 294     }
 295 }
 296
 297 static CPUReadMemoryFunc *tmu012_readfn[] = {
 298     tmu012_read,
 299     tmu012_read,
 300     tmu012_read
 301 };
 302
 303 static CPUWriteMemoryFunc *tmu012_writefn[] = {
 304     tmu012_write,
 305     tmu012_write,
 306     tmu012_write
 307 };
 308
 309 void tmu012_init(target_phys_addr_t base, int feat, uint32_t freq,
 310                  qemu_irq ch0_irq, qemu_irq ch1_irq,
 311                  qemu_irq ch2_irq0, qemu_irq ch2_irq1)
 312 {
 313     int iomemtype;
 314     tmu012_state *s;
 315     int timer_feat = (feat & TMU012_FEAT_EXTCLK) ? TIMER_FEAT_EXTCLK : 0;
 316
 317     s = (tmu012_state *)qemu_mallocz(sizeof(tmu012_state));
 318     s->base = base;
 319     s->feat = feat;
 320     s->timer[0] = sh_timer_init(freq, timer_feat, ch0_irq);
 321     s->timer[1] = sh_timer_init(freq, timer_feat, ch1_irq);
 322     if (feat & TMU012_FEAT_3CHAN)
 323         s->timer[2] = sh_timer_init(freq, timer_feat | TIMER_FEAT_CAPT,
 324                                     ch2_irq0); /* ch2_irq1 not supported */
 325     iomemtype = cpu_register_io_memory(0, tmu012_readfn,
 326                                        tmu012_writefn, s);
 327     cpu_register_physical_memory(base, 0x00001000, iomemtype);
 328     /* ??? Save/restore.  */
 329 }