xref: /qemu/hw/timer/sh_timer.c (revision f64766976d39fbf2b81a25b5c5f043180383d408)
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 "qemu/osdep.h"
12  #include "exec/memory.h"
13  #include "hw/hw.h"
14  #include "hw/irq.h"
15  #include "hw/sh4/sh.h"
16  #include "hw/timer/tmu012.h"
17  #include "hw/ptimer.h"
18  
19  //#define DEBUG_TIMER
20  
21  #define TIMER_TCR_TPSC          (7 << 0)
22  #define TIMER_TCR_CKEG          (3 << 3)
23  #define TIMER_TCR_UNIE          (1 << 5)
24  #define TIMER_TCR_ICPE          (3 << 6)
25  #define TIMER_TCR_UNF           (1 << 8)
26  #define TIMER_TCR_ICPF          (1 << 9)
27  #define TIMER_TCR_RESERVED      (0x3f << 10)
28  
29  #define TIMER_FEAT_CAPT   (1 << 0)
30  #define TIMER_FEAT_EXTCLK (1 << 1)
31  
32  #define OFFSET_TCOR   0
33  #define OFFSET_TCNT   1
34  #define OFFSET_TCR    2
35  #define OFFSET_TCPR   3
36  
37  typedef struct {
38      ptimer_state *timer;
39      uint32_t tcnt;
40      uint32_t tcor;
41      uint32_t tcr;
42      uint32_t tcpr;
43      int freq;
44      int int_level;
45      int old_level;
46      int feat;
47      int enabled;
48      qemu_irq irq;
49  } sh_timer_state;
50  
51  /* Check all active timers, and schedule the next timer interrupt. */
52  
53  static void sh_timer_update(sh_timer_state *s)
54  {
55      int new_level = s->int_level && (s->tcr & TIMER_TCR_UNIE);
56  
57      if (new_level != s->old_level)
58        qemu_set_irq (s->irq, new_level);
59  
60      s->old_level = s->int_level;
61      s->int_level = new_level;
62  }
63  
64  static uint32_t sh_timer_read(void *opaque, hwaddr offset)
65  {
66      sh_timer_state *s = (sh_timer_state *)opaque;
67  
68      switch (offset >> 2) {
69      case OFFSET_TCOR:
70          return s->tcor;
71      case OFFSET_TCNT:
72          return ptimer_get_count(s->timer);
73      case OFFSET_TCR:
74          return s->tcr | (s->int_level ? TIMER_TCR_UNF : 0);
75      case OFFSET_TCPR:
76          if (s->feat & TIMER_FEAT_CAPT)
77              return s->tcpr;
78          /* fall through */
79      default:
80          hw_error("sh_timer_read: Bad offset %x\n", (int)offset);
81          return 0;
82      }
83  }
84  
85  static void sh_timer_write(void *opaque, hwaddr offset,
86                              uint32_t value)
87  {
88      sh_timer_state *s = (sh_timer_state *)opaque;
89      int freq;
90  
91      switch (offset >> 2) {
92      case OFFSET_TCOR:
93          s->tcor = value;
94          ptimer_transaction_begin(s->timer);
95          ptimer_set_limit(s->timer, s->tcor, 0);
96          ptimer_transaction_commit(s->timer);
97          break;
98      case OFFSET_TCNT:
99          s->tcnt = value;
100          ptimer_transaction_begin(s->timer);
101          ptimer_set_count(s->timer, s->tcnt);
102          ptimer_transaction_commit(s->timer);
103          break;
104      case OFFSET_TCR:
105          ptimer_transaction_begin(s->timer);
106          if (s->enabled) {
107              /* Pause the timer if it is running.  This may cause some
108                 inaccuracy dure to rounding, but avoids a whole lot of other
109                 messyness.  */
110              ptimer_stop(s->timer);
111          }
112          freq = s->freq;
113          /* ??? Need to recalculate expiry time after changing divisor.  */
114          switch (value & TIMER_TCR_TPSC) {
115          case 0: freq >>= 2; break;
116          case 1: freq >>= 4; break;
117          case 2: freq >>= 6; break;
118          case 3: freq >>= 8; break;
119          case 4: freq >>= 10; break;
120          case 6:
121          case 7:
122              if (s->feat & TIMER_FEAT_EXTCLK) {
123                  break;
124              }
125              /* fallthrough */
126          default:
127              hw_error("sh_timer_write: Reserved TPSC value\n");
128          }
129          switch ((value & TIMER_TCR_CKEG) >> 3) {
130          case 0:
131              break;
132          case 1:
133          case 2:
134          case 3:
135              if (s->feat & TIMER_FEAT_EXTCLK) {
136                  break;
137              }
138              /* fallthrough */
139          default:
140              hw_error("sh_timer_write: Reserved CKEG value\n");
141          }
142          switch ((value & TIMER_TCR_ICPE) >> 6) {
143          case 0:
144              break;
145          case 2:
146          case 3:
147              if (s->feat & TIMER_FEAT_CAPT) {
148                  break;
149              }
150              /* fallthrough */
151          default:
152              hw_error("sh_timer_write: Reserved ICPE value\n");
153          }
154          if ((value & TIMER_TCR_UNF) == 0) {
155              s->int_level = 0;
156          }
157  
158          value &= ~TIMER_TCR_UNF;
159  
160          if ((value & TIMER_TCR_ICPF) && (!(s->feat & TIMER_FEAT_CAPT))) {
161              hw_error("sh_timer_write: Reserved ICPF value\n");
162          }
163  
164          value &= ~TIMER_TCR_ICPF; /* capture not supported */
165  
166          if (value & TIMER_TCR_RESERVED) {
167              hw_error("sh_timer_write: Reserved TCR bits set\n");
168          }
169          s->tcr = value;
170          ptimer_set_limit(s->timer, s->tcor, 0);
171          ptimer_set_freq(s->timer, freq);
172          if (s->enabled) {
173              /* Restart the timer if still enabled.  */
174              ptimer_run(s->timer, 0);
175          }
176          ptimer_transaction_commit(s->timer);
177          break;
178      case OFFSET_TCPR:
179          if (s->feat & TIMER_FEAT_CAPT) {
180              s->tcpr = value;
181              break;
182          }
183          /* fallthrough */
184      default:
185          hw_error("sh_timer_write: Bad offset %x\n", (int)offset);
186      }
187      sh_timer_update(s);
188  }
189  
190  static void sh_timer_start_stop(void *opaque, int enable)
191  {
192      sh_timer_state *s = (sh_timer_state *)opaque;
193  
194  #ifdef DEBUG_TIMER
195      printf("sh_timer_start_stop %d (%d)\n", enable, s->enabled);
196  #endif
197  
198      ptimer_transaction_begin(s->timer);
199      if (s->enabled && !enable) {
200          ptimer_stop(s->timer);
201      }
202      if (!s->enabled && enable) {
203          ptimer_run(s->timer, 0);
204      }
205      ptimer_transaction_commit(s->timer);
206      s->enabled = !!enable;
207  
208  #ifdef DEBUG_TIMER
209      printf("sh_timer_start_stop done %d\n", s->enabled);
210  #endif
211  }
212  
213  static void sh_timer_tick(void *opaque)
214  {
215      sh_timer_state *s = (sh_timer_state *)opaque;
216      s->int_level = s->enabled;
217      sh_timer_update(s);
218  }
219  
220  static void *sh_timer_init(uint32_t freq, int feat, qemu_irq irq)
221  {
222      sh_timer_state *s;
223  
224      s = (sh_timer_state *)g_malloc0(sizeof(sh_timer_state));
225      s->freq = freq;
226      s->feat = feat;
227      s->tcor = 0xffffffff;
228      s->tcnt = 0xffffffff;
229      s->tcpr = 0xdeadbeef;
230      s->tcr = 0;
231      s->enabled = 0;
232      s->irq = irq;
233  
234      s->timer = ptimer_init(sh_timer_tick, s, PTIMER_POLICY_DEFAULT);
235  
236      sh_timer_write(s, OFFSET_TCOR >> 2, s->tcor);
237      sh_timer_write(s, OFFSET_TCNT >> 2, s->tcnt);
238      sh_timer_write(s, OFFSET_TCPR >> 2, s->tcpr);
239      sh_timer_write(s, OFFSET_TCR  >> 2, s->tcpr);
240      /* ??? Save/restore.  */
241      return s;
242  }
243  
244  typedef struct {
245      MemoryRegion iomem;
246      MemoryRegion iomem_p4;
247      MemoryRegion iomem_a7;
248      void *timer[3];
249      int level[3];
250      uint32_t tocr;
251      uint32_t tstr;
252      int feat;
253  } tmu012_state;
254  
255  static uint64_t tmu012_read(void *opaque, hwaddr offset,
256                              unsigned size)
257  {
258      tmu012_state *s = (tmu012_state *)opaque;
259  
260  #ifdef DEBUG_TIMER
261      printf("tmu012_read 0x%lx\n", (unsigned long) offset);
262  #endif
263  
264      if (offset >= 0x20) {
265          if (!(s->feat & TMU012_FEAT_3CHAN)) {
266              hw_error("tmu012_write: Bad channel offset %x\n", (int)offset);
267          }
268          return sh_timer_read(s->timer[2], offset - 0x20);
269      }
270  
271      if (offset >= 0x14)
272          return sh_timer_read(s->timer[1], offset - 0x14);
273  
274      if (offset >= 0x08)
275          return sh_timer_read(s->timer[0], offset - 0x08);
276  
277      if (offset == 4)
278          return s->tstr;
279  
280      if ((s->feat & TMU012_FEAT_TOCR) && offset == 0)
281          return s->tocr;
282  
283      hw_error("tmu012_write: Bad offset %x\n", (int)offset);
284      return 0;
285  }
286  
287  static void tmu012_write(void *opaque, hwaddr offset,
288                          uint64_t value, unsigned size)
289  {
290      tmu012_state *s = (tmu012_state *)opaque;
291  
292  #ifdef DEBUG_TIMER
293      printf("tmu012_write 0x%lx 0x%08x\n", (unsigned long) offset, value);
294  #endif
295  
296      if (offset >= 0x20) {
297          if (!(s->feat & TMU012_FEAT_3CHAN)) {
298              hw_error("tmu012_write: Bad channel offset %x\n", (int)offset);
299          }
300          sh_timer_write(s->timer[2], offset - 0x20, value);
301          return;
302      }
303  
304      if (offset >= 0x14) {
305          sh_timer_write(s->timer[1], offset - 0x14, value);
306          return;
307      }
308  
309      if (offset >= 0x08) {
310          sh_timer_write(s->timer[0], offset - 0x08, value);
311          return;
312      }
313  
314      if (offset == 4) {
315          sh_timer_start_stop(s->timer[0], value & (1 << 0));
316          sh_timer_start_stop(s->timer[1], value & (1 << 1));
317          if (s->feat & TMU012_FEAT_3CHAN) {
318              sh_timer_start_stop(s->timer[2], value & (1 << 2));
319          } else {
320              if (value & (1 << 2)) {
321                  hw_error("tmu012_write: Bad channel\n");
322              }
323          }
324  
325          s->tstr = value;
326          return;
327      }
328  
329      if ((s->feat & TMU012_FEAT_TOCR) && offset == 0) {
330          s->tocr = value & (1 << 0);
331      }
332  }
333  
334  static const MemoryRegionOps tmu012_ops = {
335      .read = tmu012_read,
336      .write = tmu012_write,
337      .endianness = DEVICE_NATIVE_ENDIAN,
338  };
339  
340  void tmu012_init(MemoryRegion *sysmem, hwaddr base,
341                   int feat, uint32_t freq,
342                   qemu_irq ch0_irq, qemu_irq ch1_irq,
343                   qemu_irq ch2_irq0, qemu_irq ch2_irq1)
344  {
345      tmu012_state *s;
346      int timer_feat = (feat & TMU012_FEAT_EXTCLK) ? TIMER_FEAT_EXTCLK : 0;
347  
348      s = (tmu012_state *)g_malloc0(sizeof(tmu012_state));
349      s->feat = feat;
350      s->timer[0] = sh_timer_init(freq, timer_feat, ch0_irq);
351      s->timer[1] = sh_timer_init(freq, timer_feat, ch1_irq);
352      if (feat & TMU012_FEAT_3CHAN) {
353          s->timer[2] = sh_timer_init(freq, timer_feat | TIMER_FEAT_CAPT,
354                                      ch2_irq0); /* ch2_irq1 not supported */
355      }
356  
357      memory_region_init_io(&s->iomem, NULL, &tmu012_ops, s,
358                            "timer", 0x100000000ULL);
359  
360      memory_region_init_alias(&s->iomem_p4, NULL, "timer-p4",
361                               &s->iomem, 0, 0x1000);
362      memory_region_add_subregion(sysmem, P4ADDR(base), &s->iomem_p4);
363  
364      memory_region_init_alias(&s->iomem_a7, NULL, "timer-a7",
365                               &s->iomem, 0, 0x1000);
366      memory_region_add_subregion(sysmem, A7ADDR(base), &s->iomem_a7);
367      /* ??? Save/restore.  */
368  }
369