xref: /qemu/hw/timer/sh_timer.c (revision 95f4dc444a99ea91534b4ac9237bdec3b2581588)
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 "qemu/timer.h"
17 #include "hw/timer/tmu012.h"
18 #include "hw/ptimer.h"
19 
20 //#define DEBUG_TIMER
21 
22 #define TIMER_TCR_TPSC          (7 << 0)
23 #define TIMER_TCR_CKEG          (3 << 3)
24 #define TIMER_TCR_UNIE          (1 << 5)
25 #define TIMER_TCR_ICPE          (3 << 6)
26 #define TIMER_TCR_UNF           (1 << 8)
27 #define TIMER_TCR_ICPF          (1 << 9)
28 #define TIMER_TCR_RESERVED      (0x3f << 10)
29 
30 #define TIMER_FEAT_CAPT   (1 << 0)
31 #define TIMER_FEAT_EXTCLK (1 << 1)
32 
33 #define OFFSET_TCOR   0
34 #define OFFSET_TCNT   1
35 #define OFFSET_TCR    2
36 #define OFFSET_TCPR   3
37 
38 typedef struct {
39     ptimer_state *timer;
40     uint32_t tcnt;
41     uint32_t tcor;
42     uint32_t tcr;
43     uint32_t tcpr;
44     int freq;
45     int int_level;
46     int old_level;
47     int feat;
48     int enabled;
49     qemu_irq irq;
50 } sh_timer_state;
51 
52 /* Check all active timers, and schedule the next timer interrupt. */
53 
54 static void sh_timer_update(sh_timer_state *s)
55 {
56     int new_level = s->int_level && (s->tcr & TIMER_TCR_UNIE);
57 
58     if (new_level != s->old_level)
59       qemu_set_irq (s->irq, new_level);
60 
61     s->old_level = s->int_level;
62     s->int_level = new_level;
63 }
64 
65 static uint32_t sh_timer_read(void *opaque, hwaddr offset)
66 {
67     sh_timer_state *s = (sh_timer_state *)opaque;
68 
69     switch (offset >> 2) {
70     case OFFSET_TCOR:
71         return s->tcor;
72     case OFFSET_TCNT:
73         return ptimer_get_count(s->timer);
74     case OFFSET_TCR:
75         return s->tcr | (s->int_level ? TIMER_TCR_UNF : 0);
76     case OFFSET_TCPR:
77         if (s->feat & TIMER_FEAT_CAPT)
78             return s->tcpr;
79         /* fall through */
80     default:
81         hw_error("sh_timer_read: Bad offset %x\n", (int)offset);
82         return 0;
83     }
84 }
85 
86 static void sh_timer_write(void *opaque, hwaddr offset,
87                             uint32_t value)
88 {
89     sh_timer_state *s = (sh_timer_state *)opaque;
90     int freq;
91 
92     switch (offset >> 2) {
93     case OFFSET_TCOR:
94         s->tcor = value;
95         ptimer_transaction_begin(s->timer);
96         ptimer_set_limit(s->timer, s->tcor, 0);
97         ptimer_transaction_commit(s->timer);
98         break;
99     case OFFSET_TCNT:
100         s->tcnt = value;
101         ptimer_transaction_begin(s->timer);
102         ptimer_set_count(s->timer, s->tcnt);
103         ptimer_transaction_commit(s->timer);
104         break;
105     case OFFSET_TCR:
106         ptimer_transaction_begin(s->timer);
107         if (s->enabled) {
108             /* Pause the timer if it is running.  This may cause some
109                inaccuracy dure to rounding, but avoids a whole lot of other
110                messyness.  */
111             ptimer_stop(s->timer);
112         }
113         freq = s->freq;
114         /* ??? Need to recalculate expiry time after changing divisor.  */
115         switch (value & TIMER_TCR_TPSC) {
116         case 0: freq >>= 2; break;
117         case 1: freq >>= 4; break;
118         case 2: freq >>= 6; break;
119         case 3: freq >>= 8; break;
120         case 4: freq >>= 10; break;
121 	case 6:
122 	case 7: if (s->feat & TIMER_FEAT_EXTCLK) break;
123 	default: hw_error("sh_timer_write: Reserved TPSC value\n"); break;
124         }
125         switch ((value & TIMER_TCR_CKEG) >> 3) {
126 	case 0: break;
127         case 1:
128         case 2:
129         case 3: if (s->feat & TIMER_FEAT_EXTCLK) break;
130 	default: hw_error("sh_timer_write: Reserved CKEG value\n"); break;
131         }
132         switch ((value & TIMER_TCR_ICPE) >> 6) {
133 	case 0: break;
134         case 2:
135         case 3: if (s->feat & TIMER_FEAT_CAPT) break;
136 	default: hw_error("sh_timer_write: Reserved ICPE value\n"); break;
137         }
138 	if ((value & TIMER_TCR_UNF) == 0)
139             s->int_level = 0;
140 
141 	value &= ~TIMER_TCR_UNF;
142 
143 	if ((value & TIMER_TCR_ICPF) && (!(s->feat & TIMER_FEAT_CAPT)))
144             hw_error("sh_timer_write: Reserved ICPF value\n");
145 
146 	value &= ~TIMER_TCR_ICPF; /* capture not supported */
147 
148 	if (value & TIMER_TCR_RESERVED)
149             hw_error("sh_timer_write: Reserved TCR bits set\n");
150         s->tcr = value;
151         ptimer_set_limit(s->timer, s->tcor, 0);
152         ptimer_set_freq(s->timer, freq);
153         if (s->enabled) {
154             /* Restart the timer if still enabled.  */
155             ptimer_run(s->timer, 0);
156         }
157         ptimer_transaction_commit(s->timer);
158         break;
159     case OFFSET_TCPR:
160         if (s->feat & TIMER_FEAT_CAPT) {
161             s->tcpr = value;
162 	    break;
163 	}
164     default:
165         hw_error("sh_timer_write: Bad offset %x\n", (int)offset);
166     }
167     sh_timer_update(s);
168 }
169 
170 static void sh_timer_start_stop(void *opaque, int enable)
171 {
172     sh_timer_state *s = (sh_timer_state *)opaque;
173 
174 #ifdef DEBUG_TIMER
175     printf("sh_timer_start_stop %d (%d)\n", enable, s->enabled);
176 #endif
177 
178     ptimer_transaction_begin(s->timer);
179     if (s->enabled && !enable) {
180         ptimer_stop(s->timer);
181     }
182     if (!s->enabled && enable) {
183         ptimer_run(s->timer, 0);
184     }
185     ptimer_transaction_commit(s->timer);
186     s->enabled = !!enable;
187 
188 #ifdef DEBUG_TIMER
189     printf("sh_timer_start_stop done %d\n", s->enabled);
190 #endif
191 }
192 
193 static void sh_timer_tick(void *opaque)
194 {
195     sh_timer_state *s = (sh_timer_state *)opaque;
196     s->int_level = s->enabled;
197     sh_timer_update(s);
198 }
199 
200 static void *sh_timer_init(uint32_t freq, int feat, qemu_irq irq)
201 {
202     sh_timer_state *s;
203 
204     s = (sh_timer_state *)g_malloc0(sizeof(sh_timer_state));
205     s->freq = freq;
206     s->feat = feat;
207     s->tcor = 0xffffffff;
208     s->tcnt = 0xffffffff;
209     s->tcpr = 0xdeadbeef;
210     s->tcr = 0;
211     s->enabled = 0;
212     s->irq = irq;
213 
214     s->timer = ptimer_init(sh_timer_tick, s, PTIMER_POLICY_DEFAULT);
215 
216     sh_timer_write(s, OFFSET_TCOR >> 2, s->tcor);
217     sh_timer_write(s, OFFSET_TCNT >> 2, s->tcnt);
218     sh_timer_write(s, OFFSET_TCPR >> 2, s->tcpr);
219     sh_timer_write(s, OFFSET_TCR  >> 2, s->tcpr);
220     /* ??? Save/restore.  */
221     return s;
222 }
223 
224 typedef struct {
225     MemoryRegion iomem;
226     MemoryRegion iomem_p4;
227     MemoryRegion iomem_a7;
228     void *timer[3];
229     int level[3];
230     uint32_t tocr;
231     uint32_t tstr;
232     int feat;
233 } tmu012_state;
234 
235 static uint64_t tmu012_read(void *opaque, hwaddr offset,
236                             unsigned size)
237 {
238     tmu012_state *s = (tmu012_state *)opaque;
239 
240 #ifdef DEBUG_TIMER
241     printf("tmu012_read 0x%lx\n", (unsigned long) offset);
242 #endif
243 
244     if (offset >= 0x20) {
245         if (!(s->feat & TMU012_FEAT_3CHAN))
246 	    hw_error("tmu012_write: Bad channel offset %x\n", (int)offset);
247         return sh_timer_read(s->timer[2], offset - 0x20);
248     }
249 
250     if (offset >= 0x14)
251         return sh_timer_read(s->timer[1], offset - 0x14);
252 
253     if (offset >= 0x08)
254         return sh_timer_read(s->timer[0], offset - 0x08);
255 
256     if (offset == 4)
257         return s->tstr;
258 
259     if ((s->feat & TMU012_FEAT_TOCR) && offset == 0)
260         return s->tocr;
261 
262     hw_error("tmu012_write: Bad offset %x\n", (int)offset);
263     return 0;
264 }
265 
266 static void tmu012_write(void *opaque, hwaddr offset,
267                         uint64_t value, unsigned size)
268 {
269     tmu012_state *s = (tmu012_state *)opaque;
270 
271 #ifdef DEBUG_TIMER
272     printf("tmu012_write 0x%lx 0x%08x\n", (unsigned long) offset, value);
273 #endif
274 
275     if (offset >= 0x20) {
276         if (!(s->feat & TMU012_FEAT_3CHAN))
277 	    hw_error("tmu012_write: Bad channel offset %x\n", (int)offset);
278         sh_timer_write(s->timer[2], offset - 0x20, value);
279 	return;
280     }
281 
282     if (offset >= 0x14) {
283         sh_timer_write(s->timer[1], offset - 0x14, value);
284 	return;
285     }
286 
287     if (offset >= 0x08) {
288         sh_timer_write(s->timer[0], offset - 0x08, value);
289 	return;
290     }
291 
292     if (offset == 4) {
293         sh_timer_start_stop(s->timer[0], value & (1 << 0));
294         sh_timer_start_stop(s->timer[1], value & (1 << 1));
295         if (s->feat & TMU012_FEAT_3CHAN)
296             sh_timer_start_stop(s->timer[2], value & (1 << 2));
297 	else
298             if (value & (1 << 2))
299                 hw_error("tmu012_write: Bad channel\n");
300 
301 	s->tstr = value;
302 	return;
303     }
304 
305     if ((s->feat & TMU012_FEAT_TOCR) && offset == 0) {
306         s->tocr = value & (1 << 0);
307     }
308 }
309 
310 static const MemoryRegionOps tmu012_ops = {
311     .read = tmu012_read,
312     .write = tmu012_write,
313     .endianness = DEVICE_NATIVE_ENDIAN,
314 };
315 
316 void tmu012_init(MemoryRegion *sysmem, hwaddr base,
317                  int feat, uint32_t freq,
318 		 qemu_irq ch0_irq, qemu_irq ch1_irq,
319 		 qemu_irq ch2_irq0, qemu_irq ch2_irq1)
320 {
321     tmu012_state *s;
322     int timer_feat = (feat & TMU012_FEAT_EXTCLK) ? TIMER_FEAT_EXTCLK : 0;
323 
324     s = (tmu012_state *)g_malloc0(sizeof(tmu012_state));
325     s->feat = feat;
326     s->timer[0] = sh_timer_init(freq, timer_feat, ch0_irq);
327     s->timer[1] = sh_timer_init(freq, timer_feat, ch1_irq);
328     if (feat & TMU012_FEAT_3CHAN)
329         s->timer[2] = sh_timer_init(freq, timer_feat | TIMER_FEAT_CAPT,
330 				    ch2_irq0); /* ch2_irq1 not supported */
331 
332     memory_region_init_io(&s->iomem, NULL, &tmu012_ops, s,
333                           "timer", 0x100000000ULL);
334 
335     memory_region_init_alias(&s->iomem_p4, NULL, "timer-p4",
336                              &s->iomem, 0, 0x1000);
337     memory_region_add_subregion(sysmem, P4ADDR(base), &s->iomem_p4);
338 
339     memory_region_init_alias(&s->iomem_a7, NULL, "timer-a7",
340                              &s->iomem, 0, 0x1000);
341     memory_region_add_subregion(sysmem, A7ADDR(base), &s->iomem_a7);
342     /* ??? Save/restore.  */
343 }
344