xref: /qemu/hw/timer/sh_timer.c (revision 7267c0947d7e8ae5dff7bafd932c3bc285f43e5c)
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.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 #define OFFSET_TCOR   0
29 #define OFFSET_TCNT   1
30 #define OFFSET_TCR    2
31 #define OFFSET_TCPR   3
32 
33 typedef struct {
34     ptimer_state *timer;
35     uint32_t tcnt;
36     uint32_t tcor;
37     uint32_t tcr;
38     uint32_t tcpr;
39     int freq;
40     int int_level;
41     int old_level;
42     int feat;
43     int enabled;
44     qemu_irq irq;
45 } sh_timer_state;
46 
47 /* Check all active timers, and schedule the next timer interrupt. */
48 
49 static void sh_timer_update(sh_timer_state *s)
50 {
51     int new_level = s->int_level && (s->tcr & TIMER_TCR_UNIE);
52 
53     if (new_level != s->old_level)
54       qemu_set_irq (s->irq, new_level);
55 
56     s->old_level = s->int_level;
57     s->int_level = new_level;
58 }
59 
60 static uint32_t sh_timer_read(void *opaque, target_phys_addr_t offset)
61 {
62     sh_timer_state *s = (sh_timer_state *)opaque;
63 
64     switch (offset >> 2) {
65     case OFFSET_TCOR:
66         return s->tcor;
67     case OFFSET_TCNT:
68         return ptimer_get_count(s->timer);
69     case OFFSET_TCR:
70         return s->tcr | (s->int_level ? TIMER_TCR_UNF : 0);
71     case OFFSET_TCPR:
72         if (s->feat & TIMER_FEAT_CAPT)
73             return s->tcpr;
74     default:
75         hw_error("sh_timer_read: Bad offset %x\n", (int)offset);
76         return 0;
77     }
78 }
79 
80 static void sh_timer_write(void *opaque, target_phys_addr_t offset,
81                             uint32_t value)
82 {
83     sh_timer_state *s = (sh_timer_state *)opaque;
84     int freq;
85 
86     switch (offset >> 2) {
87     case OFFSET_TCOR:
88         s->tcor = value;
89         ptimer_set_limit(s->timer, s->tcor, 0);
90         break;
91     case OFFSET_TCNT:
92         s->tcnt = value;
93         ptimer_set_count(s->timer, s->tcnt);
94         break;
95     case OFFSET_TCR:
96         if (s->enabled) {
97             /* Pause the timer if it is running.  This may cause some
98                inaccuracy dure to rounding, but avoids a whole lot of other
99                messyness.  */
100             ptimer_stop(s->timer);
101         }
102         freq = s->freq;
103         /* ??? Need to recalculate expiry time after changing divisor.  */
104         switch (value & TIMER_TCR_TPSC) {
105         case 0: freq >>= 2; break;
106         case 1: freq >>= 4; break;
107         case 2: freq >>= 6; break;
108         case 3: freq >>= 8; break;
109         case 4: freq >>= 10; break;
110 	case 6:
111 	case 7: if (s->feat & TIMER_FEAT_EXTCLK) break;
112 	default: hw_error("sh_timer_write: Reserved TPSC value\n"); break;
113         }
114         switch ((value & TIMER_TCR_CKEG) >> 3) {
115 	case 0: break;
116         case 1:
117         case 2:
118         case 3: if (s->feat & TIMER_FEAT_EXTCLK) break;
119 	default: hw_error("sh_timer_write: Reserved CKEG value\n"); break;
120         }
121         switch ((value & TIMER_TCR_ICPE) >> 6) {
122 	case 0: break;
123         case 2:
124         case 3: if (s->feat & TIMER_FEAT_CAPT) break;
125 	default: hw_error("sh_timer_write: Reserved ICPE value\n"); break;
126         }
127 	if ((value & TIMER_TCR_UNF) == 0)
128             s->int_level = 0;
129 
130 	value &= ~TIMER_TCR_UNF;
131 
132 	if ((value & TIMER_TCR_ICPF) && (!(s->feat & TIMER_FEAT_CAPT)))
133             hw_error("sh_timer_write: Reserved ICPF value\n");
134 
135 	value &= ~TIMER_TCR_ICPF; /* capture not supported */
136 
137 	if (value & TIMER_TCR_RESERVED)
138             hw_error("sh_timer_write: Reserved TCR bits set\n");
139         s->tcr = value;
140         ptimer_set_limit(s->timer, s->tcor, 0);
141         ptimer_set_freq(s->timer, freq);
142         if (s->enabled) {
143             /* Restart the timer if still enabled.  */
144             ptimer_run(s->timer, 0);
145         }
146         break;
147     case OFFSET_TCPR:
148         if (s->feat & TIMER_FEAT_CAPT) {
149             s->tcpr = value;
150 	    break;
151 	}
152     default:
153         hw_error("sh_timer_write: Bad offset %x\n", (int)offset);
154     }
155     sh_timer_update(s);
156 }
157 
158 static void sh_timer_start_stop(void *opaque, int enable)
159 {
160     sh_timer_state *s = (sh_timer_state *)opaque;
161 
162 #ifdef DEBUG_TIMER
163     printf("sh_timer_start_stop %d (%d)\n", enable, s->enabled);
164 #endif
165 
166     if (s->enabled && !enable) {
167         ptimer_stop(s->timer);
168     }
169     if (!s->enabled && enable) {
170         ptimer_run(s->timer, 0);
171     }
172     s->enabled = !!enable;
173 
174 #ifdef DEBUG_TIMER
175     printf("sh_timer_start_stop done %d\n", s->enabled);
176 #endif
177 }
178 
179 static void sh_timer_tick(void *opaque)
180 {
181     sh_timer_state *s = (sh_timer_state *)opaque;
182     s->int_level = s->enabled;
183     sh_timer_update(s);
184 }
185 
186 static void *sh_timer_init(uint32_t freq, int feat, qemu_irq irq)
187 {
188     sh_timer_state *s;
189     QEMUBH *bh;
190 
191     s = (sh_timer_state *)g_malloc0(sizeof(sh_timer_state));
192     s->freq = freq;
193     s->feat = feat;
194     s->tcor = 0xffffffff;
195     s->tcnt = 0xffffffff;
196     s->tcpr = 0xdeadbeef;
197     s->tcr = 0;
198     s->enabled = 0;
199     s->irq = irq;
200 
201     bh = qemu_bh_new(sh_timer_tick, s);
202     s->timer = ptimer_init(bh);
203 
204     sh_timer_write(s, OFFSET_TCOR >> 2, s->tcor);
205     sh_timer_write(s, OFFSET_TCNT >> 2, s->tcnt);
206     sh_timer_write(s, OFFSET_TCPR >> 2, s->tcpr);
207     sh_timer_write(s, OFFSET_TCR  >> 2, s->tcpr);
208     /* ??? Save/restore.  */
209     return s;
210 }
211 
212 typedef struct {
213     void *timer[3];
214     int level[3];
215     uint32_t tocr;
216     uint32_t tstr;
217     int feat;
218 } tmu012_state;
219 
220 static uint32_t tmu012_read(void *opaque, target_phys_addr_t offset)
221 {
222     tmu012_state *s = (tmu012_state *)opaque;
223 
224 #ifdef DEBUG_TIMER
225     printf("tmu012_read 0x%lx\n", (unsigned long) offset);
226 #endif
227 
228     if (offset >= 0x20) {
229         if (!(s->feat & TMU012_FEAT_3CHAN))
230 	    hw_error("tmu012_write: Bad channel offset %x\n", (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     hw_error("tmu012_write: Bad offset %x\n", (int)offset);
247     return 0;
248 }
249 
250 static void tmu012_write(void *opaque, target_phys_addr_t offset,
251                         uint32_t value)
252 {
253     tmu012_state *s = (tmu012_state *)opaque;
254 
255 #ifdef DEBUG_TIMER
256     printf("tmu012_write 0x%lx 0x%08x\n", (unsigned long) offset, value);
257 #endif
258 
259     if (offset >= 0x20) {
260         if (!(s->feat & TMU012_FEAT_3CHAN))
261 	    hw_error("tmu012_write: Bad channel offset %x\n", (int)offset);
262         sh_timer_write(s->timer[2], offset - 0x20, value);
263 	return;
264     }
265 
266     if (offset >= 0x14) {
267         sh_timer_write(s->timer[1], offset - 0x14, value);
268 	return;
269     }
270 
271     if (offset >= 0x08) {
272         sh_timer_write(s->timer[0], offset - 0x08, value);
273 	return;
274     }
275 
276     if (offset == 4) {
277         sh_timer_start_stop(s->timer[0], value & (1 << 0));
278         sh_timer_start_stop(s->timer[1], value & (1 << 1));
279         if (s->feat & TMU012_FEAT_3CHAN)
280             sh_timer_start_stop(s->timer[2], value & (1 << 2));
281 	else
282             if (value & (1 << 2))
283                 hw_error("tmu012_write: Bad channel\n");
284 
285 	s->tstr = value;
286 	return;
287     }
288 
289     if ((s->feat & TMU012_FEAT_TOCR) && offset == 0) {
290         s->tocr = value & (1 << 0);
291     }
292 }
293 
294 static CPUReadMemoryFunc * const tmu012_readfn[] = {
295     tmu012_read,
296     tmu012_read,
297     tmu012_read
298 };
299 
300 static CPUWriteMemoryFunc * const tmu012_writefn[] = {
301     tmu012_write,
302     tmu012_write,
303     tmu012_write
304 };
305 
306 void tmu012_init(target_phys_addr_t base, int feat, uint32_t freq,
307 		 qemu_irq ch0_irq, qemu_irq ch1_irq,
308 		 qemu_irq ch2_irq0, qemu_irq ch2_irq1)
309 {
310     int iomemtype;
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     iomemtype = cpu_register_io_memory(tmu012_readfn,
322                                        tmu012_writefn, s,
323                                        DEVICE_NATIVE_ENDIAN);
324     cpu_register_physical_memory(P4ADDR(base), 0x00001000, iomemtype);
325     cpu_register_physical_memory(A7ADDR(base), 0x00001000, iomemtype);
326     /* ??? Save/restore.  */
327 }
328