xref: /openbmc/qemu/hw/timer/exynos4210_mct.c (revision 56c4bfb3)
1 /*
2  * Samsung exynos4210 Multi Core timer
3  *
4  * Copyright (c) 2000 - 2011 Samsung Electronics Co., Ltd.
5  * All rights reserved.
6  *
7  * Evgeny Voevodin <e.voevodin@samsung.com>
8  *
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU General Public License as published by the
11  * Free Software Foundation; either version 2 of the License, or (at your
12  * option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
17  * See the GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License along
20  * with this program; if not, see <http://www.gnu.org/licenses/>.
21  */
22 
23 /*
24  * Global Timer:
25  *
26  * Consists of two timers. First represents Free Running Counter and second
27  * is used to measure interval from FRC to nearest comparator.
28  *
29  *        0                                                           UINT64_MAX
30  *        |                              timer0                             |
31  *        | <-------------------------------------------------------------- |
32  *        | --------------------------------------------frc---------------> |
33  *        |______________________________________________|__________________|
34  *                CMP0          CMP1             CMP2    |           CMP3
35  *                                                     __|            |_
36  *                                                     |     timer1     |
37  *                                                     | -------------> |
38  *                                                    frc              CMPx
39  *
40  * Problem: when implementing global timer as is, overflow arises.
41  * next_time = cur_time + period * count;
42  * period and count are 64 bits width.
43  * Lets arm timer for MCT_GT_COUNTER_STEP count and update internal G_CNT
44  * register during each event.
45  *
46  * Problem: both timers need to be implemented using MCT_XT_COUNTER_STEP because
47  * local timer contains two counters: TCNT and ICNT. TCNT == 0 -> ICNT--.
48  * IRQ is generated when ICNT riches zero. Implementation where TCNT == 0
49  * generates IRQs suffers from too frequently events. Better to have one
50  * uint64_t counter equal to TCNT*ICNT and arm ptimer.c for a minimum(TCNT*ICNT,
51  * MCT_GT_COUNTER_STEP); (yes, if target tunes ICNT * TCNT to be too low values,
52  * there is no way to avoid frequently events).
53  */
54 
55 #include "hw/sysbus.h"
56 #include "qemu/timer.h"
57 #include "qemu-common.h"
58 #include "hw/ptimer.h"
59 
60 #include "hw/arm/exynos4210.h"
61 
62 //#define DEBUG_MCT
63 
64 #ifdef DEBUG_MCT
65 #define DPRINTF(fmt, ...) \
66         do { fprintf(stdout, "MCT: [%24s:%5d] " fmt, __func__, __LINE__, \
67                      ## __VA_ARGS__); } while (0)
68 #else
69 #define DPRINTF(fmt, ...) do {} while (0)
70 #endif
71 
72 #define    MCT_CFG          0x000
73 #define    G_CNT_L          0x100
74 #define    G_CNT_U          0x104
75 #define    G_CNT_WSTAT      0x110
76 #define    G_COMP0_L        0x200
77 #define    G_COMP0_U        0x204
78 #define    G_COMP0_ADD_INCR 0x208
79 #define    G_COMP1_L        0x210
80 #define    G_COMP1_U        0x214
81 #define    G_COMP1_ADD_INCR 0x218
82 #define    G_COMP2_L        0x220
83 #define    G_COMP2_U        0x224
84 #define    G_COMP2_ADD_INCR 0x228
85 #define    G_COMP3_L        0x230
86 #define    G_COMP3_U        0x234
87 #define    G_COMP3_ADD_INCR 0x238
88 #define    G_TCON           0x240
89 #define    G_INT_CSTAT      0x244
90 #define    G_INT_ENB        0x248
91 #define    G_WSTAT          0x24C
92 #define    L0_TCNTB         0x300
93 #define    L0_TCNTO         0x304
94 #define    L0_ICNTB         0x308
95 #define    L0_ICNTO         0x30C
96 #define    L0_FRCNTB        0x310
97 #define    L0_FRCNTO        0x314
98 #define    L0_TCON          0x320
99 #define    L0_INT_CSTAT     0x330
100 #define    L0_INT_ENB       0x334
101 #define    L0_WSTAT         0x340
102 #define    L1_TCNTB         0x400
103 #define    L1_TCNTO         0x404
104 #define    L1_ICNTB         0x408
105 #define    L1_ICNTO         0x40C
106 #define    L1_FRCNTB        0x410
107 #define    L1_FRCNTO        0x414
108 #define    L1_TCON          0x420
109 #define    L1_INT_CSTAT     0x430
110 #define    L1_INT_ENB       0x434
111 #define    L1_WSTAT         0x440
112 
113 #define MCT_CFG_GET_PRESCALER(x)    ((x) & 0xFF)
114 #define MCT_CFG_GET_DIVIDER(x)      (1 << ((x) >> 8 & 7))
115 
116 #define GET_G_COMP_IDX(offset)          (((offset) - G_COMP0_L) / 0x10)
117 #define GET_G_COMP_ADD_INCR_IDX(offset) (((offset) - G_COMP0_ADD_INCR) / 0x10)
118 
119 #define G_COMP_L(x) (G_COMP0_L + (x) * 0x10)
120 #define G_COMP_U(x) (G_COMP0_U + (x) * 0x10)
121 
122 #define G_COMP_ADD_INCR(x)  (G_COMP0_ADD_INCR + (x) * 0x10)
123 
124 /* MCT bits */
125 #define G_TCON_COMP_ENABLE(x)   (1 << 2 * (x))
126 #define G_TCON_AUTO_ICREMENT(x) (1 << (2 * (x) + 1))
127 #define G_TCON_TIMER_ENABLE     (1 << 8)
128 
129 #define G_INT_ENABLE(x)         (1 << (x))
130 #define G_INT_CSTAT_COMP(x)     (1 << (x))
131 
132 #define G_CNT_WSTAT_L           1
133 #define G_CNT_WSTAT_U           2
134 
135 #define G_WSTAT_COMP_L(x)       (1 << 4 * (x))
136 #define G_WSTAT_COMP_U(x)       (1 << ((4 * (x)) + 1))
137 #define G_WSTAT_COMP_ADDINCR(x) (1 << ((4 * (x)) + 2))
138 #define G_WSTAT_TCON_WRITE      (1 << 16)
139 
140 #define GET_L_TIMER_IDX(offset) ((((offset) & 0xF00) - L0_TCNTB) / 0x100)
141 #define GET_L_TIMER_CNT_REG_IDX(offset, lt_i) \
142         (((offset) - (L0_TCNTB + 0x100 * (lt_i))) >> 2)
143 
144 #define L_ICNTB_MANUAL_UPDATE   (1 << 31)
145 
146 #define L_TCON_TICK_START       (1)
147 #define L_TCON_INT_START        (1 << 1)
148 #define L_TCON_INTERVAL_MODE    (1 << 2)
149 #define L_TCON_FRC_START        (1 << 3)
150 
151 #define L_INT_CSTAT_INTCNT      (1 << 0)
152 #define L_INT_CSTAT_FRCCNT      (1 << 1)
153 
154 #define L_INT_INTENB_ICNTEIE    (1 << 0)
155 #define L_INT_INTENB_FRCEIE     (1 << 1)
156 
157 #define L_WSTAT_TCNTB_WRITE     (1 << 0)
158 #define L_WSTAT_ICNTB_WRITE     (1 << 1)
159 #define L_WSTAT_FRCCNTB_WRITE   (1 << 2)
160 #define L_WSTAT_TCON_WRITE      (1 << 3)
161 
162 enum LocalTimerRegCntIndexes {
163     L_REG_CNT_TCNTB,
164     L_REG_CNT_TCNTO,
165     L_REG_CNT_ICNTB,
166     L_REG_CNT_ICNTO,
167     L_REG_CNT_FRCCNTB,
168     L_REG_CNT_FRCCNTO,
169 
170     L_REG_CNT_AMOUNT
171 };
172 
173 #define MCT_NIRQ                6
174 #define MCT_SFR_SIZE            0x444
175 
176 #define MCT_GT_CMP_NUM          4
177 
178 #define MCT_GT_MAX_VAL          UINT64_MAX
179 
180 #define MCT_GT_COUNTER_STEP     0x100000000ULL
181 #define MCT_LT_COUNTER_STEP     0x100000000ULL
182 #define MCT_LT_CNT_LOW_LIMIT    0x100
183 
184 /* global timer */
185 typedef struct {
186     qemu_irq  irq[MCT_GT_CMP_NUM];
187 
188     struct gregs {
189         uint64_t cnt;
190         uint32_t cnt_wstat;
191         uint32_t tcon;
192         uint32_t int_cstat;
193         uint32_t int_enb;
194         uint32_t wstat;
195         uint64_t comp[MCT_GT_CMP_NUM];
196         uint32_t comp_add_incr[MCT_GT_CMP_NUM];
197     } reg;
198 
199     uint64_t count;            /* Value FRC was armed with */
200     int32_t curr_comp;             /* Current comparator FRC is running to */
201 
202     ptimer_state *ptimer_frc;                   /* FRC timer */
203 
204 } Exynos4210MCTGT;
205 
206 /* local timer */
207 typedef struct {
208     int         id;             /* timer id */
209     qemu_irq    irq;            /* local timer irq */
210 
211     struct tick_timer {
212         uint32_t cnt_run;           /* cnt timer is running */
213         uint32_t int_run;           /* int timer is running */
214 
215         uint32_t last_icnto;
216         uint32_t last_tcnto;
217         uint32_t tcntb;             /* initial value for TCNTB */
218         uint32_t icntb;             /* initial value for ICNTB */
219 
220         /* for step mode */
221         uint64_t    distance;       /* distance to count to the next event */
222         uint64_t    progress;       /* progress when counting by steps */
223         uint64_t    count;          /* count to arm timer with */
224 
225         ptimer_state *ptimer_tick;  /* timer for tick counter */
226     } tick_timer;
227 
228     /* use ptimer.c to represent count down timer */
229 
230     ptimer_state *ptimer_frc;   /* timer for free running counter */
231 
232     /* registers */
233     struct lregs {
234         uint32_t    cnt[L_REG_CNT_AMOUNT];
235         uint32_t    tcon;
236         uint32_t    int_cstat;
237         uint32_t    int_enb;
238         uint32_t    wstat;
239     } reg;
240 
241 } Exynos4210MCTLT;
242 
243 #define TYPE_EXYNOS4210_MCT "exynos4210.mct"
244 #define EXYNOS4210_MCT(obj) \
245     OBJECT_CHECK(Exynos4210MCTState, (obj), TYPE_EXYNOS4210_MCT)
246 
247 typedef struct Exynos4210MCTState {
248     SysBusDevice parent_obj;
249 
250     MemoryRegion iomem;
251 
252     /* Registers */
253     uint32_t    reg_mct_cfg;
254 
255     Exynos4210MCTLT l_timer[2];
256     Exynos4210MCTGT g_timer;
257 
258     uint32_t    freq;                   /* all timers tick frequency, TCLK */
259 } Exynos4210MCTState;
260 
261 /*** VMState ***/
262 static const VMStateDescription vmstate_tick_timer = {
263     .name = "exynos4210.mct.tick_timer",
264     .version_id = 1,
265     .minimum_version_id = 1,
266     .minimum_version_id_old = 1,
267     .fields = (VMStateField[]) {
268         VMSTATE_UINT32(cnt_run, struct tick_timer),
269         VMSTATE_UINT32(int_run, struct tick_timer),
270         VMSTATE_UINT32(last_icnto, struct tick_timer),
271         VMSTATE_UINT32(last_tcnto, struct tick_timer),
272         VMSTATE_UINT32(tcntb, struct tick_timer),
273         VMSTATE_UINT32(icntb, struct tick_timer),
274         VMSTATE_UINT64(distance, struct tick_timer),
275         VMSTATE_UINT64(progress, struct tick_timer),
276         VMSTATE_UINT64(count, struct tick_timer),
277         VMSTATE_PTIMER(ptimer_tick, struct tick_timer),
278         VMSTATE_END_OF_LIST()
279     }
280 };
281 
282 static const VMStateDescription vmstate_lregs = {
283     .name = "exynos4210.mct.lregs",
284     .version_id = 1,
285     .minimum_version_id = 1,
286     .minimum_version_id_old = 1,
287     .fields = (VMStateField[]) {
288         VMSTATE_UINT32_ARRAY(cnt, struct lregs, L_REG_CNT_AMOUNT),
289         VMSTATE_UINT32(tcon, struct lregs),
290         VMSTATE_UINT32(int_cstat, struct lregs),
291         VMSTATE_UINT32(int_enb, struct lregs),
292         VMSTATE_UINT32(wstat, struct lregs),
293         VMSTATE_END_OF_LIST()
294     }
295 };
296 
297 static const VMStateDescription vmstate_exynos4210_mct_lt = {
298     .name = "exynos4210.mct.lt",
299     .version_id = 1,
300     .minimum_version_id = 1,
301     .minimum_version_id_old = 1,
302     .fields = (VMStateField[]) {
303         VMSTATE_INT32(id, Exynos4210MCTLT),
304         VMSTATE_STRUCT(tick_timer, Exynos4210MCTLT, 0,
305                 vmstate_tick_timer,
306                 struct tick_timer),
307         VMSTATE_PTIMER(ptimer_frc, Exynos4210MCTLT),
308         VMSTATE_STRUCT(reg, Exynos4210MCTLT, 0,
309                 vmstate_lregs,
310                 struct lregs),
311         VMSTATE_END_OF_LIST()
312     }
313 };
314 
315 static const VMStateDescription vmstate_gregs = {
316     .name = "exynos4210.mct.lregs",
317     .version_id = 1,
318     .minimum_version_id = 1,
319     .minimum_version_id_old = 1,
320     .fields = (VMStateField[]) {
321         VMSTATE_UINT64(cnt, struct gregs),
322         VMSTATE_UINT32(cnt_wstat, struct gregs),
323         VMSTATE_UINT32(tcon, struct gregs),
324         VMSTATE_UINT32(int_cstat, struct gregs),
325         VMSTATE_UINT32(int_enb, struct gregs),
326         VMSTATE_UINT32(wstat, struct gregs),
327         VMSTATE_UINT64_ARRAY(comp, struct gregs, MCT_GT_CMP_NUM),
328         VMSTATE_UINT32_ARRAY(comp_add_incr, struct gregs,
329                 MCT_GT_CMP_NUM),
330         VMSTATE_END_OF_LIST()
331     }
332 };
333 
334 static const VMStateDescription vmstate_exynos4210_mct_gt = {
335     .name = "exynos4210.mct.lt",
336     .version_id = 1,
337     .minimum_version_id = 1,
338     .minimum_version_id_old = 1,
339     .fields = (VMStateField[]) {
340         VMSTATE_STRUCT(reg, Exynos4210MCTGT, 0, vmstate_gregs,
341                 struct gregs),
342         VMSTATE_UINT64(count, Exynos4210MCTGT),
343         VMSTATE_INT32(curr_comp, Exynos4210MCTGT),
344         VMSTATE_PTIMER(ptimer_frc, Exynos4210MCTGT),
345         VMSTATE_END_OF_LIST()
346     }
347 };
348 
349 static const VMStateDescription vmstate_exynos4210_mct_state = {
350     .name = "exynos4210.mct",
351     .version_id = 1,
352     .minimum_version_id = 1,
353     .minimum_version_id_old = 1,
354     .fields = (VMStateField[]) {
355         VMSTATE_UINT32(reg_mct_cfg, Exynos4210MCTState),
356         VMSTATE_STRUCT_ARRAY(l_timer, Exynos4210MCTState, 2, 0,
357             vmstate_exynos4210_mct_lt, Exynos4210MCTLT),
358         VMSTATE_STRUCT(g_timer, Exynos4210MCTState, 0,
359             vmstate_exynos4210_mct_gt, Exynos4210MCTGT),
360         VMSTATE_UINT32(freq, Exynos4210MCTState),
361         VMSTATE_END_OF_LIST()
362     }
363 };
364 
365 static void exynos4210_mct_update_freq(Exynos4210MCTState *s);
366 
367 /*
368  * Set counter of FRC global timer.
369  */
370 static void exynos4210_gfrc_set_count(Exynos4210MCTGT *s, uint64_t count)
371 {
372     s->count = count;
373     DPRINTF("global timer frc set count 0x%llx\n", count);
374     ptimer_set_count(s->ptimer_frc, count);
375 }
376 
377 /*
378  * Get counter of FRC global timer.
379  */
380 static uint64_t exynos4210_gfrc_get_count(Exynos4210MCTGT *s)
381 {
382     uint64_t count = 0;
383     count = ptimer_get_count(s->ptimer_frc);
384     count = s->count - count;
385     return s->reg.cnt + count;
386 }
387 
388 /*
389  * Stop global FRC timer
390  */
391 static void exynos4210_gfrc_stop(Exynos4210MCTGT *s)
392 {
393     DPRINTF("global timer frc stop\n");
394 
395     ptimer_stop(s->ptimer_frc);
396 }
397 
398 /*
399  * Start global FRC timer
400  */
401 static void exynos4210_gfrc_start(Exynos4210MCTGT *s)
402 {
403     DPRINTF("global timer frc start\n");
404 
405     ptimer_run(s->ptimer_frc, 1);
406 }
407 
408 /*
409  * Find next nearest Comparator. If current Comparator value equals to other
410  * Comparator value, skip them both
411  */
412 static int32_t exynos4210_gcomp_find(Exynos4210MCTState *s)
413 {
414     int res;
415     int i;
416     int enabled;
417     uint64_t min;
418     int min_comp_i;
419     uint64_t gfrc;
420     uint64_t distance;
421     uint64_t distance_min;
422     int comp_i;
423 
424     /* get gfrc count */
425     gfrc = exynos4210_gfrc_get_count(&s->g_timer);
426 
427     min = UINT64_MAX;
428     distance_min = UINT64_MAX;
429     comp_i = MCT_GT_CMP_NUM;
430     min_comp_i = MCT_GT_CMP_NUM;
431     enabled = 0;
432 
433     /* lookup for nearest comparator */
434     for (i = 0; i < MCT_GT_CMP_NUM; i++) {
435 
436         if (s->g_timer.reg.tcon & G_TCON_COMP_ENABLE(i)) {
437 
438             enabled = 1;
439 
440             if (s->g_timer.reg.comp[i] > gfrc) {
441                 /* Comparator is upper then FRC */
442                 distance = s->g_timer.reg.comp[i] - gfrc;
443 
444                 if (distance <= distance_min) {
445                     distance_min = distance;
446                     comp_i = i;
447                 }
448             } else {
449                 /* Comparator is below FRC, find the smallest */
450 
451                 if (s->g_timer.reg.comp[i] <= min) {
452                     min = s->g_timer.reg.comp[i];
453                     min_comp_i = i;
454                 }
455             }
456         }
457     }
458 
459     if (!enabled) {
460         /* All Comparators disabled */
461         res = -1;
462     } else if (comp_i < MCT_GT_CMP_NUM) {
463         /* Found upper Comparator */
464         res = comp_i;
465     } else {
466         /* All Comparators are below or equal to FRC  */
467         res = min_comp_i;
468     }
469 
470     DPRINTF("found comparator %d: comp 0x%llx distance 0x%llx, gfrc 0x%llx\n",
471             res,
472             s->g_timer.reg.comp[res],
473             distance_min,
474             gfrc);
475 
476     return res;
477 }
478 
479 /*
480  * Get distance to nearest Comparator
481  */
482 static uint64_t exynos4210_gcomp_get_distance(Exynos4210MCTState *s, int32_t id)
483 {
484     if (id == -1) {
485         /* no enabled Comparators, choose max distance */
486         return MCT_GT_COUNTER_STEP;
487     }
488     if (s->g_timer.reg.comp[id] - s->g_timer.reg.cnt < MCT_GT_COUNTER_STEP) {
489         return s->g_timer.reg.comp[id] - s->g_timer.reg.cnt;
490     } else {
491         return MCT_GT_COUNTER_STEP;
492     }
493 }
494 
495 /*
496  * Restart global FRC timer
497  */
498 static void exynos4210_gfrc_restart(Exynos4210MCTState *s)
499 {
500     uint64_t distance;
501 
502     exynos4210_gfrc_stop(&s->g_timer);
503 
504     s->g_timer.curr_comp = exynos4210_gcomp_find(s);
505 
506     distance = exynos4210_gcomp_get_distance(s, s->g_timer.curr_comp);
507 
508     if (distance > MCT_GT_COUNTER_STEP || !distance) {
509         distance = MCT_GT_COUNTER_STEP;
510     }
511 
512     exynos4210_gfrc_set_count(&s->g_timer, distance);
513     exynos4210_gfrc_start(&s->g_timer);
514 }
515 
516 /*
517  * Raise global timer CMP IRQ
518  */
519 static void exynos4210_gcomp_raise_irq(void *opaque, uint32_t id)
520 {
521     Exynos4210MCTGT *s = opaque;
522 
523     /* If CSTAT is pending and IRQ is enabled */
524     if ((s->reg.int_cstat & G_INT_CSTAT_COMP(id)) &&
525             (s->reg.int_enb & G_INT_ENABLE(id))) {
526         DPRINTF("gcmp timer[%d] IRQ\n", id);
527         qemu_irq_raise(s->irq[id]);
528     }
529 }
530 
531 /*
532  * Lower global timer CMP IRQ
533  */
534 static void exynos4210_gcomp_lower_irq(void *opaque, uint32_t id)
535 {
536     Exynos4210MCTGT *s = opaque;
537     qemu_irq_lower(s->irq[id]);
538 }
539 
540 /*
541  * Global timer FRC event handler.
542  * Each event occurs when internal counter reaches counter + MCT_GT_COUNTER_STEP
543  * Every time we arm global FRC timer to count for MCT_GT_COUNTER_STEP value
544  */
545 static void exynos4210_gfrc_event(void *opaque)
546 {
547     Exynos4210MCTState *s = (Exynos4210MCTState *)opaque;
548     int i;
549     uint64_t distance;
550 
551     DPRINTF("\n");
552 
553     s->g_timer.reg.cnt += s->g_timer.count;
554 
555     /* Process all comparators */
556     for (i = 0; i < MCT_GT_CMP_NUM; i++) {
557 
558         if (s->g_timer.reg.cnt == s->g_timer.reg.comp[i]) {
559             /* reached nearest comparator */
560 
561             s->g_timer.reg.int_cstat |= G_INT_CSTAT_COMP(i);
562 
563             /* Auto increment */
564             if (s->g_timer.reg.tcon & G_TCON_AUTO_ICREMENT(i)) {
565                 s->g_timer.reg.comp[i] += s->g_timer.reg.comp_add_incr[i];
566             }
567 
568             /* IRQ */
569             exynos4210_gcomp_raise_irq(&s->g_timer, i);
570         }
571     }
572 
573     /* Reload FRC to reach nearest comparator */
574     s->g_timer.curr_comp = exynos4210_gcomp_find(s);
575     distance = exynos4210_gcomp_get_distance(s, s->g_timer.curr_comp);
576     if (distance > MCT_GT_COUNTER_STEP || !distance) {
577         distance = MCT_GT_COUNTER_STEP;
578     }
579     exynos4210_gfrc_set_count(&s->g_timer, distance);
580 
581     exynos4210_gfrc_start(&s->g_timer);
582 }
583 
584 /*
585  * Get counter of FRC local timer.
586  */
587 static uint64_t exynos4210_lfrc_get_count(Exynos4210MCTLT *s)
588 {
589     return ptimer_get_count(s->ptimer_frc);
590 }
591 
592 /*
593  * Set counter of FRC local timer.
594  */
595 static void exynos4210_lfrc_update_count(Exynos4210MCTLT *s)
596 {
597     if (!s->reg.cnt[L_REG_CNT_FRCCNTB]) {
598         ptimer_set_count(s->ptimer_frc, MCT_LT_COUNTER_STEP);
599     } else {
600         ptimer_set_count(s->ptimer_frc, s->reg.cnt[L_REG_CNT_FRCCNTB]);
601     }
602 }
603 
604 /*
605  * Start local FRC timer
606  */
607 static void exynos4210_lfrc_start(Exynos4210MCTLT *s)
608 {
609     ptimer_run(s->ptimer_frc, 1);
610 }
611 
612 /*
613  * Stop local FRC timer
614  */
615 static void exynos4210_lfrc_stop(Exynos4210MCTLT *s)
616 {
617     ptimer_stop(s->ptimer_frc);
618 }
619 
620 /*
621  * Local timer free running counter tick handler
622  */
623 static void exynos4210_lfrc_event(void *opaque)
624 {
625     Exynos4210MCTLT * s = (Exynos4210MCTLT *)opaque;
626 
627     /* local frc expired */
628 
629     DPRINTF("\n");
630 
631     s->reg.int_cstat |= L_INT_CSTAT_FRCCNT;
632 
633     /* update frc counter */
634     exynos4210_lfrc_update_count(s);
635 
636     /* raise irq */
637     if (s->reg.int_enb & L_INT_INTENB_FRCEIE) {
638         qemu_irq_raise(s->irq);
639     }
640 
641     /*  we reached here, this means that timer is enabled */
642     exynos4210_lfrc_start(s);
643 }
644 
645 static uint32_t exynos4210_ltick_int_get_cnto(struct tick_timer *s);
646 static uint32_t exynos4210_ltick_cnt_get_cnto(struct tick_timer *s);
647 static void exynos4210_ltick_recalc_count(struct tick_timer *s);
648 
649 /*
650  * Action on enabling local tick int timer
651  */
652 static void exynos4210_ltick_int_start(struct tick_timer *s)
653 {
654     if (!s->int_run) {
655         s->int_run = 1;
656     }
657 }
658 
659 /*
660  * Action on disabling local tick int timer
661  */
662 static void exynos4210_ltick_int_stop(struct tick_timer *s)
663 {
664     if (s->int_run) {
665         s->last_icnto = exynos4210_ltick_int_get_cnto(s);
666         s->int_run = 0;
667     }
668 }
669 
670 /*
671  * Get count for INT timer
672  */
673 static uint32_t exynos4210_ltick_int_get_cnto(struct tick_timer *s)
674 {
675     uint32_t icnto;
676     uint64_t remain;
677     uint64_t count;
678     uint64_t counted;
679     uint64_t cur_progress;
680 
681     count = ptimer_get_count(s->ptimer_tick);
682     if (count) {
683         /* timer is still counting, called not from event */
684         counted = s->count - ptimer_get_count(s->ptimer_tick);
685         cur_progress = s->progress + counted;
686     } else {
687         /* timer expired earlier */
688         cur_progress = s->progress;
689     }
690 
691     remain = s->distance - cur_progress;
692 
693     if (!s->int_run) {
694         /* INT is stopped. */
695         icnto = s->last_icnto;
696     } else {
697         /* Both are counting */
698         icnto = remain / s->tcntb;
699     }
700 
701     return icnto;
702 }
703 
704 /*
705  * Start local tick cnt timer.
706  */
707 static void exynos4210_ltick_cnt_start(struct tick_timer *s)
708 {
709     if (!s->cnt_run) {
710 
711         exynos4210_ltick_recalc_count(s);
712         ptimer_set_count(s->ptimer_tick, s->count);
713         ptimer_run(s->ptimer_tick, 1);
714 
715         s->cnt_run = 1;
716     }
717 }
718 
719 /*
720  * Stop local tick cnt timer.
721  */
722 static void exynos4210_ltick_cnt_stop(struct tick_timer *s)
723 {
724     if (s->cnt_run) {
725 
726         s->last_tcnto = exynos4210_ltick_cnt_get_cnto(s);
727 
728         if (s->int_run) {
729             exynos4210_ltick_int_stop(s);
730         }
731 
732         ptimer_stop(s->ptimer_tick);
733 
734         s->cnt_run = 0;
735     }
736 }
737 
738 /*
739  * Get counter for CNT timer
740  */
741 static uint32_t exynos4210_ltick_cnt_get_cnto(struct tick_timer *s)
742 {
743     uint32_t tcnto;
744     uint32_t icnto;
745     uint64_t remain;
746     uint64_t counted;
747     uint64_t count;
748     uint64_t cur_progress;
749 
750     count = ptimer_get_count(s->ptimer_tick);
751     if (count) {
752         /* timer is still counting, called not from event */
753         counted = s->count - ptimer_get_count(s->ptimer_tick);
754         cur_progress = s->progress + counted;
755     } else {
756         /* timer expired earlier */
757         cur_progress = s->progress;
758     }
759 
760     remain = s->distance - cur_progress;
761 
762     if (!s->cnt_run) {
763         /* Both are stopped. */
764         tcnto = s->last_tcnto;
765     } else if (!s->int_run) {
766         /* INT counter is stopped, progress is by CNT timer */
767         tcnto = remain % s->tcntb;
768     } else {
769         /* Both are counting */
770         icnto = remain / s->tcntb;
771         if (icnto) {
772             tcnto = remain % (icnto * s->tcntb);
773         } else {
774             tcnto = remain % s->tcntb;
775         }
776     }
777 
778     return tcnto;
779 }
780 
781 /*
782  * Set new values of counters for CNT and INT timers
783  */
784 static void exynos4210_ltick_set_cntb(struct tick_timer *s, uint32_t new_cnt,
785         uint32_t new_int)
786 {
787     uint32_t cnt_stopped = 0;
788     uint32_t int_stopped = 0;
789 
790     if (s->cnt_run) {
791         exynos4210_ltick_cnt_stop(s);
792         cnt_stopped = 1;
793     }
794 
795     if (s->int_run) {
796         exynos4210_ltick_int_stop(s);
797         int_stopped = 1;
798     }
799 
800     s->tcntb = new_cnt + 1;
801     s->icntb = new_int + 1;
802 
803     if (cnt_stopped) {
804         exynos4210_ltick_cnt_start(s);
805     }
806     if (int_stopped) {
807         exynos4210_ltick_int_start(s);
808     }
809 
810 }
811 
812 /*
813  * Calculate new counter value for tick timer
814  */
815 static void exynos4210_ltick_recalc_count(struct tick_timer *s)
816 {
817     uint64_t to_count;
818 
819     if ((s->cnt_run && s->last_tcnto) || (s->int_run && s->last_icnto)) {
820         /*
821          * one or both timers run and not counted to the end;
822          * distance is not passed, recalculate with last_tcnto * last_icnto
823          */
824 
825         if (s->last_tcnto) {
826             to_count = s->last_tcnto * s->last_icnto;
827         } else {
828             to_count = s->last_icnto;
829         }
830     } else {
831         /* distance is passed, recalculate with tcnto * icnto */
832         if (s->icntb) {
833             s->distance = s->tcntb * s->icntb;
834         } else {
835             s->distance = s->tcntb;
836         }
837 
838         to_count = s->distance;
839         s->progress = 0;
840     }
841 
842     if (to_count > MCT_LT_COUNTER_STEP) {
843         /* count by step */
844         s->count = MCT_LT_COUNTER_STEP;
845     } else {
846         s->count = to_count;
847     }
848 }
849 
850 /*
851  * Initialize tick_timer
852  */
853 static void exynos4210_ltick_timer_init(struct tick_timer *s)
854 {
855     exynos4210_ltick_int_stop(s);
856     exynos4210_ltick_cnt_stop(s);
857 
858     s->count = 0;
859     s->distance = 0;
860     s->progress = 0;
861     s->icntb = 0;
862     s->tcntb = 0;
863 }
864 
865 /*
866  * tick_timer event.
867  * Raises when abstract tick_timer expires.
868  */
869 static void exynos4210_ltick_timer_event(struct tick_timer *s)
870 {
871     s->progress += s->count;
872 }
873 
874 /*
875  * Local timer tick counter handler.
876  * Don't use reloaded timers. If timer counter = zero
877  * then handler called but after handler finished no
878  * timer reload occurs.
879  */
880 static void exynos4210_ltick_event(void *opaque)
881 {
882     Exynos4210MCTLT * s = (Exynos4210MCTLT *)opaque;
883     uint32_t tcnto;
884     uint32_t icnto;
885 #ifdef DEBUG_MCT
886     static uint64_t time1[2] = {0};
887     static uint64_t time2[2] = {0};
888 #endif
889 
890     /* Call tick_timer event handler, it will update its tcntb and icntb. */
891     exynos4210_ltick_timer_event(&s->tick_timer);
892 
893     /* get tick_timer cnt */
894     tcnto = exynos4210_ltick_cnt_get_cnto(&s->tick_timer);
895 
896     /* get tick_timer int */
897     icnto = exynos4210_ltick_int_get_cnto(&s->tick_timer);
898 
899     /* raise IRQ if needed */
900     if (!icnto && s->reg.tcon & L_TCON_INT_START) {
901         /* INT counter enabled and expired */
902 
903         s->reg.int_cstat |= L_INT_CSTAT_INTCNT;
904 
905         /* raise interrupt if enabled */
906         if (s->reg.int_enb & L_INT_INTENB_ICNTEIE) {
907 #ifdef DEBUG_MCT
908             time2[s->id] = qemu_get_clock_ns(vm_clock);
909             DPRINTF("local timer[%d] IRQ: %llx\n", s->id,
910                     time2[s->id] - time1[s->id]);
911             time1[s->id] = time2[s->id];
912 #endif
913             qemu_irq_raise(s->irq);
914         }
915 
916         /* reload ICNTB */
917         if (s->reg.tcon & L_TCON_INTERVAL_MODE) {
918             exynos4210_ltick_set_cntb(&s->tick_timer,
919                     s->reg.cnt[L_REG_CNT_TCNTB],
920                     s->reg.cnt[L_REG_CNT_ICNTB]);
921         }
922     } else {
923         /* reload TCNTB */
924         if (!tcnto) {
925             exynos4210_ltick_set_cntb(&s->tick_timer,
926                     s->reg.cnt[L_REG_CNT_TCNTB],
927                     icnto);
928         }
929     }
930 
931     /* start tick_timer cnt */
932     exynos4210_ltick_cnt_start(&s->tick_timer);
933 
934     /* start tick_timer int */
935     exynos4210_ltick_int_start(&s->tick_timer);
936 }
937 
938 /* update timer frequency */
939 static void exynos4210_mct_update_freq(Exynos4210MCTState *s)
940 {
941     uint32_t freq = s->freq;
942     s->freq = 24000000 /
943             ((MCT_CFG_GET_PRESCALER(s->reg_mct_cfg)+1) *
944                     MCT_CFG_GET_DIVIDER(s->reg_mct_cfg));
945 
946     if (freq != s->freq) {
947         DPRINTF("freq=%dHz\n", s->freq);
948 
949         /* global timer */
950         ptimer_set_freq(s->g_timer.ptimer_frc, s->freq);
951 
952         /* local timer */
953         ptimer_set_freq(s->l_timer[0].tick_timer.ptimer_tick, s->freq);
954         ptimer_set_freq(s->l_timer[0].ptimer_frc, s->freq);
955         ptimer_set_freq(s->l_timer[1].tick_timer.ptimer_tick, s->freq);
956         ptimer_set_freq(s->l_timer[1].ptimer_frc, s->freq);
957     }
958 }
959 
960 /* set defaul_timer values for all fields */
961 static void exynos4210_mct_reset(DeviceState *d)
962 {
963     Exynos4210MCTState *s = EXYNOS4210_MCT(d);
964     uint32_t i;
965 
966     s->reg_mct_cfg = 0;
967 
968     /* global timer */
969     memset(&s->g_timer.reg, 0, sizeof(s->g_timer.reg));
970     exynos4210_gfrc_stop(&s->g_timer);
971 
972     /* local timer */
973     memset(s->l_timer[0].reg.cnt, 0, sizeof(s->l_timer[0].reg.cnt));
974     memset(s->l_timer[1].reg.cnt, 0, sizeof(s->l_timer[1].reg.cnt));
975     for (i = 0; i < 2; i++) {
976         s->l_timer[i].reg.int_cstat = 0;
977         s->l_timer[i].reg.int_enb = 0;
978         s->l_timer[i].reg.tcon = 0;
979         s->l_timer[i].reg.wstat = 0;
980         s->l_timer[i].tick_timer.count = 0;
981         s->l_timer[i].tick_timer.distance = 0;
982         s->l_timer[i].tick_timer.progress = 0;
983         ptimer_stop(s->l_timer[i].ptimer_frc);
984 
985         exynos4210_ltick_timer_init(&s->l_timer[i].tick_timer);
986     }
987 
988     exynos4210_mct_update_freq(s);
989 
990 }
991 
992 /* Multi Core Timer read */
993 static uint64_t exynos4210_mct_read(void *opaque, hwaddr offset,
994         unsigned size)
995 {
996     Exynos4210MCTState *s = (Exynos4210MCTState *)opaque;
997     int index;
998     int shift;
999     uint64_t count;
1000     uint32_t value;
1001     int lt_i;
1002 
1003     switch (offset) {
1004 
1005     case MCT_CFG:
1006         value = s->reg_mct_cfg;
1007         break;
1008 
1009     case G_CNT_L: case G_CNT_U:
1010         shift = 8 * (offset & 0x4);
1011         count = exynos4210_gfrc_get_count(&s->g_timer);
1012         value = UINT32_MAX & (count >> shift);
1013         DPRINTF("read FRC=0x%llx\n", count);
1014         break;
1015 
1016     case G_CNT_WSTAT:
1017         value = s->g_timer.reg.cnt_wstat;
1018         break;
1019 
1020     case G_COMP_L(0): case G_COMP_L(1): case G_COMP_L(2): case G_COMP_L(3):
1021     case G_COMP_U(0): case G_COMP_U(1): case G_COMP_U(2): case G_COMP_U(3):
1022     index = GET_G_COMP_IDX(offset);
1023     shift = 8 * (offset & 0x4);
1024     value = UINT32_MAX & (s->g_timer.reg.comp[index] >> shift);
1025     break;
1026 
1027     case G_TCON:
1028         value = s->g_timer.reg.tcon;
1029         break;
1030 
1031     case G_INT_CSTAT:
1032         value = s->g_timer.reg.int_cstat;
1033         break;
1034 
1035     case G_INT_ENB:
1036         value = s->g_timer.reg.int_enb;
1037         break;
1038     case G_WSTAT:
1039         value = s->g_timer.reg.wstat;
1040         break;
1041 
1042     case G_COMP0_ADD_INCR: case G_COMP1_ADD_INCR:
1043     case G_COMP2_ADD_INCR: case G_COMP3_ADD_INCR:
1044         value = s->g_timer.reg.comp_add_incr[GET_G_COMP_ADD_INCR_IDX(offset)];
1045         break;
1046 
1047         /* Local timers */
1048     case L0_TCNTB: case L0_ICNTB: case L0_FRCNTB:
1049     case L1_TCNTB: case L1_ICNTB: case L1_FRCNTB:
1050         lt_i = GET_L_TIMER_IDX(offset);
1051         index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i);
1052         value = s->l_timer[lt_i].reg.cnt[index];
1053         break;
1054 
1055     case L0_TCNTO: case L1_TCNTO:
1056         lt_i = GET_L_TIMER_IDX(offset);
1057 
1058         value = exynos4210_ltick_cnt_get_cnto(&s->l_timer[lt_i].tick_timer);
1059         DPRINTF("local timer[%d] read TCNTO %x\n", lt_i, value);
1060         break;
1061 
1062     case L0_ICNTO: case L1_ICNTO:
1063         lt_i = GET_L_TIMER_IDX(offset);
1064 
1065         value = exynos4210_ltick_int_get_cnto(&s->l_timer[lt_i].tick_timer);
1066         DPRINTF("local timer[%d] read ICNTO %x\n", lt_i, value);
1067         break;
1068 
1069     case L0_FRCNTO: case L1_FRCNTO:
1070         lt_i = GET_L_TIMER_IDX(offset);
1071 
1072         value = exynos4210_lfrc_get_count(&s->l_timer[lt_i]);
1073 
1074         break;
1075 
1076     case L0_TCON: case L1_TCON:
1077         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1078         value = s->l_timer[lt_i].reg.tcon;
1079         break;
1080 
1081     case L0_INT_CSTAT: case L1_INT_CSTAT:
1082         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1083         value = s->l_timer[lt_i].reg.int_cstat;
1084         break;
1085 
1086     case L0_INT_ENB: case L1_INT_ENB:
1087         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1088         value = s->l_timer[lt_i].reg.int_enb;
1089         break;
1090 
1091     case L0_WSTAT: case L1_WSTAT:
1092         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1093         value = s->l_timer[lt_i].reg.wstat;
1094         break;
1095 
1096     default:
1097         hw_error("exynos4210.mct: bad read offset "
1098                 TARGET_FMT_plx "\n", offset);
1099         break;
1100     }
1101     return value;
1102 }
1103 
1104 /* MCT write */
1105 static void exynos4210_mct_write(void *opaque, hwaddr offset,
1106         uint64_t value, unsigned size)
1107 {
1108     Exynos4210MCTState *s = (Exynos4210MCTState *)opaque;
1109     int index;  /* index in buffer which represents register set */
1110     int shift;
1111     int lt_i;
1112     uint64_t new_frc;
1113     uint32_t i;
1114     uint32_t old_val;
1115 #ifdef DEBUG_MCT
1116     static uint32_t icntb_max[2] = {0};
1117     static uint32_t icntb_min[2] = {UINT32_MAX, UINT32_MAX};
1118     static uint32_t tcntb_max[2] = {0};
1119     static uint32_t tcntb_min[2] = {UINT32_MAX, UINT32_MAX};
1120 #endif
1121 
1122     new_frc = s->g_timer.reg.cnt;
1123 
1124     switch (offset) {
1125 
1126     case MCT_CFG:
1127         s->reg_mct_cfg = value;
1128         exynos4210_mct_update_freq(s);
1129         break;
1130 
1131     case G_CNT_L:
1132     case G_CNT_U:
1133         if (offset == G_CNT_L) {
1134 
1135             DPRINTF("global timer write to reg.cntl %llx\n", value);
1136 
1137             new_frc = (s->g_timer.reg.cnt & (uint64_t)UINT32_MAX << 32) + value;
1138             s->g_timer.reg.cnt_wstat |= G_CNT_WSTAT_L;
1139         }
1140         if (offset == G_CNT_U) {
1141 
1142             DPRINTF("global timer write to reg.cntu %llx\n", value);
1143 
1144             new_frc = (s->g_timer.reg.cnt & UINT32_MAX) +
1145                     ((uint64_t)value << 32);
1146             s->g_timer.reg.cnt_wstat |= G_CNT_WSTAT_U;
1147         }
1148 
1149         s->g_timer.reg.cnt = new_frc;
1150         exynos4210_gfrc_restart(s);
1151         break;
1152 
1153     case G_CNT_WSTAT:
1154         s->g_timer.reg.cnt_wstat &= ~(value);
1155         break;
1156 
1157     case G_COMP_L(0): case G_COMP_L(1): case G_COMP_L(2): case G_COMP_L(3):
1158     case G_COMP_U(0): case G_COMP_U(1): case G_COMP_U(2): case G_COMP_U(3):
1159     index = GET_G_COMP_IDX(offset);
1160     shift = 8 * (offset & 0x4);
1161     s->g_timer.reg.comp[index] =
1162             (s->g_timer.reg.comp[index] &
1163             (((uint64_t)UINT32_MAX << 32) >> shift)) +
1164             (value << shift);
1165 
1166     DPRINTF("comparator %d write 0x%llx val << %d\n", index, value, shift);
1167 
1168     if (offset&0x4) {
1169         s->g_timer.reg.wstat |= G_WSTAT_COMP_U(index);
1170     } else {
1171         s->g_timer.reg.wstat |= G_WSTAT_COMP_L(index);
1172     }
1173 
1174     exynos4210_gfrc_restart(s);
1175     break;
1176 
1177     case G_TCON:
1178         old_val = s->g_timer.reg.tcon;
1179         s->g_timer.reg.tcon = value;
1180         s->g_timer.reg.wstat |= G_WSTAT_TCON_WRITE;
1181 
1182         DPRINTF("global timer write to reg.g_tcon %llx\n", value);
1183 
1184         /* Start FRC if transition from disabled to enabled */
1185         if ((value & G_TCON_TIMER_ENABLE) > (old_val &
1186                 G_TCON_TIMER_ENABLE)) {
1187             exynos4210_gfrc_start(&s->g_timer);
1188         }
1189         if ((value & G_TCON_TIMER_ENABLE) < (old_val &
1190                 G_TCON_TIMER_ENABLE)) {
1191             exynos4210_gfrc_stop(&s->g_timer);
1192         }
1193 
1194         /* Start CMP if transition from disabled to enabled */
1195         for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1196             if ((value & G_TCON_COMP_ENABLE(i)) != (old_val &
1197                     G_TCON_COMP_ENABLE(i))) {
1198                 exynos4210_gfrc_restart(s);
1199             }
1200         }
1201         break;
1202 
1203     case G_INT_CSTAT:
1204         s->g_timer.reg.int_cstat &= ~(value);
1205         for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1206             if (value & G_INT_CSTAT_COMP(i)) {
1207                 exynos4210_gcomp_lower_irq(&s->g_timer, i);
1208             }
1209         }
1210         break;
1211 
1212     case G_INT_ENB:
1213 
1214         /* Raise IRQ if transition from disabled to enabled and CSTAT pending */
1215         for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1216             if ((value & G_INT_ENABLE(i)) > (s->g_timer.reg.tcon &
1217                     G_INT_ENABLE(i))) {
1218                 if (s->g_timer.reg.int_cstat & G_INT_CSTAT_COMP(i)) {
1219                     exynos4210_gcomp_raise_irq(&s->g_timer, i);
1220                 }
1221             }
1222 
1223             if ((value & G_INT_ENABLE(i)) < (s->g_timer.reg.tcon &
1224                     G_INT_ENABLE(i))) {
1225                 exynos4210_gcomp_lower_irq(&s->g_timer, i);
1226             }
1227         }
1228 
1229         DPRINTF("global timer INT enable %llx\n", value);
1230         s->g_timer.reg.int_enb = value;
1231         break;
1232 
1233     case G_WSTAT:
1234         s->g_timer.reg.wstat &= ~(value);
1235         break;
1236 
1237     case G_COMP0_ADD_INCR: case G_COMP1_ADD_INCR:
1238     case G_COMP2_ADD_INCR: case G_COMP3_ADD_INCR:
1239         index = GET_G_COMP_ADD_INCR_IDX(offset);
1240         s->g_timer.reg.comp_add_incr[index] = value;
1241         s->g_timer.reg.wstat |= G_WSTAT_COMP_ADDINCR(index);
1242         break;
1243 
1244         /* Local timers */
1245     case L0_TCON: case L1_TCON:
1246         lt_i = GET_L_TIMER_IDX(offset);
1247         old_val = s->l_timer[lt_i].reg.tcon;
1248 
1249         s->l_timer[lt_i].reg.wstat |= L_WSTAT_TCON_WRITE;
1250         s->l_timer[lt_i].reg.tcon = value;
1251 
1252         /* Stop local CNT */
1253         if ((value & L_TCON_TICK_START) <
1254                 (old_val & L_TCON_TICK_START)) {
1255             DPRINTF("local timer[%d] stop cnt\n", lt_i);
1256             exynos4210_ltick_cnt_stop(&s->l_timer[lt_i].tick_timer);
1257         }
1258 
1259         /* Stop local INT */
1260         if ((value & L_TCON_INT_START) <
1261                 (old_val & L_TCON_INT_START)) {
1262             DPRINTF("local timer[%d] stop int\n", lt_i);
1263             exynos4210_ltick_int_stop(&s->l_timer[lt_i].tick_timer);
1264         }
1265 
1266         /* Start local CNT */
1267         if ((value & L_TCON_TICK_START) >
1268         (old_val & L_TCON_TICK_START)) {
1269             DPRINTF("local timer[%d] start cnt\n", lt_i);
1270             exynos4210_ltick_cnt_start(&s->l_timer[lt_i].tick_timer);
1271         }
1272 
1273         /* Start local INT */
1274         if ((value & L_TCON_INT_START) >
1275         (old_val & L_TCON_INT_START)) {
1276             DPRINTF("local timer[%d] start int\n", lt_i);
1277             exynos4210_ltick_int_start(&s->l_timer[lt_i].tick_timer);
1278         }
1279 
1280         /* Start or Stop local FRC if TCON changed */
1281         if ((value & L_TCON_FRC_START) >
1282         (s->l_timer[lt_i].reg.tcon & L_TCON_FRC_START)) {
1283             DPRINTF("local timer[%d] start frc\n", lt_i);
1284             exynos4210_lfrc_start(&s->l_timer[lt_i]);
1285         }
1286         if ((value & L_TCON_FRC_START) <
1287                 (s->l_timer[lt_i].reg.tcon & L_TCON_FRC_START)) {
1288             DPRINTF("local timer[%d] stop frc\n", lt_i);
1289             exynos4210_lfrc_stop(&s->l_timer[lt_i]);
1290         }
1291         break;
1292 
1293     case L0_TCNTB: case L1_TCNTB:
1294 
1295         lt_i = GET_L_TIMER_IDX(offset);
1296         index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i);
1297 
1298         /*
1299          * TCNTB is updated to internal register only after CNT expired.
1300          * Due to this we should reload timer to nearest moment when CNT is
1301          * expired and then in event handler update tcntb to new TCNTB value.
1302          */
1303         exynos4210_ltick_set_cntb(&s->l_timer[lt_i].tick_timer, value,
1304                 s->l_timer[lt_i].tick_timer.icntb);
1305 
1306         s->l_timer[lt_i].reg.wstat |= L_WSTAT_TCNTB_WRITE;
1307         s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB] = value;
1308 
1309 #ifdef DEBUG_MCT
1310         if (tcntb_min[lt_i] > value) {
1311             tcntb_min[lt_i] = value;
1312         }
1313         if (tcntb_max[lt_i] < value) {
1314             tcntb_max[lt_i] = value;
1315         }
1316         DPRINTF("local timer[%d] TCNTB write %llx; max=%x, min=%x\n",
1317                 lt_i, value, tcntb_max[lt_i], tcntb_min[lt_i]);
1318 #endif
1319         break;
1320 
1321     case L0_ICNTB: case L1_ICNTB:
1322 
1323         lt_i = GET_L_TIMER_IDX(offset);
1324         index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i);
1325 
1326         s->l_timer[lt_i].reg.wstat |= L_WSTAT_ICNTB_WRITE;
1327         s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] = value &
1328                 ~L_ICNTB_MANUAL_UPDATE;
1329 
1330         /*
1331          * We need to avoid too small values for TCNTB*ICNTB. If not, IRQ event
1332          * could raise too fast disallowing QEMU to execute target code.
1333          */
1334         if (s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] *
1335             s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB] < MCT_LT_CNT_LOW_LIMIT) {
1336             if (!s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB]) {
1337                 s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] =
1338                         MCT_LT_CNT_LOW_LIMIT;
1339             } else {
1340                 s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] =
1341                         MCT_LT_CNT_LOW_LIMIT /
1342                         s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB];
1343             }
1344         }
1345 
1346         if (value & L_ICNTB_MANUAL_UPDATE) {
1347             exynos4210_ltick_set_cntb(&s->l_timer[lt_i].tick_timer,
1348                     s->l_timer[lt_i].tick_timer.tcntb,
1349                     s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB]);
1350         }
1351 
1352 #ifdef DEBUG_MCT
1353         if (icntb_min[lt_i] > value) {
1354             icntb_min[lt_i] = value;
1355         }
1356         if (icntb_max[lt_i] < value) {
1357             icntb_max[lt_i] = value;
1358         }
1359 DPRINTF("local timer[%d] ICNTB write %llx; max=%x, min=%x\n\n",
1360         lt_i, value, icntb_max[lt_i], icntb_min[lt_i]);
1361 #endif
1362 break;
1363 
1364     case L0_FRCNTB: case L1_FRCNTB:
1365 
1366         lt_i = GET_L_TIMER_IDX(offset);
1367         index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i);
1368 
1369         DPRINTF("local timer[%d] FRCNTB write %llx\n", lt_i, value);
1370 
1371         s->l_timer[lt_i].reg.wstat |= L_WSTAT_FRCCNTB_WRITE;
1372         s->l_timer[lt_i].reg.cnt[L_REG_CNT_FRCCNTB] = value;
1373 
1374         break;
1375 
1376     case L0_TCNTO: case L1_TCNTO:
1377     case L0_ICNTO: case L1_ICNTO:
1378     case L0_FRCNTO: case L1_FRCNTO:
1379         fprintf(stderr, "\n[exynos4210.mct: write to RO register "
1380                 TARGET_FMT_plx "]\n\n", offset);
1381         break;
1382 
1383     case L0_INT_CSTAT: case L1_INT_CSTAT:
1384         lt_i = GET_L_TIMER_IDX(offset);
1385 
1386         DPRINTF("local timer[%d] CSTAT write %llx\n", lt_i, value);
1387 
1388         s->l_timer[lt_i].reg.int_cstat &= ~value;
1389         if (!s->l_timer[lt_i].reg.int_cstat) {
1390             qemu_irq_lower(s->l_timer[lt_i].irq);
1391         }
1392         break;
1393 
1394     case L0_INT_ENB: case L1_INT_ENB:
1395         lt_i = GET_L_TIMER_IDX(offset);
1396         old_val = s->l_timer[lt_i].reg.int_enb;
1397 
1398         /* Raise Local timer IRQ if cstat is pending */
1399         if ((value & L_INT_INTENB_ICNTEIE) > (old_val & L_INT_INTENB_ICNTEIE)) {
1400             if (s->l_timer[lt_i].reg.int_cstat & L_INT_CSTAT_INTCNT) {
1401                 qemu_irq_raise(s->l_timer[lt_i].irq);
1402             }
1403         }
1404 
1405         s->l_timer[lt_i].reg.int_enb = value;
1406 
1407         break;
1408 
1409     case L0_WSTAT: case L1_WSTAT:
1410         lt_i = GET_L_TIMER_IDX(offset);
1411 
1412         s->l_timer[lt_i].reg.wstat &= ~value;
1413         break;
1414 
1415     default:
1416         hw_error("exynos4210.mct: bad write offset "
1417                 TARGET_FMT_plx "\n", offset);
1418         break;
1419     }
1420 }
1421 
1422 static const MemoryRegionOps exynos4210_mct_ops = {
1423     .read = exynos4210_mct_read,
1424     .write = exynos4210_mct_write,
1425     .endianness = DEVICE_NATIVE_ENDIAN,
1426 };
1427 
1428 /* MCT init */
1429 static int exynos4210_mct_init(SysBusDevice *dev)
1430 {
1431     int i;
1432     Exynos4210MCTState *s = EXYNOS4210_MCT(dev);
1433     QEMUBH *bh[2];
1434 
1435     /* Global timer */
1436     bh[0] = qemu_bh_new(exynos4210_gfrc_event, s);
1437     s->g_timer.ptimer_frc = ptimer_init(bh[0]);
1438     memset(&s->g_timer.reg, 0, sizeof(struct gregs));
1439 
1440     /* Local timers */
1441     for (i = 0; i < 2; i++) {
1442         bh[0] = qemu_bh_new(exynos4210_ltick_event, &s->l_timer[i]);
1443         bh[1] = qemu_bh_new(exynos4210_lfrc_event, &s->l_timer[i]);
1444         s->l_timer[i].tick_timer.ptimer_tick = ptimer_init(bh[0]);
1445         s->l_timer[i].ptimer_frc = ptimer_init(bh[1]);
1446         s->l_timer[i].id = i;
1447     }
1448 
1449     /* IRQs */
1450     for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1451         sysbus_init_irq(dev, &s->g_timer.irq[i]);
1452     }
1453     for (i = 0; i < 2; i++) {
1454         sysbus_init_irq(dev, &s->l_timer[i].irq);
1455     }
1456 
1457     memory_region_init_io(&s->iomem, OBJECT(s), &exynos4210_mct_ops, s,
1458                           "exynos4210-mct", MCT_SFR_SIZE);
1459     sysbus_init_mmio(dev, &s->iomem);
1460 
1461     return 0;
1462 }
1463 
1464 static void exynos4210_mct_class_init(ObjectClass *klass, void *data)
1465 {
1466     DeviceClass *dc = DEVICE_CLASS(klass);
1467     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
1468 
1469     k->init = exynos4210_mct_init;
1470     dc->reset = exynos4210_mct_reset;
1471     dc->vmsd = &vmstate_exynos4210_mct_state;
1472 }
1473 
1474 static const TypeInfo exynos4210_mct_info = {
1475     .name          = TYPE_EXYNOS4210_MCT,
1476     .parent        = TYPE_SYS_BUS_DEVICE,
1477     .instance_size = sizeof(Exynos4210MCTState),
1478     .class_init    = exynos4210_mct_class_init,
1479 };
1480 
1481 static void exynos4210_mct_register_types(void)
1482 {
1483     type_register_static(&exynos4210_mct_info);
1484 }
1485 
1486 type_init(exynos4210_mct_register_types)
1487