xref: /qemu/hw/timer/exynos4210_mct.c (revision 138ca49a)
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 "qemu/osdep.h"
56 #include "qemu/log.h"
57 #include "hw/sysbus.h"
58 #include "migration/vmstate.h"
59 #include "qemu/timer.h"
60 #include "qemu/module.h"
61 #include "hw/ptimer.h"
62 
63 #include "hw/arm/exynos4210.h"
64 #include "hw/irq.h"
65 #include "qom/object.h"
66 
67 //#define DEBUG_MCT
68 
69 #ifdef DEBUG_MCT
70 #define DPRINTF(fmt, ...) \
71         do { fprintf(stdout, "MCT: [%24s:%5d] " fmt, __func__, __LINE__, \
72                      ## __VA_ARGS__); } while (0)
73 #else
74 #define DPRINTF(fmt, ...) do {} while (0)
75 #endif
76 
77 #define    MCT_CFG          0x000
78 #define    G_CNT_L          0x100
79 #define    G_CNT_U          0x104
80 #define    G_CNT_WSTAT      0x110
81 #define    G_COMP0_L        0x200
82 #define    G_COMP0_U        0x204
83 #define    G_COMP0_ADD_INCR 0x208
84 #define    G_COMP1_L        0x210
85 #define    G_COMP1_U        0x214
86 #define    G_COMP1_ADD_INCR 0x218
87 #define    G_COMP2_L        0x220
88 #define    G_COMP2_U        0x224
89 #define    G_COMP2_ADD_INCR 0x228
90 #define    G_COMP3_L        0x230
91 #define    G_COMP3_U        0x234
92 #define    G_COMP3_ADD_INCR 0x238
93 #define    G_TCON           0x240
94 #define    G_INT_CSTAT      0x244
95 #define    G_INT_ENB        0x248
96 #define    G_WSTAT          0x24C
97 #define    L0_TCNTB         0x300
98 #define    L0_TCNTO         0x304
99 #define    L0_ICNTB         0x308
100 #define    L0_ICNTO         0x30C
101 #define    L0_FRCNTB        0x310
102 #define    L0_FRCNTO        0x314
103 #define    L0_TCON          0x320
104 #define    L0_INT_CSTAT     0x330
105 #define    L0_INT_ENB       0x334
106 #define    L0_WSTAT         0x340
107 #define    L1_TCNTB         0x400
108 #define    L1_TCNTO         0x404
109 #define    L1_ICNTB         0x408
110 #define    L1_ICNTO         0x40C
111 #define    L1_FRCNTB        0x410
112 #define    L1_FRCNTO        0x414
113 #define    L1_TCON          0x420
114 #define    L1_INT_CSTAT     0x430
115 #define    L1_INT_ENB       0x434
116 #define    L1_WSTAT         0x440
117 
118 #define MCT_CFG_GET_PRESCALER(x)    ((x) & 0xFF)
119 #define MCT_CFG_GET_DIVIDER(x)      (1 << ((x) >> 8 & 7))
120 
121 #define GET_G_COMP_IDX(offset)          (((offset) - G_COMP0_L) / 0x10)
122 #define GET_G_COMP_ADD_INCR_IDX(offset) (((offset) - G_COMP0_ADD_INCR) / 0x10)
123 
124 #define G_COMP_L(x) (G_COMP0_L + (x) * 0x10)
125 #define G_COMP_U(x) (G_COMP0_U + (x) * 0x10)
126 
127 #define G_COMP_ADD_INCR(x)  (G_COMP0_ADD_INCR + (x) * 0x10)
128 
129 /* MCT bits */
130 #define G_TCON_COMP_ENABLE(x)   (1 << 2 * (x))
131 #define G_TCON_AUTO_ICREMENT(x) (1 << (2 * (x) + 1))
132 #define G_TCON_TIMER_ENABLE     (1 << 8)
133 
134 #define G_INT_ENABLE(x)         (1 << (x))
135 #define G_INT_CSTAT_COMP(x)     (1 << (x))
136 
137 #define G_CNT_WSTAT_L           1
138 #define G_CNT_WSTAT_U           2
139 
140 #define G_WSTAT_COMP_L(x)       (1 << 4 * (x))
141 #define G_WSTAT_COMP_U(x)       (1 << ((4 * (x)) + 1))
142 #define G_WSTAT_COMP_ADDINCR(x) (1 << ((4 * (x)) + 2))
143 #define G_WSTAT_TCON_WRITE      (1 << 16)
144 
145 #define GET_L_TIMER_IDX(offset) ((((offset) & 0xF00) - L0_TCNTB) / 0x100)
146 #define GET_L_TIMER_CNT_REG_IDX(offset, lt_i) \
147         (((offset) - (L0_TCNTB + 0x100 * (lt_i))) >> 2)
148 
149 #define L_ICNTB_MANUAL_UPDATE   (1 << 31)
150 
151 #define L_TCON_TICK_START       (1)
152 #define L_TCON_INT_START        (1 << 1)
153 #define L_TCON_INTERVAL_MODE    (1 << 2)
154 #define L_TCON_FRC_START        (1 << 3)
155 
156 #define L_INT_CSTAT_INTCNT      (1 << 0)
157 #define L_INT_CSTAT_FRCCNT      (1 << 1)
158 
159 #define L_INT_INTENB_ICNTEIE    (1 << 0)
160 #define L_INT_INTENB_FRCEIE     (1 << 1)
161 
162 #define L_WSTAT_TCNTB_WRITE     (1 << 0)
163 #define L_WSTAT_ICNTB_WRITE     (1 << 1)
164 #define L_WSTAT_FRCCNTB_WRITE   (1 << 2)
165 #define L_WSTAT_TCON_WRITE      (1 << 3)
166 
167 enum LocalTimerRegCntIndexes {
168     L_REG_CNT_TCNTB,
169     L_REG_CNT_TCNTO,
170     L_REG_CNT_ICNTB,
171     L_REG_CNT_ICNTO,
172     L_REG_CNT_FRCCNTB,
173     L_REG_CNT_FRCCNTO,
174 
175     L_REG_CNT_AMOUNT
176 };
177 
178 #define MCT_SFR_SIZE            0x444
179 
180 #define MCT_GT_CMP_NUM          4
181 
182 #define MCT_GT_COUNTER_STEP     0x100000000ULL
183 #define MCT_LT_COUNTER_STEP     0x100000000ULL
184 #define MCT_LT_CNT_LOW_LIMIT    0x100
185 
186 /* global timer */
187 typedef struct {
188     qemu_irq  irq[MCT_GT_CMP_NUM];
189 
190     struct gregs {
191         uint64_t cnt;
192         uint32_t cnt_wstat;
193         uint32_t tcon;
194         uint32_t int_cstat;
195         uint32_t int_enb;
196         uint32_t wstat;
197         uint64_t comp[MCT_GT_CMP_NUM];
198         uint32_t comp_add_incr[MCT_GT_CMP_NUM];
199     } reg;
200 
201     uint64_t count;            /* Value FRC was armed with */
202     int32_t curr_comp;             /* Current comparator FRC is running to */
203 
204     ptimer_state *ptimer_frc;                   /* FRC timer */
205 
206 } Exynos4210MCTGT;
207 
208 /* local timer */
209 typedef struct {
210     int         id;             /* timer id */
211     qemu_irq    irq;            /* local timer irq */
212 
213     struct tick_timer {
214         uint32_t cnt_run;           /* cnt timer is running */
215         uint32_t int_run;           /* int timer is running */
216 
217         uint32_t last_icnto;
218         uint32_t last_tcnto;
219         uint32_t tcntb;             /* initial value for TCNTB */
220         uint32_t icntb;             /* initial value for ICNTB */
221 
222         /* for step mode */
223         uint64_t    distance;       /* distance to count to the next event */
224         uint64_t    progress;       /* progress when counting by steps */
225         uint64_t    count;          /* count to arm timer with */
226 
227         ptimer_state *ptimer_tick;  /* timer for tick counter */
228     } tick_timer;
229 
230     /* use ptimer.c to represent count down timer */
231 
232     ptimer_state *ptimer_frc;   /* timer for free running counter */
233 
234     /* registers */
235     struct lregs {
236         uint32_t    cnt[L_REG_CNT_AMOUNT];
237         uint32_t    tcon;
238         uint32_t    int_cstat;
239         uint32_t    int_enb;
240         uint32_t    wstat;
241     } reg;
242 
243 } Exynos4210MCTLT;
244 
245 #define TYPE_EXYNOS4210_MCT "exynos4210.mct"
246 OBJECT_DECLARE_SIMPLE_TYPE(Exynos4210MCTState, EXYNOS4210_MCT)
247 
248 struct Exynos4210MCTState {
249     SysBusDevice parent_obj;
250 
251     MemoryRegion iomem;
252 
253     /* Registers */
254     uint32_t    reg_mct_cfg;
255 
256     Exynos4210MCTLT l_timer[2];
257     Exynos4210MCTGT g_timer;
258 
259     uint32_t    freq;                   /* all timers tick frequency, TCLK */
260 };
261 
262 /*** VMState ***/
263 static const VMStateDescription vmstate_tick_timer = {
264     .name = "exynos4210.mct.tick_timer",
265     .version_id = 1,
266     .minimum_version_id = 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     .fields = (VMStateField[]) {
287         VMSTATE_UINT32_ARRAY(cnt, struct lregs, L_REG_CNT_AMOUNT),
288         VMSTATE_UINT32(tcon, struct lregs),
289         VMSTATE_UINT32(int_cstat, struct lregs),
290         VMSTATE_UINT32(int_enb, struct lregs),
291         VMSTATE_UINT32(wstat, struct lregs),
292         VMSTATE_END_OF_LIST()
293     }
294 };
295 
296 static const VMStateDescription vmstate_exynos4210_mct_lt = {
297     .name = "exynos4210.mct.lt",
298     .version_id = 1,
299     .minimum_version_id = 1,
300     .fields = (VMStateField[]) {
301         VMSTATE_INT32(id, Exynos4210MCTLT),
302         VMSTATE_STRUCT(tick_timer, Exynos4210MCTLT, 0,
303                 vmstate_tick_timer,
304                 struct tick_timer),
305         VMSTATE_PTIMER(ptimer_frc, Exynos4210MCTLT),
306         VMSTATE_STRUCT(reg, Exynos4210MCTLT, 0,
307                 vmstate_lregs,
308                 struct lregs),
309         VMSTATE_END_OF_LIST()
310     }
311 };
312 
313 static const VMStateDescription vmstate_gregs = {
314     .name = "exynos4210.mct.lregs",
315     .version_id = 1,
316     .minimum_version_id = 1,
317     .fields = (VMStateField[]) {
318         VMSTATE_UINT64(cnt, struct gregs),
319         VMSTATE_UINT32(cnt_wstat, struct gregs),
320         VMSTATE_UINT32(tcon, struct gregs),
321         VMSTATE_UINT32(int_cstat, struct gregs),
322         VMSTATE_UINT32(int_enb, struct gregs),
323         VMSTATE_UINT32(wstat, struct gregs),
324         VMSTATE_UINT64_ARRAY(comp, struct gregs, MCT_GT_CMP_NUM),
325         VMSTATE_UINT32_ARRAY(comp_add_incr, struct gregs,
326                 MCT_GT_CMP_NUM),
327         VMSTATE_END_OF_LIST()
328     }
329 };
330 
331 static const VMStateDescription vmstate_exynos4210_mct_gt = {
332     .name = "exynos4210.mct.lt",
333     .version_id = 1,
334     .minimum_version_id = 1,
335     .fields = (VMStateField[]) {
336         VMSTATE_STRUCT(reg, Exynos4210MCTGT, 0, vmstate_gregs,
337                 struct gregs),
338         VMSTATE_UINT64(count, Exynos4210MCTGT),
339         VMSTATE_INT32(curr_comp, Exynos4210MCTGT),
340         VMSTATE_PTIMER(ptimer_frc, Exynos4210MCTGT),
341         VMSTATE_END_OF_LIST()
342     }
343 };
344 
345 static const VMStateDescription vmstate_exynos4210_mct_state = {
346     .name = "exynos4210.mct",
347     .version_id = 1,
348     .minimum_version_id = 1,
349     .fields = (VMStateField[]) {
350         VMSTATE_UINT32(reg_mct_cfg, Exynos4210MCTState),
351         VMSTATE_STRUCT_ARRAY(l_timer, Exynos4210MCTState, 2, 0,
352             vmstate_exynos4210_mct_lt, Exynos4210MCTLT),
353         VMSTATE_STRUCT(g_timer, Exynos4210MCTState, 0,
354             vmstate_exynos4210_mct_gt, Exynos4210MCTGT),
355         VMSTATE_UINT32(freq, Exynos4210MCTState),
356         VMSTATE_END_OF_LIST()
357     }
358 };
359 
360 static void exynos4210_mct_update_freq(Exynos4210MCTState *s);
361 
362 /*
363  * Set counter of FRC global timer.
364  * Must be called within exynos4210_gfrc_tx_begin/commit block.
365  */
366 static void exynos4210_gfrc_set_count(Exynos4210MCTGT *s, uint64_t count)
367 {
368     s->count = count;
369     DPRINTF("global timer frc set count 0x%llx\n", count);
370     ptimer_set_count(s->ptimer_frc, count);
371 }
372 
373 /*
374  * Get counter of FRC global timer.
375  */
376 static uint64_t exynos4210_gfrc_get_count(Exynos4210MCTGT *s)
377 {
378     uint64_t count = 0;
379     count = ptimer_get_count(s->ptimer_frc);
380     count = s->count - count;
381     return s->reg.cnt + count;
382 }
383 
384 /*
385  * Stop global FRC timer
386  * Must be called within exynos4210_gfrc_tx_begin/commit block.
387  */
388 static void exynos4210_gfrc_stop(Exynos4210MCTGT *s)
389 {
390     DPRINTF("global timer frc stop\n");
391 
392     ptimer_stop(s->ptimer_frc);
393 }
394 
395 /*
396  * Start global FRC timer
397  * Must be called within exynos4210_gfrc_tx_begin/commit block.
398  */
399 static void exynos4210_gfrc_start(Exynos4210MCTGT *s)
400 {
401     DPRINTF("global timer frc start\n");
402 
403     ptimer_run(s->ptimer_frc, 1);
404 }
405 
406 /*
407  * Start ptimer transaction for global FRC timer; this is just for
408  * consistency with the way we wrap operations like stop and run.
409  */
410 static void exynos4210_gfrc_tx_begin(Exynos4210MCTGT *s)
411 {
412     ptimer_transaction_begin(s->ptimer_frc);
413 }
414 
415 /* Commit ptimer transaction for global FRC timer. */
416 static void exynos4210_gfrc_tx_commit(Exynos4210MCTGT *s)
417 {
418     ptimer_transaction_commit(s->ptimer_frc);
419 }
420 
421 /*
422  * Find next nearest Comparator. If current Comparator value equals to other
423  * Comparator value, skip them both
424  */
425 static int32_t exynos4210_gcomp_find(Exynos4210MCTState *s)
426 {
427     int res;
428     int i;
429     int enabled;
430     uint64_t min;
431     int min_comp_i;
432     uint64_t gfrc;
433     uint64_t distance;
434     uint64_t distance_min;
435     int comp_i;
436 
437     /* get gfrc count */
438     gfrc = exynos4210_gfrc_get_count(&s->g_timer);
439 
440     min = UINT64_MAX;
441     distance_min = UINT64_MAX;
442     comp_i = MCT_GT_CMP_NUM;
443     min_comp_i = MCT_GT_CMP_NUM;
444     enabled = 0;
445 
446     /* lookup for nearest comparator */
447     for (i = 0; i < MCT_GT_CMP_NUM; i++) {
448 
449         if (s->g_timer.reg.tcon & G_TCON_COMP_ENABLE(i)) {
450 
451             enabled = 1;
452 
453             if (s->g_timer.reg.comp[i] > gfrc) {
454                 /* Comparator is upper then FRC */
455                 distance = s->g_timer.reg.comp[i] - gfrc;
456 
457                 if (distance <= distance_min) {
458                     distance_min = distance;
459                     comp_i = i;
460                 }
461             } else {
462                 /* Comparator is below FRC, find the smallest */
463 
464                 if (s->g_timer.reg.comp[i] <= min) {
465                     min = s->g_timer.reg.comp[i];
466                     min_comp_i = i;
467                 }
468             }
469         }
470     }
471 
472     if (!enabled) {
473         /* All Comparators disabled */
474         res = -1;
475     } else if (comp_i < MCT_GT_CMP_NUM) {
476         /* Found upper Comparator */
477         res = comp_i;
478     } else {
479         /* All Comparators are below or equal to FRC  */
480         res = min_comp_i;
481     }
482 
483     DPRINTF("found comparator %d: comp 0x%llx distance 0x%llx, gfrc 0x%llx\n",
484             res,
485             s->g_timer.reg.comp[res],
486             distance_min,
487             gfrc);
488 
489     return res;
490 }
491 
492 /*
493  * Get distance to nearest Comparator
494  */
495 static uint64_t exynos4210_gcomp_get_distance(Exynos4210MCTState *s, int32_t id)
496 {
497     if (id == -1) {
498         /* no enabled Comparators, choose max distance */
499         return MCT_GT_COUNTER_STEP;
500     }
501     if (s->g_timer.reg.comp[id] - s->g_timer.reg.cnt < MCT_GT_COUNTER_STEP) {
502         return s->g_timer.reg.comp[id] - s->g_timer.reg.cnt;
503     } else {
504         return MCT_GT_COUNTER_STEP;
505     }
506 }
507 
508 /*
509  * Restart global FRC timer
510  * Must be called within exynos4210_gfrc_tx_begin/commit block.
511  */
512 static void exynos4210_gfrc_restart(Exynos4210MCTState *s)
513 {
514     uint64_t distance;
515 
516     exynos4210_gfrc_stop(&s->g_timer);
517 
518     s->g_timer.curr_comp = exynos4210_gcomp_find(s);
519 
520     distance = exynos4210_gcomp_get_distance(s, s->g_timer.curr_comp);
521 
522     if (distance > MCT_GT_COUNTER_STEP || !distance) {
523         distance = MCT_GT_COUNTER_STEP;
524     }
525 
526     exynos4210_gfrc_set_count(&s->g_timer, distance);
527     exynos4210_gfrc_start(&s->g_timer);
528 }
529 
530 /*
531  * Raise global timer CMP IRQ
532  */
533 static void exynos4210_gcomp_raise_irq(void *opaque, uint32_t id)
534 {
535     Exynos4210MCTGT *s = opaque;
536 
537     /* If CSTAT is pending and IRQ is enabled */
538     if ((s->reg.int_cstat & G_INT_CSTAT_COMP(id)) &&
539             (s->reg.int_enb & G_INT_ENABLE(id))) {
540         DPRINTF("gcmp timer[%u] IRQ\n", id);
541         qemu_irq_raise(s->irq[id]);
542     }
543 }
544 
545 /*
546  * Lower global timer CMP IRQ
547  */
548 static void exynos4210_gcomp_lower_irq(void *opaque, uint32_t id)
549 {
550     Exynos4210MCTGT *s = opaque;
551     qemu_irq_lower(s->irq[id]);
552 }
553 
554 /*
555  * Global timer FRC event handler.
556  * Each event occurs when internal counter reaches counter + MCT_GT_COUNTER_STEP
557  * Every time we arm global FRC timer to count for MCT_GT_COUNTER_STEP value
558  */
559 static void exynos4210_gfrc_event(void *opaque)
560 {
561     Exynos4210MCTState *s = (Exynos4210MCTState *)opaque;
562     int i;
563     uint64_t distance;
564 
565     DPRINTF("\n");
566 
567     s->g_timer.reg.cnt += s->g_timer.count;
568 
569     /* Process all comparators */
570     for (i = 0; i < MCT_GT_CMP_NUM; i++) {
571 
572         if (s->g_timer.reg.cnt == s->g_timer.reg.comp[i]) {
573             /* reached nearest comparator */
574 
575             s->g_timer.reg.int_cstat |= G_INT_CSTAT_COMP(i);
576 
577             /* Auto increment */
578             if (s->g_timer.reg.tcon & G_TCON_AUTO_ICREMENT(i)) {
579                 s->g_timer.reg.comp[i] += s->g_timer.reg.comp_add_incr[i];
580             }
581 
582             /* IRQ */
583             exynos4210_gcomp_raise_irq(&s->g_timer, i);
584         }
585     }
586 
587     /* Reload FRC to reach nearest comparator */
588     s->g_timer.curr_comp = exynos4210_gcomp_find(s);
589     distance = exynos4210_gcomp_get_distance(s, s->g_timer.curr_comp);
590     if (distance > MCT_GT_COUNTER_STEP || !distance) {
591         distance = MCT_GT_COUNTER_STEP;
592     }
593     exynos4210_gfrc_set_count(&s->g_timer, distance);
594 
595     exynos4210_gfrc_start(&s->g_timer);
596 }
597 
598 /*
599  * Get counter of FRC local timer.
600  */
601 static uint64_t exynos4210_lfrc_get_count(Exynos4210MCTLT *s)
602 {
603     return ptimer_get_count(s->ptimer_frc);
604 }
605 
606 /*
607  * Set counter of FRC local timer.
608  * Must be called from within exynos4210_lfrc_tx_begin/commit block.
609  */
610 static void exynos4210_lfrc_update_count(Exynos4210MCTLT *s)
611 {
612     if (!s->reg.cnt[L_REG_CNT_FRCCNTB]) {
613         ptimer_set_count(s->ptimer_frc, MCT_LT_COUNTER_STEP);
614     } else {
615         ptimer_set_count(s->ptimer_frc, s->reg.cnt[L_REG_CNT_FRCCNTB]);
616     }
617 }
618 
619 /*
620  * Start local FRC timer
621  * Must be called from within exynos4210_lfrc_tx_begin/commit block.
622  */
623 static void exynos4210_lfrc_start(Exynos4210MCTLT *s)
624 {
625     ptimer_run(s->ptimer_frc, 1);
626 }
627 
628 /*
629  * Stop local FRC timer
630  * Must be called from within exynos4210_lfrc_tx_begin/commit block.
631  */
632 static void exynos4210_lfrc_stop(Exynos4210MCTLT *s)
633 {
634     ptimer_stop(s->ptimer_frc);
635 }
636 
637 /* Start ptimer transaction for local FRC timer */
638 static void exynos4210_lfrc_tx_begin(Exynos4210MCTLT *s)
639 {
640     ptimer_transaction_begin(s->ptimer_frc);
641 }
642 
643 /* Commit ptimer transaction for local FRC timer */
644 static void exynos4210_lfrc_tx_commit(Exynos4210MCTLT *s)
645 {
646     ptimer_transaction_commit(s->ptimer_frc);
647 }
648 
649 /*
650  * Local timer free running counter tick handler
651  */
652 static void exynos4210_lfrc_event(void *opaque)
653 {
654     Exynos4210MCTLT * s = (Exynos4210MCTLT *)opaque;
655 
656     /* local frc expired */
657 
658     DPRINTF("\n");
659 
660     s->reg.int_cstat |= L_INT_CSTAT_FRCCNT;
661 
662     /* update frc counter */
663     exynos4210_lfrc_update_count(s);
664 
665     /* raise irq */
666     if (s->reg.int_enb & L_INT_INTENB_FRCEIE) {
667         qemu_irq_raise(s->irq);
668     }
669 
670     /*  we reached here, this means that timer is enabled */
671     exynos4210_lfrc_start(s);
672 }
673 
674 static uint32_t exynos4210_ltick_int_get_cnto(struct tick_timer *s);
675 static uint32_t exynos4210_ltick_cnt_get_cnto(struct tick_timer *s);
676 static void exynos4210_ltick_recalc_count(struct tick_timer *s);
677 
678 /*
679  * Action on enabling local tick int timer
680  */
681 static void exynos4210_ltick_int_start(struct tick_timer *s)
682 {
683     if (!s->int_run) {
684         s->int_run = 1;
685     }
686 }
687 
688 /*
689  * Action on disabling local tick int timer
690  */
691 static void exynos4210_ltick_int_stop(struct tick_timer *s)
692 {
693     if (s->int_run) {
694         s->last_icnto = exynos4210_ltick_int_get_cnto(s);
695         s->int_run = 0;
696     }
697 }
698 
699 /*
700  * Get count for INT timer
701  */
702 static uint32_t exynos4210_ltick_int_get_cnto(struct tick_timer *s)
703 {
704     uint32_t icnto;
705     uint64_t remain;
706     uint64_t count;
707     uint64_t counted;
708     uint64_t cur_progress;
709 
710     count = ptimer_get_count(s->ptimer_tick);
711     if (count) {
712         /* timer is still counting, called not from event */
713         counted = s->count - ptimer_get_count(s->ptimer_tick);
714         cur_progress = s->progress + counted;
715     } else {
716         /* timer expired earlier */
717         cur_progress = s->progress;
718     }
719 
720     remain = s->distance - cur_progress;
721 
722     if (!s->int_run) {
723         /* INT is stopped. */
724         icnto = s->last_icnto;
725     } else {
726         /* Both are counting */
727         icnto = remain / s->tcntb;
728     }
729 
730     return icnto;
731 }
732 
733 /*
734  * Start local tick cnt timer.
735  * Must be called within exynos4210_ltick_tx_begin/commit block.
736  */
737 static void exynos4210_ltick_cnt_start(struct tick_timer *s)
738 {
739     if (!s->cnt_run) {
740 
741         exynos4210_ltick_recalc_count(s);
742         ptimer_set_count(s->ptimer_tick, s->count);
743         ptimer_run(s->ptimer_tick, 1);
744 
745         s->cnt_run = 1;
746     }
747 }
748 
749 /*
750  * Stop local tick cnt timer.
751  * Must be called within exynos4210_ltick_tx_begin/commit block.
752  */
753 static void exynos4210_ltick_cnt_stop(struct tick_timer *s)
754 {
755     if (s->cnt_run) {
756 
757         s->last_tcnto = exynos4210_ltick_cnt_get_cnto(s);
758 
759         if (s->int_run) {
760             exynos4210_ltick_int_stop(s);
761         }
762 
763         ptimer_stop(s->ptimer_tick);
764 
765         s->cnt_run = 0;
766     }
767 }
768 
769 /* Start ptimer transaction for local tick timer */
770 static void exynos4210_ltick_tx_begin(struct tick_timer *s)
771 {
772     ptimer_transaction_begin(s->ptimer_tick);
773 }
774 
775 /* Commit ptimer transaction for local tick timer */
776 static void exynos4210_ltick_tx_commit(struct tick_timer *s)
777 {
778     ptimer_transaction_commit(s->ptimer_tick);
779 }
780 
781 /*
782  * Get counter for CNT timer
783  */
784 static uint32_t exynos4210_ltick_cnt_get_cnto(struct tick_timer *s)
785 {
786     uint32_t tcnto;
787     uint32_t icnto;
788     uint64_t remain;
789     uint64_t counted;
790     uint64_t count;
791     uint64_t cur_progress;
792 
793     count = ptimer_get_count(s->ptimer_tick);
794     if (count) {
795         /* timer is still counting, called not from event */
796         counted = s->count - ptimer_get_count(s->ptimer_tick);
797         cur_progress = s->progress + counted;
798     } else {
799         /* timer expired earlier */
800         cur_progress = s->progress;
801     }
802 
803     remain = s->distance - cur_progress;
804 
805     if (!s->cnt_run) {
806         /* Both are stopped. */
807         tcnto = s->last_tcnto;
808     } else if (!s->int_run) {
809         /* INT counter is stopped, progress is by CNT timer */
810         tcnto = remain % s->tcntb;
811     } else {
812         /* Both are counting */
813         icnto = remain / s->tcntb;
814         if (icnto) {
815             tcnto = remain % (icnto * s->tcntb);
816         } else {
817             tcnto = remain % s->tcntb;
818         }
819     }
820 
821     return tcnto;
822 }
823 
824 /*
825  * Set new values of counters for CNT and INT timers
826  * Must be called within exynos4210_ltick_tx_begin/commit block.
827  */
828 static void exynos4210_ltick_set_cntb(struct tick_timer *s, uint32_t new_cnt,
829         uint32_t new_int)
830 {
831     uint32_t cnt_stopped = 0;
832     uint32_t int_stopped = 0;
833 
834     if (s->cnt_run) {
835         exynos4210_ltick_cnt_stop(s);
836         cnt_stopped = 1;
837     }
838 
839     if (s->int_run) {
840         exynos4210_ltick_int_stop(s);
841         int_stopped = 1;
842     }
843 
844     s->tcntb = new_cnt + 1;
845     s->icntb = new_int + 1;
846 
847     if (cnt_stopped) {
848         exynos4210_ltick_cnt_start(s);
849     }
850     if (int_stopped) {
851         exynos4210_ltick_int_start(s);
852     }
853 
854 }
855 
856 /*
857  * Calculate new counter value for tick timer
858  */
859 static void exynos4210_ltick_recalc_count(struct tick_timer *s)
860 {
861     uint64_t to_count;
862 
863     if ((s->cnt_run && s->last_tcnto) || (s->int_run && s->last_icnto)) {
864         /*
865          * one or both timers run and not counted to the end;
866          * distance is not passed, recalculate with last_tcnto * last_icnto
867          */
868 
869         if (s->last_tcnto) {
870             to_count = (uint64_t)s->last_tcnto * s->last_icnto;
871         } else {
872             to_count = s->last_icnto;
873         }
874     } else {
875         /* distance is passed, recalculate with tcnto * icnto */
876         if (s->icntb) {
877             s->distance = (uint64_t)s->tcntb * s->icntb;
878         } else {
879             s->distance = s->tcntb;
880         }
881 
882         to_count = s->distance;
883         s->progress = 0;
884     }
885 
886     if (to_count > MCT_LT_COUNTER_STEP) {
887         /* count by step */
888         s->count = MCT_LT_COUNTER_STEP;
889     } else {
890         s->count = to_count;
891     }
892 }
893 
894 /*
895  * Initialize tick_timer
896  */
897 static void exynos4210_ltick_timer_init(struct tick_timer *s)
898 {
899     exynos4210_ltick_int_stop(s);
900     exynos4210_ltick_tx_begin(s);
901     exynos4210_ltick_cnt_stop(s);
902     exynos4210_ltick_tx_commit(s);
903 
904     s->count = 0;
905     s->distance = 0;
906     s->progress = 0;
907     s->icntb = 0;
908     s->tcntb = 0;
909 }
910 
911 /*
912  * tick_timer event.
913  * Raises when abstract tick_timer expires.
914  */
915 static void exynos4210_ltick_timer_event(struct tick_timer *s)
916 {
917     s->progress += s->count;
918 }
919 
920 /*
921  * Local timer tick counter handler.
922  * Don't use reloaded timers. If timer counter = zero
923  * then handler called but after handler finished no
924  * timer reload occurs.
925  */
926 static void exynos4210_ltick_event(void *opaque)
927 {
928     Exynos4210MCTLT * s = (Exynos4210MCTLT *)opaque;
929     uint32_t tcnto;
930     uint32_t icnto;
931 #ifdef DEBUG_MCT
932     static uint64_t time1[2] = {0};
933     static uint64_t time2[2] = {0};
934 #endif
935 
936     /* Call tick_timer event handler, it will update its tcntb and icntb. */
937     exynos4210_ltick_timer_event(&s->tick_timer);
938 
939     /* get tick_timer cnt */
940     tcnto = exynos4210_ltick_cnt_get_cnto(&s->tick_timer);
941 
942     /* get tick_timer int */
943     icnto = exynos4210_ltick_int_get_cnto(&s->tick_timer);
944 
945     /* raise IRQ if needed */
946     if (!icnto && s->reg.tcon & L_TCON_INT_START) {
947         /* INT counter enabled and expired */
948 
949         s->reg.int_cstat |= L_INT_CSTAT_INTCNT;
950 
951         /* raise interrupt if enabled */
952         if (s->reg.int_enb & L_INT_INTENB_ICNTEIE) {
953 #ifdef DEBUG_MCT
954             time2[s->id] = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
955             DPRINTF("local timer[%d] IRQ: %llx\n", s->id,
956                     time2[s->id] - time1[s->id]);
957             time1[s->id] = time2[s->id];
958 #endif
959             qemu_irq_raise(s->irq);
960         }
961 
962         /* reload ICNTB */
963         if (s->reg.tcon & L_TCON_INTERVAL_MODE) {
964             exynos4210_ltick_set_cntb(&s->tick_timer,
965                     s->reg.cnt[L_REG_CNT_TCNTB],
966                     s->reg.cnt[L_REG_CNT_ICNTB]);
967         }
968     } else {
969         /* reload TCNTB */
970         if (!tcnto) {
971             exynos4210_ltick_set_cntb(&s->tick_timer,
972                     s->reg.cnt[L_REG_CNT_TCNTB],
973                     icnto);
974         }
975     }
976 
977     /* start tick_timer cnt */
978     exynos4210_ltick_cnt_start(&s->tick_timer);
979 
980     /* start tick_timer int */
981     exynos4210_ltick_int_start(&s->tick_timer);
982 }
983 
984 static void tx_ptimer_set_freq(ptimer_state *s, uint32_t freq)
985 {
986     /*
987      * callers of exynos4210_mct_update_freq() never do anything
988      * else that needs to be in the same ptimer transaction, so
989      * to avoid a lot of repetition we have a convenience function
990      * for begin/set_freq/commit.
991      */
992     ptimer_transaction_begin(s);
993     ptimer_set_freq(s, freq);
994     ptimer_transaction_commit(s);
995 }
996 
997 /* update timer frequency */
998 static void exynos4210_mct_update_freq(Exynos4210MCTState *s)
999 {
1000     uint32_t freq = s->freq;
1001     s->freq = 24000000 /
1002             ((MCT_CFG_GET_PRESCALER(s->reg_mct_cfg) + 1) *
1003                     MCT_CFG_GET_DIVIDER(s->reg_mct_cfg));
1004 
1005     if (freq != s->freq) {
1006         DPRINTF("freq=%uHz\n", s->freq);
1007 
1008         /* global timer */
1009         tx_ptimer_set_freq(s->g_timer.ptimer_frc, s->freq);
1010 
1011         /* local timer */
1012         tx_ptimer_set_freq(s->l_timer[0].tick_timer.ptimer_tick, s->freq);
1013         tx_ptimer_set_freq(s->l_timer[0].ptimer_frc, s->freq);
1014         tx_ptimer_set_freq(s->l_timer[1].tick_timer.ptimer_tick, s->freq);
1015         tx_ptimer_set_freq(s->l_timer[1].ptimer_frc, s->freq);
1016     }
1017 }
1018 
1019 /* set defaul_timer values for all fields */
1020 static void exynos4210_mct_reset(DeviceState *d)
1021 {
1022     Exynos4210MCTState *s = EXYNOS4210_MCT(d);
1023     uint32_t i;
1024 
1025     s->reg_mct_cfg = 0;
1026 
1027     /* global timer */
1028     memset(&s->g_timer.reg, 0, sizeof(s->g_timer.reg));
1029     exynos4210_gfrc_tx_begin(&s->g_timer);
1030     exynos4210_gfrc_stop(&s->g_timer);
1031     exynos4210_gfrc_tx_commit(&s->g_timer);
1032 
1033     /* local timer */
1034     memset(s->l_timer[0].reg.cnt, 0, sizeof(s->l_timer[0].reg.cnt));
1035     memset(s->l_timer[1].reg.cnt, 0, sizeof(s->l_timer[1].reg.cnt));
1036     for (i = 0; i < 2; i++) {
1037         s->l_timer[i].reg.int_cstat = 0;
1038         s->l_timer[i].reg.int_enb = 0;
1039         s->l_timer[i].reg.tcon = 0;
1040         s->l_timer[i].reg.wstat = 0;
1041         s->l_timer[i].tick_timer.count = 0;
1042         s->l_timer[i].tick_timer.distance = 0;
1043         s->l_timer[i].tick_timer.progress = 0;
1044         exynos4210_lfrc_tx_begin(&s->l_timer[i]);
1045         ptimer_stop(s->l_timer[i].ptimer_frc);
1046         exynos4210_lfrc_tx_commit(&s->l_timer[i]);
1047 
1048         exynos4210_ltick_timer_init(&s->l_timer[i].tick_timer);
1049     }
1050 
1051     exynos4210_mct_update_freq(s);
1052 
1053 }
1054 
1055 /* Multi Core Timer read */
1056 static uint64_t exynos4210_mct_read(void *opaque, hwaddr offset,
1057         unsigned size)
1058 {
1059     Exynos4210MCTState *s = (Exynos4210MCTState *)opaque;
1060     int index;
1061     int shift;
1062     uint64_t count;
1063     uint32_t value = 0;
1064     int lt_i;
1065 
1066     switch (offset) {
1067 
1068     case MCT_CFG:
1069         value = s->reg_mct_cfg;
1070         break;
1071 
1072     case G_CNT_L: case G_CNT_U:
1073         shift = 8 * (offset & 0x4);
1074         count = exynos4210_gfrc_get_count(&s->g_timer);
1075         value = UINT32_MAX & (count >> shift);
1076         DPRINTF("read FRC=0x%llx\n", count);
1077         break;
1078 
1079     case G_CNT_WSTAT:
1080         value = s->g_timer.reg.cnt_wstat;
1081         break;
1082 
1083     case G_COMP_L(0): case G_COMP_L(1): case G_COMP_L(2): case G_COMP_L(3):
1084     case G_COMP_U(0): case G_COMP_U(1): case G_COMP_U(2): case G_COMP_U(3):
1085         index = GET_G_COMP_IDX(offset);
1086         shift = 8 * (offset & 0x4);
1087         value = UINT32_MAX & (s->g_timer.reg.comp[index] >> shift);
1088     break;
1089 
1090     case G_TCON:
1091         value = s->g_timer.reg.tcon;
1092         break;
1093 
1094     case G_INT_CSTAT:
1095         value = s->g_timer.reg.int_cstat;
1096         break;
1097 
1098     case G_INT_ENB:
1099         value = s->g_timer.reg.int_enb;
1100         break;
1101     case G_WSTAT:
1102         value = s->g_timer.reg.wstat;
1103         break;
1104 
1105     case G_COMP0_ADD_INCR: case G_COMP1_ADD_INCR:
1106     case G_COMP2_ADD_INCR: case G_COMP3_ADD_INCR:
1107         value = s->g_timer.reg.comp_add_incr[GET_G_COMP_ADD_INCR_IDX(offset)];
1108         break;
1109 
1110         /* Local timers */
1111     case L0_TCNTB: case L0_ICNTB: case L0_FRCNTB:
1112     case L1_TCNTB: case L1_ICNTB: case L1_FRCNTB:
1113         lt_i = GET_L_TIMER_IDX(offset);
1114         index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i);
1115         value = s->l_timer[lt_i].reg.cnt[index];
1116         break;
1117 
1118     case L0_TCNTO: case L1_TCNTO:
1119         lt_i = GET_L_TIMER_IDX(offset);
1120 
1121         value = exynos4210_ltick_cnt_get_cnto(&s->l_timer[lt_i].tick_timer);
1122         DPRINTF("local timer[%d] read TCNTO %x\n", lt_i, value);
1123         break;
1124 
1125     case L0_ICNTO: case L1_ICNTO:
1126         lt_i = GET_L_TIMER_IDX(offset);
1127 
1128         value = exynos4210_ltick_int_get_cnto(&s->l_timer[lt_i].tick_timer);
1129         DPRINTF("local timer[%d] read ICNTO %x\n", lt_i, value);
1130         break;
1131 
1132     case L0_FRCNTO: case L1_FRCNTO:
1133         lt_i = GET_L_TIMER_IDX(offset);
1134 
1135         value = exynos4210_lfrc_get_count(&s->l_timer[lt_i]);
1136         break;
1137 
1138     case L0_TCON: case L1_TCON:
1139         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1140         value = s->l_timer[lt_i].reg.tcon;
1141         break;
1142 
1143     case L0_INT_CSTAT: case L1_INT_CSTAT:
1144         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1145         value = s->l_timer[lt_i].reg.int_cstat;
1146         break;
1147 
1148     case L0_INT_ENB: case L1_INT_ENB:
1149         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1150         value = s->l_timer[lt_i].reg.int_enb;
1151         break;
1152 
1153     case L0_WSTAT: case L1_WSTAT:
1154         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1155         value = s->l_timer[lt_i].reg.wstat;
1156         break;
1157 
1158     default:
1159         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIX "\n",
1160                       __func__, offset);
1161         break;
1162     }
1163     return value;
1164 }
1165 
1166 /* MCT write */
1167 static void exynos4210_mct_write(void *opaque, hwaddr offset,
1168         uint64_t value, unsigned size)
1169 {
1170     Exynos4210MCTState *s = (Exynos4210MCTState *)opaque;
1171     int index;  /* index in buffer which represents register set */
1172     int shift;
1173     int lt_i;
1174     uint64_t new_frc;
1175     uint32_t i;
1176     uint32_t old_val;
1177 #ifdef DEBUG_MCT
1178     static uint32_t icntb_max[2] = {0};
1179     static uint32_t icntb_min[2] = {UINT32_MAX, UINT32_MAX};
1180     static uint32_t tcntb_max[2] = {0};
1181     static uint32_t tcntb_min[2] = {UINT32_MAX, UINT32_MAX};
1182 #endif
1183 
1184     new_frc = s->g_timer.reg.cnt;
1185 
1186     switch (offset) {
1187 
1188     case MCT_CFG:
1189         s->reg_mct_cfg = value;
1190         exynos4210_mct_update_freq(s);
1191         break;
1192 
1193     case G_CNT_L:
1194     case G_CNT_U:
1195         if (offset == G_CNT_L) {
1196 
1197             DPRINTF("global timer write to reg.cntl %llx\n", value);
1198 
1199             new_frc = (s->g_timer.reg.cnt & (uint64_t)UINT32_MAX << 32) + value;
1200             s->g_timer.reg.cnt_wstat |= G_CNT_WSTAT_L;
1201         }
1202         if (offset == G_CNT_U) {
1203 
1204             DPRINTF("global timer write to reg.cntu %llx\n", value);
1205 
1206             new_frc = (s->g_timer.reg.cnt & UINT32_MAX) +
1207                     ((uint64_t)value << 32);
1208             s->g_timer.reg.cnt_wstat |= G_CNT_WSTAT_U;
1209         }
1210 
1211         s->g_timer.reg.cnt = new_frc;
1212         exynos4210_gfrc_tx_begin(&s->g_timer);
1213         exynos4210_gfrc_restart(s);
1214         exynos4210_gfrc_tx_commit(&s->g_timer);
1215         break;
1216 
1217     case G_CNT_WSTAT:
1218         s->g_timer.reg.cnt_wstat &= ~(value);
1219         break;
1220 
1221     case G_COMP_L(0): case G_COMP_L(1): case G_COMP_L(2): case G_COMP_L(3):
1222     case G_COMP_U(0): case G_COMP_U(1): case G_COMP_U(2): case G_COMP_U(3):
1223         index = GET_G_COMP_IDX(offset);
1224         shift = 8 * (offset & 0x4);
1225         s->g_timer.reg.comp[index] =
1226                 (s->g_timer.reg.comp[index] &
1227                 (((uint64_t)UINT32_MAX << 32) >> shift)) +
1228                 (value << shift);
1229 
1230         DPRINTF("comparator %d write 0x%llx val << %d\n", index, value, shift);
1231 
1232         if (offset & 0x4) {
1233             s->g_timer.reg.wstat |= G_WSTAT_COMP_U(index);
1234         } else {
1235             s->g_timer.reg.wstat |= G_WSTAT_COMP_L(index);
1236         }
1237 
1238         exynos4210_gfrc_tx_begin(&s->g_timer);
1239         exynos4210_gfrc_restart(s);
1240         exynos4210_gfrc_tx_commit(&s->g_timer);
1241         break;
1242 
1243     case G_TCON:
1244         old_val = s->g_timer.reg.tcon;
1245         s->g_timer.reg.tcon = value;
1246         s->g_timer.reg.wstat |= G_WSTAT_TCON_WRITE;
1247 
1248         DPRINTF("global timer write to reg.g_tcon %llx\n", value);
1249 
1250         exynos4210_gfrc_tx_begin(&s->g_timer);
1251 
1252         /* Start FRC if transition from disabled to enabled */
1253         if ((value & G_TCON_TIMER_ENABLE) > (old_val &
1254                 G_TCON_TIMER_ENABLE)) {
1255             exynos4210_gfrc_restart(s);
1256         }
1257         if ((value & G_TCON_TIMER_ENABLE) < (old_val &
1258                 G_TCON_TIMER_ENABLE)) {
1259             exynos4210_gfrc_stop(&s->g_timer);
1260         }
1261 
1262         /* Start CMP if transition from disabled to enabled */
1263         for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1264             if ((value & G_TCON_COMP_ENABLE(i)) != (old_val &
1265                     G_TCON_COMP_ENABLE(i))) {
1266                 exynos4210_gfrc_restart(s);
1267             }
1268         }
1269 
1270         exynos4210_gfrc_tx_commit(&s->g_timer);
1271         break;
1272 
1273     case G_INT_CSTAT:
1274         s->g_timer.reg.int_cstat &= ~(value);
1275         for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1276             if (value & G_INT_CSTAT_COMP(i)) {
1277                 exynos4210_gcomp_lower_irq(&s->g_timer, i);
1278             }
1279         }
1280         break;
1281 
1282     case G_INT_ENB:
1283         /* Raise IRQ if transition from disabled to enabled and CSTAT pending */
1284         for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1285             if ((value & G_INT_ENABLE(i)) > (s->g_timer.reg.tcon &
1286                     G_INT_ENABLE(i))) {
1287                 if (s->g_timer.reg.int_cstat & G_INT_CSTAT_COMP(i)) {
1288                     exynos4210_gcomp_raise_irq(&s->g_timer, i);
1289                 }
1290             }
1291 
1292             if ((value & G_INT_ENABLE(i)) < (s->g_timer.reg.tcon &
1293                     G_INT_ENABLE(i))) {
1294                 exynos4210_gcomp_lower_irq(&s->g_timer, i);
1295             }
1296         }
1297 
1298         DPRINTF("global timer INT enable %llx\n", value);
1299         s->g_timer.reg.int_enb = value;
1300         break;
1301 
1302     case G_WSTAT:
1303         s->g_timer.reg.wstat &= ~(value);
1304         break;
1305 
1306     case G_COMP0_ADD_INCR: case G_COMP1_ADD_INCR:
1307     case G_COMP2_ADD_INCR: case G_COMP3_ADD_INCR:
1308         index = GET_G_COMP_ADD_INCR_IDX(offset);
1309         s->g_timer.reg.comp_add_incr[index] = value;
1310         s->g_timer.reg.wstat |= G_WSTAT_COMP_ADDINCR(index);
1311         break;
1312 
1313         /* Local timers */
1314     case L0_TCON: case L1_TCON:
1315         lt_i = GET_L_TIMER_IDX(offset);
1316         old_val = s->l_timer[lt_i].reg.tcon;
1317 
1318         s->l_timer[lt_i].reg.wstat |= L_WSTAT_TCON_WRITE;
1319         s->l_timer[lt_i].reg.tcon = value;
1320 
1321         exynos4210_ltick_tx_begin(&s->l_timer[lt_i].tick_timer);
1322         /* Stop local CNT */
1323         if ((value & L_TCON_TICK_START) <
1324                 (old_val & L_TCON_TICK_START)) {
1325             DPRINTF("local timer[%d] stop cnt\n", lt_i);
1326             exynos4210_ltick_cnt_stop(&s->l_timer[lt_i].tick_timer);
1327         }
1328 
1329         /* Stop local INT */
1330         if ((value & L_TCON_INT_START) <
1331                 (old_val & L_TCON_INT_START)) {
1332             DPRINTF("local timer[%d] stop int\n", lt_i);
1333             exynos4210_ltick_int_stop(&s->l_timer[lt_i].tick_timer);
1334         }
1335 
1336         /* Start local CNT */
1337         if ((value & L_TCON_TICK_START) >
1338         (old_val & L_TCON_TICK_START)) {
1339             DPRINTF("local timer[%d] start cnt\n", lt_i);
1340             exynos4210_ltick_cnt_start(&s->l_timer[lt_i].tick_timer);
1341         }
1342 
1343         /* Start local INT */
1344         if ((value & L_TCON_INT_START) >
1345         (old_val & L_TCON_INT_START)) {
1346             DPRINTF("local timer[%d] start int\n", lt_i);
1347             exynos4210_ltick_int_start(&s->l_timer[lt_i].tick_timer);
1348         }
1349         exynos4210_ltick_tx_commit(&s->l_timer[lt_i].tick_timer);
1350 
1351         /* Start or Stop local FRC if TCON changed */
1352         exynos4210_lfrc_tx_begin(&s->l_timer[lt_i]);
1353         if ((value & L_TCON_FRC_START) >
1354         (s->l_timer[lt_i].reg.tcon & L_TCON_FRC_START)) {
1355             DPRINTF("local timer[%d] start frc\n", lt_i);
1356             exynos4210_lfrc_start(&s->l_timer[lt_i]);
1357         }
1358         if ((value & L_TCON_FRC_START) <
1359                 (s->l_timer[lt_i].reg.tcon & L_TCON_FRC_START)) {
1360             DPRINTF("local timer[%d] stop frc\n", lt_i);
1361             exynos4210_lfrc_stop(&s->l_timer[lt_i]);
1362         }
1363         exynos4210_lfrc_tx_commit(&s->l_timer[lt_i]);
1364         break;
1365 
1366     case L0_TCNTB: case L1_TCNTB:
1367         lt_i = GET_L_TIMER_IDX(offset);
1368 
1369         /*
1370          * TCNTB is updated to internal register only after CNT expired.
1371          * Due to this we should reload timer to nearest moment when CNT is
1372          * expired and then in event handler update tcntb to new TCNTB value.
1373          */
1374         exynos4210_ltick_tx_begin(&s->l_timer[lt_i].tick_timer);
1375         exynos4210_ltick_set_cntb(&s->l_timer[lt_i].tick_timer, value,
1376                 s->l_timer[lt_i].tick_timer.icntb);
1377         exynos4210_ltick_tx_commit(&s->l_timer[lt_i].tick_timer);
1378 
1379         s->l_timer[lt_i].reg.wstat |= L_WSTAT_TCNTB_WRITE;
1380         s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB] = value;
1381 
1382 #ifdef DEBUG_MCT
1383         if (tcntb_min[lt_i] > value) {
1384             tcntb_min[lt_i] = value;
1385         }
1386         if (tcntb_max[lt_i] < value) {
1387             tcntb_max[lt_i] = value;
1388         }
1389         DPRINTF("local timer[%d] TCNTB write %llx; max=%x, min=%x\n",
1390                 lt_i, value, tcntb_max[lt_i], tcntb_min[lt_i]);
1391 #endif
1392         break;
1393 
1394     case L0_ICNTB: case L1_ICNTB:
1395         lt_i = GET_L_TIMER_IDX(offset);
1396 
1397         s->l_timer[lt_i].reg.wstat |= L_WSTAT_ICNTB_WRITE;
1398         s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] = value &
1399                 ~L_ICNTB_MANUAL_UPDATE;
1400 
1401         /*
1402          * We need to avoid too small values for TCNTB*ICNTB. If not, IRQ event
1403          * could raise too fast disallowing QEMU to execute target code.
1404          */
1405         if (s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] *
1406             s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB] < MCT_LT_CNT_LOW_LIMIT) {
1407             if (!s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB]) {
1408                 s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] =
1409                         MCT_LT_CNT_LOW_LIMIT;
1410             } else {
1411                 s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] =
1412                         MCT_LT_CNT_LOW_LIMIT /
1413                         s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB];
1414             }
1415         }
1416 
1417         if (value & L_ICNTB_MANUAL_UPDATE) {
1418             exynos4210_ltick_set_cntb(&s->l_timer[lt_i].tick_timer,
1419                     s->l_timer[lt_i].tick_timer.tcntb,
1420                     s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB]);
1421         }
1422 
1423 #ifdef DEBUG_MCT
1424         if (icntb_min[lt_i] > value) {
1425             icntb_min[lt_i] = value;
1426         }
1427         if (icntb_max[lt_i] < value) {
1428             icntb_max[lt_i] = value;
1429         }
1430         DPRINTF("local timer[%d] ICNTB write %llx; max=%x, min=%x\n\n",
1431                 lt_i, value, icntb_max[lt_i], icntb_min[lt_i]);
1432 #endif
1433         break;
1434 
1435     case L0_FRCNTB: case L1_FRCNTB:
1436         lt_i = GET_L_TIMER_IDX(offset);
1437         DPRINTF("local timer[%d] FRCNTB write %llx\n", lt_i, value);
1438 
1439         s->l_timer[lt_i].reg.wstat |= L_WSTAT_FRCCNTB_WRITE;
1440         s->l_timer[lt_i].reg.cnt[L_REG_CNT_FRCCNTB] = value;
1441 
1442         break;
1443 
1444     case L0_TCNTO: case L1_TCNTO:
1445     case L0_ICNTO: case L1_ICNTO:
1446     case L0_FRCNTO: case L1_FRCNTO:
1447         qemu_log_mask(LOG_GUEST_ERROR,
1448                       "exynos4210.mct: write to RO register " TARGET_FMT_plx,
1449                       offset);
1450         break;
1451 
1452     case L0_INT_CSTAT: case L1_INT_CSTAT:
1453         lt_i = GET_L_TIMER_IDX(offset);
1454 
1455         DPRINTF("local timer[%d] CSTAT write %llx\n", lt_i, value);
1456 
1457         s->l_timer[lt_i].reg.int_cstat &= ~value;
1458         if (!s->l_timer[lt_i].reg.int_cstat) {
1459             qemu_irq_lower(s->l_timer[lt_i].irq);
1460         }
1461         break;
1462 
1463     case L0_INT_ENB: case L1_INT_ENB:
1464         lt_i = GET_L_TIMER_IDX(offset);
1465         old_val = s->l_timer[lt_i].reg.int_enb;
1466 
1467         /* Raise Local timer IRQ if cstat is pending */
1468         if ((value & L_INT_INTENB_ICNTEIE) > (old_val & L_INT_INTENB_ICNTEIE)) {
1469             if (s->l_timer[lt_i].reg.int_cstat & L_INT_CSTAT_INTCNT) {
1470                 qemu_irq_raise(s->l_timer[lt_i].irq);
1471             }
1472         }
1473 
1474         s->l_timer[lt_i].reg.int_enb = value;
1475 
1476         break;
1477 
1478     case L0_WSTAT: case L1_WSTAT:
1479         lt_i = GET_L_TIMER_IDX(offset);
1480 
1481         s->l_timer[lt_i].reg.wstat &= ~value;
1482         break;
1483 
1484     default:
1485         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIX "\n",
1486                       __func__, offset);
1487         break;
1488     }
1489 }
1490 
1491 static const MemoryRegionOps exynos4210_mct_ops = {
1492     .read = exynos4210_mct_read,
1493     .write = exynos4210_mct_write,
1494     .endianness = DEVICE_NATIVE_ENDIAN,
1495 };
1496 
1497 /* MCT init */
1498 static void exynos4210_mct_init(Object *obj)
1499 {
1500     int i;
1501     Exynos4210MCTState *s = EXYNOS4210_MCT(obj);
1502     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
1503 
1504     /* Global timer */
1505     s->g_timer.ptimer_frc = ptimer_init(exynos4210_gfrc_event, s,
1506                                         PTIMER_POLICY_DEFAULT);
1507     memset(&s->g_timer.reg, 0, sizeof(struct gregs));
1508 
1509     /* Local timers */
1510     for (i = 0; i < 2; i++) {
1511         s->l_timer[i].tick_timer.ptimer_tick =
1512             ptimer_init(exynos4210_ltick_event, &s->l_timer[i],
1513                         PTIMER_POLICY_DEFAULT);
1514         s->l_timer[i].ptimer_frc =
1515             ptimer_init(exynos4210_lfrc_event, &s->l_timer[i],
1516                         PTIMER_POLICY_DEFAULT);
1517         s->l_timer[i].id = i;
1518     }
1519 
1520     /* IRQs */
1521     for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1522         sysbus_init_irq(dev, &s->g_timer.irq[i]);
1523     }
1524     for (i = 0; i < 2; i++) {
1525         sysbus_init_irq(dev, &s->l_timer[i].irq);
1526     }
1527 
1528     memory_region_init_io(&s->iomem, obj, &exynos4210_mct_ops, s,
1529                           "exynos4210-mct", MCT_SFR_SIZE);
1530     sysbus_init_mmio(dev, &s->iomem);
1531 }
1532 
1533 static void exynos4210_mct_finalize(Object *obj)
1534 {
1535     int i;
1536     Exynos4210MCTState *s = EXYNOS4210_MCT(obj);
1537 
1538     ptimer_free(s->g_timer.ptimer_frc);
1539 
1540     for (i = 0; i < 2; i++) {
1541         ptimer_free(s->l_timer[i].tick_timer.ptimer_tick);
1542         ptimer_free(s->l_timer[i].ptimer_frc);
1543     }
1544 }
1545 
1546 static void exynos4210_mct_class_init(ObjectClass *klass, void *data)
1547 {
1548     DeviceClass *dc = DEVICE_CLASS(klass);
1549 
1550     dc->reset = exynos4210_mct_reset;
1551     dc->vmsd = &vmstate_exynos4210_mct_state;
1552 }
1553 
1554 static const TypeInfo exynos4210_mct_info = {
1555     .name          = TYPE_EXYNOS4210_MCT,
1556     .parent        = TYPE_SYS_BUS_DEVICE,
1557     .instance_size = sizeof(Exynos4210MCTState),
1558     .instance_init = exynos4210_mct_init,
1559     .instance_finalize = exynos4210_mct_finalize,
1560     .class_init    = exynos4210_mct_class_init,
1561 };
1562 
1563 static void exynos4210_mct_register_types(void)
1564 {
1565     type_register_static(&exynos4210_mct_info);
1566 }
1567 
1568 type_init(exynos4210_mct_register_types)
1569