xref: /openbmc/qemu/hw/timer/exynos4210_mct.c (revision e61c4d87)
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     if (res >= 0) {
484         DPRINTF("found comparator %d: "
485                 "comp 0x%llx distance 0x%llx, gfrc 0x%llx\n",
486                 res,
487                 s->g_timer.reg.comp[res],
488                 distance_min,
489                 gfrc);
490     }
491 
492     return res;
493 }
494 
495 /*
496  * Get distance to nearest Comparator
497  */
498 static uint64_t exynos4210_gcomp_get_distance(Exynos4210MCTState *s, int32_t id)
499 {
500     if (id == -1) {
501         /* no enabled Comparators, choose max distance */
502         return MCT_GT_COUNTER_STEP;
503     }
504     if (s->g_timer.reg.comp[id] - s->g_timer.reg.cnt < MCT_GT_COUNTER_STEP) {
505         return s->g_timer.reg.comp[id] - s->g_timer.reg.cnt;
506     } else {
507         return MCT_GT_COUNTER_STEP;
508     }
509 }
510 
511 /*
512  * Restart global FRC timer
513  * Must be called within exynos4210_gfrc_tx_begin/commit block.
514  */
515 static void exynos4210_gfrc_restart(Exynos4210MCTState *s)
516 {
517     uint64_t distance;
518 
519     exynos4210_gfrc_stop(&s->g_timer);
520 
521     s->g_timer.curr_comp = exynos4210_gcomp_find(s);
522 
523     distance = exynos4210_gcomp_get_distance(s, s->g_timer.curr_comp);
524 
525     if (distance > MCT_GT_COUNTER_STEP || !distance) {
526         distance = MCT_GT_COUNTER_STEP;
527     }
528 
529     exynos4210_gfrc_set_count(&s->g_timer, distance);
530     exynos4210_gfrc_start(&s->g_timer);
531 }
532 
533 /*
534  * Raise global timer CMP IRQ
535  */
536 static void exynos4210_gcomp_raise_irq(void *opaque, uint32_t id)
537 {
538     Exynos4210MCTGT *s = opaque;
539 
540     /* If CSTAT is pending and IRQ is enabled */
541     if ((s->reg.int_cstat & G_INT_CSTAT_COMP(id)) &&
542             (s->reg.int_enb & G_INT_ENABLE(id))) {
543         DPRINTF("gcmp timer[%u] IRQ\n", id);
544         qemu_irq_raise(s->irq[id]);
545     }
546 }
547 
548 /*
549  * Lower global timer CMP IRQ
550  */
551 static void exynos4210_gcomp_lower_irq(void *opaque, uint32_t id)
552 {
553     Exynos4210MCTGT *s = opaque;
554     qemu_irq_lower(s->irq[id]);
555 }
556 
557 /*
558  * Global timer FRC event handler.
559  * Each event occurs when internal counter reaches counter + MCT_GT_COUNTER_STEP
560  * Every time we arm global FRC timer to count for MCT_GT_COUNTER_STEP value
561  */
562 static void exynos4210_gfrc_event(void *opaque)
563 {
564     Exynos4210MCTState *s = (Exynos4210MCTState *)opaque;
565     int i;
566     uint64_t distance;
567 
568     DPRINTF("\n");
569 
570     s->g_timer.reg.cnt += s->g_timer.count;
571 
572     /* Process all comparators */
573     for (i = 0; i < MCT_GT_CMP_NUM; i++) {
574 
575         if (s->g_timer.reg.cnt == s->g_timer.reg.comp[i]) {
576             /* reached nearest comparator */
577 
578             s->g_timer.reg.int_cstat |= G_INT_CSTAT_COMP(i);
579 
580             /* Auto increment */
581             if (s->g_timer.reg.tcon & G_TCON_AUTO_ICREMENT(i)) {
582                 s->g_timer.reg.comp[i] += s->g_timer.reg.comp_add_incr[i];
583             }
584 
585             /* IRQ */
586             exynos4210_gcomp_raise_irq(&s->g_timer, i);
587         }
588     }
589 
590     /* Reload FRC to reach nearest comparator */
591     s->g_timer.curr_comp = exynos4210_gcomp_find(s);
592     distance = exynos4210_gcomp_get_distance(s, s->g_timer.curr_comp);
593     if (distance > MCT_GT_COUNTER_STEP || !distance) {
594         distance = MCT_GT_COUNTER_STEP;
595     }
596     exynos4210_gfrc_set_count(&s->g_timer, distance);
597 
598     exynos4210_gfrc_start(&s->g_timer);
599 }
600 
601 /*
602  * Get counter of FRC local timer.
603  */
604 static uint64_t exynos4210_lfrc_get_count(Exynos4210MCTLT *s)
605 {
606     return ptimer_get_count(s->ptimer_frc);
607 }
608 
609 /*
610  * Set counter of FRC local timer.
611  * Must be called from within exynos4210_lfrc_tx_begin/commit block.
612  */
613 static void exynos4210_lfrc_update_count(Exynos4210MCTLT *s)
614 {
615     if (!s->reg.cnt[L_REG_CNT_FRCCNTB]) {
616         ptimer_set_count(s->ptimer_frc, MCT_LT_COUNTER_STEP);
617     } else {
618         ptimer_set_count(s->ptimer_frc, s->reg.cnt[L_REG_CNT_FRCCNTB]);
619     }
620 }
621 
622 /*
623  * Start local FRC timer
624  * Must be called from within exynos4210_lfrc_tx_begin/commit block.
625  */
626 static void exynos4210_lfrc_start(Exynos4210MCTLT *s)
627 {
628     ptimer_run(s->ptimer_frc, 1);
629 }
630 
631 /*
632  * Stop local FRC timer
633  * Must be called from within exynos4210_lfrc_tx_begin/commit block.
634  */
635 static void exynos4210_lfrc_stop(Exynos4210MCTLT *s)
636 {
637     ptimer_stop(s->ptimer_frc);
638 }
639 
640 /* Start ptimer transaction for local FRC timer */
641 static void exynos4210_lfrc_tx_begin(Exynos4210MCTLT *s)
642 {
643     ptimer_transaction_begin(s->ptimer_frc);
644 }
645 
646 /* Commit ptimer transaction for local FRC timer */
647 static void exynos4210_lfrc_tx_commit(Exynos4210MCTLT *s)
648 {
649     ptimer_transaction_commit(s->ptimer_frc);
650 }
651 
652 /*
653  * Local timer free running counter tick handler
654  */
655 static void exynos4210_lfrc_event(void *opaque)
656 {
657     Exynos4210MCTLT * s = (Exynos4210MCTLT *)opaque;
658 
659     /* local frc expired */
660 
661     DPRINTF("\n");
662 
663     s->reg.int_cstat |= L_INT_CSTAT_FRCCNT;
664 
665     /* update frc counter */
666     exynos4210_lfrc_update_count(s);
667 
668     /* raise irq */
669     if (s->reg.int_enb & L_INT_INTENB_FRCEIE) {
670         qemu_irq_raise(s->irq);
671     }
672 
673     /*  we reached here, this means that timer is enabled */
674     exynos4210_lfrc_start(s);
675 }
676 
677 static uint32_t exynos4210_ltick_int_get_cnto(struct tick_timer *s);
678 static uint32_t exynos4210_ltick_cnt_get_cnto(struct tick_timer *s);
679 static void exynos4210_ltick_recalc_count(struct tick_timer *s);
680 
681 /*
682  * Action on enabling local tick int timer
683  */
684 static void exynos4210_ltick_int_start(struct tick_timer *s)
685 {
686     if (!s->int_run) {
687         s->int_run = 1;
688     }
689 }
690 
691 /*
692  * Action on disabling local tick int timer
693  */
694 static void exynos4210_ltick_int_stop(struct tick_timer *s)
695 {
696     if (s->int_run) {
697         s->last_icnto = exynos4210_ltick_int_get_cnto(s);
698         s->int_run = 0;
699     }
700 }
701 
702 /*
703  * Get count for INT timer
704  */
705 static uint32_t exynos4210_ltick_int_get_cnto(struct tick_timer *s)
706 {
707     uint32_t icnto;
708     uint64_t remain;
709     uint64_t count;
710     uint64_t counted;
711     uint64_t cur_progress;
712 
713     count = ptimer_get_count(s->ptimer_tick);
714     if (count) {
715         /* timer is still counting, called not from event */
716         counted = s->count - ptimer_get_count(s->ptimer_tick);
717         cur_progress = s->progress + counted;
718     } else {
719         /* timer expired earlier */
720         cur_progress = s->progress;
721     }
722 
723     remain = s->distance - cur_progress;
724 
725     if (!s->int_run) {
726         /* INT is stopped. */
727         icnto = s->last_icnto;
728     } else {
729         /* Both are counting */
730         icnto = remain / s->tcntb;
731     }
732 
733     return icnto;
734 }
735 
736 /*
737  * Start local tick cnt timer.
738  * Must be called within exynos4210_ltick_tx_begin/commit block.
739  */
740 static void exynos4210_ltick_cnt_start(struct tick_timer *s)
741 {
742     if (!s->cnt_run) {
743 
744         exynos4210_ltick_recalc_count(s);
745         ptimer_set_count(s->ptimer_tick, s->count);
746         ptimer_run(s->ptimer_tick, 1);
747 
748         s->cnt_run = 1;
749     }
750 }
751 
752 /*
753  * Stop local tick cnt timer.
754  * Must be called within exynos4210_ltick_tx_begin/commit block.
755  */
756 static void exynos4210_ltick_cnt_stop(struct tick_timer *s)
757 {
758     if (s->cnt_run) {
759 
760         s->last_tcnto = exynos4210_ltick_cnt_get_cnto(s);
761 
762         if (s->int_run) {
763             exynos4210_ltick_int_stop(s);
764         }
765 
766         ptimer_stop(s->ptimer_tick);
767 
768         s->cnt_run = 0;
769     }
770 }
771 
772 /* Start ptimer transaction for local tick timer */
773 static void exynos4210_ltick_tx_begin(struct tick_timer *s)
774 {
775     ptimer_transaction_begin(s->ptimer_tick);
776 }
777 
778 /* Commit ptimer transaction for local tick timer */
779 static void exynos4210_ltick_tx_commit(struct tick_timer *s)
780 {
781     ptimer_transaction_commit(s->ptimer_tick);
782 }
783 
784 /*
785  * Get counter for CNT timer
786  */
787 static uint32_t exynos4210_ltick_cnt_get_cnto(struct tick_timer *s)
788 {
789     uint32_t tcnto;
790     uint32_t icnto;
791     uint64_t remain;
792     uint64_t counted;
793     uint64_t count;
794     uint64_t cur_progress;
795 
796     count = ptimer_get_count(s->ptimer_tick);
797     if (count) {
798         /* timer is still counting, called not from event */
799         counted = s->count - ptimer_get_count(s->ptimer_tick);
800         cur_progress = s->progress + counted;
801     } else {
802         /* timer expired earlier */
803         cur_progress = s->progress;
804     }
805 
806     remain = s->distance - cur_progress;
807 
808     if (!s->cnt_run) {
809         /* Both are stopped. */
810         tcnto = s->last_tcnto;
811     } else if (!s->int_run) {
812         /* INT counter is stopped, progress is by CNT timer */
813         tcnto = remain % s->tcntb;
814     } else {
815         /* Both are counting */
816         icnto = remain / s->tcntb;
817         if (icnto) {
818             tcnto = remain % (icnto * s->tcntb);
819         } else {
820             tcnto = remain % s->tcntb;
821         }
822     }
823 
824     return tcnto;
825 }
826 
827 /*
828  * Set new values of counters for CNT and INT timers
829  * Must be called within exynos4210_ltick_tx_begin/commit block.
830  */
831 static void exynos4210_ltick_set_cntb(struct tick_timer *s, uint32_t new_cnt,
832         uint32_t new_int)
833 {
834     uint32_t cnt_stopped = 0;
835     uint32_t int_stopped = 0;
836 
837     if (s->cnt_run) {
838         exynos4210_ltick_cnt_stop(s);
839         cnt_stopped = 1;
840     }
841 
842     if (s->int_run) {
843         exynos4210_ltick_int_stop(s);
844         int_stopped = 1;
845     }
846 
847     s->tcntb = new_cnt + 1;
848     s->icntb = new_int + 1;
849 
850     if (cnt_stopped) {
851         exynos4210_ltick_cnt_start(s);
852     }
853     if (int_stopped) {
854         exynos4210_ltick_int_start(s);
855     }
856 
857 }
858 
859 /*
860  * Calculate new counter value for tick timer
861  */
862 static void exynos4210_ltick_recalc_count(struct tick_timer *s)
863 {
864     uint64_t to_count;
865 
866     if ((s->cnt_run && s->last_tcnto) || (s->int_run && s->last_icnto)) {
867         /*
868          * one or both timers run and not counted to the end;
869          * distance is not passed, recalculate with last_tcnto * last_icnto
870          */
871 
872         if (s->last_tcnto) {
873             to_count = (uint64_t)s->last_tcnto * s->last_icnto;
874         } else {
875             to_count = s->last_icnto;
876         }
877     } else {
878         /* distance is passed, recalculate with tcnto * icnto */
879         if (s->icntb) {
880             s->distance = (uint64_t)s->tcntb * s->icntb;
881         } else {
882             s->distance = s->tcntb;
883         }
884 
885         to_count = s->distance;
886         s->progress = 0;
887     }
888 
889     if (to_count > MCT_LT_COUNTER_STEP) {
890         /* count by step */
891         s->count = MCT_LT_COUNTER_STEP;
892     } else {
893         s->count = to_count;
894     }
895 }
896 
897 /*
898  * Initialize tick_timer
899  */
900 static void exynos4210_ltick_timer_init(struct tick_timer *s)
901 {
902     exynos4210_ltick_int_stop(s);
903     exynos4210_ltick_tx_begin(s);
904     exynos4210_ltick_cnt_stop(s);
905     exynos4210_ltick_tx_commit(s);
906 
907     s->count = 0;
908     s->distance = 0;
909     s->progress = 0;
910     s->icntb = 0;
911     s->tcntb = 0;
912 }
913 
914 /*
915  * tick_timer event.
916  * Raises when abstract tick_timer expires.
917  */
918 static void exynos4210_ltick_timer_event(struct tick_timer *s)
919 {
920     s->progress += s->count;
921 }
922 
923 /*
924  * Local timer tick counter handler.
925  * Don't use reloaded timers. If timer counter = zero
926  * then handler called but after handler finished no
927  * timer reload occurs.
928  */
929 static void exynos4210_ltick_event(void *opaque)
930 {
931     Exynos4210MCTLT * s = (Exynos4210MCTLT *)opaque;
932     uint32_t tcnto;
933     uint32_t icnto;
934 #ifdef DEBUG_MCT
935     static uint64_t time1[2] = {0};
936     static uint64_t time2[2] = {0};
937 #endif
938 
939     /* Call tick_timer event handler, it will update its tcntb and icntb. */
940     exynos4210_ltick_timer_event(&s->tick_timer);
941 
942     /* get tick_timer cnt */
943     tcnto = exynos4210_ltick_cnt_get_cnto(&s->tick_timer);
944 
945     /* get tick_timer int */
946     icnto = exynos4210_ltick_int_get_cnto(&s->tick_timer);
947 
948     /* raise IRQ if needed */
949     if (!icnto && s->reg.tcon & L_TCON_INT_START) {
950         /* INT counter enabled and expired */
951 
952         s->reg.int_cstat |= L_INT_CSTAT_INTCNT;
953 
954         /* raise interrupt if enabled */
955         if (s->reg.int_enb & L_INT_INTENB_ICNTEIE) {
956 #ifdef DEBUG_MCT
957             time2[s->id] = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
958             DPRINTF("local timer[%d] IRQ: %llx\n", s->id,
959                     time2[s->id] - time1[s->id]);
960             time1[s->id] = time2[s->id];
961 #endif
962             qemu_irq_raise(s->irq);
963         }
964 
965         /* reload ICNTB */
966         if (s->reg.tcon & L_TCON_INTERVAL_MODE) {
967             exynos4210_ltick_set_cntb(&s->tick_timer,
968                     s->reg.cnt[L_REG_CNT_TCNTB],
969                     s->reg.cnt[L_REG_CNT_ICNTB]);
970         }
971     } else {
972         /* reload TCNTB */
973         if (!tcnto) {
974             exynos4210_ltick_set_cntb(&s->tick_timer,
975                     s->reg.cnt[L_REG_CNT_TCNTB],
976                     icnto);
977         }
978     }
979 
980     /* start tick_timer cnt */
981     exynos4210_ltick_cnt_start(&s->tick_timer);
982 
983     /* start tick_timer int */
984     exynos4210_ltick_int_start(&s->tick_timer);
985 }
986 
987 static void tx_ptimer_set_freq(ptimer_state *s, uint32_t freq)
988 {
989     /*
990      * callers of exynos4210_mct_update_freq() never do anything
991      * else that needs to be in the same ptimer transaction, so
992      * to avoid a lot of repetition we have a convenience function
993      * for begin/set_freq/commit.
994      */
995     ptimer_transaction_begin(s);
996     ptimer_set_freq(s, freq);
997     ptimer_transaction_commit(s);
998 }
999 
1000 /* update timer frequency */
1001 static void exynos4210_mct_update_freq(Exynos4210MCTState *s)
1002 {
1003     uint32_t freq = s->freq;
1004     s->freq = 24000000 /
1005             ((MCT_CFG_GET_PRESCALER(s->reg_mct_cfg) + 1) *
1006                     MCT_CFG_GET_DIVIDER(s->reg_mct_cfg));
1007 
1008     if (freq != s->freq) {
1009         DPRINTF("freq=%uHz\n", s->freq);
1010 
1011         /* global timer */
1012         tx_ptimer_set_freq(s->g_timer.ptimer_frc, s->freq);
1013 
1014         /* local timer */
1015         tx_ptimer_set_freq(s->l_timer[0].tick_timer.ptimer_tick, s->freq);
1016         tx_ptimer_set_freq(s->l_timer[0].ptimer_frc, s->freq);
1017         tx_ptimer_set_freq(s->l_timer[1].tick_timer.ptimer_tick, s->freq);
1018         tx_ptimer_set_freq(s->l_timer[1].ptimer_frc, s->freq);
1019     }
1020 }
1021 
1022 /* set defaul_timer values for all fields */
1023 static void exynos4210_mct_reset(DeviceState *d)
1024 {
1025     Exynos4210MCTState *s = EXYNOS4210_MCT(d);
1026     uint32_t i;
1027 
1028     s->reg_mct_cfg = 0;
1029 
1030     /* global timer */
1031     memset(&s->g_timer.reg, 0, sizeof(s->g_timer.reg));
1032     exynos4210_gfrc_tx_begin(&s->g_timer);
1033     exynos4210_gfrc_stop(&s->g_timer);
1034     exynos4210_gfrc_tx_commit(&s->g_timer);
1035 
1036     /* local timer */
1037     memset(s->l_timer[0].reg.cnt, 0, sizeof(s->l_timer[0].reg.cnt));
1038     memset(s->l_timer[1].reg.cnt, 0, sizeof(s->l_timer[1].reg.cnt));
1039     for (i = 0; i < 2; i++) {
1040         s->l_timer[i].reg.int_cstat = 0;
1041         s->l_timer[i].reg.int_enb = 0;
1042         s->l_timer[i].reg.tcon = 0;
1043         s->l_timer[i].reg.wstat = 0;
1044         s->l_timer[i].tick_timer.count = 0;
1045         s->l_timer[i].tick_timer.distance = 0;
1046         s->l_timer[i].tick_timer.progress = 0;
1047         exynos4210_lfrc_tx_begin(&s->l_timer[i]);
1048         ptimer_stop(s->l_timer[i].ptimer_frc);
1049         exynos4210_lfrc_tx_commit(&s->l_timer[i]);
1050 
1051         exynos4210_ltick_timer_init(&s->l_timer[i].tick_timer);
1052     }
1053 
1054     exynos4210_mct_update_freq(s);
1055 
1056 }
1057 
1058 /* Multi Core Timer read */
1059 static uint64_t exynos4210_mct_read(void *opaque, hwaddr offset,
1060         unsigned size)
1061 {
1062     Exynos4210MCTState *s = (Exynos4210MCTState *)opaque;
1063     int index;
1064     int shift;
1065     uint64_t count;
1066     uint32_t value = 0;
1067     int lt_i;
1068 
1069     switch (offset) {
1070 
1071     case MCT_CFG:
1072         value = s->reg_mct_cfg;
1073         break;
1074 
1075     case G_CNT_L: case G_CNT_U:
1076         shift = 8 * (offset & 0x4);
1077         count = exynos4210_gfrc_get_count(&s->g_timer);
1078         value = UINT32_MAX & (count >> shift);
1079         DPRINTF("read FRC=0x%llx\n", count);
1080         break;
1081 
1082     case G_CNT_WSTAT:
1083         value = s->g_timer.reg.cnt_wstat;
1084         break;
1085 
1086     case G_COMP_L(0): case G_COMP_L(1): case G_COMP_L(2): case G_COMP_L(3):
1087     case G_COMP_U(0): case G_COMP_U(1): case G_COMP_U(2): case G_COMP_U(3):
1088         index = GET_G_COMP_IDX(offset);
1089         shift = 8 * (offset & 0x4);
1090         value = UINT32_MAX & (s->g_timer.reg.comp[index] >> shift);
1091     break;
1092 
1093     case G_TCON:
1094         value = s->g_timer.reg.tcon;
1095         break;
1096 
1097     case G_INT_CSTAT:
1098         value = s->g_timer.reg.int_cstat;
1099         break;
1100 
1101     case G_INT_ENB:
1102         value = s->g_timer.reg.int_enb;
1103         break;
1104     case G_WSTAT:
1105         value = s->g_timer.reg.wstat;
1106         break;
1107 
1108     case G_COMP0_ADD_INCR: case G_COMP1_ADD_INCR:
1109     case G_COMP2_ADD_INCR: case G_COMP3_ADD_INCR:
1110         value = s->g_timer.reg.comp_add_incr[GET_G_COMP_ADD_INCR_IDX(offset)];
1111         break;
1112 
1113         /* Local timers */
1114     case L0_TCNTB: case L0_ICNTB: case L0_FRCNTB:
1115     case L1_TCNTB: case L1_ICNTB: case L1_FRCNTB:
1116         lt_i = GET_L_TIMER_IDX(offset);
1117         index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i);
1118         value = s->l_timer[lt_i].reg.cnt[index];
1119         break;
1120 
1121     case L0_TCNTO: case L1_TCNTO:
1122         lt_i = GET_L_TIMER_IDX(offset);
1123 
1124         value = exynos4210_ltick_cnt_get_cnto(&s->l_timer[lt_i].tick_timer);
1125         DPRINTF("local timer[%d] read TCNTO %x\n", lt_i, value);
1126         break;
1127 
1128     case L0_ICNTO: case L1_ICNTO:
1129         lt_i = GET_L_TIMER_IDX(offset);
1130 
1131         value = exynos4210_ltick_int_get_cnto(&s->l_timer[lt_i].tick_timer);
1132         DPRINTF("local timer[%d] read ICNTO %x\n", lt_i, value);
1133         break;
1134 
1135     case L0_FRCNTO: case L1_FRCNTO:
1136         lt_i = GET_L_TIMER_IDX(offset);
1137 
1138         value = exynos4210_lfrc_get_count(&s->l_timer[lt_i]);
1139         break;
1140 
1141     case L0_TCON: case L1_TCON:
1142         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1143         value = s->l_timer[lt_i].reg.tcon;
1144         break;
1145 
1146     case L0_INT_CSTAT: case L1_INT_CSTAT:
1147         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1148         value = s->l_timer[lt_i].reg.int_cstat;
1149         break;
1150 
1151     case L0_INT_ENB: case L1_INT_ENB:
1152         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1153         value = s->l_timer[lt_i].reg.int_enb;
1154         break;
1155 
1156     case L0_WSTAT: case L1_WSTAT:
1157         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1158         value = s->l_timer[lt_i].reg.wstat;
1159         break;
1160 
1161     default:
1162         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIX "\n",
1163                       __func__, offset);
1164         break;
1165     }
1166     return value;
1167 }
1168 
1169 /* MCT write */
1170 static void exynos4210_mct_write(void *opaque, hwaddr offset,
1171         uint64_t value, unsigned size)
1172 {
1173     Exynos4210MCTState *s = (Exynos4210MCTState *)opaque;
1174     int index;  /* index in buffer which represents register set */
1175     int shift;
1176     int lt_i;
1177     uint64_t new_frc;
1178     uint32_t i;
1179     uint32_t old_val;
1180 #ifdef DEBUG_MCT
1181     static uint32_t icntb_max[2] = {0};
1182     static uint32_t icntb_min[2] = {UINT32_MAX, UINT32_MAX};
1183     static uint32_t tcntb_max[2] = {0};
1184     static uint32_t tcntb_min[2] = {UINT32_MAX, UINT32_MAX};
1185 #endif
1186 
1187     new_frc = s->g_timer.reg.cnt;
1188 
1189     switch (offset) {
1190 
1191     case MCT_CFG:
1192         s->reg_mct_cfg = value;
1193         exynos4210_mct_update_freq(s);
1194         break;
1195 
1196     case G_CNT_L:
1197     case G_CNT_U:
1198         if (offset == G_CNT_L) {
1199 
1200             DPRINTF("global timer write to reg.cntl %llx\n", value);
1201 
1202             new_frc = (s->g_timer.reg.cnt & (uint64_t)UINT32_MAX << 32) + value;
1203             s->g_timer.reg.cnt_wstat |= G_CNT_WSTAT_L;
1204         }
1205         if (offset == G_CNT_U) {
1206 
1207             DPRINTF("global timer write to reg.cntu %llx\n", value);
1208 
1209             new_frc = (s->g_timer.reg.cnt & UINT32_MAX) +
1210                     ((uint64_t)value << 32);
1211             s->g_timer.reg.cnt_wstat |= G_CNT_WSTAT_U;
1212         }
1213 
1214         s->g_timer.reg.cnt = new_frc;
1215         exynos4210_gfrc_tx_begin(&s->g_timer);
1216         exynos4210_gfrc_restart(s);
1217         exynos4210_gfrc_tx_commit(&s->g_timer);
1218         break;
1219 
1220     case G_CNT_WSTAT:
1221         s->g_timer.reg.cnt_wstat &= ~(value);
1222         break;
1223 
1224     case G_COMP_L(0): case G_COMP_L(1): case G_COMP_L(2): case G_COMP_L(3):
1225     case G_COMP_U(0): case G_COMP_U(1): case G_COMP_U(2): case G_COMP_U(3):
1226         index = GET_G_COMP_IDX(offset);
1227         shift = 8 * (offset & 0x4);
1228         s->g_timer.reg.comp[index] =
1229                 (s->g_timer.reg.comp[index] &
1230                 (((uint64_t)UINT32_MAX << 32) >> shift)) +
1231                 (value << shift);
1232 
1233         DPRINTF("comparator %d write 0x%llx val << %d\n", index, value, shift);
1234 
1235         if (offset & 0x4) {
1236             s->g_timer.reg.wstat |= G_WSTAT_COMP_U(index);
1237         } else {
1238             s->g_timer.reg.wstat |= G_WSTAT_COMP_L(index);
1239         }
1240 
1241         exynos4210_gfrc_tx_begin(&s->g_timer);
1242         exynos4210_gfrc_restart(s);
1243         exynos4210_gfrc_tx_commit(&s->g_timer);
1244         break;
1245 
1246     case G_TCON:
1247         old_val = s->g_timer.reg.tcon;
1248         s->g_timer.reg.tcon = value;
1249         s->g_timer.reg.wstat |= G_WSTAT_TCON_WRITE;
1250 
1251         DPRINTF("global timer write to reg.g_tcon %llx\n", value);
1252 
1253         exynos4210_gfrc_tx_begin(&s->g_timer);
1254 
1255         /* Start FRC if transition from disabled to enabled */
1256         if ((value & G_TCON_TIMER_ENABLE) > (old_val &
1257                 G_TCON_TIMER_ENABLE)) {
1258             exynos4210_gfrc_restart(s);
1259         }
1260         if ((value & G_TCON_TIMER_ENABLE) < (old_val &
1261                 G_TCON_TIMER_ENABLE)) {
1262             exynos4210_gfrc_stop(&s->g_timer);
1263         }
1264 
1265         /* Start CMP if transition from disabled to enabled */
1266         for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1267             if ((value & G_TCON_COMP_ENABLE(i)) != (old_val &
1268                     G_TCON_COMP_ENABLE(i))) {
1269                 exynos4210_gfrc_restart(s);
1270             }
1271         }
1272 
1273         exynos4210_gfrc_tx_commit(&s->g_timer);
1274         break;
1275 
1276     case G_INT_CSTAT:
1277         s->g_timer.reg.int_cstat &= ~(value);
1278         for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1279             if (value & G_INT_CSTAT_COMP(i)) {
1280                 exynos4210_gcomp_lower_irq(&s->g_timer, i);
1281             }
1282         }
1283         break;
1284 
1285     case G_INT_ENB:
1286         /* Raise IRQ if transition from disabled to enabled and CSTAT pending */
1287         for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1288             if ((value & G_INT_ENABLE(i)) > (s->g_timer.reg.tcon &
1289                     G_INT_ENABLE(i))) {
1290                 if (s->g_timer.reg.int_cstat & G_INT_CSTAT_COMP(i)) {
1291                     exynos4210_gcomp_raise_irq(&s->g_timer, i);
1292                 }
1293             }
1294 
1295             if ((value & G_INT_ENABLE(i)) < (s->g_timer.reg.tcon &
1296                     G_INT_ENABLE(i))) {
1297                 exynos4210_gcomp_lower_irq(&s->g_timer, i);
1298             }
1299         }
1300 
1301         DPRINTF("global timer INT enable %llx\n", value);
1302         s->g_timer.reg.int_enb = value;
1303         break;
1304 
1305     case G_WSTAT:
1306         s->g_timer.reg.wstat &= ~(value);
1307         break;
1308 
1309     case G_COMP0_ADD_INCR: case G_COMP1_ADD_INCR:
1310     case G_COMP2_ADD_INCR: case G_COMP3_ADD_INCR:
1311         index = GET_G_COMP_ADD_INCR_IDX(offset);
1312         s->g_timer.reg.comp_add_incr[index] = value;
1313         s->g_timer.reg.wstat |= G_WSTAT_COMP_ADDINCR(index);
1314         break;
1315 
1316         /* Local timers */
1317     case L0_TCON: case L1_TCON:
1318         lt_i = GET_L_TIMER_IDX(offset);
1319         old_val = s->l_timer[lt_i].reg.tcon;
1320 
1321         s->l_timer[lt_i].reg.wstat |= L_WSTAT_TCON_WRITE;
1322         s->l_timer[lt_i].reg.tcon = value;
1323 
1324         exynos4210_ltick_tx_begin(&s->l_timer[lt_i].tick_timer);
1325         /* Stop local CNT */
1326         if ((value & L_TCON_TICK_START) <
1327                 (old_val & L_TCON_TICK_START)) {
1328             DPRINTF("local timer[%d] stop cnt\n", lt_i);
1329             exynos4210_ltick_cnt_stop(&s->l_timer[lt_i].tick_timer);
1330         }
1331 
1332         /* Stop local INT */
1333         if ((value & L_TCON_INT_START) <
1334                 (old_val & L_TCON_INT_START)) {
1335             DPRINTF("local timer[%d] stop int\n", lt_i);
1336             exynos4210_ltick_int_stop(&s->l_timer[lt_i].tick_timer);
1337         }
1338 
1339         /* Start local CNT */
1340         if ((value & L_TCON_TICK_START) >
1341         (old_val & L_TCON_TICK_START)) {
1342             DPRINTF("local timer[%d] start cnt\n", lt_i);
1343             exynos4210_ltick_cnt_start(&s->l_timer[lt_i].tick_timer);
1344         }
1345 
1346         /* Start local INT */
1347         if ((value & L_TCON_INT_START) >
1348         (old_val & L_TCON_INT_START)) {
1349             DPRINTF("local timer[%d] start int\n", lt_i);
1350             exynos4210_ltick_int_start(&s->l_timer[lt_i].tick_timer);
1351         }
1352         exynos4210_ltick_tx_commit(&s->l_timer[lt_i].tick_timer);
1353 
1354         /* Start or Stop local FRC if TCON changed */
1355         exynos4210_lfrc_tx_begin(&s->l_timer[lt_i]);
1356         if ((value & L_TCON_FRC_START) >
1357         (s->l_timer[lt_i].reg.tcon & L_TCON_FRC_START)) {
1358             DPRINTF("local timer[%d] start frc\n", lt_i);
1359             exynos4210_lfrc_start(&s->l_timer[lt_i]);
1360         }
1361         if ((value & L_TCON_FRC_START) <
1362                 (s->l_timer[lt_i].reg.tcon & L_TCON_FRC_START)) {
1363             DPRINTF("local timer[%d] stop frc\n", lt_i);
1364             exynos4210_lfrc_stop(&s->l_timer[lt_i]);
1365         }
1366         exynos4210_lfrc_tx_commit(&s->l_timer[lt_i]);
1367         break;
1368 
1369     case L0_TCNTB: case L1_TCNTB:
1370         lt_i = GET_L_TIMER_IDX(offset);
1371 
1372         /*
1373          * TCNTB is updated to internal register only after CNT expired.
1374          * Due to this we should reload timer to nearest moment when CNT is
1375          * expired and then in event handler update tcntb to new TCNTB value.
1376          */
1377         exynos4210_ltick_tx_begin(&s->l_timer[lt_i].tick_timer);
1378         exynos4210_ltick_set_cntb(&s->l_timer[lt_i].tick_timer, value,
1379                 s->l_timer[lt_i].tick_timer.icntb);
1380         exynos4210_ltick_tx_commit(&s->l_timer[lt_i].tick_timer);
1381 
1382         s->l_timer[lt_i].reg.wstat |= L_WSTAT_TCNTB_WRITE;
1383         s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB] = value;
1384 
1385 #ifdef DEBUG_MCT
1386         if (tcntb_min[lt_i] > value) {
1387             tcntb_min[lt_i] = value;
1388         }
1389         if (tcntb_max[lt_i] < value) {
1390             tcntb_max[lt_i] = value;
1391         }
1392         DPRINTF("local timer[%d] TCNTB write %llx; max=%x, min=%x\n",
1393                 lt_i, value, tcntb_max[lt_i], tcntb_min[lt_i]);
1394 #endif
1395         break;
1396 
1397     case L0_ICNTB: case L1_ICNTB:
1398         lt_i = GET_L_TIMER_IDX(offset);
1399 
1400         s->l_timer[lt_i].reg.wstat |= L_WSTAT_ICNTB_WRITE;
1401         s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] = value &
1402                 ~L_ICNTB_MANUAL_UPDATE;
1403 
1404         /*
1405          * We need to avoid too small values for TCNTB*ICNTB. If not, IRQ event
1406          * could raise too fast disallowing QEMU to execute target code.
1407          */
1408         if (s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] *
1409             s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB] < MCT_LT_CNT_LOW_LIMIT) {
1410             if (!s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB]) {
1411                 s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] =
1412                         MCT_LT_CNT_LOW_LIMIT;
1413             } else {
1414                 s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] =
1415                         MCT_LT_CNT_LOW_LIMIT /
1416                         s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB];
1417             }
1418         }
1419 
1420         if (value & L_ICNTB_MANUAL_UPDATE) {
1421             exynos4210_ltick_set_cntb(&s->l_timer[lt_i].tick_timer,
1422                     s->l_timer[lt_i].tick_timer.tcntb,
1423                     s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB]);
1424         }
1425 
1426 #ifdef DEBUG_MCT
1427         if (icntb_min[lt_i] > value) {
1428             icntb_min[lt_i] = value;
1429         }
1430         if (icntb_max[lt_i] < value) {
1431             icntb_max[lt_i] = value;
1432         }
1433         DPRINTF("local timer[%d] ICNTB write %llx; max=%x, min=%x\n\n",
1434                 lt_i, value, icntb_max[lt_i], icntb_min[lt_i]);
1435 #endif
1436         break;
1437 
1438     case L0_FRCNTB: case L1_FRCNTB:
1439         lt_i = GET_L_TIMER_IDX(offset);
1440         DPRINTF("local timer[%d] FRCNTB write %llx\n", lt_i, value);
1441 
1442         s->l_timer[lt_i].reg.wstat |= L_WSTAT_FRCCNTB_WRITE;
1443         s->l_timer[lt_i].reg.cnt[L_REG_CNT_FRCCNTB] = value;
1444 
1445         break;
1446 
1447     case L0_TCNTO: case L1_TCNTO:
1448     case L0_ICNTO: case L1_ICNTO:
1449     case L0_FRCNTO: case L1_FRCNTO:
1450         qemu_log_mask(LOG_GUEST_ERROR,
1451                       "exynos4210.mct: write to RO register " HWADDR_FMT_plx,
1452                       offset);
1453         break;
1454 
1455     case L0_INT_CSTAT: case L1_INT_CSTAT:
1456         lt_i = GET_L_TIMER_IDX(offset);
1457 
1458         DPRINTF("local timer[%d] CSTAT write %llx\n", lt_i, value);
1459 
1460         s->l_timer[lt_i].reg.int_cstat &= ~value;
1461         if (!s->l_timer[lt_i].reg.int_cstat) {
1462             qemu_irq_lower(s->l_timer[lt_i].irq);
1463         }
1464         break;
1465 
1466     case L0_INT_ENB: case L1_INT_ENB:
1467         lt_i = GET_L_TIMER_IDX(offset);
1468         old_val = s->l_timer[lt_i].reg.int_enb;
1469 
1470         /* Raise Local timer IRQ if cstat is pending */
1471         if ((value & L_INT_INTENB_ICNTEIE) > (old_val & L_INT_INTENB_ICNTEIE)) {
1472             if (s->l_timer[lt_i].reg.int_cstat & L_INT_CSTAT_INTCNT) {
1473                 qemu_irq_raise(s->l_timer[lt_i].irq);
1474             }
1475         }
1476 
1477         s->l_timer[lt_i].reg.int_enb = value;
1478 
1479         break;
1480 
1481     case L0_WSTAT: case L1_WSTAT:
1482         lt_i = GET_L_TIMER_IDX(offset);
1483 
1484         s->l_timer[lt_i].reg.wstat &= ~value;
1485         break;
1486 
1487     default:
1488         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIX "\n",
1489                       __func__, offset);
1490         break;
1491     }
1492 }
1493 
1494 static const MemoryRegionOps exynos4210_mct_ops = {
1495     .read = exynos4210_mct_read,
1496     .write = exynos4210_mct_write,
1497     .endianness = DEVICE_NATIVE_ENDIAN,
1498 };
1499 
1500 /* MCT init */
1501 static void exynos4210_mct_init(Object *obj)
1502 {
1503     int i;
1504     Exynos4210MCTState *s = EXYNOS4210_MCT(obj);
1505     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
1506 
1507     /* Global timer */
1508     s->g_timer.ptimer_frc = ptimer_init(exynos4210_gfrc_event, s,
1509                                         PTIMER_POLICY_LEGACY);
1510     memset(&s->g_timer.reg, 0, sizeof(struct gregs));
1511 
1512     /* Local timers */
1513     for (i = 0; i < 2; i++) {
1514         s->l_timer[i].tick_timer.ptimer_tick =
1515             ptimer_init(exynos4210_ltick_event, &s->l_timer[i],
1516                         PTIMER_POLICY_LEGACY);
1517         s->l_timer[i].ptimer_frc =
1518             ptimer_init(exynos4210_lfrc_event, &s->l_timer[i],
1519                         PTIMER_POLICY_LEGACY);
1520         s->l_timer[i].id = i;
1521     }
1522 
1523     /* IRQs */
1524     for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1525         sysbus_init_irq(dev, &s->g_timer.irq[i]);
1526     }
1527     for (i = 0; i < 2; i++) {
1528         sysbus_init_irq(dev, &s->l_timer[i].irq);
1529     }
1530 
1531     memory_region_init_io(&s->iomem, obj, &exynos4210_mct_ops, s,
1532                           "exynos4210-mct", MCT_SFR_SIZE);
1533     sysbus_init_mmio(dev, &s->iomem);
1534 }
1535 
1536 static void exynos4210_mct_finalize(Object *obj)
1537 {
1538     int i;
1539     Exynos4210MCTState *s = EXYNOS4210_MCT(obj);
1540 
1541     ptimer_free(s->g_timer.ptimer_frc);
1542 
1543     for (i = 0; i < 2; i++) {
1544         ptimer_free(s->l_timer[i].tick_timer.ptimer_tick);
1545         ptimer_free(s->l_timer[i].ptimer_frc);
1546     }
1547 }
1548 
1549 static void exynos4210_mct_class_init(ObjectClass *klass, void *data)
1550 {
1551     DeviceClass *dc = DEVICE_CLASS(klass);
1552 
1553     dc->reset = exynos4210_mct_reset;
1554     dc->vmsd = &vmstate_exynos4210_mct_state;
1555 }
1556 
1557 static const TypeInfo exynos4210_mct_info = {
1558     .name          = TYPE_EXYNOS4210_MCT,
1559     .parent        = TYPE_SYS_BUS_DEVICE,
1560     .instance_size = sizeof(Exynos4210MCTState),
1561     .instance_init = exynos4210_mct_init,
1562     .instance_finalize = exynos4210_mct_finalize,
1563     .class_init    = exynos4210_mct_class_init,
1564 };
1565 
1566 static void exynos4210_mct_register_types(void)
1567 {
1568     type_register_static(&exynos4210_mct_info);
1569 }
1570 
1571 type_init(exynos4210_mct_register_types)
1572