xref: /openbmc/qemu/hw/timer/exynos4210_mct.c (revision 9ede4ec094340cd788e9260f72e64988c5738530)
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/hw.h"
58 #include "hw/sysbus.h"
59 #include "migration/vmstate.h"
60 #include "qemu/timer.h"
61 #include "qemu/main-loop.h"
62 #include "qemu/module.h"
63 #include "hw/ptimer.h"
64 
65 #include "hw/arm/exynos4210.h"
66 #include "hw/hw.h"
67 #include "hw/irq.h"
68 
69 //#define DEBUG_MCT
70 
71 #ifdef DEBUG_MCT
72 #define DPRINTF(fmt, ...) \
73         do { fprintf(stdout, "MCT: [%24s:%5d] " fmt, __func__, __LINE__, \
74                      ## __VA_ARGS__); } while (0)
75 #else
76 #define DPRINTF(fmt, ...) do {} while (0)
77 #endif
78 
79 #define    MCT_CFG          0x000
80 #define    G_CNT_L          0x100
81 #define    G_CNT_U          0x104
82 #define    G_CNT_WSTAT      0x110
83 #define    G_COMP0_L        0x200
84 #define    G_COMP0_U        0x204
85 #define    G_COMP0_ADD_INCR 0x208
86 #define    G_COMP1_L        0x210
87 #define    G_COMP1_U        0x214
88 #define    G_COMP1_ADD_INCR 0x218
89 #define    G_COMP2_L        0x220
90 #define    G_COMP2_U        0x224
91 #define    G_COMP2_ADD_INCR 0x228
92 #define    G_COMP3_L        0x230
93 #define    G_COMP3_U        0x234
94 #define    G_COMP3_ADD_INCR 0x238
95 #define    G_TCON           0x240
96 #define    G_INT_CSTAT      0x244
97 #define    G_INT_ENB        0x248
98 #define    G_WSTAT          0x24C
99 #define    L0_TCNTB         0x300
100 #define    L0_TCNTO         0x304
101 #define    L0_ICNTB         0x308
102 #define    L0_ICNTO         0x30C
103 #define    L0_FRCNTB        0x310
104 #define    L0_FRCNTO        0x314
105 #define    L0_TCON          0x320
106 #define    L0_INT_CSTAT     0x330
107 #define    L0_INT_ENB       0x334
108 #define    L0_WSTAT         0x340
109 #define    L1_TCNTB         0x400
110 #define    L1_TCNTO         0x404
111 #define    L1_ICNTB         0x408
112 #define    L1_ICNTO         0x40C
113 #define    L1_FRCNTB        0x410
114 #define    L1_FRCNTO        0x414
115 #define    L1_TCON          0x420
116 #define    L1_INT_CSTAT     0x430
117 #define    L1_INT_ENB       0x434
118 #define    L1_WSTAT         0x440
119 
120 #define MCT_CFG_GET_PRESCALER(x)    ((x) & 0xFF)
121 #define MCT_CFG_GET_DIVIDER(x)      (1 << ((x) >> 8 & 7))
122 
123 #define GET_G_COMP_IDX(offset)          (((offset) - G_COMP0_L) / 0x10)
124 #define GET_G_COMP_ADD_INCR_IDX(offset) (((offset) - G_COMP0_ADD_INCR) / 0x10)
125 
126 #define G_COMP_L(x) (G_COMP0_L + (x) * 0x10)
127 #define G_COMP_U(x) (G_COMP0_U + (x) * 0x10)
128 
129 #define G_COMP_ADD_INCR(x)  (G_COMP0_ADD_INCR + (x) * 0x10)
130 
131 /* MCT bits */
132 #define G_TCON_COMP_ENABLE(x)   (1 << 2 * (x))
133 #define G_TCON_AUTO_ICREMENT(x) (1 << (2 * (x) + 1))
134 #define G_TCON_TIMER_ENABLE     (1 << 8)
135 
136 #define G_INT_ENABLE(x)         (1 << (x))
137 #define G_INT_CSTAT_COMP(x)     (1 << (x))
138 
139 #define G_CNT_WSTAT_L           1
140 #define G_CNT_WSTAT_U           2
141 
142 #define G_WSTAT_COMP_L(x)       (1 << 4 * (x))
143 #define G_WSTAT_COMP_U(x)       (1 << ((4 * (x)) + 1))
144 #define G_WSTAT_COMP_ADDINCR(x) (1 << ((4 * (x)) + 2))
145 #define G_WSTAT_TCON_WRITE      (1 << 16)
146 
147 #define GET_L_TIMER_IDX(offset) ((((offset) & 0xF00) - L0_TCNTB) / 0x100)
148 #define GET_L_TIMER_CNT_REG_IDX(offset, lt_i) \
149         (((offset) - (L0_TCNTB + 0x100 * (lt_i))) >> 2)
150 
151 #define L_ICNTB_MANUAL_UPDATE   (1 << 31)
152 
153 #define L_TCON_TICK_START       (1)
154 #define L_TCON_INT_START        (1 << 1)
155 #define L_TCON_INTERVAL_MODE    (1 << 2)
156 #define L_TCON_FRC_START        (1 << 3)
157 
158 #define L_INT_CSTAT_INTCNT      (1 << 0)
159 #define L_INT_CSTAT_FRCCNT      (1 << 1)
160 
161 #define L_INT_INTENB_ICNTEIE    (1 << 0)
162 #define L_INT_INTENB_FRCEIE     (1 << 1)
163 
164 #define L_WSTAT_TCNTB_WRITE     (1 << 0)
165 #define L_WSTAT_ICNTB_WRITE     (1 << 1)
166 #define L_WSTAT_FRCCNTB_WRITE   (1 << 2)
167 #define L_WSTAT_TCON_WRITE      (1 << 3)
168 
169 enum LocalTimerRegCntIndexes {
170     L_REG_CNT_TCNTB,
171     L_REG_CNT_TCNTO,
172     L_REG_CNT_ICNTB,
173     L_REG_CNT_ICNTO,
174     L_REG_CNT_FRCCNTB,
175     L_REG_CNT_FRCCNTO,
176 
177     L_REG_CNT_AMOUNT
178 };
179 
180 #define MCT_SFR_SIZE            0x444
181 
182 #define MCT_GT_CMP_NUM          4
183 
184 #define MCT_GT_COUNTER_STEP     0x100000000ULL
185 #define MCT_LT_COUNTER_STEP     0x100000000ULL
186 #define MCT_LT_CNT_LOW_LIMIT    0x100
187 
188 /* global timer */
189 typedef struct {
190     qemu_irq  irq[MCT_GT_CMP_NUM];
191 
192     struct gregs {
193         uint64_t cnt;
194         uint32_t cnt_wstat;
195         uint32_t tcon;
196         uint32_t int_cstat;
197         uint32_t int_enb;
198         uint32_t wstat;
199         uint64_t comp[MCT_GT_CMP_NUM];
200         uint32_t comp_add_incr[MCT_GT_CMP_NUM];
201     } reg;
202 
203     uint64_t count;            /* Value FRC was armed with */
204     int32_t curr_comp;             /* Current comparator FRC is running to */
205 
206     ptimer_state *ptimer_frc;                   /* FRC timer */
207 
208 } Exynos4210MCTGT;
209 
210 /* local timer */
211 typedef struct {
212     int         id;             /* timer id */
213     qemu_irq    irq;            /* local timer irq */
214 
215     struct tick_timer {
216         uint32_t cnt_run;           /* cnt timer is running */
217         uint32_t int_run;           /* int timer is running */
218 
219         uint32_t last_icnto;
220         uint32_t last_tcnto;
221         uint32_t tcntb;             /* initial value for TCNTB */
222         uint32_t icntb;             /* initial value for ICNTB */
223 
224         /* for step mode */
225         uint64_t    distance;       /* distance to count to the next event */
226         uint64_t    progress;       /* progress when counting by steps */
227         uint64_t    count;          /* count to arm timer with */
228 
229         ptimer_state *ptimer_tick;  /* timer for tick counter */
230     } tick_timer;
231 
232     /* use ptimer.c to represent count down timer */
233 
234     ptimer_state *ptimer_frc;   /* timer for free running counter */
235 
236     /* registers */
237     struct lregs {
238         uint32_t    cnt[L_REG_CNT_AMOUNT];
239         uint32_t    tcon;
240         uint32_t    int_cstat;
241         uint32_t    int_enb;
242         uint32_t    wstat;
243     } reg;
244 
245 } Exynos4210MCTLT;
246 
247 #define TYPE_EXYNOS4210_MCT "exynos4210.mct"
248 #define EXYNOS4210_MCT(obj) \
249     OBJECT_CHECK(Exynos4210MCTState, (obj), TYPE_EXYNOS4210_MCT)
250 
251 typedef struct Exynos4210MCTState {
252     SysBusDevice parent_obj;
253 
254     MemoryRegion iomem;
255 
256     /* Registers */
257     uint32_t    reg_mct_cfg;
258 
259     Exynos4210MCTLT l_timer[2];
260     Exynos4210MCTGT g_timer;
261 
262     uint32_t    freq;                   /* all timers tick frequency, TCLK */
263 } Exynos4210MCTState;
264 
265 /*** VMState ***/
266 static const VMStateDescription vmstate_tick_timer = {
267     .name = "exynos4210.mct.tick_timer",
268     .version_id = 1,
269     .minimum_version_id = 1,
270     .fields = (VMStateField[]) {
271         VMSTATE_UINT32(cnt_run, struct tick_timer),
272         VMSTATE_UINT32(int_run, struct tick_timer),
273         VMSTATE_UINT32(last_icnto, struct tick_timer),
274         VMSTATE_UINT32(last_tcnto, struct tick_timer),
275         VMSTATE_UINT32(tcntb, struct tick_timer),
276         VMSTATE_UINT32(icntb, struct tick_timer),
277         VMSTATE_UINT64(distance, struct tick_timer),
278         VMSTATE_UINT64(progress, struct tick_timer),
279         VMSTATE_UINT64(count, struct tick_timer),
280         VMSTATE_PTIMER(ptimer_tick, struct tick_timer),
281         VMSTATE_END_OF_LIST()
282     }
283 };
284 
285 static const VMStateDescription vmstate_lregs = {
286     .name = "exynos4210.mct.lregs",
287     .version_id = 1,
288     .minimum_version_id = 1,
289     .fields = (VMStateField[]) {
290         VMSTATE_UINT32_ARRAY(cnt, struct lregs, L_REG_CNT_AMOUNT),
291         VMSTATE_UINT32(tcon, struct lregs),
292         VMSTATE_UINT32(int_cstat, struct lregs),
293         VMSTATE_UINT32(int_enb, struct lregs),
294         VMSTATE_UINT32(wstat, struct lregs),
295         VMSTATE_END_OF_LIST()
296     }
297 };
298 
299 static const VMStateDescription vmstate_exynos4210_mct_lt = {
300     .name = "exynos4210.mct.lt",
301     .version_id = 1,
302     .minimum_version_id = 1,
303     .fields = (VMStateField[]) {
304         VMSTATE_INT32(id, Exynos4210MCTLT),
305         VMSTATE_STRUCT(tick_timer, Exynos4210MCTLT, 0,
306                 vmstate_tick_timer,
307                 struct tick_timer),
308         VMSTATE_PTIMER(ptimer_frc, Exynos4210MCTLT),
309         VMSTATE_STRUCT(reg, Exynos4210MCTLT, 0,
310                 vmstate_lregs,
311                 struct lregs),
312         VMSTATE_END_OF_LIST()
313     }
314 };
315 
316 static const VMStateDescription vmstate_gregs = {
317     .name = "exynos4210.mct.lregs",
318     .version_id = 1,
319     .minimum_version_id = 1,
320     .fields = (VMStateField[]) {
321         VMSTATE_UINT64(cnt, struct gregs),
322         VMSTATE_UINT32(cnt_wstat, struct gregs),
323         VMSTATE_UINT32(tcon, struct gregs),
324         VMSTATE_UINT32(int_cstat, struct gregs),
325         VMSTATE_UINT32(int_enb, struct gregs),
326         VMSTATE_UINT32(wstat, struct gregs),
327         VMSTATE_UINT64_ARRAY(comp, struct gregs, MCT_GT_CMP_NUM),
328         VMSTATE_UINT32_ARRAY(comp_add_incr, struct gregs,
329                 MCT_GT_CMP_NUM),
330         VMSTATE_END_OF_LIST()
331     }
332 };
333 
334 static const VMStateDescription vmstate_exynos4210_mct_gt = {
335     .name = "exynos4210.mct.lt",
336     .version_id = 1,
337     .minimum_version_id = 1,
338     .fields = (VMStateField[]) {
339         VMSTATE_STRUCT(reg, Exynos4210MCTGT, 0, vmstate_gregs,
340                 struct gregs),
341         VMSTATE_UINT64(count, Exynos4210MCTGT),
342         VMSTATE_INT32(curr_comp, Exynos4210MCTGT),
343         VMSTATE_PTIMER(ptimer_frc, Exynos4210MCTGT),
344         VMSTATE_END_OF_LIST()
345     }
346 };
347 
348 static const VMStateDescription vmstate_exynos4210_mct_state = {
349     .name = "exynos4210.mct",
350     .version_id = 1,
351     .minimum_version_id = 1,
352     .fields = (VMStateField[]) {
353         VMSTATE_UINT32(reg_mct_cfg, Exynos4210MCTState),
354         VMSTATE_STRUCT_ARRAY(l_timer, Exynos4210MCTState, 2, 0,
355             vmstate_exynos4210_mct_lt, Exynos4210MCTLT),
356         VMSTATE_STRUCT(g_timer, Exynos4210MCTState, 0,
357             vmstate_exynos4210_mct_gt, Exynos4210MCTGT),
358         VMSTATE_UINT32(freq, Exynos4210MCTState),
359         VMSTATE_END_OF_LIST()
360     }
361 };
362 
363 static void exynos4210_mct_update_freq(Exynos4210MCTState *s);
364 
365 /*
366  * Set counter of FRC global timer.
367  * Must be called within exynos4210_gfrc_tx_begin/commit block.
368  */
369 static void exynos4210_gfrc_set_count(Exynos4210MCTGT *s, uint64_t count)
370 {
371     s->count = count;
372     DPRINTF("global timer frc set count 0x%llx\n", count);
373     ptimer_set_count(s->ptimer_frc, count);
374 }
375 
376 /*
377  * Get counter of FRC global timer.
378  */
379 static uint64_t exynos4210_gfrc_get_count(Exynos4210MCTGT *s)
380 {
381     uint64_t count = 0;
382     count = ptimer_get_count(s->ptimer_frc);
383     count = s->count - count;
384     return s->reg.cnt + count;
385 }
386 
387 /*
388  * Stop global FRC timer
389  * Must be called within exynos4210_gfrc_tx_begin/commit block.
390  */
391 static void exynos4210_gfrc_stop(Exynos4210MCTGT *s)
392 {
393     DPRINTF("global timer frc stop\n");
394 
395     ptimer_stop(s->ptimer_frc);
396 }
397 
398 /*
399  * Start global FRC timer
400  * Must be called within exynos4210_gfrc_tx_begin/commit block.
401  */
402 static void exynos4210_gfrc_start(Exynos4210MCTGT *s)
403 {
404     DPRINTF("global timer frc start\n");
405 
406     ptimer_run(s->ptimer_frc, 1);
407 }
408 
409 /*
410  * Start ptimer transaction for global FRC timer; this is just for
411  * consistency with the way we wrap operations like stop and run.
412  */
413 static void exynos4210_gfrc_tx_begin(Exynos4210MCTGT *s)
414 {
415     ptimer_transaction_begin(s->ptimer_frc);
416 }
417 
418 /* Commit ptimer transaction for global FRC timer. */
419 static void exynos4210_gfrc_tx_commit(Exynos4210MCTGT *s)
420 {
421     ptimer_transaction_commit(s->ptimer_frc);
422 }
423 
424 /*
425  * Find next nearest Comparator. If current Comparator value equals to other
426  * Comparator value, skip them both
427  */
428 static int32_t exynos4210_gcomp_find(Exynos4210MCTState *s)
429 {
430     int res;
431     int i;
432     int enabled;
433     uint64_t min;
434     int min_comp_i;
435     uint64_t gfrc;
436     uint64_t distance;
437     uint64_t distance_min;
438     int comp_i;
439 
440     /* get gfrc count */
441     gfrc = exynos4210_gfrc_get_count(&s->g_timer);
442 
443     min = UINT64_MAX;
444     distance_min = UINT64_MAX;
445     comp_i = MCT_GT_CMP_NUM;
446     min_comp_i = MCT_GT_CMP_NUM;
447     enabled = 0;
448 
449     /* lookup for nearest comparator */
450     for (i = 0; i < MCT_GT_CMP_NUM; i++) {
451 
452         if (s->g_timer.reg.tcon & G_TCON_COMP_ENABLE(i)) {
453 
454             enabled = 1;
455 
456             if (s->g_timer.reg.comp[i] > gfrc) {
457                 /* Comparator is upper then FRC */
458                 distance = s->g_timer.reg.comp[i] - gfrc;
459 
460                 if (distance <= distance_min) {
461                     distance_min = distance;
462                     comp_i = i;
463                 }
464             } else {
465                 /* Comparator is below FRC, find the smallest */
466 
467                 if (s->g_timer.reg.comp[i] <= min) {
468                     min = s->g_timer.reg.comp[i];
469                     min_comp_i = i;
470                 }
471             }
472         }
473     }
474 
475     if (!enabled) {
476         /* All Comparators disabled */
477         res = -1;
478     } else if (comp_i < MCT_GT_CMP_NUM) {
479         /* Found upper Comparator */
480         res = comp_i;
481     } else {
482         /* All Comparators are below or equal to FRC  */
483         res = min_comp_i;
484     }
485 
486     DPRINTF("found comparator %d: comp 0x%llx distance 0x%llx, gfrc 0x%llx\n",
487             res,
488             s->g_timer.reg.comp[res],
489             distance_min,
490             gfrc);
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[%d] 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  */
612 static void exynos4210_lfrc_update_count(Exynos4210MCTLT *s)
613 {
614     if (!s->reg.cnt[L_REG_CNT_FRCCNTB]) {
615         ptimer_set_count(s->ptimer_frc, MCT_LT_COUNTER_STEP);
616     } else {
617         ptimer_set_count(s->ptimer_frc, s->reg.cnt[L_REG_CNT_FRCCNTB]);
618     }
619 }
620 
621 /*
622  * Start local FRC timer
623  */
624 static void exynos4210_lfrc_start(Exynos4210MCTLT *s)
625 {
626     ptimer_run(s->ptimer_frc, 1);
627 }
628 
629 /*
630  * Stop local FRC timer
631  */
632 static void exynos4210_lfrc_stop(Exynos4210MCTLT *s)
633 {
634     ptimer_stop(s->ptimer_frc);
635 }
636 
637 /*
638  * Local timer free running counter tick handler
639  */
640 static void exynos4210_lfrc_event(void *opaque)
641 {
642     Exynos4210MCTLT * s = (Exynos4210MCTLT *)opaque;
643 
644     /* local frc expired */
645 
646     DPRINTF("\n");
647 
648     s->reg.int_cstat |= L_INT_CSTAT_FRCCNT;
649 
650     /* update frc counter */
651     exynos4210_lfrc_update_count(s);
652 
653     /* raise irq */
654     if (s->reg.int_enb & L_INT_INTENB_FRCEIE) {
655         qemu_irq_raise(s->irq);
656     }
657 
658     /*  we reached here, this means that timer is enabled */
659     exynos4210_lfrc_start(s);
660 }
661 
662 static uint32_t exynos4210_ltick_int_get_cnto(struct tick_timer *s);
663 static uint32_t exynos4210_ltick_cnt_get_cnto(struct tick_timer *s);
664 static void exynos4210_ltick_recalc_count(struct tick_timer *s);
665 
666 /*
667  * Action on enabling local tick int timer
668  */
669 static void exynos4210_ltick_int_start(struct tick_timer *s)
670 {
671     if (!s->int_run) {
672         s->int_run = 1;
673     }
674 }
675 
676 /*
677  * Action on disabling local tick int timer
678  */
679 static void exynos4210_ltick_int_stop(struct tick_timer *s)
680 {
681     if (s->int_run) {
682         s->last_icnto = exynos4210_ltick_int_get_cnto(s);
683         s->int_run = 0;
684     }
685 }
686 
687 /*
688  * Get count for INT timer
689  */
690 static uint32_t exynos4210_ltick_int_get_cnto(struct tick_timer *s)
691 {
692     uint32_t icnto;
693     uint64_t remain;
694     uint64_t count;
695     uint64_t counted;
696     uint64_t cur_progress;
697 
698     count = ptimer_get_count(s->ptimer_tick);
699     if (count) {
700         /* timer is still counting, called not from event */
701         counted = s->count - ptimer_get_count(s->ptimer_tick);
702         cur_progress = s->progress + counted;
703     } else {
704         /* timer expired earlier */
705         cur_progress = s->progress;
706     }
707 
708     remain = s->distance - cur_progress;
709 
710     if (!s->int_run) {
711         /* INT is stopped. */
712         icnto = s->last_icnto;
713     } else {
714         /* Both are counting */
715         icnto = remain / s->tcntb;
716     }
717 
718     return icnto;
719 }
720 
721 /*
722  * Start local tick cnt timer.
723  */
724 static void exynos4210_ltick_cnt_start(struct tick_timer *s)
725 {
726     if (!s->cnt_run) {
727 
728         exynos4210_ltick_recalc_count(s);
729         ptimer_set_count(s->ptimer_tick, s->count);
730         ptimer_run(s->ptimer_tick, 1);
731 
732         s->cnt_run = 1;
733     }
734 }
735 
736 /*
737  * Stop local tick cnt timer.
738  */
739 static void exynos4210_ltick_cnt_stop(struct tick_timer *s)
740 {
741     if (s->cnt_run) {
742 
743         s->last_tcnto = exynos4210_ltick_cnt_get_cnto(s);
744 
745         if (s->int_run) {
746             exynos4210_ltick_int_stop(s);
747         }
748 
749         ptimer_stop(s->ptimer_tick);
750 
751         s->cnt_run = 0;
752     }
753 }
754 
755 /*
756  * Get counter for CNT timer
757  */
758 static uint32_t exynos4210_ltick_cnt_get_cnto(struct tick_timer *s)
759 {
760     uint32_t tcnto;
761     uint32_t icnto;
762     uint64_t remain;
763     uint64_t counted;
764     uint64_t count;
765     uint64_t cur_progress;
766 
767     count = ptimer_get_count(s->ptimer_tick);
768     if (count) {
769         /* timer is still counting, called not from event */
770         counted = s->count - ptimer_get_count(s->ptimer_tick);
771         cur_progress = s->progress + counted;
772     } else {
773         /* timer expired earlier */
774         cur_progress = s->progress;
775     }
776 
777     remain = s->distance - cur_progress;
778 
779     if (!s->cnt_run) {
780         /* Both are stopped. */
781         tcnto = s->last_tcnto;
782     } else if (!s->int_run) {
783         /* INT counter is stopped, progress is by CNT timer */
784         tcnto = remain % s->tcntb;
785     } else {
786         /* Both are counting */
787         icnto = remain / s->tcntb;
788         if (icnto) {
789             tcnto = remain % (icnto * s->tcntb);
790         } else {
791             tcnto = remain % s->tcntb;
792         }
793     }
794 
795     return tcnto;
796 }
797 
798 /*
799  * Set new values of counters for CNT and INT timers
800  */
801 static void exynos4210_ltick_set_cntb(struct tick_timer *s, uint32_t new_cnt,
802         uint32_t new_int)
803 {
804     uint32_t cnt_stopped = 0;
805     uint32_t int_stopped = 0;
806 
807     if (s->cnt_run) {
808         exynos4210_ltick_cnt_stop(s);
809         cnt_stopped = 1;
810     }
811 
812     if (s->int_run) {
813         exynos4210_ltick_int_stop(s);
814         int_stopped = 1;
815     }
816 
817     s->tcntb = new_cnt + 1;
818     s->icntb = new_int + 1;
819 
820     if (cnt_stopped) {
821         exynos4210_ltick_cnt_start(s);
822     }
823     if (int_stopped) {
824         exynos4210_ltick_int_start(s);
825     }
826 
827 }
828 
829 /*
830  * Calculate new counter value for tick timer
831  */
832 static void exynos4210_ltick_recalc_count(struct tick_timer *s)
833 {
834     uint64_t to_count;
835 
836     if ((s->cnt_run && s->last_tcnto) || (s->int_run && s->last_icnto)) {
837         /*
838          * one or both timers run and not counted to the end;
839          * distance is not passed, recalculate with last_tcnto * last_icnto
840          */
841 
842         if (s->last_tcnto) {
843             to_count = (uint64_t)s->last_tcnto * s->last_icnto;
844         } else {
845             to_count = s->last_icnto;
846         }
847     } else {
848         /* distance is passed, recalculate with tcnto * icnto */
849         if (s->icntb) {
850             s->distance = (uint64_t)s->tcntb * s->icntb;
851         } else {
852             s->distance = s->tcntb;
853         }
854 
855         to_count = s->distance;
856         s->progress = 0;
857     }
858 
859     if (to_count > MCT_LT_COUNTER_STEP) {
860         /* count by step */
861         s->count = MCT_LT_COUNTER_STEP;
862     } else {
863         s->count = to_count;
864     }
865 }
866 
867 /*
868  * Initialize tick_timer
869  */
870 static void exynos4210_ltick_timer_init(struct tick_timer *s)
871 {
872     exynos4210_ltick_int_stop(s);
873     exynos4210_ltick_cnt_stop(s);
874 
875     s->count = 0;
876     s->distance = 0;
877     s->progress = 0;
878     s->icntb = 0;
879     s->tcntb = 0;
880 }
881 
882 /*
883  * tick_timer event.
884  * Raises when abstract tick_timer expires.
885  */
886 static void exynos4210_ltick_timer_event(struct tick_timer *s)
887 {
888     s->progress += s->count;
889 }
890 
891 /*
892  * Local timer tick counter handler.
893  * Don't use reloaded timers. If timer counter = zero
894  * then handler called but after handler finished no
895  * timer reload occurs.
896  */
897 static void exynos4210_ltick_event(void *opaque)
898 {
899     Exynos4210MCTLT * s = (Exynos4210MCTLT *)opaque;
900     uint32_t tcnto;
901     uint32_t icnto;
902 #ifdef DEBUG_MCT
903     static uint64_t time1[2] = {0};
904     static uint64_t time2[2] = {0};
905 #endif
906 
907     /* Call tick_timer event handler, it will update its tcntb and icntb. */
908     exynos4210_ltick_timer_event(&s->tick_timer);
909 
910     /* get tick_timer cnt */
911     tcnto = exynos4210_ltick_cnt_get_cnto(&s->tick_timer);
912 
913     /* get tick_timer int */
914     icnto = exynos4210_ltick_int_get_cnto(&s->tick_timer);
915 
916     /* raise IRQ if needed */
917     if (!icnto && s->reg.tcon & L_TCON_INT_START) {
918         /* INT counter enabled and expired */
919 
920         s->reg.int_cstat |= L_INT_CSTAT_INTCNT;
921 
922         /* raise interrupt if enabled */
923         if (s->reg.int_enb & L_INT_INTENB_ICNTEIE) {
924 #ifdef DEBUG_MCT
925             time2[s->id] = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
926             DPRINTF("local timer[%d] IRQ: %llx\n", s->id,
927                     time2[s->id] - time1[s->id]);
928             time1[s->id] = time2[s->id];
929 #endif
930             qemu_irq_raise(s->irq);
931         }
932 
933         /* reload ICNTB */
934         if (s->reg.tcon & L_TCON_INTERVAL_MODE) {
935             exynos4210_ltick_set_cntb(&s->tick_timer,
936                     s->reg.cnt[L_REG_CNT_TCNTB],
937                     s->reg.cnt[L_REG_CNT_ICNTB]);
938         }
939     } else {
940         /* reload TCNTB */
941         if (!tcnto) {
942             exynos4210_ltick_set_cntb(&s->tick_timer,
943                     s->reg.cnt[L_REG_CNT_TCNTB],
944                     icnto);
945         }
946     }
947 
948     /* start tick_timer cnt */
949     exynos4210_ltick_cnt_start(&s->tick_timer);
950 
951     /* start tick_timer int */
952     exynos4210_ltick_int_start(&s->tick_timer);
953 }
954 
955 static void tx_ptimer_set_freq(ptimer_state *s, uint32_t freq)
956 {
957     /*
958      * callers of exynos4210_mct_update_freq() never do anything
959      * else that needs to be in the same ptimer transaction, so
960      * to avoid a lot of repetition we have a convenience function
961      * for begin/set_freq/commit.
962      */
963     ptimer_transaction_begin(s);
964     ptimer_set_freq(s, freq);
965     ptimer_transaction_commit(s);
966 }
967 
968 /* update timer frequency */
969 static void exynos4210_mct_update_freq(Exynos4210MCTState *s)
970 {
971     uint32_t freq = s->freq;
972     s->freq = 24000000 /
973             ((MCT_CFG_GET_PRESCALER(s->reg_mct_cfg) + 1) *
974                     MCT_CFG_GET_DIVIDER(s->reg_mct_cfg));
975 
976     if (freq != s->freq) {
977         DPRINTF("freq=%dHz\n", s->freq);
978 
979         /* global timer */
980         tx_ptimer_set_freq(s->g_timer.ptimer_frc, s->freq);
981 
982         /* local timer */
983         ptimer_set_freq(s->l_timer[0].tick_timer.ptimer_tick, s->freq);
984         ptimer_set_freq(s->l_timer[0].ptimer_frc, s->freq);
985         ptimer_set_freq(s->l_timer[1].tick_timer.ptimer_tick, s->freq);
986         ptimer_set_freq(s->l_timer[1].ptimer_frc, s->freq);
987     }
988 }
989 
990 /* set defaul_timer values for all fields */
991 static void exynos4210_mct_reset(DeviceState *d)
992 {
993     Exynos4210MCTState *s = EXYNOS4210_MCT(d);
994     uint32_t i;
995 
996     s->reg_mct_cfg = 0;
997 
998     /* global timer */
999     memset(&s->g_timer.reg, 0, sizeof(s->g_timer.reg));
1000     exynos4210_gfrc_tx_begin(&s->g_timer);
1001     exynos4210_gfrc_stop(&s->g_timer);
1002     exynos4210_gfrc_tx_commit(&s->g_timer);
1003 
1004     /* local timer */
1005     memset(s->l_timer[0].reg.cnt, 0, sizeof(s->l_timer[0].reg.cnt));
1006     memset(s->l_timer[1].reg.cnt, 0, sizeof(s->l_timer[1].reg.cnt));
1007     for (i = 0; i < 2; i++) {
1008         s->l_timer[i].reg.int_cstat = 0;
1009         s->l_timer[i].reg.int_enb = 0;
1010         s->l_timer[i].reg.tcon = 0;
1011         s->l_timer[i].reg.wstat = 0;
1012         s->l_timer[i].tick_timer.count = 0;
1013         s->l_timer[i].tick_timer.distance = 0;
1014         s->l_timer[i].tick_timer.progress = 0;
1015         ptimer_stop(s->l_timer[i].ptimer_frc);
1016 
1017         exynos4210_ltick_timer_init(&s->l_timer[i].tick_timer);
1018     }
1019 
1020     exynos4210_mct_update_freq(s);
1021 
1022 }
1023 
1024 /* Multi Core Timer read */
1025 static uint64_t exynos4210_mct_read(void *opaque, hwaddr offset,
1026         unsigned size)
1027 {
1028     Exynos4210MCTState *s = (Exynos4210MCTState *)opaque;
1029     int index;
1030     int shift;
1031     uint64_t count;
1032     uint32_t value;
1033     int lt_i;
1034 
1035     switch (offset) {
1036 
1037     case MCT_CFG:
1038         value = s->reg_mct_cfg;
1039         break;
1040 
1041     case G_CNT_L: case G_CNT_U:
1042         shift = 8 * (offset & 0x4);
1043         count = exynos4210_gfrc_get_count(&s->g_timer);
1044         value = UINT32_MAX & (count >> shift);
1045         DPRINTF("read FRC=0x%llx\n", count);
1046         break;
1047 
1048     case G_CNT_WSTAT:
1049         value = s->g_timer.reg.cnt_wstat;
1050         break;
1051 
1052     case G_COMP_L(0): case G_COMP_L(1): case G_COMP_L(2): case G_COMP_L(3):
1053     case G_COMP_U(0): case G_COMP_U(1): case G_COMP_U(2): case G_COMP_U(3):
1054         index = GET_G_COMP_IDX(offset);
1055         shift = 8 * (offset & 0x4);
1056         value = UINT32_MAX & (s->g_timer.reg.comp[index] >> shift);
1057     break;
1058 
1059     case G_TCON:
1060         value = s->g_timer.reg.tcon;
1061         break;
1062 
1063     case G_INT_CSTAT:
1064         value = s->g_timer.reg.int_cstat;
1065         break;
1066 
1067     case G_INT_ENB:
1068         value = s->g_timer.reg.int_enb;
1069         break;
1070     case G_WSTAT:
1071         value = s->g_timer.reg.wstat;
1072         break;
1073 
1074     case G_COMP0_ADD_INCR: case G_COMP1_ADD_INCR:
1075     case G_COMP2_ADD_INCR: case G_COMP3_ADD_INCR:
1076         value = s->g_timer.reg.comp_add_incr[GET_G_COMP_ADD_INCR_IDX(offset)];
1077         break;
1078 
1079         /* Local timers */
1080     case L0_TCNTB: case L0_ICNTB: case L0_FRCNTB:
1081     case L1_TCNTB: case L1_ICNTB: case L1_FRCNTB:
1082         lt_i = GET_L_TIMER_IDX(offset);
1083         index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i);
1084         value = s->l_timer[lt_i].reg.cnt[index];
1085         break;
1086 
1087     case L0_TCNTO: case L1_TCNTO:
1088         lt_i = GET_L_TIMER_IDX(offset);
1089 
1090         value = exynos4210_ltick_cnt_get_cnto(&s->l_timer[lt_i].tick_timer);
1091         DPRINTF("local timer[%d] read TCNTO %x\n", lt_i, value);
1092         break;
1093 
1094     case L0_ICNTO: case L1_ICNTO:
1095         lt_i = GET_L_TIMER_IDX(offset);
1096 
1097         value = exynos4210_ltick_int_get_cnto(&s->l_timer[lt_i].tick_timer);
1098         DPRINTF("local timer[%d] read ICNTO %x\n", lt_i, value);
1099         break;
1100 
1101     case L0_FRCNTO: case L1_FRCNTO:
1102         lt_i = GET_L_TIMER_IDX(offset);
1103 
1104         value = exynos4210_lfrc_get_count(&s->l_timer[lt_i]);
1105         break;
1106 
1107     case L0_TCON: case L1_TCON:
1108         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1109         value = s->l_timer[lt_i].reg.tcon;
1110         break;
1111 
1112     case L0_INT_CSTAT: case L1_INT_CSTAT:
1113         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1114         value = s->l_timer[lt_i].reg.int_cstat;
1115         break;
1116 
1117     case L0_INT_ENB: case L1_INT_ENB:
1118         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1119         value = s->l_timer[lt_i].reg.int_enb;
1120         break;
1121 
1122     case L0_WSTAT: case L1_WSTAT:
1123         lt_i = ((offset & 0xF00) - L0_TCNTB) / 0x100;
1124         value = s->l_timer[lt_i].reg.wstat;
1125         break;
1126 
1127     default:
1128         hw_error("exynos4210.mct: bad read offset "
1129                 TARGET_FMT_plx "\n", offset);
1130         break;
1131     }
1132     return value;
1133 }
1134 
1135 /* MCT write */
1136 static void exynos4210_mct_write(void *opaque, hwaddr offset,
1137         uint64_t value, unsigned size)
1138 {
1139     Exynos4210MCTState *s = (Exynos4210MCTState *)opaque;
1140     int index;  /* index in buffer which represents register set */
1141     int shift;
1142     int lt_i;
1143     uint64_t new_frc;
1144     uint32_t i;
1145     uint32_t old_val;
1146 #ifdef DEBUG_MCT
1147     static uint32_t icntb_max[2] = {0};
1148     static uint32_t icntb_min[2] = {UINT32_MAX, UINT32_MAX};
1149     static uint32_t tcntb_max[2] = {0};
1150     static uint32_t tcntb_min[2] = {UINT32_MAX, UINT32_MAX};
1151 #endif
1152 
1153     new_frc = s->g_timer.reg.cnt;
1154 
1155     switch (offset) {
1156 
1157     case MCT_CFG:
1158         s->reg_mct_cfg = value;
1159         exynos4210_mct_update_freq(s);
1160         break;
1161 
1162     case G_CNT_L:
1163     case G_CNT_U:
1164         if (offset == G_CNT_L) {
1165 
1166             DPRINTF("global timer write to reg.cntl %llx\n", value);
1167 
1168             new_frc = (s->g_timer.reg.cnt & (uint64_t)UINT32_MAX << 32) + value;
1169             s->g_timer.reg.cnt_wstat |= G_CNT_WSTAT_L;
1170         }
1171         if (offset == G_CNT_U) {
1172 
1173             DPRINTF("global timer write to reg.cntu %llx\n", value);
1174 
1175             new_frc = (s->g_timer.reg.cnt & UINT32_MAX) +
1176                     ((uint64_t)value << 32);
1177             s->g_timer.reg.cnt_wstat |= G_CNT_WSTAT_U;
1178         }
1179 
1180         s->g_timer.reg.cnt = new_frc;
1181         exynos4210_gfrc_tx_begin(&s->g_timer);
1182         exynos4210_gfrc_restart(s);
1183         exynos4210_gfrc_tx_commit(&s->g_timer);
1184         break;
1185 
1186     case G_CNT_WSTAT:
1187         s->g_timer.reg.cnt_wstat &= ~(value);
1188         break;
1189 
1190     case G_COMP_L(0): case G_COMP_L(1): case G_COMP_L(2): case G_COMP_L(3):
1191     case G_COMP_U(0): case G_COMP_U(1): case G_COMP_U(2): case G_COMP_U(3):
1192         index = GET_G_COMP_IDX(offset);
1193         shift = 8 * (offset & 0x4);
1194         s->g_timer.reg.comp[index] =
1195                 (s->g_timer.reg.comp[index] &
1196                 (((uint64_t)UINT32_MAX << 32) >> shift)) +
1197                 (value << shift);
1198 
1199         DPRINTF("comparator %d write 0x%llx val << %d\n", index, value, shift);
1200 
1201         if (offset & 0x4) {
1202             s->g_timer.reg.wstat |= G_WSTAT_COMP_U(index);
1203         } else {
1204             s->g_timer.reg.wstat |= G_WSTAT_COMP_L(index);
1205         }
1206 
1207         exynos4210_gfrc_tx_begin(&s->g_timer);
1208         exynos4210_gfrc_restart(s);
1209         exynos4210_gfrc_tx_commit(&s->g_timer);
1210         break;
1211 
1212     case G_TCON:
1213         old_val = s->g_timer.reg.tcon;
1214         s->g_timer.reg.tcon = value;
1215         s->g_timer.reg.wstat |= G_WSTAT_TCON_WRITE;
1216 
1217         DPRINTF("global timer write to reg.g_tcon %llx\n", value);
1218 
1219         exynos4210_gfrc_tx_begin(&s->g_timer);
1220 
1221         /* Start FRC if transition from disabled to enabled */
1222         if ((value & G_TCON_TIMER_ENABLE) > (old_val &
1223                 G_TCON_TIMER_ENABLE)) {
1224             exynos4210_gfrc_start(&s->g_timer);
1225         }
1226         if ((value & G_TCON_TIMER_ENABLE) < (old_val &
1227                 G_TCON_TIMER_ENABLE)) {
1228             exynos4210_gfrc_stop(&s->g_timer);
1229         }
1230 
1231         /* Start CMP if transition from disabled to enabled */
1232         for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1233             if ((value & G_TCON_COMP_ENABLE(i)) != (old_val &
1234                     G_TCON_COMP_ENABLE(i))) {
1235                 exynos4210_gfrc_restart(s);
1236             }
1237         }
1238 
1239         exynos4210_gfrc_tx_commit(&s->g_timer);
1240         break;
1241 
1242     case G_INT_CSTAT:
1243         s->g_timer.reg.int_cstat &= ~(value);
1244         for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1245             if (value & G_INT_CSTAT_COMP(i)) {
1246                 exynos4210_gcomp_lower_irq(&s->g_timer, i);
1247             }
1248         }
1249         break;
1250 
1251     case G_INT_ENB:
1252         /* Raise IRQ if transition from disabled to enabled and CSTAT pending */
1253         for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1254             if ((value & G_INT_ENABLE(i)) > (s->g_timer.reg.tcon &
1255                     G_INT_ENABLE(i))) {
1256                 if (s->g_timer.reg.int_cstat & G_INT_CSTAT_COMP(i)) {
1257                     exynos4210_gcomp_raise_irq(&s->g_timer, i);
1258                 }
1259             }
1260 
1261             if ((value & G_INT_ENABLE(i)) < (s->g_timer.reg.tcon &
1262                     G_INT_ENABLE(i))) {
1263                 exynos4210_gcomp_lower_irq(&s->g_timer, i);
1264             }
1265         }
1266 
1267         DPRINTF("global timer INT enable %llx\n", value);
1268         s->g_timer.reg.int_enb = value;
1269         break;
1270 
1271     case G_WSTAT:
1272         s->g_timer.reg.wstat &= ~(value);
1273         break;
1274 
1275     case G_COMP0_ADD_INCR: case G_COMP1_ADD_INCR:
1276     case G_COMP2_ADD_INCR: case G_COMP3_ADD_INCR:
1277         index = GET_G_COMP_ADD_INCR_IDX(offset);
1278         s->g_timer.reg.comp_add_incr[index] = value;
1279         s->g_timer.reg.wstat |= G_WSTAT_COMP_ADDINCR(index);
1280         break;
1281 
1282         /* Local timers */
1283     case L0_TCON: case L1_TCON:
1284         lt_i = GET_L_TIMER_IDX(offset);
1285         old_val = s->l_timer[lt_i].reg.tcon;
1286 
1287         s->l_timer[lt_i].reg.wstat |= L_WSTAT_TCON_WRITE;
1288         s->l_timer[lt_i].reg.tcon = value;
1289 
1290         /* Stop local CNT */
1291         if ((value & L_TCON_TICK_START) <
1292                 (old_val & L_TCON_TICK_START)) {
1293             DPRINTF("local timer[%d] stop cnt\n", lt_i);
1294             exynos4210_ltick_cnt_stop(&s->l_timer[lt_i].tick_timer);
1295         }
1296 
1297         /* Stop local INT */
1298         if ((value & L_TCON_INT_START) <
1299                 (old_val & L_TCON_INT_START)) {
1300             DPRINTF("local timer[%d] stop int\n", lt_i);
1301             exynos4210_ltick_int_stop(&s->l_timer[lt_i].tick_timer);
1302         }
1303 
1304         /* Start local CNT */
1305         if ((value & L_TCON_TICK_START) >
1306         (old_val & L_TCON_TICK_START)) {
1307             DPRINTF("local timer[%d] start cnt\n", lt_i);
1308             exynos4210_ltick_cnt_start(&s->l_timer[lt_i].tick_timer);
1309         }
1310 
1311         /* Start local INT */
1312         if ((value & L_TCON_INT_START) >
1313         (old_val & L_TCON_INT_START)) {
1314             DPRINTF("local timer[%d] start int\n", lt_i);
1315             exynos4210_ltick_int_start(&s->l_timer[lt_i].tick_timer);
1316         }
1317 
1318         /* Start or Stop local FRC if TCON changed */
1319         if ((value & L_TCON_FRC_START) >
1320         (s->l_timer[lt_i].reg.tcon & L_TCON_FRC_START)) {
1321             DPRINTF("local timer[%d] start frc\n", lt_i);
1322             exynos4210_lfrc_start(&s->l_timer[lt_i]);
1323         }
1324         if ((value & L_TCON_FRC_START) <
1325                 (s->l_timer[lt_i].reg.tcon & L_TCON_FRC_START)) {
1326             DPRINTF("local timer[%d] stop frc\n", lt_i);
1327             exynos4210_lfrc_stop(&s->l_timer[lt_i]);
1328         }
1329         break;
1330 
1331     case L0_TCNTB: case L1_TCNTB:
1332         lt_i = GET_L_TIMER_IDX(offset);
1333         index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i);
1334 
1335         /*
1336          * TCNTB is updated to internal register only after CNT expired.
1337          * Due to this we should reload timer to nearest moment when CNT is
1338          * expired and then in event handler update tcntb to new TCNTB value.
1339          */
1340         exynos4210_ltick_set_cntb(&s->l_timer[lt_i].tick_timer, value,
1341                 s->l_timer[lt_i].tick_timer.icntb);
1342 
1343         s->l_timer[lt_i].reg.wstat |= L_WSTAT_TCNTB_WRITE;
1344         s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB] = value;
1345 
1346 #ifdef DEBUG_MCT
1347         if (tcntb_min[lt_i] > value) {
1348             tcntb_min[lt_i] = value;
1349         }
1350         if (tcntb_max[lt_i] < value) {
1351             tcntb_max[lt_i] = value;
1352         }
1353         DPRINTF("local timer[%d] TCNTB write %llx; max=%x, min=%x\n",
1354                 lt_i, value, tcntb_max[lt_i], tcntb_min[lt_i]);
1355 #endif
1356         break;
1357 
1358     case L0_ICNTB: case L1_ICNTB:
1359         lt_i = GET_L_TIMER_IDX(offset);
1360         index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i);
1361 
1362         s->l_timer[lt_i].reg.wstat |= L_WSTAT_ICNTB_WRITE;
1363         s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] = value &
1364                 ~L_ICNTB_MANUAL_UPDATE;
1365 
1366         /*
1367          * We need to avoid too small values for TCNTB*ICNTB. If not, IRQ event
1368          * could raise too fast disallowing QEMU to execute target code.
1369          */
1370         if (s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] *
1371             s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB] < MCT_LT_CNT_LOW_LIMIT) {
1372             if (!s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB]) {
1373                 s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] =
1374                         MCT_LT_CNT_LOW_LIMIT;
1375             } else {
1376                 s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] =
1377                         MCT_LT_CNT_LOW_LIMIT /
1378                         s->l_timer[lt_i].reg.cnt[L_REG_CNT_TCNTB];
1379             }
1380         }
1381 
1382         if (value & L_ICNTB_MANUAL_UPDATE) {
1383             exynos4210_ltick_set_cntb(&s->l_timer[lt_i].tick_timer,
1384                     s->l_timer[lt_i].tick_timer.tcntb,
1385                     s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB]);
1386         }
1387 
1388 #ifdef DEBUG_MCT
1389         if (icntb_min[lt_i] > value) {
1390             icntb_min[lt_i] = value;
1391         }
1392         if (icntb_max[lt_i] < value) {
1393             icntb_max[lt_i] = value;
1394         }
1395         DPRINTF("local timer[%d] ICNTB write %llx; max=%x, min=%x\n\n",
1396                 lt_i, value, icntb_max[lt_i], icntb_min[lt_i]);
1397 #endif
1398         break;
1399 
1400     case L0_FRCNTB: case L1_FRCNTB:
1401         lt_i = GET_L_TIMER_IDX(offset);
1402         index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i);
1403 
1404         DPRINTF("local timer[%d] FRCNTB write %llx\n", lt_i, value);
1405 
1406         s->l_timer[lt_i].reg.wstat |= L_WSTAT_FRCCNTB_WRITE;
1407         s->l_timer[lt_i].reg.cnt[L_REG_CNT_FRCCNTB] = value;
1408 
1409         break;
1410 
1411     case L0_TCNTO: case L1_TCNTO:
1412     case L0_ICNTO: case L1_ICNTO:
1413     case L0_FRCNTO: case L1_FRCNTO:
1414         qemu_log_mask(LOG_GUEST_ERROR,
1415                       "exynos4210.mct: write to RO register " TARGET_FMT_plx,
1416                       offset);
1417         break;
1418 
1419     case L0_INT_CSTAT: case L1_INT_CSTAT:
1420         lt_i = GET_L_TIMER_IDX(offset);
1421 
1422         DPRINTF("local timer[%d] CSTAT write %llx\n", lt_i, value);
1423 
1424         s->l_timer[lt_i].reg.int_cstat &= ~value;
1425         if (!s->l_timer[lt_i].reg.int_cstat) {
1426             qemu_irq_lower(s->l_timer[lt_i].irq);
1427         }
1428         break;
1429 
1430     case L0_INT_ENB: case L1_INT_ENB:
1431         lt_i = GET_L_TIMER_IDX(offset);
1432         old_val = s->l_timer[lt_i].reg.int_enb;
1433 
1434         /* Raise Local timer IRQ if cstat is pending */
1435         if ((value & L_INT_INTENB_ICNTEIE) > (old_val & L_INT_INTENB_ICNTEIE)) {
1436             if (s->l_timer[lt_i].reg.int_cstat & L_INT_CSTAT_INTCNT) {
1437                 qemu_irq_raise(s->l_timer[lt_i].irq);
1438             }
1439         }
1440 
1441         s->l_timer[lt_i].reg.int_enb = value;
1442 
1443         break;
1444 
1445     case L0_WSTAT: case L1_WSTAT:
1446         lt_i = GET_L_TIMER_IDX(offset);
1447 
1448         s->l_timer[lt_i].reg.wstat &= ~value;
1449         break;
1450 
1451     default:
1452         hw_error("exynos4210.mct: bad write offset "
1453                 TARGET_FMT_plx "\n", offset);
1454         break;
1455     }
1456 }
1457 
1458 static const MemoryRegionOps exynos4210_mct_ops = {
1459     .read = exynos4210_mct_read,
1460     .write = exynos4210_mct_write,
1461     .endianness = DEVICE_NATIVE_ENDIAN,
1462 };
1463 
1464 /* MCT init */
1465 static void exynos4210_mct_init(Object *obj)
1466 {
1467     int i;
1468     Exynos4210MCTState *s = EXYNOS4210_MCT(obj);
1469     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
1470     QEMUBH *bh[2];
1471 
1472     /* Global timer */
1473     s->g_timer.ptimer_frc = ptimer_init(exynos4210_gfrc_event, s,
1474                                         PTIMER_POLICY_DEFAULT);
1475     memset(&s->g_timer.reg, 0, sizeof(struct gregs));
1476 
1477     /* Local timers */
1478     for (i = 0; i < 2; i++) {
1479         bh[0] = qemu_bh_new(exynos4210_ltick_event, &s->l_timer[i]);
1480         bh[1] = qemu_bh_new(exynos4210_lfrc_event, &s->l_timer[i]);
1481         s->l_timer[i].tick_timer.ptimer_tick =
1482             ptimer_init_with_bh(bh[0], PTIMER_POLICY_DEFAULT);
1483         s->l_timer[i].ptimer_frc =
1484             ptimer_init_with_bh(bh[1], PTIMER_POLICY_DEFAULT);
1485         s->l_timer[i].id = i;
1486     }
1487 
1488     /* IRQs */
1489     for (i = 0; i < MCT_GT_CMP_NUM; i++) {
1490         sysbus_init_irq(dev, &s->g_timer.irq[i]);
1491     }
1492     for (i = 0; i < 2; i++) {
1493         sysbus_init_irq(dev, &s->l_timer[i].irq);
1494     }
1495 
1496     memory_region_init_io(&s->iomem, obj, &exynos4210_mct_ops, s,
1497                           "exynos4210-mct", MCT_SFR_SIZE);
1498     sysbus_init_mmio(dev, &s->iomem);
1499 }
1500 
1501 static void exynos4210_mct_class_init(ObjectClass *klass, void *data)
1502 {
1503     DeviceClass *dc = DEVICE_CLASS(klass);
1504 
1505     dc->reset = exynos4210_mct_reset;
1506     dc->vmsd = &vmstate_exynos4210_mct_state;
1507 }
1508 
1509 static const TypeInfo exynos4210_mct_info = {
1510     .name          = TYPE_EXYNOS4210_MCT,
1511     .parent        = TYPE_SYS_BUS_DEVICE,
1512     .instance_size = sizeof(Exynos4210MCTState),
1513     .instance_init = exynos4210_mct_init,
1514     .class_init    = exynos4210_mct_class_init,
1515 };
1516 
1517 static void exynos4210_mct_register_types(void)
1518 {
1519     type_register_static(&exynos4210_mct_info);
1520 }
1521 
1522 type_init(exynos4210_mct_register_types)
1523