1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 2016 Imagination Technologies
7 */
8
9 #include "qemu/osdep.h"
10 #include "qemu/timer.h"
11 #include "hw/timer/mips_gictimer.h"
12
13 #define TIMER_PERIOD 10 /* 10 ns period for 100 Mhz frequency */
14
mips_gictimer_get_freq(MIPSGICTimerState * gic)15 uint32_t mips_gictimer_get_freq(MIPSGICTimerState *gic)
16 {
17 return NANOSECONDS_PER_SECOND / TIMER_PERIOD;
18 }
19
gic_vptimer_update(MIPSGICTimerState * gictimer,uint32_t vp_index,uint64_t now)20 static void gic_vptimer_update(MIPSGICTimerState *gictimer,
21 uint32_t vp_index, uint64_t now)
22 {
23 uint64_t next;
24 uint32_t wait;
25
26 wait = gictimer->vptimers[vp_index].comparelo - gictimer->sh_counterlo -
27 (uint32_t)(now / TIMER_PERIOD);
28 next = now + (uint64_t)wait * TIMER_PERIOD;
29
30 timer_mod(gictimer->vptimers[vp_index].qtimer, next);
31 }
32
gic_vptimer_expire(MIPSGICTimerState * gictimer,uint32_t vp_index,uint64_t now)33 static void gic_vptimer_expire(MIPSGICTimerState *gictimer, uint32_t vp_index,
34 uint64_t now)
35 {
36 if (gictimer->countstop) {
37 /* timer stopped */
38 return;
39 }
40 gictimer->cb(gictimer->opaque, vp_index);
41 gic_vptimer_update(gictimer, vp_index, now);
42 }
43
gic_vptimer_cb(void * opaque)44 static void gic_vptimer_cb(void *opaque)
45 {
46 MIPSGICTimerVPState *vptimer = opaque;
47 MIPSGICTimerState *gictimer = vptimer->gictimer;
48 gic_vptimer_expire(gictimer, vptimer->vp_index,
49 qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
50 }
51
mips_gictimer_get_sh_count(MIPSGICTimerState * gictimer)52 uint32_t mips_gictimer_get_sh_count(MIPSGICTimerState *gictimer)
53 {
54 int i;
55 if (gictimer->countstop) {
56 return gictimer->sh_counterlo;
57 } else {
58 uint64_t now;
59 now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
60 for (i = 0; i < gictimer->num_vps; i++) {
61 if (timer_pending(gictimer->vptimers[i].qtimer)
62 && timer_expired(gictimer->vptimers[i].qtimer, now)) {
63 /* The timer has already expired. */
64 gic_vptimer_expire(gictimer, i, now);
65 }
66 }
67 return gictimer->sh_counterlo + (uint32_t)(now / TIMER_PERIOD);
68 }
69 }
70
mips_gictimer_store_sh_count(MIPSGICTimerState * gictimer,uint64_t count)71 void mips_gictimer_store_sh_count(MIPSGICTimerState *gictimer, uint64_t count)
72 {
73 int i;
74 uint64_t now;
75
76 if (gictimer->countstop || !gictimer->vptimers[0].qtimer) {
77 gictimer->sh_counterlo = count;
78 } else {
79 /* Store new count register */
80 now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
81 gictimer->sh_counterlo = count - (uint32_t)(now / TIMER_PERIOD);
82 /* Update timer timer */
83 for (i = 0; i < gictimer->num_vps; i++) {
84 gic_vptimer_update(gictimer, i, now);
85 }
86 }
87 }
88
mips_gictimer_get_vp_compare(MIPSGICTimerState * gictimer,uint32_t vp_index)89 uint32_t mips_gictimer_get_vp_compare(MIPSGICTimerState *gictimer,
90 uint32_t vp_index)
91 {
92 return gictimer->vptimers[vp_index].comparelo;
93 }
94
mips_gictimer_store_vp_compare(MIPSGICTimerState * gictimer,uint32_t vp_index,uint64_t compare)95 void mips_gictimer_store_vp_compare(MIPSGICTimerState *gictimer,
96 uint32_t vp_index, uint64_t compare)
97 {
98 gictimer->vptimers[vp_index].comparelo = (uint32_t) compare;
99 gic_vptimer_update(gictimer, vp_index,
100 qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
101 }
102
mips_gictimer_get_countstop(MIPSGICTimerState * gictimer)103 uint8_t mips_gictimer_get_countstop(MIPSGICTimerState *gictimer)
104 {
105 return gictimer->countstop;
106 }
107
mips_gictimer_start_count(MIPSGICTimerState * gictimer)108 void mips_gictimer_start_count(MIPSGICTimerState *gictimer)
109 {
110 gictimer->countstop = 0;
111 mips_gictimer_store_sh_count(gictimer, gictimer->sh_counterlo);
112 }
113
mips_gictimer_stop_count(MIPSGICTimerState * gictimer)114 void mips_gictimer_stop_count(MIPSGICTimerState *gictimer)
115 {
116 int i;
117
118 gictimer->countstop = 1;
119 /* Store the current value */
120 gictimer->sh_counterlo +=
121 (uint32_t)(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) / TIMER_PERIOD);
122 for (i = 0; i < gictimer->num_vps; i++) {
123 timer_del(gictimer->vptimers[i].qtimer);
124 }
125 }
126
mips_gictimer_init(void * opaque,uint32_t nvps,MIPSGICTimerCB * cb)127 MIPSGICTimerState *mips_gictimer_init(void *opaque, uint32_t nvps,
128 MIPSGICTimerCB *cb)
129 {
130 int i;
131 MIPSGICTimerState *gictimer = g_new(MIPSGICTimerState, 1);
132 gictimer->vptimers = g_new(MIPSGICTimerVPState, nvps);
133 gictimer->countstop = 1;
134 gictimer->num_vps = nvps;
135 gictimer->opaque = opaque;
136 gictimer->cb = cb;
137 for (i = 0; i < nvps; i++) {
138 gictimer->vptimers[i].gictimer = gictimer;
139 gictimer->vptimers[i].vp_index = i;
140 gictimer->vptimers[i].qtimer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
141 &gic_vptimer_cb,
142 &gictimer->vptimers[i]);
143 }
144 return gictimer;
145 }
146