1 /*
2 * QEMU model of the Xilinx timer block.
3 *
4 * Copyright (c) 2009 Edgar E. Iglesias.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24
25 #include "qemu/osdep.h"
26 #include "hw/sysbus.h"
27 #include "hw/irq.h"
28 #include "hw/ptimer.h"
29 #include "hw/qdev-properties.h"
30 #include "qemu/log.h"
31 #include "qemu/module.h"
32 #include "qom/object.h"
33
34 #define D(x)
35
36 #define R_TCSR 0
37 #define R_TLR 1
38 #define R_TCR 2
39 #define R_MAX 4
40
41 #define TCSR_MDT (1<<0)
42 #define TCSR_UDT (1<<1)
43 #define TCSR_GENT (1<<2)
44 #define TCSR_CAPT (1<<3)
45 #define TCSR_ARHT (1<<4)
46 #define TCSR_LOAD (1<<5)
47 #define TCSR_ENIT (1<<6)
48 #define TCSR_ENT (1<<7)
49 #define TCSR_TINT (1<<8)
50 #define TCSR_PWMA (1<<9)
51 #define TCSR_ENALL (1<<10)
52
53 struct xlx_timer
54 {
55 ptimer_state *ptimer;
56 void *parent;
57 int nr; /* for debug. */
58
59 unsigned long timer_div;
60
61 uint32_t regs[R_MAX];
62 };
63
64 #define TYPE_XILINX_TIMER "xlnx.xps-timer"
65 typedef struct XpsTimerState XpsTimerState;
66 DECLARE_INSTANCE_CHECKER(XpsTimerState, XILINX_TIMER, TYPE_XILINX_TIMER)
67
68 struct XpsTimerState
69 {
70 SysBusDevice parent_obj;
71
72 MemoryRegion mmio;
73 qemu_irq irq;
74 uint8_t one_timer_only;
75 uint32_t freq_hz;
76 struct xlx_timer *timers;
77 };
78
num_timers(XpsTimerState * t)79 static inline unsigned int num_timers(XpsTimerState *t)
80 {
81 return 2 - t->one_timer_only;
82 }
83
timer_from_addr(hwaddr addr)84 static inline unsigned int timer_from_addr(hwaddr addr)
85 {
86 /* Timers get a 4x32bit control reg area each. */
87 return addr >> 2;
88 }
89
timer_update_irq(XpsTimerState * t)90 static void timer_update_irq(XpsTimerState *t)
91 {
92 unsigned int i, irq = 0;
93 uint32_t csr;
94
95 for (i = 0; i < num_timers(t); i++) {
96 csr = t->timers[i].regs[R_TCSR];
97 irq |= (csr & TCSR_TINT) && (csr & TCSR_ENIT);
98 }
99
100 /* All timers within the same slave share a single IRQ line. */
101 qemu_set_irq(t->irq, !!irq);
102 }
103
104 static uint64_t
timer_read(void * opaque,hwaddr addr,unsigned int size)105 timer_read(void *opaque, hwaddr addr, unsigned int size)
106 {
107 XpsTimerState *t = opaque;
108 struct xlx_timer *xt;
109 uint32_t r = 0;
110 unsigned int timer;
111
112 addr >>= 2;
113 timer = timer_from_addr(addr);
114 xt = &t->timers[timer];
115 /* Further decoding to address a specific timers reg. */
116 addr &= 0x3;
117 switch (addr)
118 {
119 case R_TCR:
120 r = ptimer_get_count(xt->ptimer);
121 if (!(xt->regs[R_TCSR] & TCSR_UDT))
122 r = ~r;
123 D(qemu_log("xlx_timer t=%d read counter=%x udt=%d\n",
124 timer, r, xt->regs[R_TCSR] & TCSR_UDT));
125 break;
126 default:
127 if (addr < ARRAY_SIZE(xt->regs))
128 r = xt->regs[addr];
129 break;
130
131 }
132 D(fprintf(stderr, "%s timer=%d %x=%x\n", __func__, timer, addr * 4, r));
133 return r;
134 }
135
136 /* Must be called inside ptimer transaction block */
timer_enable(struct xlx_timer * xt)137 static void timer_enable(struct xlx_timer *xt)
138 {
139 uint64_t count;
140
141 D(fprintf(stderr, "%s timer=%d down=%d\n", __func__,
142 xt->nr, xt->regs[R_TCSR] & TCSR_UDT));
143
144 ptimer_stop(xt->ptimer);
145
146 if (xt->regs[R_TCSR] & TCSR_UDT)
147 count = xt->regs[R_TLR];
148 else
149 count = ~0 - xt->regs[R_TLR];
150 ptimer_set_limit(xt->ptimer, count, 1);
151 ptimer_run(xt->ptimer, 1);
152 }
153
154 static void
timer_write(void * opaque,hwaddr addr,uint64_t val64,unsigned int size)155 timer_write(void *opaque, hwaddr addr,
156 uint64_t val64, unsigned int size)
157 {
158 XpsTimerState *t = opaque;
159 struct xlx_timer *xt;
160 unsigned int timer;
161 uint32_t value = val64;
162
163 addr >>= 2;
164 timer = timer_from_addr(addr);
165 xt = &t->timers[timer];
166 D(fprintf(stderr, "%s addr=%x val=%x (timer=%d off=%d)\n",
167 __func__, addr * 4, value, timer, addr & 3));
168 /* Further decoding to address a specific timers reg. */
169 addr &= 3;
170 switch (addr)
171 {
172 case R_TCSR:
173 if (value & TCSR_TINT)
174 value &= ~TCSR_TINT;
175
176 xt->regs[addr] = value & 0x7ff;
177 if (value & TCSR_ENT) {
178 ptimer_transaction_begin(xt->ptimer);
179 timer_enable(xt);
180 ptimer_transaction_commit(xt->ptimer);
181 }
182 break;
183
184 default:
185 if (addr < ARRAY_SIZE(xt->regs))
186 xt->regs[addr] = value;
187 break;
188 }
189 timer_update_irq(t);
190 }
191
192 static const MemoryRegionOps timer_ops = {
193 .read = timer_read,
194 .write = timer_write,
195 .endianness = DEVICE_NATIVE_ENDIAN,
196 .valid = {
197 .min_access_size = 4,
198 .max_access_size = 4
199 }
200 };
201
timer_hit(void * opaque)202 static void timer_hit(void *opaque)
203 {
204 struct xlx_timer *xt = opaque;
205 XpsTimerState *t = xt->parent;
206 D(fprintf(stderr, "%s %d\n", __func__, xt->nr));
207 xt->regs[R_TCSR] |= TCSR_TINT;
208
209 if (xt->regs[R_TCSR] & TCSR_ARHT)
210 timer_enable(xt);
211 timer_update_irq(t);
212 }
213
xilinx_timer_realize(DeviceState * dev,Error ** errp)214 static void xilinx_timer_realize(DeviceState *dev, Error **errp)
215 {
216 XpsTimerState *t = XILINX_TIMER(dev);
217 unsigned int i;
218
219 /* Init all the ptimers. */
220 t->timers = g_malloc0(sizeof t->timers[0] * num_timers(t));
221 for (i = 0; i < num_timers(t); i++) {
222 struct xlx_timer *xt = &t->timers[i];
223
224 xt->parent = t;
225 xt->nr = i;
226 xt->ptimer = ptimer_init(timer_hit, xt, PTIMER_POLICY_LEGACY);
227 ptimer_transaction_begin(xt->ptimer);
228 ptimer_set_freq(xt->ptimer, t->freq_hz);
229 ptimer_transaction_commit(xt->ptimer);
230 }
231
232 memory_region_init_io(&t->mmio, OBJECT(t), &timer_ops, t, "xlnx.xps-timer",
233 R_MAX * 4 * num_timers(t));
234 sysbus_init_mmio(SYS_BUS_DEVICE(dev), &t->mmio);
235 }
236
xilinx_timer_init(Object * obj)237 static void xilinx_timer_init(Object *obj)
238 {
239 XpsTimerState *t = XILINX_TIMER(obj);
240
241 /* All timers share a single irq line. */
242 sysbus_init_irq(SYS_BUS_DEVICE(obj), &t->irq);
243 }
244
245 static Property xilinx_timer_properties[] = {
246 DEFINE_PROP_UINT32("clock-frequency", XpsTimerState, freq_hz, 62 * 1000000),
247 DEFINE_PROP_UINT8("one-timer-only", XpsTimerState, one_timer_only, 0),
248 DEFINE_PROP_END_OF_LIST(),
249 };
250
xilinx_timer_class_init(ObjectClass * klass,void * data)251 static void xilinx_timer_class_init(ObjectClass *klass, void *data)
252 {
253 DeviceClass *dc = DEVICE_CLASS(klass);
254
255 dc->realize = xilinx_timer_realize;
256 device_class_set_props(dc, xilinx_timer_properties);
257 }
258
259 static const TypeInfo xilinx_timer_info = {
260 .name = TYPE_XILINX_TIMER,
261 .parent = TYPE_SYS_BUS_DEVICE,
262 .instance_size = sizeof(XpsTimerState),
263 .instance_init = xilinx_timer_init,
264 .class_init = xilinx_timer_class_init,
265 };
266
xilinx_timer_register_types(void)267 static void xilinx_timer_register_types(void)
268 {
269 type_register_static(&xilinx_timer_info);
270 }
271
272 type_init(xilinx_timer_register_types)
273