summaryrefslogtreecommitdiffstats
path: root/qemu/hw/timer/xilinx_timer.c
blob: cdb33551740676f5c131a824ab9bfb02283eb5ca (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
/*
 * QEMU model of the Xilinx timer block.
 *
 * Copyright (c) 2009 Edgar E. Iglesias.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include "hw/sysbus.h"
#include "hw/ptimer.h"
#include "qemu/log.h"
#include "qemu/main-loop.h"

#define D(x)

#define R_TCSR     0
#define R_TLR      1
#define R_TCR      2
#define R_MAX      4

#define TCSR_MDT        (1<<0)
#define TCSR_UDT        (1<<1)
#define TCSR_GENT       (1<<2)
#define TCSR_CAPT       (1<<3)
#define TCSR_ARHT       (1<<4)
#define TCSR_LOAD       (1<<5)
#define TCSR_ENIT       (1<<6)
#define TCSR_ENT        (1<<7)
#define TCSR_TINT       (1<<8)
#define TCSR_PWMA       (1<<9)
#define TCSR_ENALL      (1<<10)

struct xlx_timer
{
    QEMUBH *bh;
    ptimer_state *ptimer;
    void *parent;
    int nr; /* for debug.  */

    unsigned long timer_div;

    uint32_t regs[R_MAX];
};

#define TYPE_XILINX_TIMER "xlnx.xps-timer"
#define XILINX_TIMER(obj) \
    OBJECT_CHECK(struct timerblock, (obj), TYPE_XILINX_TIMER)

struct timerblock
{
    SysBusDevice parent_obj;

    MemoryRegion mmio;
    qemu_irq irq;
    uint8_t one_timer_only;
    uint32_t freq_hz;
    struct xlx_timer *timers;
};

static inline unsigned int num_timers(struct timerblock *t)
{
    return 2 - t->one_timer_only;
}

static inline unsigned int timer_from_addr(hwaddr addr)
{
    /* Timers get a 4x32bit control reg area each.  */
    return addr >> 2;
}

static void timer_update_irq(struct timerblock *t)
{
    unsigned int i, irq = 0;
    uint32_t csr;

    for (i = 0; i < num_timers(t); i++) {
        csr = t->timers[i].regs[R_TCSR];
        irq |= (csr & TCSR_TINT) && (csr & TCSR_ENIT);
    }

    /* All timers within the same slave share a single IRQ line.  */
    qemu_set_irq(t->irq, !!irq);
}

static uint64_t
timer_read(void *opaque, hwaddr addr, unsigned int size)
{
    struct timerblock *t = opaque;
    struct xlx_timer *xt;
    uint32_t r = 0;
    unsigned int timer;

    addr >>= 2;
    timer = timer_from_addr(addr);
    xt = &t->timers[timer];
    /* Further decoding to address a specific timers reg.  */
    addr &= 0x3;
    switch (addr)
    {
        case R_TCR:
                r = ptimer_get_count(xt->ptimer);
                if (!(xt->regs[R_TCSR] & TCSR_UDT))
                    r = ~r;
                D(qemu_log("xlx_timer t=%d read counter=%x udt=%d\n",
                         timer, r, xt->regs[R_TCSR] & TCSR_UDT));
            break;
        default:
            if (addr < ARRAY_SIZE(xt->regs))
                r = xt->regs[addr];
            break;

    }
    D(fprintf(stderr, "%s timer=%d %x=%x\n", __func__, timer, addr * 4, r));
    return r;
}

static void timer_enable(struct xlx_timer *xt)
{
    uint64_t count;

    D(fprintf(stderr, "%s timer=%d down=%d\n", __func__,
              xt->nr, xt->regs[R_TCSR] & TCSR_UDT));

    ptimer_stop(xt->ptimer);

    if (xt->regs[R_TCSR] & TCSR_UDT)
        count = xt->regs[R_TLR];
    else
        count = ~0 - xt->regs[R_TLR];
    ptimer_set_limit(xt->ptimer, count, 1);
    ptimer_run(xt->ptimer, 1);
}

static void
timer_write(void *opaque, hwaddr addr,
            uint64_t val64, unsigned int size)
{
    struct timerblock *t = opaque;
    struct xlx_timer *xt;
    unsigned int timer;
    uint32_t value = val64;

    addr >>= 2;
    timer = timer_from_addr(addr);
    xt = &t->timers[timer];
    D(fprintf(stderr, "%s addr=%x val=%x (timer=%d off=%d)\n",
             __func__, addr * 4, value, timer, addr & 3));
    /* Further decoding to address a specific timers reg.  */
    addr &= 3;
    switch (addr) 
    {
        case R_TCSR:
            if (value & TCSR_TINT)
                value &= ~TCSR_TINT;

            xt->regs[addr] = value & 0x7ff;
            if (value & TCSR_ENT)
                timer_enable(xt);
            break;
 
        default:
            if (addr < ARRAY_SIZE(xt->regs))
                xt->regs[addr] = value;
            break;
    }
    timer_update_irq(t);
}

static const MemoryRegionOps timer_ops = {
    .read = timer_read,
    .write = timer_write,
    .endianness = DEVICE_NATIVE_ENDIAN,
    .valid = {
        .min_access_size = 4,
        .max_access_size = 4
    }
};

static void timer_hit(void *opaque)
{
    struct xlx_timer *xt = opaque;
    struct timerblock *t = xt->parent;
    D(fprintf(stderr, "%s %d\n", __func__, xt->nr));
    xt->regs[R_TCSR] |= TCSR_TINT;

    if (xt->regs[R_TCSR] & TCSR_ARHT)
        timer_enable(xt);
    timer_update_irq(t);
}

static void xilinx_timer_realize(DeviceState *dev, Error **errp)
{
    struct timerblock *t = XILINX_TIMER(dev);
    unsigned int i;

    /* Init all the ptimers.  */
    t->timers = g_malloc0(sizeof t->timers[0] * num_timers(t));
    for (i = 0; i < num_timers(t); i++) {
        struct xlx_timer *xt = &t->timers[i];

        xt->parent = t;
        xt->nr = i;
        xt->bh = qemu_bh_new(timer_hit, xt);
        xt->ptimer = ptimer_init(xt->bh);
        ptimer_set_freq(xt->ptimer, t->freq_hz);
    }

    memory_region_init_io(&t->mmio, OBJECT(t), &timer_ops, t, "xlnx.xps-timer",
                          R_MAX * 4 * num_timers(t));
    sysbus_init_mmio(SYS_BUS_DEVICE(dev), &t->mmio);
}

static void xilinx_timer_init(Object *obj)
{
    struct timerblock *t = XILINX_TIMER(obj);

    /* All timers share a single irq line.  */
    sysbus_init_irq(SYS_BUS_DEVICE(obj), &t->irq);
}

static Property xilinx_timer_properties[] = {
    DEFINE_PROP_UINT32("clock-frequency", struct timerblock, freq_hz,
                                                                62 * 1000000),
    DEFINE_PROP_UINT8("one-timer-only", struct timerblock, one_timer_only, 0),
    DEFINE_PROP_END_OF_LIST(),
};

static void xilinx_timer_class_init(ObjectClass *klass, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(klass);

    dc->realize = xilinx_timer_realize;
    dc->props = xilinx_timer_properties;
}

static const TypeInfo xilinx_timer_info = {
    .name          = TYPE_XILINX_TIMER,
    .parent        = TYPE_SYS_BUS_DEVICE,
    .instance_size = sizeof(struct timerblock),
    .instance_init = xilinx_timer_init,
    .class_init    = xilinx_timer_class_init,
};

static void xilinx_timer_register_types(void)
{
    type_register_static(&xilinx_timer_info);
}

type_init(xilinx_timer_register_types)