aboutsummaryrefslogtreecommitdiff
path: root/hw/display/dpcd.c
blob: 943002bee5e3fc95a67c3c860c1de8f152486767 (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
/*
 * dpcd.c
 *
 *  Copyright (C) 2015 : GreenSocs Ltd
 *      http://www.greensocs.com/ , email: info@greensocs.com
 *
 *  Developed by :
 *  Frederic Konrad   <fred.konrad@greensocs.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option)any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, see <http://www.gnu.org/licenses/>.
 *
 */

/*
 * This is a simple AUX slave which emulates a connected screen.
 */

#include "qemu/osdep.h"
#include "qemu/log.h"
#include "hw/misc/auxbus.h"
#include "hw/display/dpcd.h"

#ifndef DEBUG_DPCD
#define DEBUG_DPCD 0
#endif

#define DPRINTF(fmt, ...) do {                                                 \
    if (DEBUG_DPCD) {                                                          \
        qemu_log("dpcd: " fmt, ## __VA_ARGS__);                                \
    }                                                                          \
} while (0)

#define DPCD_READABLE_AREA                      0x600

struct DPCDState {
    /*< private >*/
    AUXSlave parent_obj;

    /*< public >*/
    /*
     * The DCPD is 0x7FFFF length but read as 0 after offset 0x5FF.
     */
    uint8_t dpcd_info[DPCD_READABLE_AREA];

    MemoryRegion iomem;
};

static uint64_t dpcd_read(void *opaque, hwaddr offset, unsigned size)
{
    uint8_t ret;
    DPCDState *e = DPCD(opaque);

    if (offset < DPCD_READABLE_AREA) {
        ret = e->dpcd_info[offset];
    } else {
        qemu_log_mask(LOG_GUEST_ERROR, "dpcd: Bad offset 0x%" HWADDR_PRIX "\n",
                                       offset);
        ret = 0;
    }

    DPRINTF("read 0x%" PRIX8 " @0x%" HWADDR_PRIX "\n", ret, offset);
    return ret;
}

static void dpcd_write(void *opaque, hwaddr offset, uint64_t value,
                       unsigned size)
{
    DPCDState *e = DPCD(opaque);

    DPRINTF("write 0x%" PRIX8 " @0x%" HWADDR_PRIX "\n", (uint8_t)value, offset);

    if (offset < DPCD_READABLE_AREA) {
        e->dpcd_info[offset] = value;
    } else {
        qemu_log_mask(LOG_GUEST_ERROR, "dpcd: Bad offset 0x%" HWADDR_PRIX "\n",
                                       offset);
    }
}

static const MemoryRegionOps aux_ops = {
    .read = dpcd_read,
    .write = dpcd_write,
    .valid = {
        .min_access_size = 1,
        .max_access_size = 1,
    },
    .impl = {
        .min_access_size = 1,
        .max_access_size = 1,
    },
};

static void dpcd_reset(DeviceState *dev)
{
    DPCDState *s = DPCD(dev);

    memset(&(s->dpcd_info), 0, sizeof(s->dpcd_info));

    s->dpcd_info[DPCD_REVISION] = DPCD_REV_1_0;
    s->dpcd_info[DPCD_MAX_LINK_RATE] = DPCD_5_4GBPS;
    s->dpcd_info[DPCD_MAX_LANE_COUNT] = DPCD_FOUR_LANES;
    s->dpcd_info[DPCD_RECEIVE_PORT0_CAP_0] = DPCD_EDID_PRESENT;
    /* buffer size */
    s->dpcd_info[DPCD_RECEIVE_PORT0_CAP_1] = 0xFF;

    s->dpcd_info[DPCD_LANE0_1_STATUS] = DPCD_LANE0_CR_DONE
                                      | DPCD_LANE0_CHANNEL_EQ_DONE
                                      | DPCD_LANE0_SYMBOL_LOCKED
                                      | DPCD_LANE1_CR_DONE
                                      | DPCD_LANE1_CHANNEL_EQ_DONE
                                      | DPCD_LANE1_SYMBOL_LOCKED;
    s->dpcd_info[DPCD_LANE2_3_STATUS] = DPCD_LANE2_CR_DONE
                                      | DPCD_LANE2_CHANNEL_EQ_DONE
                                      | DPCD_LANE2_SYMBOL_LOCKED
                                      | DPCD_LANE3_CR_DONE
                                      | DPCD_LANE3_CHANNEL_EQ_DONE
                                      | DPCD_LANE3_SYMBOL_LOCKED;

    s->dpcd_info[DPCD_LANE_ALIGN_STATUS_UPDATED] = DPCD_INTERLANE_ALIGN_DONE;
    s->dpcd_info[DPCD_SINK_STATUS] = DPCD_RECEIVE_PORT_0_STATUS;
}

static void dpcd_init(Object *obj)
{
    DPCDState *s = DPCD(obj);

    memory_region_init_io(&s->iomem, obj, &aux_ops, s, TYPE_DPCD, 0x7FFFF);
    aux_init_mmio(AUX_SLAVE(obj), &s->iomem);
}

static const VMStateDescription vmstate_dpcd = {
    .name = TYPE_DPCD,
    .version_id = 0,
    .minimum_version_id = 0,
    .fields = (VMStateField[]) {
        VMSTATE_UINT8_ARRAY_V(dpcd_info, DPCDState, DPCD_READABLE_AREA, 0),
        VMSTATE_END_OF_LIST()
    }
};

static void dpcd_class_init(ObjectClass *oc, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(oc);

    dc->reset = dpcd_reset;
    dc->vmsd = &vmstate_dpcd;
}

static const TypeInfo dpcd_info = {
    .name          = TYPE_DPCD,
    .parent        = TYPE_AUX_SLAVE,
    .instance_size = sizeof(DPCDState),
    .class_init    = dpcd_class_init,
    .instance_init = dpcd_init,
};

static void dpcd_register_types(void)
{
    type_register_static(&dpcd_info);
}

type_init(dpcd_register_types)