1/*
2 * dpcd.c
3 *
4 * Copyright (C) 2015 : GreenSocs Ltd
5 * http://www.greensocs.com/ , email: info@greensocs.com
6 *
7 * Developed by :
8 * Frederic Konrad <fred.konrad@greensocs.com>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation, either version 2 of the License, or
13 * (at your option)any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License along
21 * with this program; if not, see <http://www.gnu.org/licenses/>.
22 *
23 */
24
25/*
26 * This is a simple AUX slave which emulates a connected screen.
27 */
28
29#include "qemu/osdep.h"
30#include "qemu/log.h"
31#include "qemu/module.h"
32#include "hw/misc/auxbus.h"
33#include "migration/vmstate.h"
34#include "hw/display/dpcd.h"
35
36#ifndef DEBUG_DPCD
37#define DEBUG_DPCD 0
38#endif
39
40#define DPRINTF(fmt, ...) do { \
41 if (DEBUG_DPCD) { \
42 qemu_log("dpcd: " fmt, ## __VA_ARGS__); \
43 } \
44} while (0)
45
46#define DPCD_READABLE_AREA 0x600
47
48struct DPCDState {
49 /*< private >*/
50 AUXSlave parent_obj;
51
52 /*< public >*/
53 /*
54 * The DCPD is 0x7FFFF length but read as 0 after offset 0x5FF.
55 */
56 uint8_t dpcd_info[DPCD_READABLE_AREA];
57
58 MemoryRegion iomem;
59};
60
61static uint64_t dpcd_read(void *opaque, hwaddr offset, unsigned size)
62{
63 uint8_t ret;
64 DPCDState *e = DPCD(opaque);
65
66 if (offset < DPCD_READABLE_AREA) {
67 ret = e->dpcd_info[offset];
68 } else {
69 qemu_log_mask(LOG_GUEST_ERROR, "dpcd: Bad offset 0x%" HWADDR_PRIX "\n",
70 offset);
71 ret = 0;
72 }
73
74 DPRINTF("read 0x%" PRIX8 " @0x%" HWADDR_PRIX "\n", ret, offset);
75 return ret;
76}
77
78static void dpcd_write(void *opaque, hwaddr offset, uint64_t value,
79 unsigned size)
80{
81 DPCDState *e = DPCD(opaque);
82
83 DPRINTF("write 0x%" PRIX8 " @0x%" HWADDR_PRIX "\n", (uint8_t)value, offset);
84
85 if (offset < DPCD_READABLE_AREA) {
86 e->dpcd_info[offset] = value;
87 } else {
88 qemu_log_mask(LOG_GUEST_ERROR, "dpcd: Bad offset 0x%" HWADDR_PRIX "\n",
89 offset);
90 }
91}
92
93static const MemoryRegionOps aux_ops = {
94 .read = dpcd_read,
95 .write = dpcd_write,
96 .valid = {
97 .min_access_size = 1,
98 .max_access_size = 1,
99 },
100 .impl = {
101 .min_access_size = 1,
102 .max_access_size = 1,
103 },
104};
105
106static void dpcd_reset(DeviceState *dev)
107{
108 DPCDState *s = DPCD(dev);
109
110 memset(&(s->dpcd_info), 0, sizeof(s->dpcd_info));
111
112 s->dpcd_info[DPCD_REVISION] = DPCD_REV_1_0;
113 s->dpcd_info[DPCD_MAX_LINK_RATE] = DPCD_5_4GBPS;
114 s->dpcd_info[DPCD_MAX_LANE_COUNT] = DPCD_FOUR_LANES;
115 s->dpcd_info[DPCD_RECEIVE_PORT0_CAP_0] = DPCD_EDID_PRESENT;
116 /* buffer size */
117 s->dpcd_info[DPCD_RECEIVE_PORT0_CAP_1] = 0xFF;
118
119 s->dpcd_info[DPCD_LANE0_1_STATUS] = DPCD_LANE0_CR_DONE
120 | DPCD_LANE0_CHANNEL_EQ_DONE
121 | DPCD_LANE0_SYMBOL_LOCKED
122 | DPCD_LANE1_CR_DONE
123 | DPCD_LANE1_CHANNEL_EQ_DONE
124 | DPCD_LANE1_SYMBOL_LOCKED;
125 s->dpcd_info[DPCD_LANE2_3_STATUS] = DPCD_LANE2_CR_DONE
126 | DPCD_LANE2_CHANNEL_EQ_DONE
127 | DPCD_LANE2_SYMBOL_LOCKED
128 | DPCD_LANE3_CR_DONE
129 | DPCD_LANE3_CHANNEL_EQ_DONE
130 | DPCD_LANE3_SYMBOL_LOCKED;
131
132 s->dpcd_info[DPCD_LANE_ALIGN_STATUS_UPDATED] = DPCD_INTERLANE_ALIGN_DONE;
133 s->dpcd_info[DPCD_SINK_STATUS] = DPCD_RECEIVE_PORT_0_STATUS;
134}
135
136static void dpcd_init(Object *obj)
137{
138 DPCDState *s = DPCD(obj);
139
140 memory_region_init_io(&s->iomem, obj, &aux_ops, s, TYPE_DPCD, 0x7FFFF);
141 aux_init_mmio(AUX_SLAVE(obj), &s->iomem);
142}
143
144static const VMStateDescription vmstate_dpcd = {
145 .name = TYPE_DPCD,
146 .version_id = 0,
147 .minimum_version_id = 0,
148 .fields = (VMStateField[]) {
149 VMSTATE_UINT8_ARRAY_V(dpcd_info, DPCDState, DPCD_READABLE_AREA, 0),
150 VMSTATE_END_OF_LIST()
151 }
152};
153
154static void dpcd_class_init(ObjectClass *oc, void *data)
155{
156 DeviceClass *dc = DEVICE_CLASS(oc);
157
158 dc->reset = dpcd_reset;
159 dc->vmsd = &vmstate_dpcd;
160}
161
162static const TypeInfo dpcd_info = {
163 .name = TYPE_DPCD,
164 .parent = TYPE_AUX_SLAVE,
165 .instance_size = sizeof(DPCDState),
166 .class_init = dpcd_class_init,
167 .instance_init = dpcd_init,
168};
169
170static void dpcd_register_types(void)
171{
172 type_register_static(&dpcd_info);
173}
174
175type_init(dpcd_register_types)
176