xref: /openbmc/qemu/hw/dma/i82374.c (revision 500eb6db)
1 /*
2  * QEMU Intel 82374 emulation (Enhanced DMA controller)
3  *
4  * Copyright (c) 2010 Hervé Poussineau
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 "qapi/error.h"
27 #include "qemu/module.h"
28 #include "hw/isa/isa.h"
29 #include "hw/dma/i8257.h"
30 
31 #define TYPE_I82374 "i82374"
32 #define I82374(obj) OBJECT_CHECK(I82374State, (obj), TYPE_I82374)
33 
34 //#define DEBUG_I82374
35 
36 #ifdef DEBUG_I82374
37 #define DPRINTF(fmt, ...) \
38 do { fprintf(stderr, "i82374: " fmt , ## __VA_ARGS__); } while (0)
39 #else
40 #define DPRINTF(fmt, ...) \
41 do {} while (0)
42 #endif
43 #define BADF(fmt, ...) \
44 do { fprintf(stderr, "i82374 ERROR: " fmt , ## __VA_ARGS__); } while (0)
45 
46 typedef struct I82374State {
47     ISADevice parent_obj;
48 
49     uint32_t iobase;
50     uint8_t commands[8];
51     PortioList port_list;
52 } I82374State;
53 
54 static const VMStateDescription vmstate_i82374 = {
55     .name = "i82374",
56     .version_id = 0,
57     .minimum_version_id = 0,
58     .fields = (VMStateField[]) {
59         VMSTATE_UINT8_ARRAY(commands, I82374State, 8),
60         VMSTATE_END_OF_LIST()
61     },
62 };
63 
64 static uint32_t i82374_read_isr(void *opaque, uint32_t nport)
65 {
66     uint32_t val = 0;
67 
68     BADF("%s: %08x\n", __func__, nport);
69 
70     DPRINTF("%s: %08x=%08x\n", __func__, nport, val);
71     return val;
72 }
73 
74 static void i82374_write_command(void *opaque, uint32_t nport, uint32_t data)
75 {
76     DPRINTF("%s: %08x=%08x\n", __func__, nport, data);
77 
78     if (data != 0x42) {
79         /* Not Stop S/G command */
80         BADF("%s: %08x=%08x\n", __func__, nport, data);
81     }
82 }
83 
84 static uint32_t i82374_read_status(void *opaque, uint32_t nport)
85 {
86     uint32_t val = 0;
87 
88     BADF("%s: %08x\n", __func__, nport);
89 
90     DPRINTF("%s: %08x=%08x\n", __func__, nport, val);
91     return val;
92 }
93 
94 static void i82374_write_descriptor(void *opaque, uint32_t nport, uint32_t data)
95 {
96     DPRINTF("%s: %08x=%08x\n", __func__, nport, data);
97 
98     BADF("%s: %08x=%08x\n", __func__, nport, data);
99 }
100 
101 static uint32_t i82374_read_descriptor(void *opaque, uint32_t nport)
102 {
103     uint32_t val = 0;
104 
105     BADF("%s: %08x\n", __func__, nport);
106 
107     DPRINTF("%s: %08x=%08x\n", __func__, nport, val);
108     return val;
109 }
110 
111 static const MemoryRegionPortio i82374_portio_list[] = {
112     { 0x0A, 1, 1, .read = i82374_read_isr, },
113     { 0x10, 8, 1, .write = i82374_write_command, },
114     { 0x18, 8, 1, .read = i82374_read_status, },
115     { 0x20, 0x20, 1,
116       .write = i82374_write_descriptor, .read = i82374_read_descriptor, },
117     PORTIO_END_OF_LIST(),
118 };
119 
120 static void i82374_realize(DeviceState *dev, Error **errp)
121 {
122     I82374State *s = I82374(dev);
123     ISABus *isa_bus = isa_bus_from_device(ISA_DEVICE(dev));
124 
125     if (isa_get_dma(isa_bus, 0)) {
126         error_setg(errp, "DMA already initialized on ISA bus");
127         return;
128     }
129     i8257_dma_init(isa_bus, true);
130 
131     portio_list_init(&s->port_list, OBJECT(s), i82374_portio_list, s,
132                      "i82374");
133     portio_list_add(&s->port_list, isa_address_space_io(&s->parent_obj),
134                     s->iobase);
135 
136     memset(s->commands, 0, sizeof(s->commands));
137 }
138 
139 static Property i82374_properties[] = {
140     DEFINE_PROP_UINT32("iobase", I82374State, iobase, 0x400),
141     DEFINE_PROP_END_OF_LIST()
142 };
143 
144 static void i82374_class_init(ObjectClass *klass, void *data)
145 {
146     DeviceClass *dc = DEVICE_CLASS(klass);
147 
148     dc->realize = i82374_realize;
149     dc->vmsd = &vmstate_i82374;
150     dc->props = i82374_properties;
151 }
152 
153 static const TypeInfo i82374_info = {
154     .name  = TYPE_I82374,
155     .parent = TYPE_ISA_DEVICE,
156     .instance_size  = sizeof(I82374State),
157     .class_init = i82374_class_init,
158 };
159 
160 static void i82374_register_types(void)
161 {
162     type_register_static(&i82374_info);
163 }
164 
165 type_init(i82374_register_types)
166