xref: /openbmc/qemu/hw/misc/iosb.c (revision 5f69e42d)
1 /*
2  * QEMU IOSB emulation
3  *
4  * Copyright (c) 2019 Laurent Vivier
5  * Copyright (c) 2022 Mark Cave-Ayland
6  *
7  * SPDX-License-Identifier: GPL-2.0-or-later
8  */
9 
10 #include "qemu/osdep.h"
11 #include "qemu/log.h"
12 #include "migration/vmstate.h"
13 #include "hw/sysbus.h"
14 #include "hw/misc/iosb.h"
15 #include "trace.h"
16 
17 #define IOSB_SIZE          0x2000
18 
19 #define IOSB_CONFIG        0x0
20 #define IOSB_CONFIG2       0x100
21 #define IOSB_SONIC_SCSI    0x200
22 #define IOSB_REVISION      0x300
23 #define IOSB_SCSI_RESID    0x400
24 #define IOSB_BRIGHTNESS    0x500
25 #define IOSB_TIMEOUT       0x600
26 
27 
28 static uint64_t iosb_read(void *opaque, hwaddr addr,
29                           unsigned size)
30 {
31     IOSBState *s = IOSB(opaque);
32     uint64_t val = 0;
33 
34     switch (addr) {
35     case IOSB_CONFIG:
36     case IOSB_CONFIG2:
37     case IOSB_SONIC_SCSI:
38     case IOSB_REVISION:
39     case IOSB_SCSI_RESID:
40     case IOSB_BRIGHTNESS:
41     case IOSB_TIMEOUT:
42         val = s->regs[addr >> 8];
43         break;
44     default:
45         qemu_log_mask(LOG_UNIMP, "IOSB: unimplemented read addr=0x%"PRIx64
46                                  " val=0x%"PRIx64 " size=%d\n",
47                                  addr, val, size);
48     }
49 
50     trace_iosb_read(addr, val, size);
51     return val;
52 }
53 
54 static void iosb_write(void *opaque, hwaddr addr, uint64_t val,
55                        unsigned size)
56 {
57     IOSBState *s = IOSB(opaque);
58 
59     switch (addr) {
60     case IOSB_CONFIG:
61     case IOSB_CONFIG2:
62     case IOSB_SONIC_SCSI:
63     case IOSB_REVISION:
64     case IOSB_SCSI_RESID:
65     case IOSB_BRIGHTNESS:
66     case IOSB_TIMEOUT:
67         s->regs[addr >> 8] = val;
68         break;
69     default:
70         qemu_log_mask(LOG_UNIMP, "IOSB: unimplemented write addr=0x%"PRIx64
71                                  " val=0x%"PRIx64 " size=%d\n",
72                                  addr, val, size);
73     }
74 
75     trace_iosb_write(addr, val, size);
76 }
77 
78 static const MemoryRegionOps iosb_mmio_ops = {
79     .read = iosb_read,
80     .write = iosb_write,
81     .endianness = DEVICE_BIG_ENDIAN,
82 };
83 
84 static void iosb_reset_hold(Object *obj, ResetType type)
85 {
86     IOSBState *s = IOSB(obj);
87 
88     memset(s->regs, 0, sizeof(s->regs));
89 
90     /* BCLK 33 MHz */
91     s->regs[IOSB_CONFIG >> 8] = 1;
92 }
93 
94 static void iosb_init(Object *obj)
95 {
96     IOSBState *s = IOSB(obj);
97     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
98 
99     memory_region_init_io(&s->mem_regs, obj, &iosb_mmio_ops, s, "IOSB",
100                           IOSB_SIZE);
101     sysbus_init_mmio(sbd, &s->mem_regs);
102 }
103 
104 static const VMStateDescription vmstate_iosb = {
105     .name = "IOSB",
106     .version_id = 1,
107     .minimum_version_id = 1,
108     .fields = (const VMStateField[]) {
109         VMSTATE_UINT32_ARRAY(regs, IOSBState, IOSB_REGS),
110         VMSTATE_END_OF_LIST()
111     }
112 };
113 
114 static void iosb_class_init(ObjectClass *oc, void *data)
115 {
116     DeviceClass *dc = DEVICE_CLASS(oc);
117     ResettableClass *rc = RESETTABLE_CLASS(oc);
118 
119     dc->vmsd = &vmstate_iosb;
120     rc->phases.hold = iosb_reset_hold;
121 }
122 
123 static const TypeInfo iosb_info_types[] = {
124     {
125         .name          = TYPE_IOSB,
126         .parent        = TYPE_SYS_BUS_DEVICE,
127         .instance_size = sizeof(IOSBState),
128         .instance_init = iosb_init,
129         .class_init    = iosb_class_init,
130     },
131 };
132 
133 DEFINE_TYPES(iosb_info_types)
134