aboutsummaryrefslogtreecommitdiff
path: root/hw/i2c/pm_smbus.c
blob: 0b5bb8997684201f71e9b1490b3de592f2c65b2d (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
/*
 * PC SMBus implementation
 * splitted from acpi.c
 *
 * Copyright (c) 2006 Fabrice Bellard
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License version 2 as published by the Free Software Foundation.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see
 * <http://www.gnu.org/licenses/>.
 */
#include "hw/hw.h"
#include "hw/i386/pc.h"
#include "hw/i2c/pm_smbus.h"
#include "hw/i2c/smbus.h"

/* no save/load? */

#define SMBHSTSTS       0x00
#define SMBHSTCNT       0x02
#define SMBHSTCMD       0x03
#define SMBHSTADD       0x04
#define SMBHSTDAT0      0x05
#define SMBHSTDAT1      0x06
#define SMBBLKDAT       0x07

//#define DEBUG

#ifdef DEBUG
# define SMBUS_DPRINTF(format, ...)     printf(format, ## __VA_ARGS__)
#else
# define SMBUS_DPRINTF(format, ...)     do { } while (0)
#endif


static void smb_transaction(PMSMBus *s)
{
    uint8_t prot = (s->smb_ctl >> 2) & 0x07;
    uint8_t read = s->smb_addr & 0x01;
    uint8_t cmd = s->smb_cmd;
    uint8_t addr = s->smb_addr >> 1;
    i2c_bus *bus = s->smbus;

    SMBUS_DPRINTF("SMBus trans addr=0x%02x prot=0x%02x\n", addr, prot);
    switch(prot) {
    case 0x0:
        smbus_quick_command(bus, addr, read);
        break;
    case 0x1:
        if (read) {
            s->smb_data0 = smbus_receive_byte(bus, addr);
        } else {
            smbus_send_byte(bus, addr, cmd);
        }
        break;
    case 0x2:
        if (read) {
            s->smb_data0 = smbus_read_byte(bus, addr, cmd);
        } else {
            smbus_write_byte(bus, addr, cmd, s->smb_data0);
        }
        break;
    case 0x3:
        if (read) {
            uint16_t val;
            val = smbus_read_word(bus, addr, cmd);
            s->smb_data0 = val;
            s->smb_data1 = val >> 8;
        } else {
            smbus_write_word(bus, addr, cmd, (s->smb_data1 << 8) | s->smb_data0);
        }
        break;
    case 0x5:
        if (read) {
            s->smb_data0 = smbus_read_block(bus, addr, cmd, s->smb_data);
        } else {
            smbus_write_block(bus, addr, cmd, s->smb_data, s->smb_data0);
        }
        break;
    default:
        goto error;
    }
    return;

  error:
    s->smb_stat |= 0x04;
}

static void smb_ioport_writeb(void *opaque, hwaddr addr, uint64_t val,
                              unsigned width)
{
    PMSMBus *s = opaque;

    SMBUS_DPRINTF("SMB writeb port=0x%04x val=0x%02x\n", addr, val);
    switch(addr) {
    case SMBHSTSTS:
        s->smb_stat = 0;
        s->smb_index = 0;
        break;
    case SMBHSTCNT:
        s->smb_ctl = val;
        if (val & 0x40)
            smb_transaction(s);
        break;
    case SMBHSTCMD:
        s->smb_cmd = val;
        break;
    case SMBHSTADD:
        s->smb_addr = val;
        break;
    case SMBHSTDAT0:
        s->smb_data0 = val;
        break;
    case SMBHSTDAT1:
        s->smb_data1 = val;
        break;
    case SMBBLKDAT:
        s->smb_data[s->smb_index++] = val;
        if (s->smb_index > 31)
            s->smb_index = 0;
        break;
    default:
        break;
    }
}

static uint64_t smb_ioport_readb(void *opaque, hwaddr addr, unsigned width)
{
    PMSMBus *s = opaque;
    uint32_t val;

    switch(addr) {
    case SMBHSTSTS:
        val = s->smb_stat;
        break;
    case SMBHSTCNT:
        s->smb_index = 0;
        val = s->smb_ctl & 0x1f;
        break;
    case SMBHSTCMD:
        val = s->smb_cmd;
        break;
    case SMBHSTADD:
        val = s->smb_addr;
        break;
    case SMBHSTDAT0:
        val = s->smb_data0;
        break;
    case SMBHSTDAT1:
        val = s->smb_data1;
        break;
    case SMBBLKDAT:
        val = s->smb_data[s->smb_index++];
        if (s->smb_index > 31)
            s->smb_index = 0;
        break;
    default:
        val = 0;
        break;
    }
    SMBUS_DPRINTF("SMB readb port=0x%04x val=0x%02x\n", addr, val);
    return val;
}

static const MemoryRegionOps pm_smbus_ops = {
    .read = smb_ioport_readb,
    .write = smb_ioport_writeb,
    .valid.min_access_size = 1,
    .valid.max_access_size = 1,
    .endianness = DEVICE_LITTLE_ENDIAN,
};

void pm_smbus_init(DeviceState *parent, PMSMBus *smb)
{
    smb->smbus = i2c_init_bus(parent, "i2c");
    memory_region_init_io(&smb->io, &pm_smbus_ops, smb, "pm-smbus", 64);
}