1
2
3
4
5
6
7
8
9
10#include "qemu/osdep.h"
11
12#include "qapi/error.h"
13#include "qemu/module.h"
14#include "hw/i2c/i2c.h"
15#include "hw/nvram/eeprom_at24c.h"
16#include "hw/qdev-properties.h"
17#include "hw/qdev-properties-system.h"
18#include "sysemu/block-backend.h"
19#include "qom/object.h"
20
21
22
23#ifdef DEBUG_AT24C
24#define DPRINTK(FMT, ...) printf(TYPE_AT24C_EE " : " FMT, ## __VA_ARGS__)
25#else
26#define DPRINTK(FMT, ...) do {} while (0)
27#endif
28
29#define ERR(FMT, ...) fprintf(stderr, TYPE_AT24C_EE " : " FMT, \
30 ## __VA_ARGS__)
31
32#define TYPE_AT24C_EE "at24c-eeprom"
33typedef struct EEPROMState EEPROMState;
34DECLARE_INSTANCE_CHECKER(EEPROMState, AT24C_EE,
35 TYPE_AT24C_EE)
36
37struct EEPROMState {
38 I2CSlave parent_obj;
39
40
41 uint16_t cur;
42
43 uint32_t rsize;
44
45
46
47
48
49 uint8_t asize;
50
51 bool writable;
52
53 bool changed;
54
55 uint8_t haveaddr;
56
57 uint8_t *mem;
58
59 BlockBackend *blk;
60
61 const uint8_t *init_rom;
62 uint32_t init_rom_size;
63};
64
65static
66int at24c_eeprom_event(I2CSlave *s, enum i2c_event event)
67{
68 EEPROMState *ee = AT24C_EE(s);
69
70 switch (event) {
71 case I2C_START_SEND:
72 case I2C_FINISH:
73 ee->haveaddr = 0;
74
75 case I2C_START_RECV:
76 DPRINTK("clear\n");
77 if (ee->blk && ee->changed) {
78 int ret = blk_pwrite(ee->blk, 0, ee->rsize, ee->mem, 0);
79 if (ret < 0) {
80 ERR(TYPE_AT24C_EE
81 " : failed to write backing file\n");
82 }
83 DPRINTK("Wrote to backing file\n");
84 }
85 ee->changed = false;
86 break;
87 case I2C_NACK:
88 break;
89 default:
90 return -1;
91 }
92 return 0;
93}
94
95static
96uint8_t at24c_eeprom_recv(I2CSlave *s)
97{
98 EEPROMState *ee = AT24C_EE(s);
99 uint8_t ret;
100
101
102
103
104
105 if (ee->haveaddr > 0 && ee->haveaddr < ee->asize) {
106 return 0xff;
107 }
108
109 ret = ee->mem[ee->cur];
110
111 ee->cur = (ee->cur + 1u) % ee->rsize;
112 DPRINTK("Recv %02x %c\n", ret, ret);
113
114 return ret;
115}
116
117static
118int at24c_eeprom_send(I2CSlave *s, uint8_t data)
119{
120 EEPROMState *ee = AT24C_EE(s);
121
122 if (ee->haveaddr < ee->asize) {
123 ee->cur <<= 8;
124 ee->cur |= data;
125 ee->haveaddr++;
126 if (ee->haveaddr == ee->asize) {
127 ee->cur %= ee->rsize;
128 DPRINTK("Set pointer %04x\n", ee->cur);
129 }
130
131 } else {
132 if (ee->writable) {
133 DPRINTK("Send %02x\n", data);
134 ee->mem[ee->cur] = data;
135 ee->changed = true;
136 } else {
137 DPRINTK("Send error %02x read-only\n", data);
138 }
139 ee->cur = (ee->cur + 1u) % ee->rsize;
140
141 }
142
143 return 0;
144}
145
146I2CSlave *at24c_eeprom_init(I2CBus *bus, uint8_t address, uint32_t rom_size)
147{
148 return at24c_eeprom_init_rom(bus, address, rom_size, NULL, 0);
149}
150
151I2CSlave *at24c_eeprom_init_rom(I2CBus *bus, uint8_t address, uint32_t rom_size,
152 const uint8_t *init_rom, uint32_t init_rom_size)
153{
154 EEPROMState *s;
155
156 s = AT24C_EE(i2c_slave_new(TYPE_AT24C_EE, address));
157
158 qdev_prop_set_uint32(DEVICE(s), "rom-size", rom_size);
159
160
161 s->init_rom = init_rom;
162 s->init_rom_size = init_rom_size;
163
164 i2c_slave_realize_and_unref(I2C_SLAVE(s), bus, &error_abort);
165
166 return I2C_SLAVE(s);
167}
168
169static void at24c_eeprom_realize(DeviceState *dev, Error **errp)
170{
171 EEPROMState *ee = AT24C_EE(dev);
172
173 if (ee->init_rom_size > ee->rsize) {
174 error_setg(errp, "%s: init rom is larger than rom: %u > %u",
175 TYPE_AT24C_EE, ee->init_rom_size, ee->rsize);
176 return;
177 }
178
179 if (ee->blk) {
180 int64_t len = blk_getlength(ee->blk);
181
182 if (len != ee->rsize) {
183 error_setg(errp, "%s: Backing file size %" PRId64 " != %u",
184 TYPE_AT24C_EE, len, ee->rsize);
185 return;
186 }
187
188 if (blk_set_perm(ee->blk, BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE,
189 BLK_PERM_ALL, &error_fatal) < 0)
190 {
191 error_setg(errp, "%s: Backing file incorrect permission",
192 TYPE_AT24C_EE);
193 return;
194 }
195 }
196
197 ee->mem = g_malloc0(ee->rsize);
198 memset(ee->mem, 0, ee->rsize);
199
200 if (ee->init_rom) {
201 memcpy(ee->mem, ee->init_rom, MIN(ee->init_rom_size, ee->rsize));
202 }
203
204 if (ee->blk) {
205 int ret = blk_pread(ee->blk, 0, ee->rsize, ee->mem, 0);
206
207 if (ret < 0) {
208 ERR(TYPE_AT24C_EE
209 " : Failed initial sync with backing file\n");
210 }
211 DPRINTK("Reset read backing file\n");
212 }
213
214
215
216
217
218 if (ee->asize == 0) {
219 if (ee->rsize <= 256) {
220 ee->asize = 1;
221 } else {
222 ee->asize = 2;
223 }
224 }
225}
226
227static
228void at24c_eeprom_reset(DeviceState *state)
229{
230 EEPROMState *ee = AT24C_EE(state);
231
232 ee->changed = false;
233 ee->cur = 0;
234 ee->haveaddr = 0;
235}
236
237static Property at24c_eeprom_props[] = {
238 DEFINE_PROP_UINT32("rom-size", EEPROMState, rsize, 0),
239 DEFINE_PROP_UINT8("address-size", EEPROMState, asize, 0),
240 DEFINE_PROP_BOOL("writable", EEPROMState, writable, true),
241 DEFINE_PROP_DRIVE("drive", EEPROMState, blk),
242 DEFINE_PROP_END_OF_LIST()
243};
244
245static
246void at24c_eeprom_class_init(ObjectClass *klass, void *data)
247{
248 DeviceClass *dc = DEVICE_CLASS(klass);
249 I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);
250
251 dc->realize = &at24c_eeprom_realize;
252 k->event = &at24c_eeprom_event;
253 k->recv = &at24c_eeprom_recv;
254 k->send = &at24c_eeprom_send;
255
256 device_class_set_props(dc, at24c_eeprom_props);
257 dc->reset = at24c_eeprom_reset;
258}
259
260static
261const TypeInfo at24c_eeprom_type = {
262 .name = TYPE_AT24C_EE,
263 .parent = TYPE_I2C_SLAVE,
264 .instance_size = sizeof(EEPROMState),
265 .class_size = sizeof(I2CSlaveClass),
266 .class_init = at24c_eeprom_class_init,
267};
268
269static void at24c_eeprom_register(void)
270{
271 type_register_static(&at24c_eeprom_type);
272}
273
274type_init(at24c_eeprom_register)
275
