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
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
|
/*
* generic mmc spi driver
*
* Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw>
* Licensed under the GPL-2 or later.
*/
#include <common.h>
#include <malloc.h>
#include <part.h>
#include <mmc.h>
#include <spi.h>
#include <crc.h>
#include <linux/crc7.h>
#include <linux/byteorder/swab.h>
/* MMC/SD in SPI mode reports R1 status always */
#define R1_SPI_IDLE (1 << 0)
#define R1_SPI_ERASE_RESET (1 << 1)
#define R1_SPI_ILLEGAL_COMMAND (1 << 2)
#define R1_SPI_COM_CRC (1 << 3)
#define R1_SPI_ERASE_SEQ (1 << 4)
#define R1_SPI_ADDRESS (1 << 5)
#define R1_SPI_PARAMETER (1 << 6)
/* R1 bit 7 is always zero, reuse this bit for error */
#define R1_SPI_ERROR (1 << 7)
/* Response tokens used to ack each block written: */
#define SPI_MMC_RESPONSE_CODE(x) ((x) & 0x1f)
#define SPI_RESPONSE_ACCEPTED ((2 << 1)|1)
#define SPI_RESPONSE_CRC_ERR ((5 << 1)|1)
#define SPI_RESPONSE_WRITE_ERR ((6 << 1)|1)
/* Read and write blocks start with these tokens and end with crc;
* on error, read tokens act like a subset of R2_SPI_* values.
*/
#define SPI_TOKEN_SINGLE 0xfe /* single block r/w, multiblock read */
#define SPI_TOKEN_MULTI_WRITE 0xfc /* multiblock write */
#define SPI_TOKEN_STOP_TRAN 0xfd /* terminate multiblock write */
/* MMC SPI commands start with a start bit "0" and a transmit bit "1" */
#define MMC_SPI_CMD(x) (0x40 | (x & 0x3f))
/* bus capability */
#define MMC_SPI_VOLTAGE (MMC_VDD_32_33 | MMC_VDD_33_34)
#define MMC_SPI_MIN_CLOCK 400000 /* 400KHz to meet MMC spec */
/* timeout value */
#define CTOUT 8
#define RTOUT 3000000 /* 1 sec */
#define WTOUT 3000000 /* 1 sec */
static uint mmc_spi_sendcmd(struct mmc *mmc, ushort cmdidx, u32 cmdarg)
{
struct spi_slave *spi = mmc->priv;
u8 cmdo[7];
u8 r1;
int i;
cmdo[0] = 0xff;
cmdo[1] = MMC_SPI_CMD(cmdidx);
cmdo[2] = cmdarg >> 24;
cmdo[3] = cmdarg >> 16;
cmdo[4] = cmdarg >> 8;
cmdo[5] = cmdarg;
cmdo[6] = (crc7(0, &cmdo[1], 5) << 1) | 0x01;
spi_xfer(spi, sizeof(cmdo) * 8, cmdo, NULL, 0);
for (i = 0; i < CTOUT; i++) {
spi_xfer(spi, 1 * 8, NULL, &r1, 0);
if (i && (r1 & 0x80) == 0) /* r1 response */
break;
}
debug("%s:cmd%d resp%d %x\n", __func__, cmdidx, i, r1);
return r1;
}
static uint mmc_spi_readdata(struct mmc *mmc, void *xbuf,
u32 bcnt, u32 bsize)
{
struct spi_slave *spi = mmc->priv;
u8 *buf = xbuf;
u8 r1;
u16 crc;
int i;
while (bcnt--) {
for (i = 0; i < RTOUT; i++) {
spi_xfer(spi, 1 * 8, NULL, &r1, 0);
if (r1 != 0xff) /* data token */
break;
}
debug("%s:tok%d %x\n", __func__, i, r1);
if (r1 == SPI_TOKEN_SINGLE) {
spi_xfer(spi, bsize * 8, NULL, buf, 0);
spi_xfer(spi, 2 * 8, NULL, &crc, 0);
#ifdef CONFIG_MMC_SPI_CRC_ON
if (swab16(cyg_crc16(buf, bsize)) != crc) {
debug("%s: CRC error\n", mmc->name);
r1 = R1_SPI_COM_CRC;
break;
}
#endif
r1 = 0;
} else {
r1 = R1_SPI_ERROR;
break;
}
buf += bsize;
}
return r1;
}
static uint mmc_spi_writedata(struct mmc *mmc, const void *xbuf,
u32 bcnt, u32 bsize, int multi)
{
struct spi_slave *spi = mmc->priv;
const u8 *buf = xbuf;
u8 r1;
u16 crc;
u8 tok[2];
int i;
tok[0] = 0xff;
tok[1] = multi ? SPI_TOKEN_MULTI_WRITE : SPI_TOKEN_SINGLE;
while (bcnt--) {
#ifdef CONFIG_MMC_SPI_CRC_ON
crc = swab16(cyg_crc16((u8 *)buf, bsize));
#endif
spi_xfer(spi, 2 * 8, tok, NULL, 0);
spi_xfer(spi, bsize * 8, buf, NULL, 0);
spi_xfer(spi, 2 * 8, &crc, NULL, 0);
for (i = 0; i < CTOUT; i++) {
spi_xfer(spi, 1 * 8, NULL, &r1, 0);
if ((r1 & 0x10) == 0) /* response token */
break;
}
debug("%s:tok%d %x\n", __func__, i, r1);
if (SPI_MMC_RESPONSE_CODE(r1) == SPI_RESPONSE_ACCEPTED) {
for (i = 0; i < WTOUT; i++) { /* wait busy */
spi_xfer(spi, 1 * 8, NULL, &r1, 0);
if (i && r1 == 0xff) {
r1 = 0;
break;
}
}
if (i == WTOUT) {
debug("%s:wtout %x\n", __func__, r1);
r1 = R1_SPI_ERROR;
break;
}
} else {
debug("%s: err %x\n", __func__, r1);
r1 = R1_SPI_COM_CRC;
break;
}
buf += bsize;
}
if (multi && bcnt == -1) { /* stop multi write */
tok[1] = SPI_TOKEN_STOP_TRAN;
spi_xfer(spi, 2 * 8, tok, NULL, 0);
for (i = 0; i < WTOUT; i++) { /* wait busy */
spi_xfer(spi, 1 * 8, NULL, &r1, 0);
if (i && r1 == 0xff) {
r1 = 0;
break;
}
}
if (i == WTOUT) {
debug("%s:wstop %x\n", __func__, r1);
r1 = R1_SPI_ERROR;
}
}
return r1;
}
static int mmc_spi_request(struct mmc *mmc, struct mmc_cmd *cmd,
struct mmc_data *data)
{
struct spi_slave *spi = mmc->priv;
u8 r1;
int i;
int ret = 0;
debug("%s:cmd%d %x %x\n", __func__,
cmd->cmdidx, cmd->resp_type, cmd->cmdarg);
spi_claim_bus(spi);
spi_cs_activate(spi);
r1 = mmc_spi_sendcmd(mmc, cmd->cmdidx, cmd->cmdarg);
if (r1 == 0xff) { /* no response */
ret = NO_CARD_ERR;
goto done;
} else if (r1 & R1_SPI_COM_CRC) {
ret = COMM_ERR;
goto done;
} else if (r1 & ~R1_SPI_IDLE) { /* other errors */
ret = TIMEOUT;
goto done;
} else if (cmd->resp_type == MMC_RSP_R2) {
r1 = mmc_spi_readdata(mmc, cmd->response, 1, 16);
for (i = 0; i < 4; i++)
cmd->response[i] = swab32(cmd->response[i]);
debug("r128 %x %x %x %x\n", cmd->response[0], cmd->response[1],
cmd->response[2], cmd->response[3]);
} else if (!data) {
switch (cmd->cmdidx) {
case SD_CMD_APP_SEND_OP_COND:
case MMC_CMD_SEND_OP_COND:
cmd->response[0] = (r1 & R1_SPI_IDLE) ? 0 : OCR_BUSY;
break;
case SD_CMD_SEND_IF_COND:
case MMC_CMD_SPI_READ_OCR:
spi_xfer(spi, 4 * 8, NULL, cmd->response, 0);
cmd->response[0] = swab32(cmd->response[0]);
debug("r32 %x\n", cmd->response[0]);
break;
case MMC_CMD_SEND_STATUS:
spi_xfer(spi, 1 * 8, NULL, cmd->response, 0);
cmd->response[0] = (cmd->response[0] & 0xff) ?
MMC_STATUS_ERROR : MMC_STATUS_RDY_FOR_DATA;
break;
}
} else {
debug("%s:data %x %x %x\n", __func__,
data->flags, data->blocks, data->blocksize);
if (data->flags == MMC_DATA_READ)
r1 = mmc_spi_readdata(mmc, data->dest,
data->blocks, data->blocksize);
else if (data->flags == MMC_DATA_WRITE)
r1 = mmc_spi_writedata(mmc, data->src,
data->blocks, data->blocksize,
(cmd->cmdidx == MMC_CMD_WRITE_MULTIPLE_BLOCK));
if (r1 & R1_SPI_COM_CRC)
ret = COMM_ERR;
else if (r1) /* other errors */
ret = TIMEOUT;
}
done:
spi_cs_deactivate(spi);
spi_release_bus(spi);
return ret;
}
static void mmc_spi_set_ios(struct mmc *mmc)
{
struct spi_slave *spi = mmc->priv;
debug("%s: clock %u\n", __func__, mmc->clock);
if (mmc->clock)
spi_set_speed(spi, mmc->clock);
}
static int mmc_spi_init_p(struct mmc *mmc)
{
struct spi_slave *spi = mmc->priv;
mmc->clock = 0;
spi_set_speed(spi, MMC_SPI_MIN_CLOCK);
spi_claim_bus(spi);
/* cs deactivated for 100+ clock */
spi_xfer(spi, 18 * 8, NULL, NULL, 0);
spi_release_bus(spi);
return 0;
}
static const struct mmc_ops mmc_spi_ops = {
.send_cmd = mmc_spi_request,
.set_ios = mmc_spi_set_ios,
.init = mmc_spi_init_p,
};
struct mmc *mmc_spi_init(uint bus, uint cs, uint speed, uint mode)
{
struct mmc *mmc;
mmc = malloc(sizeof(*mmc));
if (!mmc)
return NULL;
memset(mmc, 0, sizeof(*mmc));
mmc->priv = spi_setup_slave(bus, cs, speed, mode);
if (!mmc->priv) {
free(mmc);
return NULL;
}
sprintf(mmc->name, "MMC_SPI");
mmc->ops = &mmc_spi_ops;
mmc->host_caps = MMC_MODE_SPI;
mmc->voltages = MMC_SPI_VOLTAGE;
mmc->f_max = speed;
mmc->f_min = MMC_SPI_MIN_CLOCK;
mmc->block_dev.part_type = PART_TYPE_DOS;
mmc_register(mmc);
return mmc;
}
|
