xref: /openbmc/qemu/hw/sd/ssi-sd.c (revision 0ea0538f)
1 /*
2  * SSI to SD card adapter.
3  *
4  * Copyright (c) 2007-2009 CodeSourcery.
5  * Written by Paul Brook
6  *
7  * Copyright (c) 2021 Wind River Systems, Inc.
8  * Improved by Bin Meng <bin.meng@windriver.com>
9  *
10  * Validated with U-Boot v2021.01 and Linux v5.10 mmc_spi driver
11  *
12  * This code is licensed under the GNU GPL v2.
13  *
14  * Contributions after 2012-01-13 are licensed under the terms of the
15  * GNU GPL, version 2 or (at your option) any later version.
16  */
17 
18 #include "qemu/osdep.h"
19 #include "sysemu/blockdev.h"
20 #include "hw/ssi/ssi.h"
21 #include "migration/vmstate.h"
22 #include "hw/qdev-properties.h"
23 #include "hw/sd/sd.h"
24 #include "qapi/error.h"
25 #include "qemu/crc-ccitt.h"
26 #include "qemu/module.h"
27 #include "qom/object.h"
28 
29 //#define DEBUG_SSI_SD 1
30 
31 #ifdef DEBUG_SSI_SD
32 #define DPRINTF(fmt, ...) \
33 do { printf("ssi_sd: " fmt , ## __VA_ARGS__); } while (0)
34 #define BADF(fmt, ...) \
35 do { fprintf(stderr, "ssi_sd: error: " fmt , ## __VA_ARGS__); exit(1);} while (0)
36 #else
37 #define DPRINTF(fmt, ...) do {} while(0)
38 #define BADF(fmt, ...) \
39 do { fprintf(stderr, "ssi_sd: error: " fmt , ## __VA_ARGS__);} while (0)
40 #endif
41 
42 typedef enum {
43     SSI_SD_CMD = 0,
44     SSI_SD_CMDARG,
45     SSI_SD_PREP_RESP,
46     SSI_SD_RESPONSE,
47     SSI_SD_PREP_DATA,
48     SSI_SD_DATA_START,
49     SSI_SD_DATA_READ,
50     SSI_SD_DATA_CRC16,
51     SSI_SD_DATA_WRITE,
52     SSI_SD_SKIP_CRC16,
53 } ssi_sd_mode;
54 
55 struct ssi_sd_state {
56     SSIPeripheral ssidev;
57     uint32_t mode;
58     int cmd;
59     uint8_t cmdarg[4];
60     uint8_t response[5];
61     uint16_t crc16;
62     int32_t read_bytes;
63     int32_t write_bytes;
64     int32_t arglen;
65     int32_t response_pos;
66     int32_t stopping;
67     SDBus sdbus;
68 };
69 
70 #define TYPE_SSI_SD "ssi-sd"
71 OBJECT_DECLARE_SIMPLE_TYPE(ssi_sd_state, SSI_SD)
72 
73 /* State word bits.  */
74 #define SSI_SDR_LOCKED          0x0001
75 #define SSI_SDR_WP_ERASE        0x0002
76 #define SSI_SDR_ERROR           0x0004
77 #define SSI_SDR_CC_ERROR        0x0008
78 #define SSI_SDR_ECC_FAILED      0x0010
79 #define SSI_SDR_WP_VIOLATION    0x0020
80 #define SSI_SDR_ERASE_PARAM     0x0040
81 #define SSI_SDR_OUT_OF_RANGE    0x0080
82 #define SSI_SDR_IDLE            0x0100
83 #define SSI_SDR_ERASE_RESET     0x0200
84 #define SSI_SDR_ILLEGAL_COMMAND 0x0400
85 #define SSI_SDR_COM_CRC_ERROR   0x0800
86 #define SSI_SDR_ERASE_SEQ_ERROR 0x1000
87 #define SSI_SDR_ADDRESS_ERROR   0x2000
88 #define SSI_SDR_PARAMETER_ERROR 0x4000
89 
90 /* multiple block write */
91 #define SSI_TOKEN_MULTI_WRITE   0xfc
92 /* terminate multiple block write */
93 #define SSI_TOKEN_STOP_TRAN     0xfd
94 /* single block read/write, multiple block read */
95 #define SSI_TOKEN_SINGLE        0xfe
96 
97 /* dummy value - don't care */
98 #define SSI_DUMMY               0xff
99 
100 /* data accepted */
101 #define DATA_RESPONSE_ACCEPTED  0x05
102 
103 static uint32_t ssi_sd_transfer(SSIPeripheral *dev, uint32_t val)
104 {
105     ssi_sd_state *s = SSI_SD(dev);
106     SDRequest request;
107     uint8_t longresp[16];
108 
109     /*
110      * Special case: allow CMD12 (STOP TRANSMISSION) while reading data.
111      *
112      * See "Physical Layer Specification Version 8.00" chapter 7.5.2.2,
113      * to avoid conflict between CMD12 response and next data block,
114      * timing of CMD12 should be controlled as follows:
115      *
116      * - CMD12 issued at the timing that end bit of CMD12 and end bit of
117      *   data block is overlapped
118      * - CMD12 issued after one clock cycle after host receives a token
119      *   (either Start Block token or Data Error token)
120      *
121      * We need to catch CMD12 in all of the data read states.
122      */
123     if (s->mode >= SSI_SD_PREP_DATA && s->mode <= SSI_SD_DATA_CRC16) {
124         if (val == 0x4c) {
125             s->mode = SSI_SD_CMD;
126             /* There must be at least one byte delay before the card responds */
127             s->stopping = 1;
128         }
129     }
130 
131     switch (s->mode) {
132     case SSI_SD_CMD:
133         switch (val) {
134         case SSI_DUMMY:
135             DPRINTF("NULL command\n");
136             return SSI_DUMMY;
137             break;
138         case SSI_TOKEN_SINGLE:
139         case SSI_TOKEN_MULTI_WRITE:
140             DPRINTF("Start write block\n");
141             s->mode = SSI_SD_DATA_WRITE;
142             return SSI_DUMMY;
143         case SSI_TOKEN_STOP_TRAN:
144             DPRINTF("Stop multiple write\n");
145 
146             /* manually issue cmd12 to stop the transfer */
147             request.cmd = 12;
148             request.arg = 0;
149             s->arglen = sdbus_do_command(&s->sdbus, &request, longresp);
150             if (s->arglen <= 0) {
151                 s->arglen = 1;
152                 /* a zero value indicates the card is busy */
153                 s->response[0] = 0;
154                 DPRINTF("SD card busy\n");
155             } else {
156                 s->arglen = 1;
157                 /* a non-zero value indicates the card is ready */
158                 s->response[0] = SSI_DUMMY;
159             }
160 
161             return SSI_DUMMY;
162         }
163 
164         s->cmd = val & 0x3f;
165         s->mode = SSI_SD_CMDARG;
166         s->arglen = 0;
167         return SSI_DUMMY;
168     case SSI_SD_CMDARG:
169         if (s->arglen == 4) {
170             /* FIXME: Check CRC.  */
171             request.cmd = s->cmd;
172             request.arg = ldl_be_p(s->cmdarg);
173             DPRINTF("CMD%d arg 0x%08x\n", s->cmd, request.arg);
174             s->arglen = sdbus_do_command(&s->sdbus, &request, longresp);
175             if (s->arglen <= 0) {
176                 s->arglen = 1;
177                 s->response[0] = 4;
178                 DPRINTF("SD command failed\n");
179             } else if (s->cmd == 8 || s->cmd == 58) {
180                 /* CMD8/CMD58 returns R3/R7 response */
181                 DPRINTF("Returned R3/R7\n");
182                 s->arglen = 5;
183                 s->response[0] = 1;
184                 memcpy(&s->response[1], longresp, 4);
185             } else if (s->arglen != 4) {
186                 BADF("Unexpected response to cmd %d\n", s->cmd);
187                 /* Illegal command is about as near as we can get.  */
188                 s->arglen = 1;
189                 s->response[0] = 4;
190             } else {
191                 /* All other commands return status.  */
192                 uint32_t cardstatus;
193                 uint16_t status;
194                 /* CMD13 returns a 2-byte statuse work. Other commands
195                    only return the first byte.  */
196                 s->arglen = (s->cmd == 13) ? 2 : 1;
197 
198                 /* handle R1b */
199                 if (s->cmd == 28 || s->cmd == 29 || s->cmd == 38) {
200                     s->stopping = 1;
201                 }
202 
203                 cardstatus = ldl_be_p(longresp);
204                 status = 0;
205                 if (((cardstatus >> 9) & 0xf) < 4)
206                     status |= SSI_SDR_IDLE;
207                 if (cardstatus & ERASE_RESET)
208                     status |= SSI_SDR_ERASE_RESET;
209                 if (cardstatus & ILLEGAL_COMMAND)
210                     status |= SSI_SDR_ILLEGAL_COMMAND;
211                 if (cardstatus & COM_CRC_ERROR)
212                     status |= SSI_SDR_COM_CRC_ERROR;
213                 if (cardstatus & ERASE_SEQ_ERROR)
214                     status |= SSI_SDR_ERASE_SEQ_ERROR;
215                 if (cardstatus & ADDRESS_ERROR)
216                     status |= SSI_SDR_ADDRESS_ERROR;
217                 if (cardstatus & CARD_IS_LOCKED)
218                     status |= SSI_SDR_LOCKED;
219                 if (cardstatus & (LOCK_UNLOCK_FAILED | WP_ERASE_SKIP))
220                     status |= SSI_SDR_WP_ERASE;
221                 if (cardstatus & SD_ERROR)
222                     status |= SSI_SDR_ERROR;
223                 if (cardstatus & CC_ERROR)
224                     status |= SSI_SDR_CC_ERROR;
225                 if (cardstatus & CARD_ECC_FAILED)
226                     status |= SSI_SDR_ECC_FAILED;
227                 if (cardstatus & WP_VIOLATION)
228                     status |= SSI_SDR_WP_VIOLATION;
229                 if (cardstatus & ERASE_PARAM)
230                     status |= SSI_SDR_ERASE_PARAM;
231                 if (cardstatus & (OUT_OF_RANGE | CID_CSD_OVERWRITE))
232                     status |= SSI_SDR_OUT_OF_RANGE;
233                 /* ??? Don't know what Parameter Error really means, so
234                    assume it's set if the second byte is nonzero.  */
235                 if (status & 0xff)
236                     status |= SSI_SDR_PARAMETER_ERROR;
237                 s->response[0] = status >> 8;
238                 s->response[1] = status;
239                 DPRINTF("Card status 0x%02x\n", status);
240             }
241             s->mode = SSI_SD_PREP_RESP;
242             s->response_pos = 0;
243         } else {
244             s->cmdarg[s->arglen++] = val;
245         }
246         return SSI_DUMMY;
247     case SSI_SD_PREP_RESP:
248         DPRINTF("Prepare card response (Ncr)\n");
249         s->mode = SSI_SD_RESPONSE;
250         return SSI_DUMMY;
251     case SSI_SD_RESPONSE:
252         if (s->response_pos < s->arglen) {
253             DPRINTF("Response 0x%02x\n", s->response[s->response_pos]);
254             return s->response[s->response_pos++];
255         }
256         if (s->stopping) {
257             s->stopping = 0;
258             s->mode = SSI_SD_CMD;
259             return SSI_DUMMY;
260         }
261         if (sdbus_data_ready(&s->sdbus)) {
262             DPRINTF("Data read\n");
263             s->mode = SSI_SD_DATA_START;
264         } else {
265             DPRINTF("End of command\n");
266             s->mode = SSI_SD_CMD;
267         }
268         return SSI_DUMMY;
269     case SSI_SD_PREP_DATA:
270         DPRINTF("Prepare data block (Nac)\n");
271         s->mode = SSI_SD_DATA_START;
272         return SSI_DUMMY;
273     case SSI_SD_DATA_START:
274         DPRINTF("Start read block\n");
275         s->mode = SSI_SD_DATA_READ;
276         s->response_pos = 0;
277         return SSI_TOKEN_SINGLE;
278     case SSI_SD_DATA_READ:
279         val = sdbus_read_byte(&s->sdbus);
280         s->read_bytes++;
281         s->crc16 = crc_ccitt_false(s->crc16, (uint8_t *)&val, 1);
282         if (!sdbus_data_ready(&s->sdbus) || s->read_bytes == 512) {
283             DPRINTF("Data read end\n");
284             s->mode = SSI_SD_DATA_CRC16;
285         }
286         return val;
287     case SSI_SD_DATA_CRC16:
288         val = (s->crc16 & 0xff00) >> 8;
289         s->crc16 <<= 8;
290         s->response_pos++;
291         if (s->response_pos == 2) {
292             DPRINTF("CRC16 read end\n");
293             if (s->read_bytes == 512 && s->cmd != 17) {
294                 s->mode = SSI_SD_PREP_DATA;
295             } else {
296                 s->mode = SSI_SD_CMD;
297             }
298             s->read_bytes = 0;
299             s->response_pos = 0;
300         }
301         return val;
302     case SSI_SD_DATA_WRITE:
303         sdbus_write_byte(&s->sdbus, val);
304         s->write_bytes++;
305         if (!sdbus_receive_ready(&s->sdbus) || s->write_bytes == 512) {
306             DPRINTF("Data write end\n");
307             s->mode = SSI_SD_SKIP_CRC16;
308             s->response_pos = 0;
309         }
310         return val;
311     case SSI_SD_SKIP_CRC16:
312         /* we don't verify the crc16 */
313         s->response_pos++;
314         if (s->response_pos == 2) {
315             DPRINTF("CRC16 receive end\n");
316             s->mode = SSI_SD_RESPONSE;
317             s->write_bytes = 0;
318             s->arglen = 1;
319             s->response[0] = DATA_RESPONSE_ACCEPTED;
320             s->response_pos = 0;
321         }
322         return SSI_DUMMY;
323     }
324     /* Should never happen.  */
325     return SSI_DUMMY;
326 }
327 
328 static int ssi_sd_post_load(void *opaque, int version_id)
329 {
330     ssi_sd_state *s = (ssi_sd_state *)opaque;
331 
332     if (s->mode > SSI_SD_SKIP_CRC16) {
333         return -EINVAL;
334     }
335     if (s->mode == SSI_SD_CMDARG &&
336         (s->arglen < 0 || s->arglen >= ARRAY_SIZE(s->cmdarg))) {
337         return -EINVAL;
338     }
339     if (s->mode == SSI_SD_RESPONSE &&
340         (s->response_pos < 0 || s->response_pos >= ARRAY_SIZE(s->response) ||
341         (!s->stopping && s->arglen > ARRAY_SIZE(s->response)))) {
342         return -EINVAL;
343     }
344 
345     return 0;
346 }
347 
348 static const VMStateDescription vmstate_ssi_sd = {
349     .name = "ssi_sd",
350     .version_id = 7,
351     .minimum_version_id = 7,
352     .post_load = ssi_sd_post_load,
353     .fields = (const VMStateField []) {
354         VMSTATE_UINT32(mode, ssi_sd_state),
355         VMSTATE_INT32(cmd, ssi_sd_state),
356         VMSTATE_UINT8_ARRAY(cmdarg, ssi_sd_state, 4),
357         VMSTATE_UINT8_ARRAY(response, ssi_sd_state, 5),
358         VMSTATE_UINT16(crc16, ssi_sd_state),
359         VMSTATE_INT32(read_bytes, ssi_sd_state),
360         VMSTATE_INT32(write_bytes, ssi_sd_state),
361         VMSTATE_INT32(arglen, ssi_sd_state),
362         VMSTATE_INT32(response_pos, ssi_sd_state),
363         VMSTATE_INT32(stopping, ssi_sd_state),
364         VMSTATE_SSI_PERIPHERAL(ssidev, ssi_sd_state),
365         VMSTATE_END_OF_LIST()
366     }
367 };
368 
369 static void ssi_sd_realize(SSIPeripheral *d, Error **errp)
370 {
371     ssi_sd_state *s = SSI_SD(d);
372 
373     qbus_init(&s->sdbus, sizeof(s->sdbus), TYPE_SD_BUS, DEVICE(d), "sd-bus");
374 }
375 
376 static void ssi_sd_reset(DeviceState *dev)
377 {
378     ssi_sd_state *s = SSI_SD(dev);
379 
380     s->mode = SSI_SD_CMD;
381     s->cmd = 0;
382     memset(s->cmdarg, 0, sizeof(s->cmdarg));
383     memset(s->response, 0, sizeof(s->response));
384     s->crc16 = 0;
385     s->read_bytes = 0;
386     s->write_bytes = 0;
387     s->arglen = 0;
388     s->response_pos = 0;
389     s->stopping = 0;
390 }
391 
392 static void ssi_sd_class_init(ObjectClass *klass, void *data)
393 {
394     DeviceClass *dc = DEVICE_CLASS(klass);
395     SSIPeripheralClass *k = SSI_PERIPHERAL_CLASS(klass);
396 
397     k->realize = ssi_sd_realize;
398     k->transfer = ssi_sd_transfer;
399     k->cs_polarity = SSI_CS_LOW;
400     dc->vmsd = &vmstate_ssi_sd;
401     device_class_set_legacy_reset(dc, ssi_sd_reset);
402     /* Reason: GPIO chip-select line should be wired up */
403     dc->user_creatable = false;
404 }
405 
406 static const TypeInfo ssi_sd_types[] = {
407     {
408         .name           = TYPE_SSI_SD,
409         .parent         = TYPE_SSI_PERIPHERAL,
410         .instance_size  = sizeof(ssi_sd_state),
411         .class_init     = ssi_sd_class_init,
412     },
413 };
414 
415 DEFINE_TYPES(ssi_sd_types)
416