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 "system/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 /* multiple block write */ 74 #define SSI_TOKEN_MULTI_WRITE 0xfc 75 /* terminate multiple block write */ 76 #define SSI_TOKEN_STOP_TRAN 0xfd 77 /* single block read/write, multiple block read */ 78 #define SSI_TOKEN_SINGLE 0xfe 79 80 /* dummy value - don't care */ 81 #define SSI_DUMMY 0xff 82 83 /* data accepted */ 84 #define DATA_RESPONSE_ACCEPTED 0x05 85 86 static uint32_t ssi_sd_transfer(SSIPeripheral *dev, uint32_t val) 87 { 88 ssi_sd_state *s = SSI_SD(dev); 89 SDRequest request; 90 uint8_t longresp[5]; 91 92 /* 93 * Special case: allow CMD12 (STOP TRANSMISSION) while reading data. 94 * 95 * See "Physical Layer Specification Version 8.00" chapter 7.5.2.2, 96 * to avoid conflict between CMD12 response and next data block, 97 * timing of CMD12 should be controlled as follows: 98 * 99 * - CMD12 issued at the timing that end bit of CMD12 and end bit of 100 * data block is overlapped 101 * - CMD12 issued after one clock cycle after host receives a token 102 * (either Start Block token or Data Error token) 103 * 104 * We need to catch CMD12 in all of the data read states. 105 */ 106 if (s->mode >= SSI_SD_PREP_DATA && s->mode <= SSI_SD_DATA_CRC16) { 107 if (val == 0x4c) { 108 s->mode = SSI_SD_CMD; 109 /* There must be at least one byte delay before the card responds */ 110 s->stopping = 1; 111 } 112 } 113 114 switch (s->mode) { 115 case SSI_SD_CMD: 116 switch (val) { 117 case SSI_DUMMY: 118 DPRINTF("NULL command\n"); 119 return SSI_DUMMY; 120 break; 121 case SSI_TOKEN_SINGLE: 122 case SSI_TOKEN_MULTI_WRITE: 123 DPRINTF("Start write block\n"); 124 s->mode = SSI_SD_DATA_WRITE; 125 return SSI_DUMMY; 126 case SSI_TOKEN_STOP_TRAN: 127 DPRINTF("Stop multiple write\n"); 128 129 /* manually issue cmd12 to stop the transfer */ 130 request.cmd = 12; 131 request.arg = 0; 132 s->arglen = sdbus_do_command(&s->sdbus, &request, 133 longresp, sizeof(longresp)); 134 if (s->arglen == 0) { 135 s->arglen = 1; 136 /* a zero value indicates the card is busy */ 137 s->response[0] = 0; 138 DPRINTF("SD card busy\n"); 139 } else { 140 s->arglen = 1; 141 /* a non-zero value indicates the card is ready */ 142 s->response[0] = SSI_DUMMY; 143 } 144 145 return SSI_DUMMY; 146 } 147 148 s->cmd = val & 0x3f; 149 s->mode = SSI_SD_CMDARG; 150 s->arglen = 0; 151 return SSI_DUMMY; 152 case SSI_SD_CMDARG: 153 if (s->arglen == 4) { 154 /* FIXME: Check CRC. */ 155 request.cmd = s->cmd; 156 request.arg = ldl_be_p(s->cmdarg); 157 s->arglen = sdbus_do_command(&s->sdbus, &request, 158 longresp, sizeof(longresp)); 159 DPRINTF("CMD%d arg 0x%08x = %d\n", s->cmd, request.arg, s->arglen); 160 assert(s->arglen > 0); 161 /* CMD13 returns a 2-byte statuse work. Other commands 162 only return the first byte. */ 163 s->arglen = (s->cmd == 13) ? 2 : 1; 164 memcpy(s->response, longresp, s->arglen); 165 166 /* handle R1b (busy signal) */ 167 if (s->cmd == 28 || s->cmd == 29 || s->cmd == 38) { 168 s->stopping = 1; 169 } 170 s->mode = SSI_SD_PREP_RESP; 171 s->response_pos = 0; 172 } else { 173 s->cmdarg[s->arglen++] = val; 174 } 175 return SSI_DUMMY; 176 case SSI_SD_PREP_RESP: 177 DPRINTF("Prepare card response (Ncr)\n"); 178 s->mode = SSI_SD_RESPONSE; 179 return SSI_DUMMY; 180 case SSI_SD_RESPONSE: 181 if (s->response_pos < s->arglen) { 182 DPRINTF("Response 0x%02x\n", s->response[s->response_pos]); 183 return s->response[s->response_pos++]; 184 } 185 if (s->stopping) { 186 s->stopping = 0; 187 s->mode = SSI_SD_CMD; 188 return SSI_DUMMY; 189 } 190 if (sdbus_data_ready(&s->sdbus)) { 191 DPRINTF("Data read\n"); 192 s->mode = SSI_SD_DATA_START; 193 } else { 194 DPRINTF("End of command\n"); 195 s->mode = SSI_SD_CMD; 196 } 197 return SSI_DUMMY; 198 case SSI_SD_PREP_DATA: 199 DPRINTF("Prepare data block (Nac)\n"); 200 s->mode = SSI_SD_DATA_START; 201 return SSI_DUMMY; 202 case SSI_SD_DATA_START: 203 DPRINTF("Start read block\n"); 204 s->mode = SSI_SD_DATA_READ; 205 s->response_pos = 0; 206 return SSI_TOKEN_SINGLE; 207 case SSI_SD_DATA_READ: 208 val = sdbus_read_byte(&s->sdbus); 209 s->read_bytes++; 210 s->crc16 = crc_ccitt_false(s->crc16, (uint8_t *)&val, 1); 211 if (!sdbus_data_ready(&s->sdbus) || s->read_bytes == 512) { 212 DPRINTF("Data read end\n"); 213 s->mode = SSI_SD_DATA_CRC16; 214 } 215 return val; 216 case SSI_SD_DATA_CRC16: 217 val = (s->crc16 & 0xff00) >> 8; 218 s->crc16 <<= 8; 219 s->response_pos++; 220 if (s->response_pos == 2) { 221 DPRINTF("CRC16 read end\n"); 222 if (s->read_bytes == 512 && s->cmd != 17) { 223 s->mode = SSI_SD_PREP_DATA; 224 } else { 225 s->mode = SSI_SD_CMD; 226 } 227 s->read_bytes = 0; 228 s->response_pos = 0; 229 } 230 return val; 231 case SSI_SD_DATA_WRITE: 232 sdbus_write_byte(&s->sdbus, val); 233 s->write_bytes++; 234 if (!sdbus_receive_ready(&s->sdbus) || s->write_bytes == 512) { 235 DPRINTF("Data write end\n"); 236 s->mode = SSI_SD_SKIP_CRC16; 237 s->response_pos = 0; 238 } 239 return val; 240 case SSI_SD_SKIP_CRC16: 241 /* we don't verify the crc16 */ 242 s->response_pos++; 243 if (s->response_pos == 2) { 244 DPRINTF("CRC16 receive end\n"); 245 s->mode = SSI_SD_RESPONSE; 246 s->write_bytes = 0; 247 s->arglen = 1; 248 s->response[0] = DATA_RESPONSE_ACCEPTED; 249 s->response_pos = 0; 250 } 251 return SSI_DUMMY; 252 } 253 /* Should never happen. */ 254 return SSI_DUMMY; 255 } 256 257 static int ssi_sd_post_load(void *opaque, int version_id) 258 { 259 ssi_sd_state *s = (ssi_sd_state *)opaque; 260 261 if (s->mode > SSI_SD_SKIP_CRC16) { 262 return -EINVAL; 263 } 264 if (s->mode == SSI_SD_CMDARG && 265 (s->arglen >= ARRAY_SIZE(s->cmdarg))) { 266 return -EINVAL; 267 } 268 if (s->mode == SSI_SD_RESPONSE && 269 (s->response_pos < 0 || s->response_pos >= ARRAY_SIZE(s->response) || 270 (!s->stopping && s->arglen > ARRAY_SIZE(s->response)))) { 271 return -EINVAL; 272 } 273 274 return 0; 275 } 276 277 static const VMStateDescription vmstate_ssi_sd = { 278 .name = "ssi_sd", 279 .version_id = 7, 280 .minimum_version_id = 7, 281 .post_load = ssi_sd_post_load, 282 .fields = (const VMStateField []) { 283 VMSTATE_UINT32(mode, ssi_sd_state), 284 VMSTATE_INT32(cmd, ssi_sd_state), 285 VMSTATE_UINT8_ARRAY(cmdarg, ssi_sd_state, 4), 286 VMSTATE_UINT8_ARRAY(response, ssi_sd_state, 5), 287 VMSTATE_UINT16(crc16, ssi_sd_state), 288 VMSTATE_INT32(read_bytes, ssi_sd_state), 289 VMSTATE_INT32(write_bytes, ssi_sd_state), 290 VMSTATE_INT32(arglen, ssi_sd_state), 291 VMSTATE_INT32(response_pos, ssi_sd_state), 292 VMSTATE_INT32(stopping, ssi_sd_state), 293 VMSTATE_SSI_PERIPHERAL(ssidev, ssi_sd_state), 294 VMSTATE_END_OF_LIST() 295 } 296 }; 297 298 static void ssi_sd_realize(SSIPeripheral *d, Error **errp) 299 { 300 ssi_sd_state *s = SSI_SD(d); 301 302 qbus_init(&s->sdbus, sizeof(s->sdbus), TYPE_SD_BUS, DEVICE(d), "sd-bus"); 303 } 304 305 static void ssi_sd_reset(DeviceState *dev) 306 { 307 ssi_sd_state *s = SSI_SD(dev); 308 309 s->mode = SSI_SD_CMD; 310 s->cmd = 0; 311 memset(s->cmdarg, 0, sizeof(s->cmdarg)); 312 memset(s->response, 0, sizeof(s->response)); 313 s->crc16 = 0; 314 s->read_bytes = 0; 315 s->write_bytes = 0; 316 s->arglen = 0; 317 s->response_pos = 0; 318 s->stopping = 0; 319 } 320 321 static void ssi_sd_class_init(ObjectClass *klass, const void *data) 322 { 323 DeviceClass *dc = DEVICE_CLASS(klass); 324 SSIPeripheralClass *k = SSI_PERIPHERAL_CLASS(klass); 325 326 k->realize = ssi_sd_realize; 327 k->transfer = ssi_sd_transfer; 328 k->cs_polarity = SSI_CS_LOW; 329 dc->vmsd = &vmstate_ssi_sd; 330 device_class_set_legacy_reset(dc, ssi_sd_reset); 331 /* Reason: GPIO chip-select line should be wired up */ 332 dc->user_creatable = false; 333 } 334 335 static const TypeInfo ssi_sd_types[] = { 336 { 337 .name = TYPE_SSI_SD, 338 .parent = TYPE_SSI_PERIPHERAL, 339 .instance_size = sizeof(ssi_sd_state), 340 .class_init = ssi_sd_class_init, 341 }, 342 }; 343 344 DEFINE_TYPES(ssi_sd_types) 345