1 /* 2 * generic mmc spi driver 3 * 4 * Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw> 5 * Licensed under the GPL-2 or later. 6 */ 7 #include <common.h> 8 #include <malloc.h> 9 #include <part.h> 10 #include <mmc.h> 11 #include <spi.h> 12 #include <crc.h> 13 #include <linux/crc7.h> 14 #include <linux/byteorder/swab.h> 15 16 /* MMC/SD in SPI mode reports R1 status always */ 17 #define R1_SPI_IDLE (1 << 0) 18 #define R1_SPI_ERASE_RESET (1 << 1) 19 #define R1_SPI_ILLEGAL_COMMAND (1 << 2) 20 #define R1_SPI_COM_CRC (1 << 3) 21 #define R1_SPI_ERASE_SEQ (1 << 4) 22 #define R1_SPI_ADDRESS (1 << 5) 23 #define R1_SPI_PARAMETER (1 << 6) 24 /* R1 bit 7 is always zero, reuse this bit for error */ 25 #define R1_SPI_ERROR (1 << 7) 26 27 /* Response tokens used to ack each block written: */ 28 #define SPI_MMC_RESPONSE_CODE(x) ((x) & 0x1f) 29 #define SPI_RESPONSE_ACCEPTED ((2 << 1)|1) 30 #define SPI_RESPONSE_CRC_ERR ((5 << 1)|1) 31 #define SPI_RESPONSE_WRITE_ERR ((6 << 1)|1) 32 33 /* Read and write blocks start with these tokens and end with crc; 34 * on error, read tokens act like a subset of R2_SPI_* values. 35 */ 36 #define SPI_TOKEN_SINGLE 0xfe /* single block r/w, multiblock read */ 37 #define SPI_TOKEN_MULTI_WRITE 0xfc /* multiblock write */ 38 #define SPI_TOKEN_STOP_TRAN 0xfd /* terminate multiblock write */ 39 40 /* MMC SPI commands start with a start bit "0" and a transmit bit "1" */ 41 #define MMC_SPI_CMD(x) (0x40 | (x & 0x3f)) 42 43 /* bus capability */ 44 #define MMC_SPI_VOLTAGE (MMC_VDD_32_33 | MMC_VDD_33_34) 45 #define MMC_SPI_MIN_CLOCK 400000 /* 400KHz to meet MMC spec */ 46 47 /* timeout value */ 48 #define CTOUT 8 49 #define RTOUT 3000000 /* 1 sec */ 50 #define WTOUT 3000000 /* 1 sec */ 51 52 static uint mmc_spi_sendcmd(struct mmc *mmc, ushort cmdidx, u32 cmdarg) 53 { 54 struct spi_slave *spi = mmc->priv; 55 u8 cmdo[7]; 56 u8 r1; 57 int i; 58 cmdo[0] = 0xff; 59 cmdo[1] = MMC_SPI_CMD(cmdidx); 60 cmdo[2] = cmdarg >> 24; 61 cmdo[3] = cmdarg >> 16; 62 cmdo[4] = cmdarg >> 8; 63 cmdo[5] = cmdarg; 64 cmdo[6] = (crc7(0, &cmdo[1], 5) << 1) | 0x01; 65 spi_xfer(spi, sizeof(cmdo) * 8, cmdo, NULL, 0); 66 for (i = 0; i < CTOUT; i++) { 67 spi_xfer(spi, 1 * 8, NULL, &r1, 0); 68 if (i && (r1 & 0x80) == 0) /* r1 response */ 69 break; 70 } 71 debug("%s:cmd%d resp%d %x\n", __func__, cmdidx, i, r1); 72 return r1; 73 } 74 75 static uint mmc_spi_readdata(struct mmc *mmc, void *xbuf, 76 u32 bcnt, u32 bsize) 77 { 78 struct spi_slave *spi = mmc->priv; 79 u8 *buf = xbuf; 80 u8 r1; 81 u16 crc; 82 int i; 83 while (bcnt--) { 84 for (i = 0; i < RTOUT; i++) { 85 spi_xfer(spi, 1 * 8, NULL, &r1, 0); 86 if (r1 != 0xff) /* data token */ 87 break; 88 } 89 debug("%s:tok%d %x\n", __func__, i, r1); 90 if (r1 == SPI_TOKEN_SINGLE) { 91 spi_xfer(spi, bsize * 8, NULL, buf, 0); 92 spi_xfer(spi, 2 * 8, NULL, &crc, 0); 93 #ifdef CONFIG_MMC_SPI_CRC_ON 94 if (swab16(cyg_crc16(buf, bsize)) != crc) { 95 debug("%s: CRC error\n", mmc->name); 96 r1 = R1_SPI_COM_CRC; 97 break; 98 } 99 #endif 100 r1 = 0; 101 } else { 102 r1 = R1_SPI_ERROR; 103 break; 104 } 105 buf += bsize; 106 } 107 return r1; 108 } 109 110 static uint mmc_spi_writedata(struct mmc *mmc, const void *xbuf, 111 u32 bcnt, u32 bsize, int multi) 112 { 113 struct spi_slave *spi = mmc->priv; 114 const u8 *buf = xbuf; 115 u8 r1; 116 u16 crc; 117 u8 tok[2]; 118 int i; 119 tok[0] = 0xff; 120 tok[1] = multi ? SPI_TOKEN_MULTI_WRITE : SPI_TOKEN_SINGLE; 121 while (bcnt--) { 122 #ifdef CONFIG_MMC_SPI_CRC_ON 123 crc = swab16(cyg_crc16((u8 *)buf, bsize)); 124 #endif 125 spi_xfer(spi, 2 * 8, tok, NULL, 0); 126 spi_xfer(spi, bsize * 8, buf, NULL, 0); 127 spi_xfer(spi, 2 * 8, &crc, NULL, 0); 128 for (i = 0; i < CTOUT; i++) { 129 spi_xfer(spi, 1 * 8, NULL, &r1, 0); 130 if ((r1 & 0x10) == 0) /* response token */ 131 break; 132 } 133 debug("%s:tok%d %x\n", __func__, i, r1); 134 if (SPI_MMC_RESPONSE_CODE(r1) == SPI_RESPONSE_ACCEPTED) { 135 for (i = 0; i < WTOUT; i++) { /* wait busy */ 136 spi_xfer(spi, 1 * 8, NULL, &r1, 0); 137 if (i && r1 == 0xff) { 138 r1 = 0; 139 break; 140 } 141 } 142 if (i == WTOUT) { 143 debug("%s:wtout %x\n", __func__, r1); 144 r1 = R1_SPI_ERROR; 145 break; 146 } 147 } else { 148 debug("%s: err %x\n", __func__, r1); 149 r1 = R1_SPI_COM_CRC; 150 break; 151 } 152 buf += bsize; 153 } 154 if (multi && bcnt == -1) { /* stop multi write */ 155 tok[1] = SPI_TOKEN_STOP_TRAN; 156 spi_xfer(spi, 2 * 8, tok, NULL, 0); 157 for (i = 0; i < WTOUT; i++) { /* wait busy */ 158 spi_xfer(spi, 1 * 8, NULL, &r1, 0); 159 if (i && r1 == 0xff) { 160 r1 = 0; 161 break; 162 } 163 } 164 if (i == WTOUT) { 165 debug("%s:wstop %x\n", __func__, r1); 166 r1 = R1_SPI_ERROR; 167 } 168 } 169 return r1; 170 } 171 172 static int mmc_spi_request(struct mmc *mmc, struct mmc_cmd *cmd, 173 struct mmc_data *data) 174 { 175 struct spi_slave *spi = mmc->priv; 176 u8 r1; 177 int i; 178 int ret = 0; 179 debug("%s:cmd%d %x %x\n", __func__, 180 cmd->cmdidx, cmd->resp_type, cmd->cmdarg); 181 spi_claim_bus(spi); 182 spi_cs_activate(spi); 183 r1 = mmc_spi_sendcmd(mmc, cmd->cmdidx, cmd->cmdarg); 184 if (r1 == 0xff) { /* no response */ 185 ret = NO_CARD_ERR; 186 goto done; 187 } else if (r1 & R1_SPI_COM_CRC) { 188 ret = COMM_ERR; 189 goto done; 190 } else if (r1 & ~R1_SPI_IDLE) { /* other errors */ 191 ret = TIMEOUT; 192 goto done; 193 } else if (cmd->resp_type == MMC_RSP_R2) { 194 r1 = mmc_spi_readdata(mmc, cmd->response, 1, 16); 195 for (i = 0; i < 4; i++) 196 cmd->response[i] = swab32(cmd->response[i]); 197 debug("r128 %x %x %x %x\n", cmd->response[0], cmd->response[1], 198 cmd->response[2], cmd->response[3]); 199 } else if (!data) { 200 switch (cmd->cmdidx) { 201 case SD_CMD_APP_SEND_OP_COND: 202 case MMC_CMD_SEND_OP_COND: 203 cmd->response[0] = (r1 & R1_SPI_IDLE) ? 0 : OCR_BUSY; 204 break; 205 case SD_CMD_SEND_IF_COND: 206 case MMC_CMD_SPI_READ_OCR: 207 spi_xfer(spi, 4 * 8, NULL, cmd->response, 0); 208 cmd->response[0] = swab32(cmd->response[0]); 209 debug("r32 %x\n", cmd->response[0]); 210 break; 211 case MMC_CMD_SEND_STATUS: 212 spi_xfer(spi, 1 * 8, NULL, cmd->response, 0); 213 cmd->response[0] = (cmd->response[0] & 0xff) ? 214 MMC_STATUS_ERROR : MMC_STATUS_RDY_FOR_DATA; 215 break; 216 } 217 } else { 218 debug("%s:data %x %x %x\n", __func__, 219 data->flags, data->blocks, data->blocksize); 220 if (data->flags == MMC_DATA_READ) 221 r1 = mmc_spi_readdata(mmc, data->dest, 222 data->blocks, data->blocksize); 223 else if (data->flags == MMC_DATA_WRITE) 224 r1 = mmc_spi_writedata(mmc, data->src, 225 data->blocks, data->blocksize, 226 (cmd->cmdidx == MMC_CMD_WRITE_MULTIPLE_BLOCK)); 227 if (r1 & R1_SPI_COM_CRC) 228 ret = COMM_ERR; 229 else if (r1) /* other errors */ 230 ret = TIMEOUT; 231 } 232 done: 233 spi_cs_deactivate(spi); 234 spi_release_bus(spi); 235 return ret; 236 } 237 238 static void mmc_spi_set_ios(struct mmc *mmc) 239 { 240 struct spi_slave *spi = mmc->priv; 241 debug("%s: clock %u\n", __func__, mmc->clock); 242 if (mmc->clock) 243 spi_set_speed(spi, mmc->clock); 244 } 245 246 static int mmc_spi_init_p(struct mmc *mmc) 247 { 248 struct spi_slave *spi = mmc->priv; 249 mmc->clock = 0; 250 spi_set_speed(spi, MMC_SPI_MIN_CLOCK); 251 spi_claim_bus(spi); 252 /* cs deactivated for 100+ clock */ 253 spi_xfer(spi, 18 * 8, NULL, NULL, 0); 254 spi_release_bus(spi); 255 return 0; 256 } 257 258 struct mmc *mmc_spi_init(uint bus, uint cs, uint speed, uint mode) 259 { 260 struct mmc *mmc; 261 262 mmc = malloc(sizeof(*mmc)); 263 if (!mmc) 264 return NULL; 265 memset(mmc, 0, sizeof(*mmc)); 266 mmc->priv = spi_setup_slave(bus, cs, speed, mode); 267 if (!mmc->priv) { 268 free(mmc); 269 return NULL; 270 } 271 sprintf(mmc->name, "MMC_SPI"); 272 mmc->send_cmd = mmc_spi_request; 273 mmc->set_ios = mmc_spi_set_ios; 274 mmc->init = mmc_spi_init_p; 275 mmc->getcd = NULL; 276 mmc->getwp = NULL; 277 mmc->host_caps = MMC_MODE_SPI; 278 279 mmc->voltages = MMC_SPI_VOLTAGE; 280 mmc->f_max = speed; 281 mmc->f_min = MMC_SPI_MIN_CLOCK; 282 mmc->block_dev.part_type = PART_TYPE_DOS; 283 284 mmc_register(mmc); 285 286 return mmc; 287 } 288