hw/ssi-sd.c

   1 /*
   2  * SSI to SD card adapter.
   3  *
   4  * Copyright (c) 2007 CodeSourcery.
   5  * Written by Paul Brook
   6  *
   7  * This code is licenced under the GPL.
   8  */
   9
  10 #include "hw.h"
  11 #include "sd.h"
  12
  13 //#define DEBUG_SSI_SD 1
  14
  15 #ifdef DEBUG_SSI_SD
  16 #define DPRINTF(fmt, args...) \
  17 do { printf("ssi_sd: " fmt , ##args); } while (0)
  18 #define BADF(fmt, args...) \
  19 do { fprintf(stderr, "ssi_sd: error: " fmt , ##args); exit(1);} while (0)
  20 #else
  21 #define DPRINTF(fmt, args...) do {} while(0)
  22 #define BADF(fmt, args...) \
  23 do { fprintf(stderr, "ssi_sd: error: " fmt , ##args);} while (0)
  24 #endif
  25
  26 typedef enum {
  27     SSI_SD_CMD,
  28     SSI_SD_CMDARG,
  29     SSI_SD_RESPONSE,
  30     SSI_SD_DATA_START,
  31     SSI_SD_DATA_READ,
  32 } ssi_sd_mode;
  33
  34 typedef struct {
  35     ssi_sd_mode mode;
  36     int cmd;
  37     uint8_t cmdarg[4];
  38     uint8_t response[5];
  39     int arglen;
  40     int response_pos;
  41     int stopping;
  42     SDState *sd;
  43 } ssi_sd_state;
  44
  45 /* State word bits.  */
  46 #define SSI_SDR_LOCKED          0x0001
  47 #define SSI_SDR_WP_ERASE        0x0002
  48 #define SSI_SDR_ERROR           0x0004
  49 #define SSI_SDR_CC_ERROR        0x0008
  50 #define SSI_SDR_ECC_FAILED      0x0010
  51 #define SSI_SDR_WP_VIOLATION    0x0020
  52 #define SSI_SDR_ERASE_PARAM     0x0040
  53 #define SSI_SDR_OUT_OF_RANGE    0x0080
  54 #define SSI_SDR_IDLE            0x0100
  55 #define SSI_SDR_ERASE_RESET     0x0200
  56 #define SSI_SDR_ILLEGAL_COMMAND 0x0400
  57 #define SSI_SDR_COM_CRC_ERROR   0x0800
  58 #define SSI_SDR_ERASE_SEQ_ERROR 0x1000
  59 #define SSI_SDR_ADDRESS_ERROR   0x2000
  60 #define SSI_SDR_PARAMETER_ERROR 0x4000
  61
  62 int ssi_sd_xfer(void *opaque, int val)
  63 {
  64     ssi_sd_state *s = (ssi_sd_state *)opaque;
  65
  66     /* Special case: allow CMD12 (STOP TRANSMISSION) while reading data.  */
  67     if (s->mode == SSI_SD_DATA_READ && val == 0x4d) {
  68         s->mode = SSI_SD_CMD;
  69         /* There must be at least one byte delay before the card responds.  */
  70         s->stopping = 1;
  71     }
  72
  73     switch (s->mode) {
  74     case SSI_SD_CMD:
  75         if (val == 0xff) {
  76             DPRINTF("NULL command\n");
  77             return 0xff;
  78         }
  79         s->cmd = val & 0x3f;
  80         s->mode = SSI_SD_CMDARG;
  81         s->arglen = 0;
  82         return 0xff;
  83     case SSI_SD_CMDARG:
  84         if (s->arglen == 4) {
  85             struct sd_request_s request;
  86             uint8_t longresp[16];
  87             /* FIXME: Check CRC.  */
  88             request.cmd = s->cmd;
  89             request.arg = (s->cmdarg[0] << 24) | (s->cmdarg[1] << 16)
  90                            | (s->cmdarg[2] << 8) | s->cmdarg[3];
  91             DPRINTF("CMD%d arg 0x%08x\n", s->cmd, request.arg);
  92             s->arglen = sd_do_command(s->sd, &request, longresp);
  93             if (s->arglen <= 0) {
  94                 s->arglen = 1;
  95                 s->response[0] = 4;
  96                 DPRINTF("SD command failed\n");
  97             } else if (s->cmd == 58) {
  98                 /* CMD58 returns R3 response (OCR)  */
  99                 DPRINTF("Returned OCR\n");
 100                 s->arglen = 5;
 101                 s->response[0] = 1;
 102                 memcpy(&s->response[1], longresp, 4);
 103             } else if (s->arglen != 4) {
 104                 BADF("Unexpected response to cmd %d\n", s->cmd);
 105                 /* Illegal command is about as near as we can get.  */
 106                 s->arglen = 1;
 107                 s->response[0] = 4;
 108             } else {
 109                 /* All other commands return status.  */
 110                 uint32_t cardstatus;
 111                 uint16_t status;
 112                 /* CMD13 returns a 2-byte statuse work. Other commands
 113                    only return the first byte.  */
 114                 s->arglen = (s->cmd == 13) ? 2 : 1;
 115                 cardstatus = (longresp[0] << 24) | (longresp[1] << 16)
 116                              | (longresp[2] << 8) | longresp[3];
 117                 status = 0;
 118                 if (((cardstatus >> 9) & 0xf) < 4)
 119                     status |= SSI_SDR_IDLE;
 120                 if (cardstatus & ERASE_RESET)
 121                     status |= SSI_SDR_ERASE_RESET;
 122                 if (cardstatus & ILLEGAL_COMMAND)
 123                     status |= SSI_SDR_ILLEGAL_COMMAND;
 124                 if (cardstatus & COM_CRC_ERROR)
 125                     status |= SSI_SDR_COM_CRC_ERROR;
 126                 if (cardstatus & ERASE_SEQ_ERROR)
 127                     status |= SSI_SDR_ERASE_SEQ_ERROR;
 128                 if (cardstatus & ADDRESS_ERROR)
 129                     status |= SSI_SDR_ADDRESS_ERROR;
 130                 if (cardstatus & CARD_IS_LOCKED)
 131                     status |= SSI_SDR_LOCKED;
 132                 if (cardstatus & (LOCK_UNLOCK_FAILED | WP_ERASE_SKIP))
 133                     status |= SSI_SDR_WP_ERASE;
 134                 if (cardstatus & SD_ERROR)
 135                     status |= SSI_SDR_ERROR;
 136                 if (cardstatus & CC_ERROR)
 137                     status |= SSI_SDR_CC_ERROR;
 138                 if (cardstatus & CARD_ECC_FAILED)
 139                     status |= SSI_SDR_ECC_FAILED;
 140                 if (cardstatus & WP_VIOLATION)
 141                     status |= SSI_SDR_WP_VIOLATION;
 142                 if (cardstatus & ERASE_PARAM)
 143                     status |= SSI_SDR_ERASE_PARAM;
 144                 if (cardstatus & (OUT_OF_RANGE | CID_CSD_OVERWRITE))
 145                     status |= SSI_SDR_OUT_OF_RANGE;
 146                 /* ??? Don't know what Parameter Error really means, so
 147                    assume it's set if the second byte is nonzero.  */
 148                 if (status & 0xff)
 149                     status |= SSI_SDR_PARAMETER_ERROR;
 150                 s->response[0] = status >> 8;
 151                 s->response[1] = status;
 152                 DPRINTF("Card status 0x%02x\n", status);
 153             }
 154             s->mode = SSI_SD_RESPONSE;
 155             s->response_pos = 0;
 156         } else {
 157             s->cmdarg[s->arglen++] = val;
 158         }
 159         return 0xff;
 160     case SSI_SD_RESPONSE:
 161         if (s->stopping) {
 162             s->stopping = 0;
 163             return 0xff;
 164         }
 165         if (s->response_pos < s->arglen) {
 166             DPRINTF("Response 0x%02x\n", s->response[s->response_pos]);
 167             return s->response[s->response_pos++];
 168         }
 169         if (sd_data_ready(s->sd)) {
 170             DPRINTF("Data read\n");
 171             s->mode = SSI_SD_DATA_START;
 172         } else {
 173             DPRINTF("End of command\n");
 174             s->mode = SSI_SD_CMD;
 175         }
 176         return 0xff;
 177     case SSI_SD_DATA_START:
 178         DPRINTF("Start read block\n");
 179         s->mode = SSI_SD_DATA_READ;
 180         return 0xfe;
 181     case SSI_SD_DATA_READ:
 182         val = sd_read_data(s->sd);
 183         if (!sd_data_ready(s->sd)) {
 184             DPRINTF("Data read end\n");
 185             s->mode = SSI_SD_CMD;
 186         }
 187         return val;
 188     }
 189     /* Should never happen.  */
 190     return 0xff;
 191 }
 192
 193 void *ssi_sd_init(BlockDriverState *bs)
 194 {
 195     ssi_sd_state *s;
 196
 197     s = (ssi_sd_state *)qemu_mallocz(sizeof(ssi_sd_state));
 198     s->mode = SSI_SD_CMD;
 199     s->sd = sd_init(bs, 1);
 200     return s;
 201 }
 202