drivers/raw/ifpga_rawdev/base/opae_spi_transaction.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2010-2019 Intel Corporation
   3  */
   4
   5 #include "opae_spi.h"
   6 #include "ifpga_compat.h"
   7
   8 /*transaction opcodes*/
   9 #define SPI_TRAN_SEQ_WRITE 0x04 /* SPI transaction sequential write */
  10 #define SPI_TRAN_SEQ_READ  0x14 /* SPI transaction sequential read */
  11 #define SPI_TRAN_NON_SEQ_WRITE 0x00 /* SPI transaction non-sequential write */
  12 #define SPI_TRAN_NON_SEQ_READ  0x10 /* SPI transaction non-sequential read*/
  13
  14 /*specail packet characters*/
  15 #define SPI_PACKET_SOP     0x7a
  16 #define SPI_PACKET_EOP     0x7b
  17 #define SPI_PACKET_CHANNEL 0x7c
  18 #define SPI_PACKET_ESC     0x7d
  19
  20 /*special byte characters*/
  21 #define SPI_BYTE_IDLE 0x4a
  22 #define SPI_BYTE_ESC  0x4d
  23
  24 #define SPI_REG_BYTES 4
  25
  26 #define INIT_SPI_TRAN_HEADER(trans_type, size, address) \
  27 ({ \
  28         header.trans_type = trans_type; \
  29         header.reserve = 0; \
  30         header.size = cpu_to_be16(size); \
  31         header.addr = cpu_to_be32(addr); \
  32 })
  33
  34 #ifdef OPAE_SPI_DEBUG
  35 static void print_buffer(const char *string, void *buffer, int len)
  36 {
  37         int i;
  38         unsigned char *p = buffer;
  39
  40         printf("%s print buffer, len=%d\n", string, len);
  41
  42         for (i = 0; i < len; i++)
  43                 printf("%x ", *(p+i));
  44         printf("\n");
  45 }
  46 #else
  47 static void print_buffer(const char *string, void *buffer, int len)
  48 {
  49         UNUSED(string);
  50         UNUSED(buffer);
  51         UNUSED(len);
  52 }
  53 #endif
  54
  55 static unsigned char xor_20(unsigned char val)
  56 {
  57         return val^0x20;
  58 }
  59
  60 static void reorder_phy_data(u8 bits_per_word,
  61                 void *buf, unsigned int len)
  62 {
  63         unsigned int count = len / (bits_per_word/8);
  64         u32 *p;
  65
  66         if (bits_per_word == 32) {
  67                 p = (u32 *)buf;
  68                 while (count--) {
  69                         *p = cpu_to_be32(*p);
  70                         p++;
  71                 }
  72         }
  73 }
  74
  75 enum {
  76         SPI_FOUND_SOP,
  77         SPI_FOUND_EOP,
  78         SPI_NOT_FOUND,
  79 };
  80
  81 static int resp_find_sop_eop(unsigned char *resp, unsigned int len,
  82                 int flags)
  83 {
  84         int ret = SPI_NOT_FOUND;
  85
  86         unsigned char *b = resp;
  87
  88         /* find SOP */
  89         if (flags != SPI_FOUND_SOP) {
  90                 while (b < resp + len && *b != SPI_PACKET_SOP)
  91                         b++;
  92
  93                 if (*b != SPI_PACKET_SOP)
  94                         goto done;
  95
  96                 ret = SPI_FOUND_SOP;
  97         }
  98
  99         /* find EOP */
 100         while (b < resp + len && *b != SPI_PACKET_EOP)
 101                 b++;
 102
 103         if (*b != SPI_PACKET_EOP)
 104                 goto done;
 105
 106         ret = SPI_FOUND_EOP;
 107
 108 done:
 109         return ret;
 110 }
 111
 112 static int byte_to_core_convert(struct spi_transaction_dev *dev,
 113                 unsigned int send_len, unsigned char *send_data,
 114                 unsigned int resp_len, unsigned char *resp_data,
 115                 unsigned int *valid_resp_len)
 116 {
 117         unsigned int i;
 118         int ret = 0;
 119         unsigned char *send_packet = dev->buffer->bytes_send;
 120         unsigned char *resp_packet = dev->buffer->bytes_resp;
 121         unsigned char *p;
 122         unsigned char current_byte;
 123         unsigned char *tx_buffer;
 124         unsigned int tx_len = 0;
 125         unsigned char *rx_buffer;
 126         unsigned int rx_len = 0;
 127         int retry = 0;
 128         int spi_flags;
 129         unsigned int resp_max_len = 2 * resp_len;
 130
 131         print_buffer("before bytes:", send_data, send_len);
 132
 133         p = send_packet;
 134
 135         for (i = 0; i < send_len; i++) {
 136                 current_byte = send_data[i];
 137                 switch (current_byte) {
 138                 case SPI_BYTE_IDLE:
 139                         *p++ = SPI_BYTE_IDLE;
 140                         *p++ = xor_20(current_byte);
 141                         break;
 142                 case SPI_BYTE_ESC:
 143                         *p++ = SPI_BYTE_ESC;
 144                         *p++ = xor_20(current_byte);
 145                         break;
 146                 default:
 147                         *p++ = current_byte;
 148                         break;
 149                 }
 150         }
 151
 152         print_buffer("before spi:", send_packet, p-send_packet);
 153
 154         reorder_phy_data(32, send_packet, p - send_packet);
 155
 156         print_buffer("after order to spi:", send_packet, p-send_packet);
 157
 158         /* call spi */
 159         tx_buffer = send_packet;
 160         tx_len = p - send_packet;
 161         rx_buffer = resp_packet;
 162         rx_len = resp_max_len;
 163         spi_flags = SPI_NOT_FOUND;
 164
 165 read_again:
 166         ret = spi_command(dev->dev, dev->chipselect, tx_len, tx_buffer,
 167                         rx_len, rx_buffer);
 168         if (ret)
 169                 return -EBUSY;
 170
 171         print_buffer("read from spi:", rx_buffer, rx_len);
 172
 173         /* look for SOP firstly*/
 174         ret = resp_find_sop_eop(rx_buffer, rx_len - 1, spi_flags);
 175         if (ret != SPI_FOUND_EOP) {
 176                 tx_buffer = NULL;
 177                 tx_len = 0;
 178                 if (retry++ > 10) {
 179                         dev_err(NULL, "cannot found valid data from SPI\n");
 180                         return -EBUSY;
 181                 }
 182
 183                 if (ret == SPI_FOUND_SOP) {
 184                         rx_buffer += rx_len;
 185                         resp_max_len += rx_len;
 186                 }
 187
 188                 spi_flags = ret;
 189                 goto read_again;
 190         }
 191
 192         print_buffer("found valid data:", resp_packet, resp_max_len);
 193
 194         /* analyze response packet */
 195         i = 0;
 196         p = resp_data;
 197         while (i < resp_max_len) {
 198                 current_byte = resp_packet[i];
 199                 switch (current_byte) {
 200                 case SPI_BYTE_IDLE:
 201                         i++;
 202                         break;
 203                 case SPI_BYTE_ESC:
 204                         i++;
 205                         current_byte = resp_packet[i];
 206                         *p++ = xor_20(current_byte);
 207                         i++;
 208                         break;
 209                 default:
 210                         *p++ = current_byte;
 211                         i++;
 212                         break;
 213                 }
 214         }
 215
 216         /* receive "4a" means the SPI is idle, not valid data */
 217         *valid_resp_len = p - resp_data;
 218         if (*valid_resp_len == 0) {
 219                 dev_err(NULL, "error: repond package without valid data\n");
 220                 return -EINVAL;
 221         }
 222
 223         return 0;
 224 }
 225
 226 static int packet_to_byte_conver(struct spi_transaction_dev *dev,
 227                 unsigned int send_len, unsigned char *send_buf,
 228                 unsigned int resp_len, unsigned char *resp_buf,
 229                 unsigned int *valid)
 230 {
 231         int ret = 0;
 232         unsigned int i;
 233         unsigned char current_byte;
 234         unsigned int resp_max_len;
 235         unsigned char *send_packet = dev->buffer->packet_send;
 236         unsigned char *resp_packet = dev->buffer->packet_resp;
 237         unsigned char *p;
 238         unsigned int valid_resp_len = 0;
 239
 240         print_buffer("before packet:", send_buf, send_len);
 241
 242         resp_max_len = 2 * resp_len + 4;
 243
 244         p = send_packet;
 245
 246         /* SOP header */
 247         *p++ = SPI_PACKET_SOP;
 248
 249         *p++ = SPI_PACKET_CHANNEL;
 250         *p++ = 0;
 251
 252         /* append the data into a packet */
 253         for (i = 0; i < send_len; i++) {
 254                 current_byte = send_buf[i];
 255
 256                 /* EOP for last byte */
 257                 if (i == send_len - 1)
 258                         *p++ = SPI_PACKET_EOP;
 259
 260                 switch (current_byte) {
 261                 case SPI_PACKET_SOP:
 262                 case SPI_PACKET_EOP:
 263                 case SPI_PACKET_CHANNEL:
 264                 case SPI_PACKET_ESC:
 265                         *p++ = SPI_PACKET_ESC;
 266                         *p++ = xor_20(current_byte);
 267                         break;
 268                 default:
 269                         *p++ = current_byte;
 270                 }
 271         }
 272
 273         ret = byte_to_core_convert(dev, p - send_packet,
 274                         send_packet, resp_max_len, resp_packet,
 275                         &valid_resp_len);
 276         if (ret)
 277                 return -EBUSY;
 278
 279         print_buffer("after byte conver:", resp_packet, valid_resp_len);
 280
 281         /* analyze the response packet */
 282         p = resp_buf;
 283
 284         /* look for SOP */
 285         for (i = 0; i < valid_resp_len; i++) {
 286                 if (resp_packet[i] == SPI_PACKET_SOP)
 287                         break;
 288         }
 289
 290         if (i == valid_resp_len) {
 291                 dev_err(NULL, "error on analyze response packet 0x%x\n",
 292                                 resp_packet[i]);
 293                 return -EINVAL;
 294         }
 295
 296         i++;
 297
 298         /* continue parsing data after SOP */
 299         while (i < valid_resp_len) {
 300                 current_byte = resp_packet[i];
 301
 302                 switch (current_byte) {
 303                 case SPI_PACKET_ESC:
 304                 case SPI_PACKET_CHANNEL:
 305                 case SPI_PACKET_SOP:
 306                         i++;
 307                         current_byte = resp_packet[i];
 308                         *p++ = xor_20(current_byte);
 309                         i++;
 310                         break;
 311                 case SPI_PACKET_EOP:
 312                         i++;
 313                         current_byte = resp_packet[i];
 314                         if (current_byte == SPI_PACKET_ESC ||
 315                                         current_byte == SPI_PACKET_CHANNEL ||
 316                                         current_byte == SPI_PACKET_SOP) {
 317                                 i++;
 318                                 current_byte = resp_packet[i];
 319                                 *p++ = xor_20(current_byte);
 320                         } else
 321                                 *p++ = current_byte;
 322                         i = valid_resp_len;
 323                         break;
 324                 default:
 325                         *p++ = current_byte;
 326                         i++;
 327                 }
 328
 329         }
 330
 331         *valid = p - resp_buf;
 332
 333         print_buffer("after packet:", resp_buf, *valid);
 334
 335         return ret;
 336 }
 337
 338 static int do_transaction(struct spi_transaction_dev *dev, unsigned int addr,
 339                 unsigned int size, unsigned char *data,
 340                 unsigned int trans_type)
 341 {
 342
 343         struct spi_tran_header header;
 344         unsigned char *transaction = dev->buffer->tran_send;
 345         unsigned char *response = dev->buffer->tran_resp;
 346         unsigned char *p;
 347         int ret = 0;
 348         unsigned int i;
 349         unsigned int valid_len = 0;
 350
 351         /* make transacation header */
 352         INIT_SPI_TRAN_HEADER(trans_type, size, addr);
 353
 354         /* fill the header */
 355         p = transaction;
 356         opae_memcpy(p, &header, sizeof(struct spi_tran_header));
 357         p = p + sizeof(struct spi_tran_header);
 358
 359         switch (trans_type) {
 360         case SPI_TRAN_SEQ_WRITE:
 361         case SPI_TRAN_NON_SEQ_WRITE:
 362                 for (i = 0; i < size; i++)
 363                         *p++ = *data++;
 364
 365                 ret = packet_to_byte_conver(dev, size + HEADER_LEN,
 366                                 transaction, RESPONSE_LEN, response,
 367                                 &valid_len);
 368                 if (ret)
 369                         return -EBUSY;
 370
 371                 /* check the result */
 372                 if (size != ((unsigned int)(response[2] & 0xff) << 8 |
 373                         (unsigned int)(response[3] & 0xff)))
 374                         ret = -EBUSY;
 375
 376                 break;
 377         case SPI_TRAN_SEQ_READ:
 378         case SPI_TRAN_NON_SEQ_READ:
 379                 ret = packet_to_byte_conver(dev, HEADER_LEN,
 380                                 transaction, size, response,
 381                                 &valid_len);
 382                 if (ret || valid_len != size)
 383                         return -EBUSY;
 384
 385                 for (i = 0; i < size; i++)
 386                         *data++ = *response++;
 387
 388                 ret = 0;
 389                 break;
 390         }
 391
 392         return ret;
 393 }
 394
 395 int spi_transaction_read(struct spi_transaction_dev *dev, unsigned int addr,
 396                 unsigned int size, unsigned char *data)
 397 {
 398         return do_transaction(dev, addr, size, data,
 399                         (size > SPI_REG_BYTES) ?
 400                         SPI_TRAN_SEQ_READ : SPI_TRAN_NON_SEQ_READ);
 401 }
 402
 403 int spi_transaction_write(struct spi_transaction_dev *dev, unsigned int addr,
 404                 unsigned int size, unsigned char *data)
 405 {
 406         return do_transaction(dev, addr, size, data,
 407                         (size > SPI_REG_BYTES) ?
 408                         SPI_TRAN_SEQ_WRITE : SPI_TRAN_NON_SEQ_WRITE);
 409 }
 410
 411 struct spi_transaction_dev *spi_transaction_init(struct altera_spi_device *dev,
 412                 int chipselect)
 413 {
 414         struct spi_transaction_dev *spi_tran_dev;
 415
 416         spi_tran_dev = opae_malloc(sizeof(struct spi_transaction_dev));
 417         if (!spi_tran_dev)
 418                 return NULL;
 419
 420         spi_tran_dev->dev = dev;
 421         spi_tran_dev->chipselect = chipselect;
 422
 423         spi_tran_dev->buffer = opae_malloc(sizeof(struct spi_tran_buffer));
 424         if (!spi_tran_dev->buffer) {
 425                 opae_free(spi_tran_dev);
 426                 return NULL;
 427         }
 428
 429         return spi_tran_dev;
 430 }
 431
 432 void spi_transaction_remove(struct spi_transaction_dev *dev)
 433 {
 434         if (dev && dev->buffer)
 435                 opae_free(dev->buffer);
 436         if (dev)
 437                 opae_free(dev);
 438 }