drivers/mtd/spi/spi_flash.c

   1 /*
   2  * SPI flash interface
   3  *
   4  * Copyright (C) 2008 Atmel Corporation
   5  * Copyright (C) 2010 Reinhard Meyer, EMK Elektronik
   6  *
   7  * Licensed under the GPL-2 or later.
   8  */
   9
  10 #include <common.h>
  11 #include <malloc.h>
  12 #include <spi.h>
  13 #include <spi_flash.h>
  14
  15 #include "spi_flash_internal.h"
  16
  17 int spi_flash_cmd(struct spi_slave *spi, u8 cmd, void *response, size_t len)
  18 {
  19         unsigned long flags = SPI_XFER_BEGIN;
  20         int ret;
  21
  22         if (len == 0)
  23                 flags |= SPI_XFER_END;
  24
  25         ret = spi_xfer(spi, 8, &cmd, NULL, flags);
  26         if (ret) {
  27                 debug("SF: Failed to send command %02x: %d\n", cmd, ret);
  28                 return ret;
  29         }
  30
  31         if (len) {
  32                 ret = spi_xfer(spi, len * 8, NULL, response, SPI_XFER_END);
  33                 if (ret)
  34                         debug("SF: Failed to read response (%zu bytes): %d\n",
  35                                         len, ret);
  36         }
  37
  38         return ret;
  39 }
  40
  41 int spi_flash_cmd_read(struct spi_slave *spi, const u8 *cmd,
  42                 size_t cmd_len, void *data, size_t data_len)
  43 {
  44         unsigned long flags = SPI_XFER_BEGIN;
  45         int ret;
  46
  47         if (data_len == 0)
  48                 flags |= SPI_XFER_END;
  49
  50         ret = spi_xfer(spi, cmd_len * 8, cmd, NULL, flags);
  51         if (ret) {
  52                 debug("SF: Failed to send read command (%zu bytes): %d\n",
  53                                 cmd_len, ret);
  54         } else if (data_len != 0) {
  55                 ret = spi_xfer(spi, data_len * 8, NULL, data, SPI_XFER_END);
  56                 if (ret)
  57                         debug("SF: Failed to read %zu bytes of data: %d\n",
  58                                         data_len, ret);
  59         }
  60
  61         return ret;
  62 }
  63
  64 int spi_flash_cmd_write(struct spi_slave *spi, const u8 *cmd, size_t cmd_len,
  65                 const void *data, size_t data_len)
  66 {
  67         unsigned long flags = SPI_XFER_BEGIN;
  68         int ret;
  69
  70         if (data_len == 0)
  71                 flags |= SPI_XFER_END;
  72
  73         ret = spi_xfer(spi, cmd_len * 8, cmd, NULL, flags);
  74         if (ret) {
  75                 debug("SF: Failed to send read command (%zu bytes): %d\n",
  76                                 cmd_len, ret);
  77         } else if (data_len != 0) {
  78                 ret = spi_xfer(spi, data_len * 8, data, NULL, SPI_XFER_END);
  79                 if (ret)
  80                         debug("SF: Failed to read %zu bytes of data: %d\n",
  81                                         data_len, ret);
  82         }
  83
  84         return ret;
  85 }
  86
  87
  88 int spi_flash_read_common(struct spi_flash *flash, const u8 *cmd,
  89                 size_t cmd_len, void *data, size_t data_len)
  90 {
  91         struct spi_slave *spi = flash->spi;
  92         int ret;
  93
  94         spi_claim_bus(spi);
  95         ret = spi_flash_cmd_read(spi, cmd, cmd_len, data, data_len);
  96         spi_release_bus(spi);
  97
  98         return ret;
  99 }
 100
 101 /*
 102  * The following table holds all device probe functions
 103  *
 104  * shift:  number of continuation bytes before the ID
 105  * idcode: the expected IDCODE or 0xff for non JEDEC devices
 106  * probe:  the function to call
 107  *
 108  * Non JEDEC devices should be ordered in the table such that
 109  * the probe functions with best detection algorithms come first.
 110  *
 111  * Several matching entries are permitted, they will be tried
 112  * in sequence until a probe function returns non NULL.
 113  *
 114  * IDCODE_CONT_LEN may be redefined if a device needs to declare a
 115  * larger "shift" value.  IDCODE_PART_LEN generally shouldn't be
 116  * changed.  This is the max number of bytes probe functions may
 117  * examine when looking up part-specific identification info.
 118  *
 119  * Probe functions will be given the idcode buffer starting at their
 120  * manu id byte (the "idcode" in the table below).  In other words,
 121  * all of the continuation bytes will be skipped (the "shift" below).
 122  */
 123 #define IDCODE_CONT_LEN 0
 124 #define IDCODE_PART_LEN 5
 125 static const struct {
 126         const u8 shift;
 127         const u8 idcode;
 128         struct spi_flash *(*probe) (struct spi_slave *spi, u8 *idcode);
 129 } flashes[] = {
 130         /* Keep it sorted by define name */
 131 #ifdef CONFIG_SPI_FLASH_ATMEL
 132         { 0, 0x1f, spi_flash_probe_atmel, },
 133 #endif
 134 #ifdef CONFIG_SPI_FLASH_MACRONIX
 135         { 0, 0xc2, spi_flash_probe_macronix, },
 136 #endif
 137 #ifdef CONFIG_SPI_FLASH_SPANSION
 138         { 0, 0x01, spi_flash_probe_spansion, },
 139 #endif
 140 #ifdef CONFIG_SPI_FLASH_SST
 141         { 0, 0xbf, spi_flash_probe_sst, },
 142 #endif
 143 #ifdef CONFIG_SPI_FLASH_STMICRO
 144         { 0, 0x20, spi_flash_probe_stmicro, },
 145 #endif
 146 #ifdef CONFIG_SPI_FLASH_WINBOND
 147         { 0, 0xef, spi_flash_probe_winbond, },
 148 #endif
 149         /* Keep it sorted by best detection */
 150 #ifdef CONFIG_SPI_FLASH_STMICRO
 151         { 0, 0xff, spi_flash_probe_stmicro, },
 152 #endif
 153 };
 154 #define IDCODE_LEN (IDCODE_CONT_LEN + IDCODE_PART_LEN)
 155
 156 struct spi_flash *spi_flash_probe(unsigned int bus, unsigned int cs,
 157                 unsigned int max_hz, unsigned int spi_mode)
 158 {
 159         struct spi_slave *spi;
 160         struct spi_flash *flash = NULL;
 161         int ret, i, shift;
 162         u8 idcode[IDCODE_LEN], *idp;
 163
 164         spi = spi_setup_slave(bus, cs, max_hz, spi_mode);
 165         if (!spi) {
 166                 printf("SF: Failed to set up slave\n");
 167                 return NULL;
 168         }
 169
 170         ret = spi_claim_bus(spi);
 171         if (ret) {
 172                 debug("SF: Failed to claim SPI bus: %d\n", ret);
 173                 goto err_claim_bus;
 174         }
 175
 176         /* Read the ID codes */
 177         ret = spi_flash_cmd(spi, CMD_READ_ID, idcode, sizeof(idcode));
 178         if (ret)
 179                 goto err_read_id;
 180
 181 #ifdef DEBUG
 182         printf("SF: Got idcodes\n");
 183         print_buffer(0, idcode, 1, sizeof(idcode), 0);
 184 #endif
 185
 186         /* count the number of continuation bytes */
 187         for (shift = 0, idp = idcode;
 188              shift < IDCODE_CONT_LEN && *idp == 0x7f;
 189              ++shift, ++idp)
 190                 continue;
 191
 192         /* search the table for matches in shift and id */
 193         for (i = 0; i < ARRAY_SIZE(flashes); ++i)
 194                 if (flashes[i].shift == shift && flashes[i].idcode == *idp) {
 195                         /* we have a match, call probe */
 196                         flash = flashes[i].probe(spi, idp);
 197                         if (flash)
 198                                 break;
 199                 }
 200
 201         if (!flash) {
 202                 printf("SF: Unsupported manufacturer %02x\n", *idp);
 203                 goto err_manufacturer_probe;
 204         }
 205
 206         spi_release_bus(spi);
 207
 208         return flash;
 209
 210 err_manufacturer_probe:
 211 err_read_id:
 212         spi_release_bus(spi);
 213 err_claim_bus:
 214         spi_free_slave(spi);
 215         return NULL;
 216 }
 217
 218 void spi_flash_free(struct spi_flash *flash)
 219 {
 220         spi_free_slave(flash->spi);
 221         free(flash);
 222 }