examples/eepro100_eeprom.c

   1 /*
   2  * Copyright 1998-2001 by Donald Becker.
   3  * This software may be used and distributed according to the terms of
   4  * the GNU General Public License (GPL), incorporated herein by reference.
   5  * Contact the author for use under other terms.
   6  *
   7  * This program must be compiled with "-O"!
   8  * See the bottom of this file for the suggested compile-command.
   9  *
  10  * The author may be reached as becker@scyld.com, or C/O
  11  *  Scyld Computing Corporation
  12  *  410 Severn Ave., Suite 210
  13  *  Annapolis MD 21403
  14  *
  15  * Common-sense licensing statement: Using any portion of this program in
  16  * your own program means that you must give credit to the original author
  17  * and release the resulting code under the GPL.
  18  */
  19
  20 #define _PPC_STRING_H_          /* avoid unnecessary str/mem functions */
  21 #define _LINUX_STRING_H_        /* avoid unnecessary str/mem functions */
  22
  23 #include <common.h>
  24 #include <syscall.h>
  25
  26 static int reset_eeprom(unsigned long ioaddr, unsigned char *hwaddr);
  27
  28 int eepro100_eeprom(void)
  29 {
  30         int ret = 0;
  31
  32         unsigned char hwaddr1[6] = { 0x00, 0x00, 0x02, 0x03, 0x04, 0x05 };
  33         unsigned char hwaddr2[6] = { 0x00, 0x00, 0x02, 0x03, 0x04, 0x06 };
  34
  35 #if defined(CONFIG_OXC)
  36         ret |= reset_eeprom(0x80000000, hwaddr1);
  37         ret |= reset_eeprom(0x81000000, hwaddr2);
  38 #endif
  39
  40         return ret;
  41 }
  42
  43 /* Default EEPROM for i82559 */
  44 static unsigned short default_eeprom[64] = {
  45         0x0100, 0x0302, 0x0504, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  46         0xffff, 0xffff, 0x40c0, 0x0000, 0x0000, 0xffff, 0xffff, 0xffff,
  47         0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  48         0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  49         0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  50         0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  51         0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  52         0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff
  53 };
  54
  55 static unsigned short eeprom[256];
  56
  57 static int eeprom_size = 64;
  58 static int eeprom_addr_size = 6;
  59
  60 static int debug = 0;
  61
  62 static inline unsigned short swap16(unsigned short x)
  63 {
  64         return (((x & 0xff) << 8) | ((x & 0xff00) >> 8));
  65 }
  66
  67 static inline void outw(short data, long addr)
  68 {
  69         *(volatile short *)(addr) = swap16(data);
  70 }
  71
  72 static inline short inw(long addr)
  73 {
  74         return swap16(*(volatile short *)(addr));
  75 }
  76
  77 static inline void *memcpy(void *dst, const void *src, unsigned int len)
  78 {
  79         void * ret = dst;
  80         while (len-- > 0) *((char *)dst)++ = *((char *)src)++;
  81         return ret;
  82 }
  83
  84 /* The EEPROM commands include the alway-set leading bit. */
  85 #define EE_WRITE_CMD    (5)
  86 #define EE_READ_CMD             (6)
  87 #define EE_ERASE_CMD    (7)
  88
  89 /* Serial EEPROM section. */
  90 #define EE_SHIFT_CLK    0x01    /* EEPROM shift clock. */
  91 #define EE_CS                   0x02    /* EEPROM chip select. */
  92 #define EE_DATA_WRITE   0x04    /* EEPROM chip data in. */
  93 #define EE_DATA_READ    0x08    /* EEPROM chip data out. */
  94 #define EE_ENB                  (0x4800 | EE_CS)
  95 #define EE_WRITE_0              0x4802
  96 #define EE_WRITE_1              0x4806
  97 #define EE_OFFSET               14
  98
  99 /* Delay between EEPROM clock transitions. */
 100 #define eeprom_delay(ee_addr)   inw(ee_addr)
 101
 102 /* Wait for the EEPROM to finish the previous operation. */
 103 static int eeprom_busy_poll(long ee_ioaddr)
 104 {
 105         int i;
 106         outw(EE_ENB, ee_ioaddr);
 107         for (i = 0; i < 10000; i++)                     /* Typical 2000 ticks */
 108                 if (inw(ee_ioaddr) & EE_DATA_READ)
 109                         break;
 110         return i;
 111 }
 112
 113 /* This executes a generic EEPROM command, typically a write or write enable.
 114    It returns the data output from the EEPROM, and thus may also be used for
 115    reads. */
 116 static int do_eeprom_cmd(long ioaddr, int cmd, int cmd_len)
 117 {
 118         unsigned retval = 0;
 119         long ee_addr = ioaddr + EE_OFFSET;
 120
 121         if (debug > 1)
 122                 mon_printf(" EEPROM op 0x%x: ", cmd);
 123
 124         outw(EE_ENB | EE_SHIFT_CLK, ee_addr);
 125
 126         /* Shift the command bits out. */
 127         do {
 128                 short dataval = (cmd & (1 << cmd_len)) ? EE_WRITE_1 : EE_WRITE_0;
 129                 outw(dataval, ee_addr);
 130                 eeprom_delay(ee_addr);
 131                 if (debug > 2)
 132                         mon_printf("%X", inw(ee_addr) & 15);
 133                 outw(dataval | EE_SHIFT_CLK, ee_addr);
 134                 eeprom_delay(ee_addr);
 135                 retval = (retval << 1) | ((inw(ee_addr) & EE_DATA_READ) ? 1 : 0);
 136         } while (--cmd_len >= 0);
 137 #if 0
 138         outw(EE_ENB, ee_addr);
 139 #endif
 140         /* Terminate the EEPROM access. */
 141         outw(EE_ENB & ~EE_CS, ee_addr);
 142         if (debug > 1)
 143                 mon_printf(" EEPROM result is 0x%5.5x.\n", retval);
 144         return retval;
 145 }
 146
 147 static int read_eeprom(long ioaddr, int location, int addr_len)
 148 {
 149         return do_eeprom_cmd(ioaddr, ((EE_READ_CMD << addr_len) | location)
 150                 << 16 , 3 + addr_len + 16) & 0xffff;
 151 }
 152
 153 static void write_eeprom(long ioaddr, int index, int value, int addr_len)
 154 {
 155         long ee_ioaddr = ioaddr + EE_OFFSET;
 156         int i;
 157
 158         /* Poll for previous op finished. */
 159         eeprom_busy_poll(ee_ioaddr);                    /* Typical 0 ticks */
 160         /* Enable programming modes. */
 161         do_eeprom_cmd(ioaddr, (0x4f << (addr_len-4)), 3 + addr_len);
 162         /* Do the actual write. */
 163         do_eeprom_cmd(ioaddr,
 164                                   (((EE_WRITE_CMD<<addr_len) | index)<<16) | (value & 0xffff),
 165                                   3 + addr_len + 16);
 166         /* Poll for write finished. */
 167         i = eeprom_busy_poll(ee_ioaddr);                        /* Typical 2000 ticks */
 168         if (debug)
 169                 mon_printf(" Write finished after %d ticks.\n", i);
 170         /* Disable programming. This command is not instantaneous, so we check
 171            for busy before the next op. */
 172         do_eeprom_cmd(ioaddr, (0x40 << (addr_len-4)), 3 + addr_len);
 173         eeprom_busy_poll(ee_ioaddr);
 174 }
 175
 176 static int reset_eeprom(unsigned long ioaddr, unsigned char *hwaddr)
 177 {
 178         unsigned short checksum = 0;
 179         int size_test;
 180         int i;
 181
 182         mon_printf("Resetting i82559 EEPROM @ 0x%08x ... ", ioaddr);
 183
 184         size_test = do_eeprom_cmd(ioaddr, (EE_READ_CMD << 8) << 16, 27);
 185         eeprom_addr_size = (size_test & 0xffe0000) == 0xffe0000 ? 8 : 6;
 186         eeprom_size = 1 << eeprom_addr_size;
 187
 188         memcpy(eeprom, default_eeprom, sizeof default_eeprom);
 189
 190         for (i = 0; i < 3; i++)
 191                 eeprom[i] = (hwaddr[i*2+1]<<8) + hwaddr[i*2];
 192
 193         /* Recalculate the checksum. */
 194         for (i = 0; i < eeprom_size - 1; i++)
 195                 checksum += eeprom[i];
 196         eeprom[i] = 0xBABA - checksum;
 197
 198         for (i = 0; i < eeprom_size; i++)
 199                 write_eeprom(ioaddr, i, eeprom[i], eeprom_addr_size);
 200
 201         for (i = 0; i < eeprom_size; i++)
 202                 if (read_eeprom(ioaddr, i, eeprom_addr_size) != eeprom[i]) {
 203                         mon_printf("failed\n");
 204                         return 1;
 205                 }
 206
 207         mon_printf("done\n");
 208         return 0;
 209 }