drivers/atm/nicstarmac.c

   1 /*
   2  * this file included by nicstar.c
   3  */
   4
   5 /*
   6  * nicstarmac.c
   7  * Read this ForeRunner's MAC address from eprom/eeprom
   8  */
   9
  10 #define CYCLE_DELAY 5
  11
  12 /* This was the original definition
  13 #define osp_MicroDelay(microsec) \
  14     do { int _i = 4*microsec; while (--_i > 0) { __SLOW_DOWN_IO; }} while (0)
  15 */
  16 #define osp_MicroDelay(microsec) {unsigned long useconds = (microsec); \
  17                                   udelay((useconds));}
  18
  19
  20 /* The following tables represent the timing diagrams found in
  21  * the Data Sheet for the Xicor X25020 EEProm.  The #defines below
  22  * represent the bits in the NICStAR's General Purpose register
  23  * that must be toggled for the corresponding actions on the EEProm
  24  * to occur.
  25  */
  26
  27 /* Write Data To EEProm from SI line on rising edge of CLK */
  28 /* Read Data From EEProm on falling edge of CLK */
  29
  30 #define CS_HIGH         0x0002          /* Chip select high */
  31 #define CS_LOW          0x0000          /* Chip select low (active low)*/
  32 #define CLK_HIGH        0x0004          /* Clock high */
  33 #define CLK_LOW         0x0000          /* Clock low  */
  34 #define SI_HIGH         0x0001          /* Serial input data high */
  35 #define SI_LOW          0x0000          /* Serial input data low */
  36
  37 /* Read Status Register = 0000 0101b */
  38 static u_int32_t rdsrtab[] =
  39 {
  40     CS_HIGH | CLK_HIGH,
  41     CS_LOW | CLK_LOW,
  42     CLK_HIGH,             /* 0 */
  43     CLK_LOW,
  44     CLK_HIGH,             /* 0 */
  45     CLK_LOW,
  46     CLK_HIGH,             /* 0 */
  47     CLK_LOW,
  48     CLK_HIGH,             /* 0 */
  49     CLK_LOW,
  50     CLK_HIGH,             /* 0 */
  51     CLK_LOW | SI_HIGH,
  52     CLK_HIGH | SI_HIGH,   /* 1 */
  53     CLK_LOW | SI_LOW,
  54     CLK_HIGH,             /* 0 */
  55     CLK_LOW | SI_HIGH,
  56     CLK_HIGH | SI_HIGH   /* 1 */
  57 };
  58
  59
  60 /* Read from EEPROM = 0000 0011b */
  61 static u_int32_t readtab[] =
  62 {
  63     /*
  64     CS_HIGH | CLK_HIGH,
  65     */
  66     CS_LOW | CLK_LOW,
  67     CLK_HIGH,             /* 0 */
  68     CLK_LOW,
  69     CLK_HIGH,             /* 0 */
  70     CLK_LOW,
  71     CLK_HIGH,             /* 0 */
  72     CLK_LOW,
  73     CLK_HIGH,             /* 0 */
  74     CLK_LOW,
  75     CLK_HIGH,             /* 0 */
  76     CLK_LOW,
  77     CLK_HIGH,             /* 0 */
  78     CLK_LOW | SI_HIGH,
  79     CLK_HIGH | SI_HIGH,   /* 1 */
  80     CLK_LOW | SI_HIGH,
  81     CLK_HIGH | SI_HIGH    /* 1 */
  82 };
  83
  84
  85 /* Clock to read from/write to the eeprom */
  86 static u_int32_t clocktab[] =
  87 {
  88     CLK_LOW,
  89     CLK_HIGH,
  90     CLK_LOW,
  91     CLK_HIGH,
  92     CLK_LOW,
  93     CLK_HIGH,
  94     CLK_LOW,
  95     CLK_HIGH,
  96     CLK_LOW,
  97     CLK_HIGH,
  98     CLK_LOW,
  99     CLK_HIGH,
 100     CLK_LOW,
 101     CLK_HIGH,
 102     CLK_LOW,
 103     CLK_HIGH,
 104     CLK_LOW
 105 };
 106
 107
 108 #define NICSTAR_REG_WRITE(bs, reg, val) \
 109         while ( readl(bs + STAT) & 0x0200 ) ; \
 110         writel((val),(base)+(reg))
 111 #define NICSTAR_REG_READ(bs, reg) \
 112         readl((base)+(reg))
 113 #define NICSTAR_REG_GENERAL_PURPOSE GP
 114
 115 /*
 116  * This routine will clock the Read_Status_reg function into the X2520
 117  * eeprom, then pull the result from bit 16 of the NicSTaR's General Purpose
 118  * register.
 119  */
 120
 121 u_int32_t
 122 nicstar_read_eprom_status( virt_addr_t base )
 123 {
 124    u_int32_t    val;
 125    u_int32_t    rbyte;
 126    int32_t      i, j;
 127
 128    /* Send read instruction */
 129    val = NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE ) & 0xFFFFFFF0;
 130
 131    for (i=0; i<sizeof rdsrtab/sizeof rdsrtab[0]; i++)
 132    {
 133         NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 134                 (val | rdsrtab[i]) );
 135         osp_MicroDelay( CYCLE_DELAY );
 136    }
 137
 138    /* Done sending instruction - now pull data off of bit 16, MSB first */
 139    /* Data clocked out of eeprom on falling edge of clock */
 140
 141    rbyte = 0;
 142    for (i=7, j=0; i>=0; i--)
 143    {
 144         NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 145                 (val | clocktab[j++]) );
 146         rbyte |= (((NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE)
 147                         & 0x00010000) >> 16) << i);
 148         NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 149                 (val | clocktab[j++]) );
 150         osp_MicroDelay( CYCLE_DELAY );
 151    }
 152    NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE, 2 );
 153    osp_MicroDelay( CYCLE_DELAY );
 154    return rbyte;
 155 }
 156
 157
 158 /*
 159  * This routine will clock the Read_data function into the X2520
 160  * eeprom, followed by the address to read from, through the NicSTaR's General
 161  * Purpose register.
 162  */
 163
 164 static u_int8_t
 165 read_eprom_byte(u_int32_t base, u_int8_t offset)
 166 {
 167    u_int32_t val = 0;
 168    int i,j=0;
 169    u_int8_t tempread = 0;
 170
 171    val = NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE ) & 0xFFFFFFF0;
 172
 173    /* Send READ instruction */
 174    for (i=0; i<sizeof readtab/sizeof readtab[0]; i++)
 175    {
 176         NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 177                 (val | readtab[i]) );
 178         osp_MicroDelay( CYCLE_DELAY );
 179    }
 180
 181    /* Next, we need to send the byte address to read from */
 182    for (i=7; i>=0; i--)
 183    {
 184       NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 185                 (val | clocktab[j++] | ((offset >> i) & 1) ) );
 186       osp_MicroDelay(CYCLE_DELAY);
 187       NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 188                 (val | clocktab[j++] | ((offset >> i) & 1) ) );
 189       osp_MicroDelay( CYCLE_DELAY );
 190    }
 191
 192    j = 0;
 193
 194    /* Now, we can read data from the eeprom by clocking it in */
 195    for (i=7; i>=0; i--)
 196    {
 197       NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 198                 (val | clocktab[j++]) );
 199       osp_MicroDelay( CYCLE_DELAY );
 200       tempread |= (((NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE )
 201                 & 0x00010000) >> 16) << i);
 202       NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 203                 (val | clocktab[j++]) );
 204       osp_MicroDelay( CYCLE_DELAY );
 205    }
 206
 207    NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE, 2 );
 208    osp_MicroDelay( CYCLE_DELAY );
 209    return tempread;
 210 }
 211
 212
 213 void
 214 nicstar_init_eprom( virt_addr_t base )
 215 {
 216     u_int32_t val;
 217
 218     /*
 219      * turn chip select off
 220      */
 221     val = NICSTAR_REG_READ(base, NICSTAR_REG_GENERAL_PURPOSE) & 0xFFFFFFF0;
 222
 223     NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
 224         (val | CS_HIGH | CLK_HIGH));
 225     osp_MicroDelay( CYCLE_DELAY );
 226
 227     NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
 228         (val | CS_HIGH | CLK_LOW));
 229     osp_MicroDelay( CYCLE_DELAY );
 230
 231     NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
 232         (val | CS_HIGH | CLK_HIGH));
 233     osp_MicroDelay( CYCLE_DELAY );
 234
 235     NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
 236         (val | CS_HIGH | CLK_LOW));
 237     osp_MicroDelay( CYCLE_DELAY );
 238 }
 239
 240
 241 /*
 242  * This routine will be the interface to the ReadPromByte function
 243  * above.
 244  */
 245
 246 void
 247 nicstar_read_eprom(
 248     virt_addr_t base,
 249     u_int8_t    prom_offset,
 250     u_int8_t    *buffer,
 251     u_int32_t   nbytes )
 252 {
 253     u_int               i;
 254
 255     for (i=0; i<nbytes; i++)
 256     {
 257         buffer[i] = read_eprom_byte( base, prom_offset );
 258         ++prom_offset;
 259         osp_MicroDelay( CYCLE_DELAY );
 260     }
 261 }
 262
 263
 264 /*
 265 void osp_MicroDelay(int x) {
 266
 267 }
 268 */
 269