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 typedef void __iomem *virt_addr_t;
  11
  12 #define CYCLE_DELAY 5
  13
  14 /* This was the original definition
  15 #define osp_MicroDelay(microsec) \
  16     do { int _i = 4*microsec; while (--_i > 0) { __SLOW_DOWN_IO; }} while (0)
  17 */
  18 #define osp_MicroDelay(microsec) {unsigned long useconds = (microsec); \
  19                                   udelay((useconds));}
  20
  21
  22 /* The following tables represent the timing diagrams found in
  23  * the Data Sheet for the Xicor X25020 EEProm.  The #defines below
  24  * represent the bits in the NICStAR's General Purpose register
  25  * that must be toggled for the corresponding actions on the EEProm
  26  * to occur.
  27  */
  28
  29 /* Write Data To EEProm from SI line on rising edge of CLK */
  30 /* Read Data From EEProm on falling edge of CLK */
  31
  32 #define CS_HIGH         0x0002          /* Chip select high */
  33 #define CS_LOW          0x0000          /* Chip select low (active low)*/
  34 #define CLK_HIGH        0x0004          /* Clock high */
  35 #define CLK_LOW         0x0000          /* Clock low  */
  36 #define SI_HIGH         0x0001          /* Serial input data high */
  37 #define SI_LOW          0x0000          /* Serial input data low */
  38
  39 /* Read Status Register = 0000 0101b */
  40 #if 0
  41 static u_int32_t rdsrtab[] =
  42 {
  43     CS_HIGH | CLK_HIGH,
  44     CS_LOW | CLK_LOW,
  45     CLK_HIGH,             /* 0 */
  46     CLK_LOW,
  47     CLK_HIGH,             /* 0 */
  48     CLK_LOW,
  49     CLK_HIGH,             /* 0 */
  50     CLK_LOW,
  51     CLK_HIGH,             /* 0 */
  52     CLK_LOW,
  53     CLK_HIGH,             /* 0 */
  54     CLK_LOW | SI_HIGH,
  55     CLK_HIGH | SI_HIGH,   /* 1 */
  56     CLK_LOW | SI_LOW,
  57     CLK_HIGH,             /* 0 */
  58     CLK_LOW | SI_HIGH,
  59     CLK_HIGH | SI_HIGH   /* 1 */
  60 };
  61 #endif  /*  0  */
  62
  63
  64 /* Read from EEPROM = 0000 0011b */
  65 static u_int32_t readtab[] =
  66 {
  67     /*
  68     CS_HIGH | CLK_HIGH,
  69     */
  70     CS_LOW | 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,
  79     CLK_HIGH,             /* 0 */
  80     CLK_LOW,
  81     CLK_HIGH,             /* 0 */
  82     CLK_LOW | SI_HIGH,
  83     CLK_HIGH | SI_HIGH,   /* 1 */
  84     CLK_LOW | SI_HIGH,
  85     CLK_HIGH | SI_HIGH    /* 1 */
  86 };
  87
  88
  89 /* Clock to read from/write to the eeprom */
  90 static u_int32_t clocktab[] =
  91 {
  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     CLK_HIGH,
 106     CLK_LOW,
 107     CLK_HIGH,
 108     CLK_LOW
 109 };
 110
 111
 112 #define NICSTAR_REG_WRITE(bs, reg, val) \
 113         while ( readl(bs + STAT) & 0x0200 ) ; \
 114         writel((val),(base)+(reg))
 115 #define NICSTAR_REG_READ(bs, reg) \
 116         readl((base)+(reg))
 117 #define NICSTAR_REG_GENERAL_PURPOSE GP
 118
 119 /*
 120  * This routine will clock the Read_Status_reg function into the X2520
 121  * eeprom, then pull the result from bit 16 of the NicSTaR's General Purpose
 122  * register.
 123  */
 124 #if 0
 125 u_int32_t
 126 nicstar_read_eprom_status( virt_addr_t base )
 127 {
 128    u_int32_t    val;
 129    u_int32_t    rbyte;
 130    int32_t      i, j;
 131
 132    /* Send read instruction */
 133    val = NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE ) & 0xFFFFFFF0;
 134
 135    for (i=0; i<sizeof rdsrtab/sizeof rdsrtab[0]; i++)
 136    {
 137         NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 138                 (val | rdsrtab[i]) );
 139         osp_MicroDelay( CYCLE_DELAY );
 140    }
 141
 142    /* Done sending instruction - now pull data off of bit 16, MSB first */
 143    /* Data clocked out of eeprom on falling edge of clock */
 144
 145    rbyte = 0;
 146    for (i=7, j=0; i>=0; i--)
 147    {
 148         NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 149                 (val | clocktab[j++]) );
 150         rbyte |= (((NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE)
 151                         & 0x00010000) >> 16) << i);
 152         NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 153                 (val | clocktab[j++]) );
 154         osp_MicroDelay( CYCLE_DELAY );
 155    }
 156    NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE, 2 );
 157    osp_MicroDelay( CYCLE_DELAY );
 158    return rbyte;
 159 }
 160 #endif  /*  0  */
 161
 162
 163 /*
 164  * This routine will clock the Read_data function into the X2520
 165  * eeprom, followed by the address to read from, through the NicSTaR's General
 166  * Purpose register.
 167  */
 168
 169 static u_int8_t
 170 read_eprom_byte(virt_addr_t base, u_int8_t offset)
 171 {
 172    u_int32_t val = 0;
 173    int i,j=0;
 174    u_int8_t tempread = 0;
 175
 176    val = NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE ) & 0xFFFFFFF0;
 177
 178    /* Send READ instruction */
 179    for (i=0; i<sizeof readtab/sizeof readtab[0]; i++)
 180    {
 181         NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 182                 (val | readtab[i]) );
 183         osp_MicroDelay( CYCLE_DELAY );
 184    }
 185
 186    /* Next, we need to send the byte address to read from */
 187    for (i=7; i>=0; i--)
 188    {
 189       NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 190                 (val | clocktab[j++] | ((offset >> i) & 1) ) );
 191       osp_MicroDelay(CYCLE_DELAY);
 192       NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 193                 (val | clocktab[j++] | ((offset >> i) & 1) ) );
 194       osp_MicroDelay( CYCLE_DELAY );
 195    }
 196
 197    j = 0;
 198
 199    /* Now, we can read data from the eeprom by clocking it in */
 200    for (i=7; i>=0; i--)
 201    {
 202       NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 203                 (val | clocktab[j++]) );
 204       osp_MicroDelay( CYCLE_DELAY );
 205       tempread |= (((NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE )
 206                 & 0x00010000) >> 16) << i);
 207       NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 208                 (val | clocktab[j++]) );
 209       osp_MicroDelay( CYCLE_DELAY );
 210    }
 211
 212    NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE, 2 );
 213    osp_MicroDelay( CYCLE_DELAY );
 214    return tempread;
 215 }
 216
 217
 218 static void
 219 nicstar_init_eprom( virt_addr_t base )
 220 {
 221     u_int32_t val;
 222
 223     /*
 224      * turn chip select off
 225      */
 226     val = NICSTAR_REG_READ(base, NICSTAR_REG_GENERAL_PURPOSE) & 0xFFFFFFF0;
 227
 228     NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
 229         (val | CS_HIGH | CLK_HIGH));
 230     osp_MicroDelay( CYCLE_DELAY );
 231
 232     NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
 233         (val | CS_HIGH | CLK_LOW));
 234     osp_MicroDelay( CYCLE_DELAY );
 235
 236     NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
 237         (val | CS_HIGH | CLK_HIGH));
 238     osp_MicroDelay( CYCLE_DELAY );
 239
 240     NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
 241         (val | CS_HIGH | CLK_LOW));
 242     osp_MicroDelay( CYCLE_DELAY );
 243 }
 244
 245
 246 /*
 247  * This routine will be the interface to the ReadPromByte function
 248  * above.
 249  */
 250
 251 static void
 252 nicstar_read_eprom(
 253     virt_addr_t base,
 254     u_int8_t    prom_offset,
 255     u_int8_t    *buffer,
 256     u_int32_t   nbytes )
 257 {
 258     u_int               i;
 259
 260     for (i=0; i<nbytes; i++)
 261     {
 262         buffer[i] = read_eprom_byte( base, prom_offset );
 263         ++prom_offset;
 264         osp_MicroDelay( CYCLE_DELAY );
 265     }
 266 }
 267
 268
 269 /*
 270 void osp_MicroDelay(int x) {
 271
 272 }
 273 */
 274