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 #include <linux/kernel.h>
  11
  12 typedef void __iomem *virt_addr_t;
  13
  14 #define CYCLE_DELAY 5
  15
  16 /* This was the original definition
  17 #define osp_MicroDelay(microsec) \
  18     do { int _i = 4*microsec; while (--_i > 0) { __SLOW_DOWN_IO; }} while (0)
  19 */
  20 #define osp_MicroDelay(microsec) {unsigned long useconds = (microsec); \
  21                                   udelay((useconds));}
  22
  23
  24 /* The following tables represent the timing diagrams found in
  25  * the Data Sheet for the Xicor X25020 EEProm.  The #defines below
  26  * represent the bits in the NICStAR's General Purpose register
  27  * that must be toggled for the corresponding actions on the EEProm
  28  * to occur.
  29  */
  30
  31 /* Write Data To EEProm from SI line on rising edge of CLK */
  32 /* Read Data From EEProm on falling edge of CLK */
  33
  34 #define CS_HIGH         0x0002          /* Chip select high */
  35 #define CS_LOW          0x0000          /* Chip select low (active low)*/
  36 #define CLK_HIGH        0x0004          /* Clock high */
  37 #define CLK_LOW         0x0000          /* Clock low  */
  38 #define SI_HIGH         0x0001          /* Serial input data high */
  39 #define SI_LOW          0x0000          /* Serial input data low */
  40
  41 /* Read Status Register = 0000 0101b */
  42 #if 0
  43 static u_int32_t rdsrtab[] =
  44 {
  45     CS_HIGH | CLK_HIGH,
  46     CS_LOW | 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,
  55     CLK_HIGH,             /* 0 */
  56     CLK_LOW | SI_HIGH,
  57     CLK_HIGH | SI_HIGH,   /* 1 */
  58     CLK_LOW | SI_LOW,
  59     CLK_HIGH,             /* 0 */
  60     CLK_LOW | SI_HIGH,
  61     CLK_HIGH | SI_HIGH   /* 1 */
  62 };
  63 #endif  /*  0  */
  64
  65
  66 /* Read from EEPROM = 0000 0011b */
  67 static u_int32_t readtab[] =
  68 {
  69     /*
  70     CS_HIGH | CLK_HIGH,
  71     */
  72     CS_LOW | 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,
  83     CLK_HIGH,             /* 0 */
  84     CLK_LOW | SI_HIGH,
  85     CLK_HIGH | SI_HIGH,   /* 1 */
  86     CLK_LOW | SI_HIGH,
  87     CLK_HIGH | SI_HIGH    /* 1 */
  88 };
  89
  90
  91 /* Clock to read from/write to the eeprom */
  92 static u_int32_t clocktab[] =
  93 {
  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     CLK_HIGH,
 110     CLK_LOW
 111 };
 112
 113
 114 #define NICSTAR_REG_WRITE(bs, reg, val) \
 115         while ( readl(bs + STAT) & 0x0200 ) ; \
 116         writel((val),(base)+(reg))
 117 #define NICSTAR_REG_READ(bs, reg) \
 118         readl((base)+(reg))
 119 #define NICSTAR_REG_GENERAL_PURPOSE GP
 120
 121 /*
 122  * This routine will clock the Read_Status_reg function into the X2520
 123  * eeprom, then pull the result from bit 16 of the NicSTaR's General Purpose
 124  * register.
 125  */
 126 #if 0
 127 u_int32_t
 128 nicstar_read_eprom_status( virt_addr_t base )
 129 {
 130    u_int32_t    val;
 131    u_int32_t    rbyte;
 132    int32_t      i, j;
 133
 134    /* Send read instruction */
 135    val = NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE ) & 0xFFFFFFF0;
 136
 137    for (i=0; i<ARRAY_SIZE(rdsrtab); i++)
 138    {
 139         NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 140                 (val | rdsrtab[i]) );
 141         osp_MicroDelay( CYCLE_DELAY );
 142    }
 143
 144    /* Done sending instruction - now pull data off of bit 16, MSB first */
 145    /* Data clocked out of eeprom on falling edge of clock */
 146
 147    rbyte = 0;
 148    for (i=7, j=0; i>=0; i--)
 149    {
 150         NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 151                 (val | clocktab[j++]) );
 152         rbyte |= (((NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE)
 153                         & 0x00010000) >> 16) << i);
 154         NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 155                 (val | clocktab[j++]) );
 156         osp_MicroDelay( CYCLE_DELAY );
 157    }
 158    NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE, 2 );
 159    osp_MicroDelay( CYCLE_DELAY );
 160    return rbyte;
 161 }
 162 #endif  /*  0  */
 163
 164
 165 /*
 166  * This routine will clock the Read_data function into the X2520
 167  * eeprom, followed by the address to read from, through the NicSTaR's General
 168  * Purpose register.
 169  */
 170
 171 static u_int8_t
 172 read_eprom_byte(virt_addr_t base, u_int8_t offset)
 173 {
 174    u_int32_t val = 0;
 175    int i,j=0;
 176    u_int8_t tempread = 0;
 177
 178    val = NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE ) & 0xFFFFFFF0;
 179
 180    /* Send READ instruction */
 181    for (i=0; i<ARRAY_SIZE(readtab); i++)
 182    {
 183         NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 184                 (val | readtab[i]) );
 185         osp_MicroDelay( CYCLE_DELAY );
 186    }
 187
 188    /* Next, we need to send the byte address to read from */
 189    for (i=7; i>=0; i--)
 190    {
 191       NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 192                 (val | clocktab[j++] | ((offset >> i) & 1) ) );
 193       osp_MicroDelay(CYCLE_DELAY);
 194       NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 195                 (val | clocktab[j++] | ((offset >> i) & 1) ) );
 196       osp_MicroDelay( CYCLE_DELAY );
 197    }
 198
 199    j = 0;
 200
 201    /* Now, we can read data from the eeprom by clocking it in */
 202    for (i=7; i>=0; i--)
 203    {
 204       NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 205                 (val | clocktab[j++]) );
 206       osp_MicroDelay( CYCLE_DELAY );
 207       tempread |= (((NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE )
 208                 & 0x00010000) >> 16) << i);
 209       NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
 210                 (val | clocktab[j++]) );
 211       osp_MicroDelay( CYCLE_DELAY );
 212    }
 213
 214    NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE, 2 );
 215    osp_MicroDelay( CYCLE_DELAY );
 216    return tempread;
 217 }
 218
 219
 220 static void
 221 nicstar_init_eprom( virt_addr_t base )
 222 {
 223     u_int32_t val;
 224
 225     /*
 226      * turn chip select off
 227      */
 228     val = NICSTAR_REG_READ(base, NICSTAR_REG_GENERAL_PURPOSE) & 0xFFFFFFF0;
 229
 230     NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
 231         (val | CS_HIGH | CLK_HIGH));
 232     osp_MicroDelay( CYCLE_DELAY );
 233
 234     NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
 235         (val | CS_HIGH | CLK_LOW));
 236     osp_MicroDelay( CYCLE_DELAY );
 237
 238     NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
 239         (val | CS_HIGH | CLK_HIGH));
 240     osp_MicroDelay( CYCLE_DELAY );
 241
 242     NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
 243         (val | CS_HIGH | CLK_LOW));
 244     osp_MicroDelay( CYCLE_DELAY );
 245 }
 246
 247
 248 /*
 249  * This routine will be the interface to the ReadPromByte function
 250  * above.
 251  */
 252
 253 static void
 254 nicstar_read_eprom(
 255     virt_addr_t base,
 256     u_int8_t    prom_offset,
 257     u_int8_t    *buffer,
 258     u_int32_t   nbytes )
 259 {
 260     u_int               i;
 261
 262     for (i=0; i<nbytes; i++)
 263     {
 264         buffer[i] = read_eprom_byte( base, prom_offset );
 265         ++prom_offset;
 266         osp_MicroDelay( CYCLE_DELAY );
 267     }
 268 }
 269
 270
 271 /*
 272 void osp_MicroDelay(int x) {
 273
 274 }
 275 */
 276