drivers/net/wan/8253x/amcc5920.c

   1 /* -*- linux-c -*- */
   2 /*
   3  * Copyright (C) 2001 By Joachim Martillo, Telford Tools, Inc.
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License
   7  * as published by the Free Software Foundation; either version
   8  * 2 of the License, or (at your option) any later version.
   9  *
  10  */
  11                                 /* This file is linked in, but I am
  12                                    not sure there is ever any
  13                                    reason directly to read the
  14                                    serial eprom on the multichannel
  15                                    server host card. */
  16
  17 /* We handle PCI devices */
  18 #include <linux/pci.h>
  19
  20 /* We need to use ioremap */
  21 #include <asm/io.h>
  22
  23 #include <linux/delay.h>
  24
  25 #include "8253xmcs.h"
  26 #include "8253xctl.h"
  27
  28 /* read a byte out of the serial eeprom/nvram by means of
  29  * 16 short commands */
  30
  31 static unsigned int amcc_nvram_breadw(unsigned char *bridge_space,
  32                                       unsigned short address,
  33                                       unsigned char *value)
  34 {
  35         unsigned int count;
  36         unsigned rhr;
  37
  38         for(count = 0; count < 20000; ++count)
  39         {
  40                 rhr = readl(bridge_space + AMCC_RCR);
  41                 if((rhr & AMCC_NVRBUSY) == 0)
  42                 {
  43                         break;
  44                 }
  45                 udelay(1);
  46         }
  47         if(count >= 20000)
  48         {
  49                 return FALSE;
  50         }
  51         rhr = AMCC_NVRWRLA | ((address & 0x00FF) << 16);
  52         writel(rhr, bridge_space + AMCC_RCR);
  53         rhr = AMCC_NVRWRHA | ((address & 0xFF00) << 8);
  54         writel(rhr, bridge_space + AMCC_RCR);
  55         writel(AMCC_NVRRDDB, bridge_space + AMCC_RCR);
  56         for(count = 0; count < 20000; ++count)
  57         {
  58                 rhr = readl(bridge_space + AMCC_RCR);
  59                 if((rhr & AMCC_NVRBUSY) == 0)
  60                 {
  61                         break;
  62                 }
  63                 udelay(1);
  64         }
  65         if(count >= 20000)
  66         {
  67                 return FALSE;
  68         }
  69         if(rhr & AMCC_NVRACCFAIL)
  70         {
  71                 return FALSE;
  72         }
  73         *value = (unsigned char) (rhr >> 16);
  74         return TRUE;
  75 }
  76
  77 /* read the whole serial eeprom from the host card */
  78
  79 unsigned int amcc_read_nvram(unsigned char* buffer, unsigned length, unsigned char *bridge_space)
  80 {
  81         unsigned int count;
  82         length <<= 1;                   /* covert words to bytes */
  83
  84         for(count = 0; count < length; ++count)
  85         {
  86                 if(amcc_nvram_breadw(bridge_space, count, &buffer[count]) == FALSE)
  87                 {
  88                         return FALSE;
  89                 }
  90         }
  91         return TRUE;
  92 }