arch/arm/mach-imx/cpu-imx35.c

   1 /*
   2  * MX35 CPU type detection
   3  *
   4  * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11 #include <linux/module.h>
  12 #include <linux/io.h>
  13
  14 #include "hardware.h"
  15 #include "iim.h"
  16
  17 static int mx35_cpu_rev = -1;
  18
  19 static int mx35_read_cpu_rev(void)
  20 {
  21         u32 rev;
  22
  23         rev = __raw_readl(MX35_IO_ADDRESS(MX35_IIM_BASE_ADDR + MXC_IIMSREV));
  24         switch (rev) {
  25         case 0x00:
  26                 return IMX_CHIP_REVISION_1_0;
  27         case 0x10:
  28                 return IMX_CHIP_REVISION_2_0;
  29         case 0x11:
  30                 return IMX_CHIP_REVISION_2_1;
  31         default:
  32                 return IMX_CHIP_REVISION_UNKNOWN;
  33         }
  34 }
  35
  36 int mx35_revision(void)
  37 {
  38         if (mx35_cpu_rev == -1)
  39                 mx35_cpu_rev = mx35_read_cpu_rev();
  40
  41         return mx35_cpu_rev;
  42 }
  43 EXPORT_SYMBOL(mx35_revision);