arch/arm/mach-imx/cpu-imx25.c

   1 /*
   2  * MX25 CPU type detection
   3  *
   4  * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
   5  * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  */
  12 #include <linux/module.h>
  13 #include <linux/io.h>
  14 #include <mach/hardware.h>
  15 #include <mach/iim.h>
  16
  17 static int mx25_cpu_rev = -1;
  18
  19 static int mx25_read_cpu_rev(void)
  20 {
  21         u32 rev;
  22
  23         rev = __raw_readl(MX25_IO_ADDRESS(MX25_IIM_BASE_ADDR + MXC_IIMSREV));
  24         switch (rev) {
  25         case 0x00:
  26                 return IMX_CHIP_REVISION_1_0;
  27         case 0x01:
  28                 return IMX_CHIP_REVISION_1_1;
  29         default:
  30                 return IMX_CHIP_REVISION_UNKNOWN;
  31         }
  32 }
  33
  34 int mx25_revision(void)
  35 {
  36         if (mx25_cpu_rev == -1)
  37                 mx25_cpu_rev = mx25_read_cpu_rev();
  38
  39         return mx25_cpu_rev;
  40 }
  41 EXPORT_SYMBOL(mx25_revision);