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
  15 #include "iim.h"
  16 #include "hardware.h"
  17
  18 static int mx25_cpu_rev = -1;
  19
  20 static int mx25_read_cpu_rev(void)
  21 {
  22         u32 rev;
  23
  24         rev = __raw_readl(MX25_IO_ADDRESS(MX25_IIM_BASE_ADDR + MXC_IIMSREV));
  25         switch (rev) {
  26         case 0x00:
  27                 return IMX_CHIP_REVISION_1_0;
  28         case 0x01:
  29                 return IMX_CHIP_REVISION_1_1;
  30         default:
  31                 return IMX_CHIP_REVISION_UNKNOWN;
  32         }
  33 }
  34
  35 int mx25_revision(void)
  36 {
  37         if (mx25_cpu_rev == -1)
  38                 mx25_cpu_rev = mx25_read_cpu_rev();
  39
  40         return mx25_cpu_rev;
  41 }
  42 EXPORT_SYMBOL(mx25_revision);