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 #include <mach/hardware.h>
  14 #include <mach/iim.h>
  15
  16 static int mx35_cpu_rev = -1;
  17
  18 static int mx35_read_cpu_rev(void)
  19 {
  20         u32 rev;
  21
  22         rev = __raw_readl(MX35_IO_ADDRESS(MX35_IIM_BASE_ADDR + MXC_IIMSREV));
  23         switch (rev) {
  24         case 0x00:
  25                 return IMX_CHIP_REVISION_1_0;
  26         case 0x10:
  27                 return IMX_CHIP_REVISION_2_0;
  28         case 0x11:
  29                 return IMX_CHIP_REVISION_2_1;
  30         default:
  31                 return IMX_CHIP_REVISION_UNKNOWN;
  32         }
  33 }
  34
  35 int mx35_revision(void)
  36 {
  37         if (mx35_cpu_rev == -1)
  38                 mx35_cpu_rev = mx35_read_cpu_rev();
  39
  40         return mx35_cpu_rev;
  41 }
  42 EXPORT_SYMBOL(mx35_revision);