kernel/genarch/include/drivers/am335x/ctrl_module.h

   1 /*
   2  * Copyright (c) 2013 Maurizio Lombardi
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * - Redistributions of source code must retain the above copyright
  10  *   notice, this list of conditions and the following disclaimer.
  11  * - Redistributions in binary form must reproduce the above copyright
  12  *   notice, this list of conditions and the following disclaimer in the
  13  *   documentation and/or other materials provided with the distribution.
  14  * - The name of the author may not be used to endorse or promote products
  15  *   derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28 /** @addtogroup genarch
  29  * @{
  30  */
  31 /**
  32  * @file
  33  * @brief Texas Instruments AM335x control module.
  34  */
  35
  36 #ifndef _KERN_AM335X_CTRL_MODULE_H_
  37 #define _KERN_AM335X_CTRL_MODULE_H_
  38
  39 #include <errno.h>
  40 #include <typedefs.h>
  41 #include "ctrl_module_regs.h"
  42
  43 #define AM335x_CTRL_MODULE_BASE_ADDRESS  0x44E10000
  44 #define AM335x_CTRL_MODULE_SIZE          131072 /* 128 Kb */
  45
  46 typedef ioport32_t am335x_ctrl_module_t;
  47
  48 static int
  49 am335x_ctrl_module_clock_freq_get(am335x_ctrl_module_t *base, unsigned *freq)
  50 {
  51         unsigned const control_status = AM335x_CTRL_MODULE_REG_VALUE(base,
  52             CONTROL_STATUS);
  53
  54         /* Get the sysboot1 field at control_status[22,23] */
  55         unsigned const sysboot1 = (control_status >> 22) & 0x03;
  56
  57         switch (sysboot1) {
  58         default:
  59                 return EINVAL;
  60         case 0:
  61                 *freq = 19200000; /* 19.2 Mhz */
  62                 break;
  63         case 1:
  64                 *freq = 24000000; /* 24 Mhz */
  65                 break;
  66         case 2:
  67                 *freq = 25000000; /* 25 Mhz */
  68                 break;
  69         case 3:
  70                 *freq = 26000000; /* 26 Mhz */
  71                 break;
  72         }
  73
  74         return EOK;
  75 }
  76
  77 #endif
  78
  79 /**
  80  * @}
  81  */