release/src-rt-6.x.4708/linux/linux-2.6.36/arch/arm/mach-omap2/clkt2xxx_sys.c

   1 /*
   2  * OMAP2xxx sys_clk-specific clock code
   3  *
   4  * Copyright (C) 2005-2008 Texas Instruments, Inc.
   5  * Copyright (C) 2004-2010 Nokia Corporation
   6  *
   7  * Contacts:
   8  * Richard Woodruff <r-woodruff2@ti.com>
   9  * Paul Walmsley
  10  *
  11  * Based on earlier work by Tuukka Tikkanen, Tony Lindgren,
  12  * Gordon McNutt and RidgeRun, Inc.
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License version 2 as
  16  * published by the Free Software Foundation.
  17  */
  18 #undef DEBUG
  19
  20 #include <linux/kernel.h>
  21 #include <linux/errno.h>
  22 #include <linux/clk.h>
  23 #include <linux/io.h>
  24
  25 #include <plat/clock.h>
  26
  27 #include "clock.h"
  28 #include "clock2xxx.h"
  29 #include "prm.h"
  30 #include "prm-regbits-24xx.h"
  31
  32 void __iomem *prcm_clksrc_ctrl;
  33
  34 u32 omap2xxx_get_sysclkdiv(void)
  35 {
  36         u32 div;
  37
  38         div = __raw_readl(prcm_clksrc_ctrl);
  39         div &= OMAP_SYSCLKDIV_MASK;
  40         div >>= OMAP_SYSCLKDIV_SHIFT;
  41
  42         return div;
  43 }
  44
  45 unsigned long omap2xxx_sys_clk_recalc(struct clk *clk)
  46 {
  47         return clk->parent->rate / omap2xxx_get_sysclkdiv();
  48 }