arch/arm/mach-omap2/dpll44xx.c

   1 /*
   2  * OMAP4-specific DPLL control functions
   3  *
   4  * Copyright (C) 2011 Texas Instruments, Inc.
   5  * Rajendra Nayak
   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 version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/errno.h>
  14 #include <linux/clk.h>
  15 #include <linux/io.h>
  16 #include <linux/bitops.h>
  17
  18 #include <plat/cpu.h>
  19 #include <plat/clock.h>
  20
  21 #include "clock.h"
  22 #include "cm-regbits-44xx.h"
  23
  24 /* Supported only on OMAP4 */
  25 int omap4_dpllmx_gatectrl_read(struct clk *clk)
  26 {
  27         u32 v;
  28         u32 mask;
  29
  30         if (!clk || !clk->clksel_reg || !cpu_is_omap44xx())
  31                 return -EINVAL;
  32
  33         mask = clk->flags & CLOCK_CLKOUTX2 ?
  34                         OMAP4430_DPLL_CLKOUTX2_GATE_CTRL_MASK :
  35                         OMAP4430_DPLL_CLKOUT_GATE_CTRL_MASK;
  36
  37         v = __raw_readl(clk->clksel_reg);
  38         v &= mask;
  39         v >>= __ffs(mask);
  40
  41         return v;
  42 }
  43
  44 void omap4_dpllmx_allow_gatectrl(struct clk *clk)
  45 {
  46         u32 v;
  47         u32 mask;
  48
  49         if (!clk || !clk->clksel_reg || !cpu_is_omap44xx())
  50                 return;
  51
  52         mask = clk->flags & CLOCK_CLKOUTX2 ?
  53                         OMAP4430_DPLL_CLKOUTX2_GATE_CTRL_MASK :
  54                         OMAP4430_DPLL_CLKOUT_GATE_CTRL_MASK;
  55
  56         v = __raw_readl(clk->clksel_reg);
  57         /* Clear the bit to allow gatectrl */
  58         v &= ~mask;
  59         __raw_writel(v, clk->clksel_reg);
  60 }
  61
  62 void omap4_dpllmx_deny_gatectrl(struct clk *clk)
  63 {
  64         u32 v;
  65         u32 mask;
  66
  67         if (!clk || !clk->clksel_reg || !cpu_is_omap44xx())
  68                 return;
  69
  70         mask = clk->flags & CLOCK_CLKOUTX2 ?
  71                         OMAP4430_DPLL_CLKOUTX2_GATE_CTRL_MASK :
  72                         OMAP4430_DPLL_CLKOUT_GATE_CTRL_MASK;
  73
  74         v = __raw_readl(clk->clksel_reg);
  75         /* Set the bit to deny gatectrl */
  76         v |= mask;
  77         __raw_writel(v, clk->clksel_reg);
  78 }
  79
  80 const struct clkops clkops_omap4_dpllmx_ops = {
  81         .allow_idle     = omap4_dpllmx_allow_gatectrl,
  82         .deny_idle      = omap4_dpllmx_deny_gatectrl,
  83 };
  84