linux/arch/arm/mach-omap2/clkt2xxx_apll.c

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/*
* OMAP2xxx APLL clock control functions
*
* Copyright (C) 2005-2008 Texas Instruments, Inc.
* Copyright (C) 2004-2010 Nokia Corporation
*
* Contacts:
* Richard Woodruff <r-woodruff2@ti.com>
* Paul Walmsley
*
* Based on earlier work by Tuukka Tikkanen, Tony Lindgren,
* Gordon McNutt and RidgeRun, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#undef DEBUG
#include <linux/kernel.h>
#include <linux/clk.h>
#include <linux/io.h>
#include "clock.h"
#include "clock2xxx.h"
#include "cm2xxx.h"
#include "cm-regbits-24xx.h"
/* CM_CLKEN_PLL.EN_{54,96}M_PLL options (24XX) */
#define EN_APLL_STOPPED 0
#define EN_APLL_LOCKED 3
/* CM_CLKSEL1_PLL.APLLS_CLKIN options (24XX) */
#define APLLS_CLKIN_19_2MHZ 0
#define APLLS_CLKIN_13MHZ 2
#define APLLS_CLKIN_12MHZ 3
/* Private functions */
/**
* omap2xxx_clk_apll_locked - is the APLL locked?
* @hw: struct clk_hw * of the APLL to check
*
* If the APLL IP block referred to by @hw indicates that it's locked,
* return true; otherwise, return false.
*/
static bool omap2xxx_clk_apll_locked(struct clk_hw *hw)
{
struct clk_hw_omap *clk = to_clk_hw_omap(hw);
u32 r, apll_mask;
apll_mask = EN_APLL_LOCKED << clk->enable_bit;
r = omap2xxx_cm_get_pll_status();
return ((r & apll_mask) == apll_mask) ? true : false;
}
int omap2_clk_apll96_enable(struct clk_hw *hw)
{
return omap2xxx_cm_apll96_enable();
}
int omap2_clk_apll54_enable(struct clk_hw *hw)
{
return omap2xxx_cm_apll54_enable();
}
static void _apll96_allow_idle(struct clk_hw_omap *clk)
{
omap2xxx_cm_set_apll96_auto_low_power_stop();
}
static void _apll96_deny_idle(struct clk_hw_omap *clk)
{
omap2xxx_cm_set_apll96_disable_autoidle();
}
static void _apll54_allow_idle(struct clk_hw_omap *clk)
{
omap2xxx_cm_set_apll54_auto_low_power_stop();
}
static void _apll54_deny_idle(struct clk_hw_omap *clk)
{
omap2xxx_cm_set_apll54_disable_autoidle();
}
void omap2_clk_apll96_disable(struct clk_hw *hw)
{
omap2xxx_cm_apll96_disable();
}
void omap2_clk_apll54_disable(struct clk_hw *hw)
{
omap2xxx_cm_apll54_disable();
}
unsigned long omap2_clk_apll54_recalc(struct clk_hw *hw,
unsigned long parent_rate)
{
return (omap2xxx_clk_apll_locked(hw)) ? 54000000 : 0;
}
unsigned long omap2_clk_apll96_recalc(struct clk_hw *hw,
unsigned long parent_rate)
{
return (omap2xxx_clk_apll_locked(hw)) ? 96000000 : 0;
}
/* Public data */
const struct clk_hw_omap_ops clkhwops_apll54 = {
.allow_idle = _apll54_allow_idle,
.deny_idle = _apll54_deny_idle,
};
const struct clk_hw_omap_ops clkhwops_apll96 = {
.allow_idle = _apll96_allow_idle,
.deny_idle = _apll96_deny_idle,
};
/* Public functions */
u32 omap2xxx_get_apll_clkin(void)
{
u32 aplls, srate = 0;
aplls = omap2xxx_cm_get_pll_config();
aplls &= OMAP24XX_APLLS_CLKIN_MASK;
aplls >>= OMAP24XX_APLLS_CLKIN_SHIFT;
if (aplls == APLLS_CLKIN_19_2MHZ)
srate = 19200000;
else if (aplls == APLLS_CLKIN_13MHZ)
srate = 13000000;
else if (aplls == APLLS_CLKIN_12MHZ)
srate = 12000000;
return srate;
}