linux/arch/arm/mach-omap2/clock34xx.c

/*
 * OMAP3-specific clock framework functions
 *
 * Copyright (C) 2007-2008 Texas Instruments, Inc.
 * Copyright (C) 2007-2009 Nokia Corporation
 *
 * Written by Paul Walmsley
 * Testing and integration fixes by Jouni Högander
 *
 * Parts of this code are based on code written by
 * Richard Woodruff, Tony Lindgren, Tuukka Tikkanen, Karthik Dasu
 *
 * 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/module.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/limits.h>
#include <linux/bitops.h>

#include <plat/cpu.h>
#include <plat/clock.h>
#include <plat/sram.h>
#include <plat/sdrc.h>
#include <asm/div64.h>
#include <asm/clkdev.h>

#include <plat/sdrc.h>
#include "clock.h"
#include "clock34xx.h"
#include "sdrc.h"
#include "prm.h"
#include "prm-regbits-34xx.h"
#include "cm.h"
#include "cm-regbits-34xx.h"

/* CM_AUTOIDLE_PLL*.AUTO_* bit values */
#define DPLL_AUTOIDLE_DISABLE			0x0
#define DPLL_AUTOIDLE_LOW_POWER_STOP		0x1

#define MAX_DPLL_WAIT_TRIES		1000000

#define CYCLES_PER_MHZ			1000000

/*
 * DPLL5_FREQ_FOR_USBHOST: USBHOST and USBTLL are the only clocks
 * that are sourced by DPLL5, and both of these require this clock
 * to be at 120 MHz for proper operation.
 */
#define DPLL5_FREQ_FOR_USBHOST		120000000

/* needed by omap3_core_dpll_m2_set_rate() */
struct clk *sdrc_ick_p, *arm_fck_p;

/**
 * omap3430es2_clk_ssi_find_idlest - return CM_IDLEST info for SSI
 * @clk: struct clk * being enabled
 * @idlest_reg: void __iomem ** to store CM_IDLEST reg address into
 * @idlest_bit: pointer to a u8 to store the CM_IDLEST bit shift into
 *
 * The OMAP3430ES2 SSI target CM_IDLEST bit is at a different shift
 * from the CM_{I,F}CLKEN bit.  Pass back the correct info via
 * @idlest_reg and @idlest_bit.  No return value.
 */
static void omap3430es2_clk_ssi_find_idlest(struct clk *clk,
					    void __iomem **idlest_reg,
					    u8 *idlest_bit)
{
	u32 r;

	r = (((__force u32)clk->enable_reg & ~0xf0) | 0x20);
	*idlest_reg = (__force void __iomem *)r;
	*idlest_bit = OMAP3430ES2_ST_SSI_IDLE_SHIFT;
}

const struct clkops clkops_omap3430es2_ssi_wait = {
	.enable		= omap2_dflt_clk_enable,
	.disable	= omap2_dflt_clk_disable,
	.find_idlest	= omap3430es2_clk_ssi_find_idlest,
	.find_companion = omap2_clk_dflt_find_companion,
};

/**
 * omap3430es2_clk_dss_usbhost_find_idlest - CM_IDLEST info for DSS, USBHOST
 * @clk: struct clk * being enabled
 * @idlest_reg: void __iomem ** to store CM_IDLEST reg address into
 * @idlest_bit: pointer to a u8 to store the CM_IDLEST bit shift into
 *
 * Some OMAP modules on OMAP3 ES2+ chips have both initiator and
 * target IDLEST bits.  For our purposes, we are concerned with the
 * target IDLEST bits, which exist at a different bit position than
 * the *CLKEN bit position for these modules (DSS and USBHOST) (The
 * default find_idlest code assumes that they are at the same
 * position.)  No return value.
 */
static void omap3430es2_clk_dss_usbhost_find_idlest(struct clk *clk,
						    void __iomem **idlest_reg,
						    u8 *idlest_bit)
{
	u32 r;

	r = (((__force u32)clk->enable_reg & ~0xf0) | 0x20);
	*idlest_reg = (__force void __iomem *)r;
	/* USBHOST_IDLE has same shift */
	*idlest_bit = OMAP3430ES2_ST_DSS_IDLE_SHIFT;
}

const struct clkops clkops_omap3430es2_dss_usbhost_wait = {
	.enable		= omap2_dflt_clk_enable,
	.disable	= omap2_dflt_clk_disable,
	.find_idlest	= omap3430es2_clk_dss_usbhost_find_idlest,
	.find_companion = omap2_clk_dflt_find_companion,
};

/**
 * omap3430es2_clk_hsotgusb_find_idlest - return CM_IDLEST info for HSOTGUSB
 * @clk: struct clk * being enabled
 * @idlest_reg: void __iomem ** to store CM_IDLEST reg address into
 * @idlest_bit: pointer to a u8 to store the CM_IDLEST bit shift into
 *
 * The OMAP3430ES2 HSOTGUSB target CM_IDLEST bit is at a different
 * shift from the CM_{I,F}CLKEN bit.  Pass back the correct info via
 * @idlest_reg and @idlest_bit.  No return value.
 */
static void omap3430es2_clk_hsotgusb_find_idlest(struct clk *clk,
						 void __iomem **idlest_reg,
						 u8 *idlest_bit)
{
	u32 r;

	r = (((__force u32)clk->enable_reg & ~0xf0) | 0x20);
	*idlest_reg = (__force void __iomem *)r;
	*idlest_bit = OMAP3430ES2_ST_HSOTGUSB_IDLE_SHIFT;
}

const struct clkops clkops_omap3430es2_hsotgusb_wait = {
	.enable		= omap2_dflt_clk_enable,
	.disable	= omap2_dflt_clk_disable,
	.find_idlest	= omap3430es2_clk_hsotgusb_find_idlest,
	.find_companion = omap2_clk_dflt_find_companion,
};

/**
 * omap3_dpll_recalc - recalculate DPLL rate
 * @clk: DPLL struct clk
 *
 * Recalculate and propagate the DPLL rate.
 */
unsigned long omap3_dpll_recalc(struct clk *clk)
{
	return omap2_get_dpll_rate(clk);
}

/* _omap3_dpll_write_clken - write clken_bits arg to a DPLL's enable bits */
static void _omap3_dpll_write_clken(struct clk *clk, u8 clken_bits)
{
	const struct dpll_data *dd;
	u32 v;

	dd = clk->dpll_data;

	v = __raw_readl(dd->control_reg);
	v &= ~dd->enable_mask;
	v |= clken_bits << __ffs(dd->enable_mask);
	__raw_writel(v, dd->control_reg);
}

/* _omap3_wait_dpll_status: wait for a DPLL to enter a specific state */
static int _omap3_wait_dpll_status(struct clk *clk, u8 state)
{
	const struct dpll_data *dd;
	int i = 0;
	int ret = -EINVAL;

	dd = clk->dpll_data;

	state <<= __ffs(dd->idlest_mask);

	while (((__raw_readl(dd->idlest_reg) & dd->idlest_mask) != state) &&
	       i < MAX_DPLL_WAIT_TRIES) {
		i++;
		udelay(1);
	}

	if (i == MAX_DPLL_WAIT_TRIES) {
		printk(KERN_ERR "clock: %s failed transition to '%s'\n",
		       clk->name, (state) ? "locked" : "bypassed");
	} else {
		pr_debug("clock: %s transition to '%s' in %d loops\n",
			 clk->name, (state) ? "locked" : "bypassed", i);

		ret = 0;
	}

	return ret;
}

/* From 3430 TRM ES2 4.7.6.2 */
static u16 _omap3_dpll_compute_freqsel(struct clk *clk, u8 n)
{
	unsigned long fint;
	u16 f = 0;

	fint = clk->dpll_data->clk_ref->rate / n;

	pr_debug("clock: fint is %lu\n", fint);

	if (fint >= 750000 && fint <= 1000000)
		f = 0x3;
	else if (fint > 1000000 && fint <= 1250000)
		f = 0x4;
	else if (fint > 1250000 && fint <= 1500000)
		f = 0x5;
	else if (fint > 1500000 && fint <= 1750000)
		f = 0x6;
	else if (fint > 1750000 && fint <= 2100000)
		f = 0x7;
	else if (fint > 7500000 && fint <= 10000000)
		f = 0xB;
	else if (fint > 10000000 && fint <= 12500000)
		f = 0xC;
	else if (fint > 12500000 && fint <= 15000000)
		f = 0xD;
	else if (fint > 15000000 && fint <= 17500000)
		f = 0xE;
	else if (fint > 17500000 && fint <= 21000000)
		f = 0xF;
	else
		pr_debug("clock: unknown freqsel setting for %d\n", n);

	return f;
}

/* Non-CORE DPLL (e.g., DPLLs that do not control SDRC) clock functions */

/*
 * _omap3_noncore_dpll_lock - instruct a DPLL to lock and wait for readiness
 * @clk: pointer to a DPLL struct clk
 *
 * Instructs a non-CORE DPLL to lock.  Waits for the DPLL to report
 * readiness before returning.  Will save and restore the DPLL's
 * autoidle state across the enable, per the CDP code.  If the DPLL
 * locked successfully, return 0; if the DPLL did not lock in the time
 * allotted, or DPLL3 was passed in, return -EINVAL.
 */
static int _omap3_noncore_dpll_lock(struct clk *clk)
{
	u8 ai;
	int r;

	pr_debug("clock: locking DPLL %s\n", clk->name);

	ai = omap3_dpll_autoidle_read(clk);

	omap3_dpll_deny_idle(clk);

	_omap3_dpll_write_clken(clk, DPLL_LOCKED);

	r = _omap3_wait_dpll_status(clk, 1);

	if (ai)
		omap3_dpll_allow_idle(clk);

	return r;
}

/*
 * _omap3_noncore_dpll_bypass - instruct a DPLL to bypass and wait for readiness
 * @clk: pointer to a DPLL struct clk
 *
 * Instructs a non-CORE DPLL to enter low-power bypass mode.  In
 * bypass mode, the DPLL's rate is set equal to its parent clock's
 * rate.  Waits for the DPLL to report readiness before returning.
 * Will save and restore the DPLL's autoidle state across the enable,
 * per the CDP code.  If the DPLL entered bypass mode successfully,
 * return 0; if the DPLL did not enter bypass in the time allotted, or
 * DPLL3 was passed in, or the DPLL does not support low-power bypass,
 * return -EINVAL.
 */
static int _omap3_noncore_dpll_bypass(struct clk *clk)
{
	int r;
	u8 ai;

	if (!(clk->dpll_data->modes & (1 << DPLL_LOW_POWER_BYPASS)))
		return -EINVAL;

	pr_debug("clock: configuring DPLL %s for low-power bypass\n",
		 clk->name);

	ai = omap3_dpll_autoidle_read(clk);

	_omap3_dpll_write_clken(clk, DPLL_LOW_POWER_BYPASS);

	r = _omap3_wait_dpll_status(clk, 0);

	if (ai)
		omap3_dpll_allow_idle(clk);
	else
		omap3_dpll_deny_idle(clk);

	return r;
}

/*
 * _omap3_noncore_dpll_stop - instruct a DPLL to stop
 * @clk: pointer to a DPLL struct clk
 *
 * Instructs a non-CORE DPLL to enter low-power stop. Will save and
 * restore the DPLL's autoidle state across the stop, per the CDP
 * code.  If DPLL3 was passed in, or the DPLL does not support
 * low-power stop, return -EINVAL; otherwise, return 0.
 */
static int _omap3_noncore_dpll_stop(struct clk *clk)
{
	u8 ai;

	if (!(clk->dpll_data->modes & (1 << DPLL_LOW_POWER_STOP)))
		return -EINVAL;

	pr_debug("clock: stopping DPLL %s\n", clk->name);

	ai = omap3_dpll_autoidle_read(clk);

	_omap3_dpll_write_clken(clk, DPLL_LOW_POWER_STOP);

	if (ai)
		omap3_dpll_allow_idle(clk);
	else
		omap3_dpll_deny_idle(clk);

	return 0;
}

/**
 * omap3_noncore_dpll_enable - instruct a DPLL to enter bypass or lock mode
 * @clk: pointer to a DPLL struct clk
 *
 * Instructs a non-CORE DPLL to enable, e.g., to enter bypass or lock.
 * The choice of modes depends on the DPLL's programmed rate: if it is
 * the same as the DPLL's parent clock, it will enter bypass;
 * otherwise, it will enter lock.  This code will wait for the DPLL to
 * indicate readiness before returning, unless the DPLL takes too long
 * to enter the target state.  Intended to be used as the struct clk's
 * enable function.  If DPLL3 was passed in, or the DPLL does not
 * support low-power stop, or if the DPLL took too long to enter
 * bypass or lock, return -EINVAL; otherwise, return 0.
 */
static int omap3_noncore_dpll_enable(struct clk *clk)
{
	int r;
	struct dpll_data *dd;

	dd = clk->dpll_data;
	if (!dd)
		return -EINVAL;

	if (clk->rate == dd->clk_bypass->rate) {
		WARN_ON(clk->parent != dd->clk_bypass);
		r = _omap3_noncore_dpll_bypass(clk);
	} else {
		WARN_ON(clk->parent != dd->clk_ref);
		r = _omap3_noncore_dpll_lock(clk);
	}
	/* FIXME: this is dubious - if clk->rate has changed, what about propagating? */
	if (!r)
		clk->rate = omap2_get_dpll_rate(clk);

	return r;
}

/**
 * omap3_noncore_dpll_disable - instruct a DPLL to enter low-power stop
 * @clk: pointer to a DPLL struct clk
 *
 * Instructs a non-CORE DPLL to enter low-power stop.  This function is
 * intended for use in struct clkops.  No return value.
 */
static void omap3_noncore_dpll_disable(struct clk *clk)
{
	_omap3_noncore_dpll_stop(clk);
}

const struct clkops clkops_noncore_dpll_ops = {
	.enable		= omap3_noncore_dpll_enable,
	.disable	= omap3_noncore_dpll_disable,
};

/* Non-CORE DPLL rate set code */

/*
 * omap3_noncore_dpll_program - set non-core DPLL M,N values directly
 * @clk: struct clk * of DPLL to set
 * @m: DPLL multiplier to set
 * @n: DPLL divider to set
 * @freqsel: FREQSEL value to set
 *
 * Program the DPLL with the supplied M, N values, and wait for the DPLL to
 * lock..  Returns -EINVAL upon error, or 0 upon success.
 */
static int omap3_noncore_dpll_program(struct clk *clk, u16 m, u8 n, u16 freqsel)
{
	struct dpll_data *dd = clk->dpll_data;
	u32 v;

	/* 3430 ES2 TRM: 4.7.6.9 DPLL Programming Sequence */
	_omap3_noncore_dpll_bypass(clk);

	/* Set jitter correction */
	v = __raw_readl(dd->control_reg);
	v &= ~dd->freqsel_mask;
	v |= freqsel << __ffs(dd->freqsel_mask);
	__raw_writel(v, dd->control_reg);

	/* Set DPLL multiplier, divider */
	v = __raw_readl(dd->mult_div1_reg);
	v &= ~(dd->mult_mask | dd->div1_mask);
	v |= m << __ffs(dd->mult_mask);
	v |= (n - 1) << __ffs(dd->div1_mask);
	__raw_writel(v, dd->mult_div1_reg);

	/* We let the clock framework set the other output dividers later */

	/* REVISIT: Set ramp-up delay? */

	_omap3_noncore_dpll_lock(clk);

	return 0;
}

/**
 * omap3_noncore_dpll_set_rate - set non-core DPLL rate
 * @clk: struct clk * of DPLL to set
 * @rate: rounded target rate
 *
 * Set the DPLL CLKOUT to the target rate.  If the DPLL can enter
 * low-power bypass, and the target rate is the bypass source clock
 * rate, then configure the DPLL for bypass.  Otherwise, round the
 * target rate if it hasn't been done already, then program and lock
 * the DPLL.  Returns -EINVAL upon error, or 0 upon success.
 */
int omap3_noncore_dpll_set_rate(struct clk *clk, unsigned long rate)
{
	struct clk *new_parent = NULL;
	u16 freqsel;
	struct dpll_data *dd;
	int ret;

	if (!clk || !rate)
		return -EINVAL;

	dd = clk->dpll_data;
	if (!dd)
		return -EINVAL;

	if (rate == omap2_get_dpll_rate(clk))
		return 0;

	/*
	 * Ensure both the bypass and ref clocks are enabled prior to
	 * doing anything; we need the bypass clock running to reprogram
	 * the DPLL.
	 */
	omap2_clk_enable(dd->clk_bypass);
	omap2_clk_enable(dd->clk_ref);

	if (dd->clk_bypass->rate == rate &&
	    (clk->dpll_data->modes & (1 << DPLL_LOW_POWER_BYPASS))) {
		pr_debug("clock: %s: set rate: entering bypass.\n", clk->name);

		ret = _omap3_noncore_dpll_bypass(clk);
		if (!ret)
			new_parent = dd->clk_bypass;
	} else {
		if (dd->last_rounded_rate != rate)
			omap2_dpll_round_rate(clk, rate);

		if (dd->last_rounded_rate == 0)
			return -EINVAL;

		freqsel = _omap3_dpll_compute_freqsel(clk, dd->last_rounded_n);
		if (!freqsel)
			WARN_ON(1);

		pr_debug("clock: %s: set rate: locking rate to %lu.\n",
			 clk->name, rate);

		ret = omap3_noncore_dpll_program(clk, dd->last_rounded_m,
						 dd->last_rounded_n, freqsel);
		if (!ret)
			new_parent = dd->clk_ref;
	}
	if (!ret) {
		/*
		 * Switch the parent clock in the heirarchy, and make sure
		 * that the new parent's usecount is correct.  Note: we
		 * enable the new parent before disabling the old to avoid
		 * any unnecessary hardware disable->enable transitions.
		 */
		if (clk->usecount) {
			omap2_clk_enable(new_parent);
			omap2_clk_disable(clk->parent);
		}
		clk_reparent(clk, new_parent);
		clk->rate = rate;
	}
	omap2_clk_disable(dd->clk_ref);
	omap2_clk_disable(dd->clk_bypass);

	return 0;
}

int omap3_dpll4_set_rate(struct clk *clk, unsigned long rate)
{
	/*
	 * According to the 12-5 CDP code from TI, "Limitation 2.5"
	 * on 3430ES1 prevents us from changing DPLL multipliers or dividers
	 * on DPLL4.
	 */
	if (omap_rev() == OMAP3430_REV_ES1_0) {
		printk(KERN_ERR "clock: DPLL4 cannot change rate due to "
		       "silicon 'Limitation 2.5' on 3430ES1.\n");
		return -EINVAL;
	}
	return omap3_noncore_dpll_set_rate(clk, rate);
}


/*
 * CORE DPLL (DPLL3) rate programming functions
 *
 * These call into SRAM code to do the actual CM writes, since the SDRAM
 * is clocked from DPLL3.
 */

/**
 * omap3_core_dpll_m2_set_rate - set CORE DPLL M2 divider
 * @clk: struct clk * of DPLL to set
 * @rate: rounded target rate
 *
 * Program the DPLL M2 divider with the rounded target rate.  Returns
 * -EINVAL upon error, or 0 upon success.
 */
int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate)
{
	u32 new_div = 0;
	u32 unlock_dll = 0;
	u32 c;
	unsigned long validrate, sdrcrate, _mpurate;
	struct omap_sdrc_params *sdrc_cs0;
	struct omap_sdrc_params *sdrc_cs1;
	int ret;

	if (!clk || !rate)
		return -EINVAL;

	validrate = omap2_clksel_round_rate_div(clk, rate, &new_div);
	if (validrate != rate)
		return -EINVAL;

	sdrcrate = sdrc_ick_p->rate;
	if (rate > clk->rate)
		sdrcrate <<= ((rate / clk->rate) >> 1);
	else
		sdrcrate >>= ((clk->rate / rate) >> 1);

	ret = omap2_sdrc_get_params(sdrcrate, &sdrc_cs0, &sdrc_cs1);
	if (ret)
		return -EINVAL;

	if (sdrcrate < MIN_SDRC_DLL_LOCK_FREQ) {
		pr_debug("clock: will unlock SDRC DLL\n");
		unlock_dll = 1;
	}

	/*
	 * XXX This only needs to be done when the CPU frequency changes
	 */
	_mpurate = arm_fck_p->rate / CYCLES_PER_MHZ;
	c = (_mpurate << SDRC_MPURATE_SCALE) >> SDRC_MPURATE_BASE_SHIFT;
	c += 1;  /* for safety */
	c *= SDRC_MPURATE_LOOPS;
	c >>= SDRC_MPURATE_SCALE;
	if (c == 0)
		c = 1;

	pr_debug("clock: changing CORE DPLL rate from %lu to %lu\n", clk->rate,
		 validrate);
	pr_debug("clock: SDRC CS0 timing params used:"
		 " RFR %08x CTRLA %08x CTRLB %08x MR %08x\n",
		 sdrc_cs0->rfr_ctrl, sdrc_cs0->actim_ctrla,
		 sdrc_cs0->actim_ctrlb, sdrc_cs0->mr);
	if (sdrc_cs1)
		pr_debug("clock: SDRC CS1 timing params used: "
		 " RFR %08x CTRLA %08x CTRLB %08x MR %08x\n",
		 sdrc_cs1->rfr_ctrl, sdrc_cs1->actim_ctrla,
		 sdrc_cs1->actim_ctrlb, sdrc_cs1->mr);

	if (sdrc_cs1)
		omap3_configure_core_dpll(
				  new_div, unlock_dll, c, rate > clk->rate,
				  sdrc_cs0->rfr_ctrl, sdrc_cs0->actim_ctrla,
				  sdrc_cs0->actim_ctrlb, sdrc_cs0->mr,
				  sdrc_cs1->rfr_ctrl, sdrc_cs1->actim_ctrla,
				  sdrc_cs1->actim_ctrlb, sdrc_cs1->mr);
	else
		omap3_configure_core_dpll(
				  new_div, unlock_dll, c, rate > clk->rate,
				  sdrc_cs0->rfr_ctrl, sdrc_cs0->actim_ctrla,
				  sdrc_cs0->actim_ctrlb, sdrc_cs0->mr,
				  0, 0, 0, 0);

	return 0;
}


/* DPLL autoidle read/set code */


/**
 * omap3_dpll_autoidle_read - read a DPLL's autoidle bits
 * @clk: struct clk * of the DPLL to read
 *
 * Return the DPLL's autoidle bits, shifted down to bit 0.  Returns
 * -EINVAL if passed a null pointer or if the struct clk does not
 * appear to refer to a DPLL.
 */
u32 omap3_dpll_autoidle_read(struct clk *clk)
{
	const struct dpll_data *dd;
	u32 v;

	if (!clk || !clk->dpll_data)
		return -EINVAL;

	dd = clk->dpll_data;

	v = __raw_readl(dd->autoidle_reg);
	v &= dd->autoidle_mask;
	v >>= __ffs(dd->autoidle_mask);

	return v;
}

/**
 * omap3_dpll_allow_idle - enable DPLL autoidle bits
 * @clk: struct clk * of the DPLL to operate on
 *
 * Enable DPLL automatic idle control.  This automatic idle mode
 * switching takes effect only when the DPLL is locked, at least on
 * OMAP3430.  The DPLL will enter low-power stop when its downstream
 * clocks are gated.  No return value.
 */
void omap3_dpll_allow_idle(struct clk *clk)
{
	const struct dpll_data *dd;
	u32 v;

	if (!clk || !clk->dpll_data)
		return;

	dd = clk->dpll_data;

	/*
	 * REVISIT: CORE DPLL can optionally enter low-power bypass
	 * by writing 0x5 instead of 0x1.  Add some mechanism to
	 * optionally enter this mode.
	 */
	v = __raw_readl(dd->autoidle_reg);
	v &= ~dd->autoidle_mask;
	v |= DPLL_AUTOIDLE_LOW_POWER_STOP << __ffs(dd->autoidle_mask);
	__raw_writel(v, dd->autoidle_reg);
}

/**
 * omap3_dpll_deny_idle - prevent DPLL from automatically idling
 * @clk: struct clk * of the DPLL to operate on
 *
 * Disable DPLL automatic idle control.  No return value.
 */
void omap3_dpll_deny_idle(struct clk *clk)
{
	const struct dpll_data *dd;
	u32 v;

	if (!clk || !clk->dpll_data)
		return;

	dd = clk->dpll_data;

	v = __raw_readl(dd->autoidle_reg);
	v &= ~dd->autoidle_mask;
	v |= DPLL_AUTOIDLE_DISABLE << __ffs(dd->autoidle_mask);
	__raw_writel(v, dd->autoidle_reg);
}

/* Clock control for DPLL outputs */

/**
 * omap3_clkoutx2_recalc - recalculate DPLL X2 output virtual clock rate
 * @clk: DPLL output struct clk
 *
 * Using parent clock DPLL data, look up DPLL state.  If locked, set our
 * rate to the dpll_clk * 2; otherwise, just use dpll_clk.
 */
unsigned long omap3_clkoutx2_recalc(struct clk *clk)
{
	const struct dpll_data *dd;
	unsigned long rate;
	u32 v;
	struct clk *pclk;

	/* Walk up the parents of clk, looking for a DPLL */
	pclk = clk->parent;
	while (pclk && !pclk->dpll_data)
		pclk = pclk->parent;

	/* clk does not have a DPLL as a parent? */
	WARN_ON(!pclk);

	dd = pclk->dpll_data;

	WARN_ON(!dd->enable_mask);

	v = __raw_readl(dd->control_reg) & dd->enable_mask;
	v >>= __ffs(dd->enable_mask);
	if (v != OMAP3XXX_EN_DPLL_LOCKED)
		rate = clk->parent->rate;
	else
		rate = clk->parent->rate * 2;
	return rate;
}

/* Common clock code */

/*
 * As it is structured now, this will prevent an OMAP2/3 multiboot
 * kernel from compiling.  This will need further attention.
 */
#if defined(CONFIG_ARCH_OMAP3)

struct clk_functions omap2_clk_functions = {
	.clk_enable		= omap2_clk_enable,
	.clk_disable		= omap2_clk_disable,
	.clk_round_rate		= omap2_clk_round_rate,
	.clk_set_rate		= omap2_clk_set_rate,
	.clk_set_parent		= omap2_clk_set_parent,
	.clk_disable_unused	= omap2_clk_disable_unused,
};

/*
 * Set clocks for bypass mode for reboot to work.
 */
void omap2_clk_prepare_for_reboot(void)
{
	/* REVISIT: Not ready for 343x */
#if 0
	u32 rate;

	if (vclk == NULL || sclk == NULL)
		return;

	rate = clk_get_rate(sclk);
	clk_set_rate(vclk, rate);
#endif
}

void omap3_clk_lock_dpll5(void)
{
	struct clk *dpll5_clk;
	struct clk *dpll5_m2_clk;

	dpll5_clk = clk_get(NULL, "dpll5_ck");
	clk_set_rate(dpll5_clk, DPLL5_FREQ_FOR_USBHOST);
	clk_enable(dpll5_clk);

	/* Enable autoidle to allow it to enter low power bypass */
	omap3_dpll_allow_idle(dpll5_clk);

	/* Program dpll5_m2_clk divider for no division */
	dpll5_m2_clk = clk_get(NULL, "dpll5_m2_ck");
	clk_enable(dpll5_m2_clk);
	clk_set_rate(dpll5_m2_clk, DPLL5_FREQ_FOR_USBHOST);

	clk_disable(dpll5_m2_clk);
	clk_disable(dpll5_clk);
	return;
}

/* REVISIT: Move this init stuff out into clock.c */

/*
 * Switch the MPU rate if specified on cmdline.
 * We cannot do this early until cmdline is parsed.
 */
static int __init omap2_clk_arch_init(void)
{
	struct clk *osc_sys_ck, *dpll1_ck, *arm_fck, *core_ck;
	unsigned long osc_sys_rate;

	if (!mpurate)
		return -EINVAL;

	/* XXX test these for success */
	dpll1_ck = clk_get(NULL, "dpll1_ck");
	arm_fck = clk_get(NULL, "arm_fck");
	core_ck = clk_get(NULL, "core_ck");
	osc_sys_ck = clk_get(NULL, "osc_sys_ck");

	/* REVISIT: not yet ready for 343x */
	if (clk_set_rate(dpll1_ck, mpurate))
		printk(KERN_ERR "*** Unable to set MPU rate\n");

	recalculate_root_clocks();

	osc_sys_rate = clk_get_rate(osc_sys_ck);

	pr_info("Switched to new clocking rate (Crystal/Core/MPU): "
		"%ld.%01ld/%ld/%ld MHz\n",
		(osc_sys_rate / 1000000),
		((osc_sys_rate / 100000) % 10),
		(clk_get_rate(core_ck) / 1000000),
		(clk_get_rate(arm_fck) / 1000000));

	calibrate_delay();

	return 0;
}
arch_initcall(omap2_clk_arch_init);


#endif