[linux-2.6-block.git] / arch / arm / mach-omap2 / clockdomain.c

/*
 * OMAP2/3 clockdomain framework functions
 *
 * Copyright (C) 2008 Texas Instruments, Inc.
 * Copyright (C) 2008-2009 Nokia Corporation
 *
 * Written by Paul Walmsley and Jouni Högander
 *
 * 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/limits.h>
#include <linux/err.h>

#include <linux/io.h>

#include <linux/bitops.h>

#include <plat/clock.h>

#include "prm.h"
#include "prm-regbits-24xx.h"
#include "cm.h"

#include <plat/powerdomain.h>
#include <plat/clockdomain.h>

/* clkdm_list contains all registered struct clockdomains */
static LIST_HEAD(clkdm_list);

/* clkdm_mutex protects clkdm_list add and del ops */
static DEFINE_MUTEX(clkdm_mutex);

/* array of powerdomain deps to be added/removed when clkdm in hwsup mode */
static struct clkdm_pwrdm_autodep *autodeps;


/* Private functions */

/*
 * _autodep_lookup - resolve autodep pwrdm names to pwrdm pointers; store
 * @autodep: struct clkdm_pwrdm_autodep * to resolve
 *
 * Resolve autodep powerdomain names to powerdomain pointers via
 * pwrdm_lookup() and store the pointers in the autodep structure.  An
 * "autodep" is a powerdomain sleep/wakeup dependency that is
 * automatically added and removed whenever clocks in the associated
 * clockdomain are enabled or disabled (respectively) when the
 * clockdomain is in hardware-supervised mode.	Meant to be called
 * once at clockdomain layer initialization, since these should remain
 * fixed for a particular architecture.  No return value.
 */
static void _autodep_lookup(struct clkdm_pwrdm_autodep *autodep)
{
	struct powerdomain *pwrdm;

	if (!autodep)
		return;

	if (!omap_chip_is(autodep->omap_chip))
		return;

	pwrdm = pwrdm_lookup(autodep->pwrdm.name);
	if (!pwrdm) {
		pr_err("clockdomain: autodeps: powerdomain %s does not exist\n",
			 autodep->pwrdm.name);
		pwrdm = ERR_PTR(-ENOENT);
	}
	autodep->pwrdm.ptr = pwrdm;
}

/*
 * _clkdm_add_autodeps - add auto sleepdeps/wkdeps to clkdm upon clock enable
 * @clkdm: struct clockdomain *
 *
 * Add the "autodep" sleep & wakeup dependencies to clockdomain 'clkdm'
 * in hardware-supervised mode.  Meant to be called from clock framework
 * when a clock inside clockdomain 'clkdm' is enabled.	No return value.
 */
static void _clkdm_add_autodeps(struct clockdomain *clkdm)
{
	struct clkdm_pwrdm_autodep *autodep;

	for (autodep = autodeps; autodep->pwrdm.ptr; autodep++) {
		if (IS_ERR(autodep->pwrdm.ptr))
			continue;

		if (!omap_chip_is(autodep->omap_chip))
			continue;

		pr_debug("clockdomain: adding %s sleepdep/wkdep for "
			 "pwrdm %s\n", autodep->pwrdm.ptr->name,
			 clkdm->pwrdm.ptr->name);

		pwrdm_add_sleepdep(clkdm->pwrdm.ptr, autodep->pwrdm.ptr);
		pwrdm_add_wkdep(clkdm->pwrdm.ptr, autodep->pwrdm.ptr);
	}
}

/*
 * _clkdm_add_autodeps - remove auto sleepdeps/wkdeps from clkdm
 * @clkdm: struct clockdomain *
 *
 * Remove the "autodep" sleep & wakeup dependencies from clockdomain 'clkdm'
 * in hardware-supervised mode.  Meant to be called from clock framework
 * when a clock inside clockdomain 'clkdm' is disabled.  No return value.
 */
static void _clkdm_del_autodeps(struct clockdomain *clkdm)
{
	struct clkdm_pwrdm_autodep *autodep;

	for (autodep = autodeps; autodep->pwrdm.ptr; autodep++) {
		if (IS_ERR(autodep->pwrdm.ptr))
			continue;

		if (!omap_chip_is(autodep->omap_chip))
			continue;

		pr_debug("clockdomain: removing %s sleepdep/wkdep for "
			 "pwrdm %s\n", autodep->pwrdm.ptr->name,
			 clkdm->pwrdm.ptr->name);

		pwrdm_del_sleepdep(clkdm->pwrdm.ptr, autodep->pwrdm.ptr);
		pwrdm_del_wkdep(clkdm->pwrdm.ptr, autodep->pwrdm.ptr);
	}
}

/*
 * _omap2_clkdm_set_hwsup - set the hwsup idle transition bit
 * @clkdm: struct clockdomain *
 * @enable: int 0 to disable, 1 to enable
 *
 * Internal helper for actually switching the bit that controls hwsup
 * idle transitions for clkdm.
 */
static void _omap2_clkdm_set_hwsup(struct clockdomain *clkdm, int enable)
{
	u32 v;

	if (cpu_is_omap24xx()) {
		if (enable)
			v = OMAP24XX_CLKSTCTRL_ENABLE_AUTO;
		else
			v = OMAP24XX_CLKSTCTRL_DISABLE_AUTO;
	} else if (cpu_is_omap34xx()) {
		if (enable)
			v = OMAP34XX_CLKSTCTRL_ENABLE_AUTO;
		else
			v = OMAP34XX_CLKSTCTRL_DISABLE_AUTO;
	} else {
		BUG();
	}

	cm_rmw_mod_reg_bits(clkdm->clktrctrl_mask,
			    v << __ffs(clkdm->clktrctrl_mask),
			    clkdm->pwrdm.ptr->prcm_offs, CM_CLKSTCTRL);
}

static struct clockdomain *_clkdm_lookup(const char *name)
{
	struct clockdomain *clkdm, *temp_clkdm;

	if (!name)
		return NULL;

	clkdm = NULL;

	list_for_each_entry(temp_clkdm, &clkdm_list, node) {
		if (!strcmp(name, temp_clkdm->name)) {
			clkdm = temp_clkdm;
			break;
		}
	}

	return clkdm;
}


/* Public functions */

/**
 * clkdm_init - set up the clockdomain layer
 * @clkdms: optional pointer to an array of clockdomains to register
 * @init_autodeps: optional pointer to an array of autodeps to register
 *
 * Set up internal state.  If a pointer to an array of clockdomains
 * was supplied, loop through the list of clockdomains, register all
 * that are available on the current platform.	Similarly, if a
 * pointer to an array of clockdomain-powerdomain autodependencies was
 * provided, register those.  No return value.
 */
void clkdm_init(struct clockdomain **clkdms,
		struct clkdm_pwrdm_autodep *init_autodeps)
{
	struct clockdomain **c = NULL;
	struct clkdm_pwrdm_autodep *autodep = NULL;

	if (clkdms)
		for (c = clkdms; *c; c++)
			clkdm_register(*c);

	autodeps = init_autodeps;
	if (autodeps)
		for (autodep = autodeps; autodep->pwrdm.ptr; autodep++)
			_autodep_lookup(autodep);
}

/**
 * clkdm_register - register a clockdomain
 * @clkdm: struct clockdomain * to register
 *
 * Adds a clockdomain to the internal clockdomain list.
 * Returns -EINVAL if given a null pointer, -EEXIST if a clockdomain is
 * already registered by the provided name, or 0 upon success.
 */
int clkdm_register(struct clockdomain *clkdm)
{
	int ret = -EINVAL;
	struct powerdomain *pwrdm;

	if (!clkdm || !clkdm->name)
		return -EINVAL;

	if (!omap_chip_is(clkdm->omap_chip))
		return -EINVAL;

	pwrdm = pwrdm_lookup(clkdm->pwrdm.name);
	if (!pwrdm) {
		pr_err("clockdomain: %s: powerdomain %s does not exist\n",
			clkdm->name, clkdm->pwrdm.name);
		return -EINVAL;
	}
	clkdm->pwrdm.ptr = pwrdm;

	mutex_lock(&clkdm_mutex);
	/* Verify that the clockdomain is not already registered */
	if (_clkdm_lookup(clkdm->name)) {
		ret = -EEXIST;
		goto cr_unlock;
	}

	list_add(&clkdm->node, &clkdm_list);

	pwrdm_add_clkdm(pwrdm, clkdm);

	pr_debug("clockdomain: registered %s\n", clkdm->name);
	ret = 0;

cr_unlock:
	mutex_unlock(&clkdm_mutex);

	return ret;
}

/**
 * clkdm_unregister - unregister a clockdomain
 * @clkdm: struct clockdomain * to unregister
 *
 * Removes a clockdomain from the internal clockdomain list.  Returns
 * -EINVAL if clkdm argument is NULL.
 */
int clkdm_unregister(struct clockdomain *clkdm)
{
	if (!clkdm)
		return -EINVAL;

	pwrdm_del_clkdm(clkdm->pwrdm.ptr, clkdm);

	mutex_lock(&clkdm_mutex);
	list_del(&clkdm->node);
	mutex_unlock(&clkdm_mutex);

	pr_debug("clockdomain: unregistered %s\n", clkdm->name);

	return 0;
}

/**
 * clkdm_lookup - look up a clockdomain by name, return a pointer
 * @name: name of clockdomain
 *
 * Find a registered clockdomain by its name.  Returns a pointer to the
 * struct clockdomain if found, or NULL otherwise.
 */
struct clockdomain *clkdm_lookup(const char *name)
{
	struct clockdomain *clkdm, *temp_clkdm;

	if (!name)
		return NULL;

	clkdm = NULL;

	mutex_lock(&clkdm_mutex);
	list_for_each_entry(temp_clkdm, &clkdm_list, node) {
		if (!strcmp(name, temp_clkdm->name)) {
			clkdm = temp_clkdm;
			break;
		}
	}
	mutex_unlock(&clkdm_mutex);

	return clkdm;
}

/**
 * clkdm_for_each - call function on each registered clockdomain
 * @fn: callback function *
 *
 * Call the supplied function for each registered clockdomain.
 * The callback function can return anything but 0 to bail
 * out early from the iterator.  The callback function is called with
 * the clkdm_mutex held, so no clockdomain structure manipulation
 * functions should be called from the callback, although hardware
 * clockdomain control functions are fine.  Returns the last return
 * value of the callback function, which should be 0 for success or
 * anything else to indicate failure; or -EINVAL if the function pointer
 * is null.
 */
int clkdm_for_each(int (*fn)(struct clockdomain *clkdm, void *user),
			void *user)
{
	struct clockdomain *clkdm;
	int ret = 0;

	if (!fn)
		return -EINVAL;

	mutex_lock(&clkdm_mutex);
	list_for_each_entry(clkdm, &clkdm_list, node) {
		ret = (*fn)(clkdm, user);
		if (ret)
			break;
	}
	mutex_unlock(&clkdm_mutex);

	return ret;
}


/**
 * clkdm_get_pwrdm - return a ptr to the pwrdm that this clkdm resides in
 * @clkdm: struct clockdomain *
 *
 * Return a pointer to the struct powerdomain that the specified clockdomain
 * 'clkdm' exists in, or returns NULL if clkdm argument is NULL.
 */
struct powerdomain *clkdm_get_pwrdm(struct clockdomain *clkdm)
{
	if (!clkdm)
		return NULL;

	return clkdm->pwrdm.ptr;
}


/* Hardware clockdomain control */

/**
 * omap2_clkdm_clktrctrl_read - read the clkdm's current state transition mode
 * @clk: struct clk * of a clockdomain
 *
 * Return the clockdomain's current state transition mode from the
 * corresponding domain CM_CLKSTCTRL register.	Returns -EINVAL if clk
 * is NULL or the current mode upon success.
 */
static int omap2_clkdm_clktrctrl_read(struct clockdomain *clkdm)
{
	u32 v;

	if (!clkdm)
		return -EINVAL;

	v = cm_read_mod_reg(clkdm->pwrdm.ptr->prcm_offs, CM_CLKSTCTRL);
	v &= clkdm->clktrctrl_mask;
	v >>= __ffs(clkdm->clktrctrl_mask);

	return v;
}

/**
 * omap2_clkdm_sleep - force clockdomain sleep transition
 * @clkdm: struct clockdomain *
 *
 * Instruct the CM to force a sleep transition on the specified
 * clockdomain 'clkdm'.  Returns -EINVAL if clk is NULL or if
 * clockdomain does not support software-initiated sleep; 0 upon
 * success.
 */
int omap2_clkdm_sleep(struct clockdomain *clkdm)
{
	if (!clkdm)
		return -EINVAL;

	if (!(clkdm->flags & CLKDM_CAN_FORCE_SLEEP)) {
		pr_debug("clockdomain: %s does not support forcing "
			 "sleep via software\n", clkdm->name);
		return -EINVAL;
	}

	pr_debug("clockdomain: forcing sleep on %s\n", clkdm->name);

	if (cpu_is_omap24xx()) {

		cm_set_mod_reg_bits(OMAP24XX_FORCESTATE,
				    clkdm->pwrdm.ptr->prcm_offs, PM_PWSTCTRL);

	} else if (cpu_is_omap34xx()) {

		u32 v = (OMAP34XX_CLKSTCTRL_FORCE_SLEEP <<
			 __ffs(clkdm->clktrctrl_mask));

		cm_rmw_mod_reg_bits(clkdm->clktrctrl_mask, v,
				    clkdm->pwrdm.ptr->prcm_offs, CM_CLKSTCTRL);

	} else {
		BUG();
	};

	return 0;
}

/**
 * omap2_clkdm_wakeup - force clockdomain wakeup transition
 * @clkdm: struct clockdomain *
 *
 * Instruct the CM to force a wakeup transition on the specified
 * clockdomain 'clkdm'.  Returns -EINVAL if clkdm is NULL or if the
 * clockdomain does not support software-controlled wakeup; 0 upon
 * success.
 */
int omap2_clkdm_wakeup(struct clockdomain *clkdm)
{
	if (!clkdm)
		return -EINVAL;

	if (!(clkdm->flags & CLKDM_CAN_FORCE_WAKEUP)) {
		pr_debug("clockdomain: %s does not support forcing "
			 "wakeup via software\n", clkdm->name);
		return -EINVAL;
	}

	pr_debug("clockdomain: forcing wakeup on %s\n", clkdm->name);

	if (cpu_is_omap24xx()) {

		cm_clear_mod_reg_bits(OMAP24XX_FORCESTATE,
				      clkdm->pwrdm.ptr->prcm_offs, PM_PWSTCTRL);

	} else if (cpu_is_omap34xx()) {

		u32 v = (OMAP34XX_CLKSTCTRL_FORCE_WAKEUP <<
			 __ffs(clkdm->clktrctrl_mask));

		cm_rmw_mod_reg_bits(clkdm->clktrctrl_mask, v,
				    clkdm->pwrdm.ptr->prcm_offs, CM_CLKSTCTRL);

	} else {
		BUG();
	};

	return 0;
}

/**
 * omap2_clkdm_allow_idle - enable hwsup idle transitions for clkdm
 * @clkdm: struct clockdomain *
 *
 * Allow the hardware to automatically switch the clockdomain into
 * active or idle states, as needed by downstream clocks.  If the
 * clockdomain has any downstream clocks enabled in the clock
 * framework, wkdep/sleepdep autodependencies are added; this is so
 * device drivers can read and write to the device.  No return value.
 */
void omap2_clkdm_allow_idle(struct clockdomain *clkdm)
{
	if (!clkdm)
		return;

	if (!(clkdm->flags & CLKDM_CAN_ENABLE_AUTO)) {
		pr_debug("clock: automatic idle transitions cannot be enabled "
			 "on clockdomain %s\n", clkdm->name);
		return;
	}

	pr_debug("clockdomain: enabling automatic idle transitions for %s\n",
		 clkdm->name);

	if (atomic_read(&clkdm->usecount) > 0)
		_clkdm_add_autodeps(clkdm);

	_omap2_clkdm_set_hwsup(clkdm, 1);

	pwrdm_clkdm_state_switch(clkdm);
}

/**
 * omap2_clkdm_deny_idle - disable hwsup idle transitions for clkdm
 * @clkdm: struct clockdomain *
 *
 * Prevent the hardware from automatically switching the clockdomain
 * into inactive or idle states.  If the clockdomain has downstream
 * clocks enabled in the clock framework, wkdep/sleepdep
 * autodependencies are removed.  No return value.
 */
void omap2_clkdm_deny_idle(struct clockdomain *clkdm)
{
	if (!clkdm)
		return;

	if (!(clkdm->flags & CLKDM_CAN_DISABLE_AUTO)) {
		pr_debug("clockdomain: automatic idle transitions cannot be "
			 "disabled on %s\n", clkdm->name);
		return;
	}

	pr_debug("clockdomain: disabling automatic idle transitions for %s\n",
		 clkdm->name);

	_omap2_clkdm_set_hwsup(clkdm, 0);

	if (atomic_read(&clkdm->usecount) > 0)
		_clkdm_del_autodeps(clkdm);
}


/* Clockdomain-to-clock framework interface code */

/**
 * omap2_clkdm_clk_enable - add an enabled downstream clock to this clkdm
 * @clkdm: struct clockdomain *
 * @clk: struct clk * of the enabled downstream clock
 *
 * Increment the usecount of this clockdomain 'clkdm' and ensure that
 * it is awake.  Intended to be called by clk_enable() code.  If the
 * clockdomain is in software-supervised idle mode, force the
 * clockdomain to wake.  If the clockdomain is in hardware-supervised
 * idle mode, add clkdm-pwrdm autodependencies, to ensure that devices
 * in the clockdomain can be read from/written to by on-chip processors.
 * Returns -EINVAL if passed null pointers; returns 0 upon success or
 * if the clockdomain is in hwsup idle mode.
 */
int omap2_clkdm_clk_enable(struct clockdomain *clkdm, struct clk *clk)
{
	int v;

	/*
	 * XXX Rewrite this code to maintain a list of enabled
	 * downstream clocks for debugging purposes?
	 */

	if (!clkdm || !clk || !clkdm->clktrctrl_mask)
		return -EINVAL;

	if (atomic_inc_return(&clkdm->usecount) > 1)
		return 0;

	/* Clockdomain now has one enabled downstream clock */

	pr_debug("clockdomain: clkdm %s: clk %s now enabled\n", clkdm->name,
		 clk->name);

	v = omap2_clkdm_clktrctrl_read(clkdm);

	if ((cpu_is_omap34xx() && v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) ||
	    (cpu_is_omap24xx() && v == OMAP24XX_CLKSTCTRL_ENABLE_AUTO)) {
		/* Disable HW transitions when we are changing deps */
		_omap2_clkdm_set_hwsup(clkdm, 0);
		_clkdm_add_autodeps(clkdm);
		_omap2_clkdm_set_hwsup(clkdm, 1);
	} else {
		omap2_clkdm_wakeup(clkdm);
	}

	pwrdm_wait_transition(clkdm->pwrdm.ptr);
	pwrdm_clkdm_state_switch(clkdm);

	return 0;
}

/**
 * omap2_clkdm_clk_disable - remove an enabled downstream clock from this clkdm
 * @clkdm: struct clockdomain *
 * @clk: struct clk * of the disabled downstream clock
 *
 * Decrement the usecount of this clockdomain 'clkdm'. Intended to be
 * called by clk_disable() code.  If the usecount goes to 0, put the
 * clockdomain to sleep (software-supervised mode) or remove the
 * clkdm-pwrdm autodependencies (hardware-supervised mode).  Returns
 * -EINVAL if passed null pointers; -ERANGE if the clkdm usecount
 * underflows and debugging is enabled; or returns 0 upon success or
 * if the clockdomain is in hwsup idle mode.
 */
int omap2_clkdm_clk_disable(struct clockdomain *clkdm, struct clk *clk)
{
	int v;

	/*
	 * XXX Rewrite this code to maintain a list of enabled
	 * downstream clocks for debugging purposes?
	 */

	if (!clkdm || !clk || !clkdm->clktrctrl_mask)
		return -EINVAL;

#ifdef DEBUG
	if (atomic_read(&clkdm->usecount) == 0) {
		WARN_ON(1); /* underflow */
		return -ERANGE;
	}
#endif

	if (atomic_dec_return(&clkdm->usecount) > 0)
		return 0;

	/* All downstream clocks of this clockdomain are now disabled */

	pr_debug("clockdomain: clkdm %s: clk %s now disabled\n", clkdm->name,
		 clk->name);

	v = omap2_clkdm_clktrctrl_read(clkdm);

	if ((cpu_is_omap34xx() && v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) ||
	    (cpu_is_omap24xx() && v == OMAP24XX_CLKSTCTRL_ENABLE_AUTO)) {
		/* Disable HW transitions when we are changing deps */
		_omap2_clkdm_set_hwsup(clkdm, 0);
		_clkdm_del_autodeps(clkdm);
		_omap2_clkdm_set_hwsup(clkdm, 1);
	} else {
		omap2_clkdm_sleep(clkdm);
	}

	pwrdm_clkdm_state_switch(clkdm);

	return 0;
}
Commit	Line	Data
d459bfe0 PW	1	/*
	2	* OMAP2/3 clockdomain framework functions
	3	*
	4	* Copyright (C) 2008 Texas Instruments, Inc.
33903eb5	5	* Copyright (C) 2008-2009 Nokia Corporation
d459bfe0 PW	6	*
	7	* Written by Paul Walmsley and Jouni Högander
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License version 2 as
	11	* published by the Free Software Foundation.
	12	*/
33903eb5	13	#undef DEBUG
d459bfe0 PW	14
	15	#include <linux/module.h>
	16	#include <linux/kernel.h>
	17	#include <linux/device.h>
	18	#include <linux/list.h>
	19	#include <linux/errno.h>
	20	#include <linux/delay.h>
	21	#include <linux/clk.h>
	22	#include <linux/limits.h>
5b74c676	23	#include <linux/err.h>
d459bfe0 PW	24
	25	#include <linux/io.h>
	26
	27	#include <linux/bitops.h>
	28
ce491cf8	29	#include <plat/clock.h>
d459bfe0 PW	30
	31	#include "prm.h"
	32	#include "prm-regbits-24xx.h"
	33	#include "cm.h"
	34
ce491cf8 TL	35	#include <plat/powerdomain.h>
ce491cf8 TL	36	#include <plat/clockdomain.h>
d459bfe0 PW	37
	38	/* clkdm_list contains all registered struct clockdomains */
	39	static LIST_HEAD(clkdm_list);
	40
	41	/* clkdm_mutex protects clkdm_list add and del ops */
	42	static DEFINE_MUTEX(clkdm_mutex);
	43
	44	/* array of powerdomain deps to be added/removed when clkdm in hwsup mode */
	45	static struct clkdm_pwrdm_autodep *autodeps;
	46
	47
	48	/* Private functions */
	49
	50	/*
	51	* _autodep_lookup - resolve autodep pwrdm names to pwrdm pointers; store
	52	* @autodep: struct clkdm_pwrdm_autodep * to resolve
	53	*
	54	* Resolve autodep powerdomain names to powerdomain pointers via
	55	* pwrdm_lookup() and store the pointers in the autodep structure. An
	56	* "autodep" is a powerdomain sleep/wakeup dependency that is
	57	* automatically added and removed whenever clocks in the associated
	58	* clockdomain are enabled or disabled (respectively) when the
	59	* clockdomain is in hardware-supervised mode. Meant to be called
	60	* once at clockdomain layer initialization, since these should remain
	61	* fixed for a particular architecture. No return value.
	62	*/
	63	static void _autodep_lookup(struct clkdm_pwrdm_autodep *autodep)
	64	{
	65	struct powerdomain *pwrdm;
	66
	67	if (!autodep)
	68	return;
	69
	70	if (!omap_chip_is(autodep->omap_chip))
	71	return;
	72
5b74c676	73	pwrdm = pwrdm_lookup(autodep->pwrdm.name);
d459bfe0	74	if (!pwrdm) {
7aec53ac RK	75	pr_err("clockdomain: autodeps: powerdomain %s does not exist\n",
7aec53ac RK	76	autodep->pwrdm.name);
5b74c676	77	pwrdm = ERR_PTR(-ENOENT);
d459bfe0	78	}
5b74c676	79	autodep->pwrdm.ptr = pwrdm;
d459bfe0 PW	80	}
	81
	82	/*
	83	* _clkdm_add_autodeps - add auto sleepdeps/wkdeps to clkdm upon clock enable
	84	* @clkdm: struct clockdomain *
	85	*
	86	* Add the "autodep" sleep & wakeup dependencies to clockdomain 'clkdm'
	87	* in hardware-supervised mode. Meant to be called from clock framework
	88	* when a clock inside clockdomain 'clkdm' is enabled. No return value.
	89	*/
	90	static void _clkdm_add_autodeps(struct clockdomain *clkdm)
	91	{
	92	struct clkdm_pwrdm_autodep *autodep;
	93
5b74c676 PW	94	for (autodep = autodeps; autodep->pwrdm.ptr; autodep++) {
5b74c676 PW	95	if (IS_ERR(autodep->pwrdm.ptr))
d459bfe0 PW	96	continue;
d459bfe0 PW	97
d96df00d PW	98	if (!omap_chip_is(autodep->omap_chip))
	99	continue;
	100
d459bfe0	101	pr_debug("clockdomain: adding %s sleepdep/wkdep for "
5b74c676 PW	102	"pwrdm %s\n", autodep->pwrdm.ptr->name,
5b74c676 PW	103	clkdm->pwrdm.ptr->name);
d459bfe0	104
5b74c676 PW	105	pwrdm_add_sleepdep(clkdm->pwrdm.ptr, autodep->pwrdm.ptr);
5b74c676 PW	106	pwrdm_add_wkdep(clkdm->pwrdm.ptr, autodep->pwrdm.ptr);
d459bfe0 PW	107	}
	108	}
	109
	110	/*
	111	* _clkdm_add_autodeps - remove auto sleepdeps/wkdeps from clkdm
	112	* @clkdm: struct clockdomain *
	113	*
	114	* Remove the "autodep" sleep & wakeup dependencies from clockdomain 'clkdm'
	115	* in hardware-supervised mode. Meant to be called from clock framework
	116	* when a clock inside clockdomain 'clkdm' is disabled. No return value.
	117	*/
	118	static void _clkdm_del_autodeps(struct clockdomain *clkdm)
	119	{
	120	struct clkdm_pwrdm_autodep *autodep;
	121
5b74c676 PW	122	for (autodep = autodeps; autodep->pwrdm.ptr; autodep++) {
5b74c676 PW	123	if (IS_ERR(autodep->pwrdm.ptr))
d459bfe0 PW	124	continue;
d459bfe0 PW	125
d96df00d PW	126	if (!omap_chip_is(autodep->omap_chip))
	127	continue;
	128
d459bfe0	129	pr_debug("clockdomain: removing %s sleepdep/wkdep for "
5b74c676 PW	130	"pwrdm %s\n", autodep->pwrdm.ptr->name,
5b74c676 PW	131	clkdm->pwrdm.ptr->name);
d459bfe0	132
5b74c676 PW	133	pwrdm_del_sleepdep(clkdm->pwrdm.ptr, autodep->pwrdm.ptr);
5b74c676 PW	134	pwrdm_del_wkdep(clkdm->pwrdm.ptr, autodep->pwrdm.ptr);
d459bfe0 PW	135	}
	136	}
	137
a0219fbd KJ	138	/*
	139	* _omap2_clkdm_set_hwsup - set the hwsup idle transition bit
	140	* @clkdm: struct clockdomain *
	141	* @enable: int 0 to disable, 1 to enable
	142	*
	143	* Internal helper for actually switching the bit that controls hwsup
	144	* idle transitions for clkdm.
	145	*/
	146	static void _omap2_clkdm_set_hwsup(struct clockdomain *clkdm, int enable)
	147	{
	148	u32 v;
	149
	150	if (cpu_is_omap24xx()) {
	151	if (enable)
	152	v = OMAP24XX_CLKSTCTRL_ENABLE_AUTO;
	153	else
	154	v = OMAP24XX_CLKSTCTRL_DISABLE_AUTO;
	155	} else if (cpu_is_omap34xx()) {
	156	if (enable)
	157	v = OMAP34XX_CLKSTCTRL_ENABLE_AUTO;
	158	else
	159	v = OMAP34XX_CLKSTCTRL_DISABLE_AUTO;
	160	} else {
	161	BUG();
	162	}
	163
	164	cm_rmw_mod_reg_bits(clkdm->clktrctrl_mask,
	165	v << __ffs(clkdm->clktrctrl_mask),
	166	clkdm->pwrdm.ptr->prcm_offs, CM_CLKSTCTRL);
	167	}
d459bfe0 PW	168
	169	static struct clockdomain _clkdm_lookup(const char name)
	170	{
	171	struct clockdomain clkdm, temp_clkdm;
	172
	173	if (!name)
	174	return NULL;
	175
	176	clkdm = NULL;
	177
	178	list_for_each_entry(temp_clkdm, &clkdm_list, node) {
	179	if (!strcmp(name, temp_clkdm->name)) {
	180	clkdm = temp_clkdm;
	181	break;
	182	}
	183	}
	184
	185	return clkdm;
	186	}
	187
	188
	189	/* Public functions */
	190
	191	/**
	192	* clkdm_init - set up the clockdomain layer
	193	* @clkdms: optional pointer to an array of clockdomains to register
	194	* @init_autodeps: optional pointer to an array of autodeps to register
	195	*
	196	* Set up internal state. If a pointer to an array of clockdomains
	197	* was supplied, loop through the list of clockdomains, register all
	198	* that are available on the current platform. Similarly, if a
	199	* pointer to an array of clockdomain-powerdomain autodependencies was
	200	* provided, register those. No return value.
	201	*/
	202	void clkdm_init(struct clockdomain **clkdms,
	203	struct clkdm_pwrdm_autodep *init_autodeps)
	204	{
	205	struct clockdomain **c = NULL;
	206	struct clkdm_pwrdm_autodep *autodep = NULL;
	207
	208	if (clkdms)
	209	for (c = clkdms; *c; c++)
	210	clkdm_register(*c);
	211
	212	autodeps = init_autodeps;
	213	if (autodeps)
5b74c676	214	for (autodep = autodeps; autodep->pwrdm.ptr; autodep++)
d459bfe0 PW	215	_autodep_lookup(autodep);
	216	}
	217
	218	/**
	219	* clkdm_register - register a clockdomain
	220	* @clkdm: struct clockdomain * to register
	221	*
	222	* Adds a clockdomain to the internal clockdomain list.
	223	* Returns -EINVAL if given a null pointer, -EEXIST if a clockdomain is
	224	* already registered by the provided name, or 0 upon success.
	225	*/
	226	int clkdm_register(struct clockdomain *clkdm)
	227	{
	228	int ret = -EINVAL;
	229	struct powerdomain *pwrdm;
	230
	231	if (!clkdm \|\| !clkdm->name)
	232	return -EINVAL;
	233
	234	if (!omap_chip_is(clkdm->omap_chip))
	235	return -EINVAL;
	236
5b74c676	237	pwrdm = pwrdm_lookup(clkdm->pwrdm.name);
d459bfe0	238	if (!pwrdm) {
7aec53ac RK	239	pr_err("clockdomain: %s: powerdomain %s does not exist\n",
7aec53ac RK	240	clkdm->name, clkdm->pwrdm.name);
d459bfe0 PW	241	return -EINVAL;
d459bfe0 PW	242	}
5b74c676	243	clkdm->pwrdm.ptr = pwrdm;
d459bfe0 PW	244
	245	mutex_lock(&clkdm_mutex);
	246	/* Verify that the clockdomain is not already registered */
	247	if (_clkdm_lookup(clkdm->name)) {
	248	ret = -EEXIST;
	249	goto cr_unlock;
7aec53ac	250	}
d459bfe0 PW	251
	252	list_add(&clkdm->node, &clkdm_list);
	253
8420bb13 PW	254	pwrdm_add_clkdm(pwrdm, clkdm);
8420bb13 PW	255
d459bfe0 PW	256	pr_debug("clockdomain: registered %s\n", clkdm->name);
	257	ret = 0;
	258
	259	cr_unlock:
	260	mutex_unlock(&clkdm_mutex);
	261
	262	return ret;
	263	}
	264
	265	/**
	266	* clkdm_unregister - unregister a clockdomain
	267	* @clkdm: struct clockdomain * to unregister
	268	*
	269	* Removes a clockdomain from the internal clockdomain list. Returns
	270	* -EINVAL if clkdm argument is NULL.
	271	*/
	272	int clkdm_unregister(struct clockdomain *clkdm)
	273	{
	274	if (!clkdm)
	275	return -EINVAL;
	276
5b74c676	277	pwrdm_del_clkdm(clkdm->pwrdm.ptr, clkdm);
8420bb13	278
d459bfe0 PW	279	mutex_lock(&clkdm_mutex);
	280	list_del(&clkdm->node);
	281	mutex_unlock(&clkdm_mutex);
	282
	283	pr_debug("clockdomain: unregistered %s\n", clkdm->name);
	284
	285	return 0;
	286	}
	287
	288	/**
	289	* clkdm_lookup - look up a clockdomain by name, return a pointer
	290	* @name: name of clockdomain
	291	*
	292	* Find a registered clockdomain by its name. Returns a pointer to the
	293	* struct clockdomain if found, or NULL otherwise.
	294	*/
	295	struct clockdomain clkdm_lookup(const char name)
	296	{
	297	struct clockdomain clkdm, temp_clkdm;
	298
	299	if (!name)
	300	return NULL;
	301
	302	clkdm = NULL;
	303
	304	mutex_lock(&clkdm_mutex);
	305	list_for_each_entry(temp_clkdm, &clkdm_list, node) {
	306	if (!strcmp(name, temp_clkdm->name)) {
	307	clkdm = temp_clkdm;
	308	break;
	309	}
	310	}
	311	mutex_unlock(&clkdm_mutex);
	312
	313	return clkdm;
	314	}
	315
	316	/**
	317	* clkdm_for_each - call function on each registered clockdomain
	318	* @fn: callback function *
	319	*
	320	* Call the supplied function for each registered clockdomain.
	321	* The callback function can return anything but 0 to bail
	322	* out early from the iterator. The callback function is called with
	323	* the clkdm_mutex held, so no clockdomain structure manipulation
	324	* functions should be called from the callback, although hardware
	325	* clockdomain control functions are fine. Returns the last return
	326	* value of the callback function, which should be 0 for success or
	327	* anything else to indicate failure; or -EINVAL if the function pointer
	328	* is null.
	329	*/
a23456e9 PDS	330	int clkdm_for_each(int (fn)(struct clockdomain clkdm, void *user),
a23456e9 PDS	331	void *user)
d459bfe0 PW	332	{
	333	struct clockdomain *clkdm;
	334	int ret = 0;
	335
	336	if (!fn)
	337	return -EINVAL;
	338
	339	mutex_lock(&clkdm_mutex);
	340	list_for_each_entry(clkdm, &clkdm_list, node) {
a23456e9	341	ret = (*fn)(clkdm, user);
d459bfe0 PW	342	if (ret)
	343	break;
	344	}
	345	mutex_unlock(&clkdm_mutex);
	346
	347	return ret;
	348	}
	349
	350
e89087c9 PW	351	/**
	352	* clkdm_get_pwrdm - return a ptr to the pwrdm that this clkdm resides in
	353	* @clkdm: struct clockdomain *
	354	*
	355	* Return a pointer to the struct powerdomain that the specified clockdomain
	356	* 'clkdm' exists in, or returns NULL if clkdm argument is NULL.
	357	*/
	358	struct powerdomain clkdm_get_pwrdm(struct clockdomain clkdm)
	359	{
	360	if (!clkdm)
	361	return NULL;
	362
5b74c676	363	return clkdm->pwrdm.ptr;
e89087c9 PW	364	}
	365
	366
d459bfe0 PW	367	/* Hardware clockdomain control */
	368
	369	/**
	370	* omap2_clkdm_clktrctrl_read - read the clkdm's current state transition mode
	371	* @clk: struct clk * of a clockdomain
	372	*
	373	* Return the clockdomain's current state transition mode from the
	374	* corresponding domain CM_CLKSTCTRL register. Returns -EINVAL if clk
	375	* is NULL or the current mode upon success.
	376	*/
	377	static int omap2_clkdm_clktrctrl_read(struct clockdomain *clkdm)
	378	{
	379	u32 v;
	380
	381	if (!clkdm)
	382	return -EINVAL;
	383
5b74c676	384	v = cm_read_mod_reg(clkdm->pwrdm.ptr->prcm_offs, CM_CLKSTCTRL);
d459bfe0 PW	385	v &= clkdm->clktrctrl_mask;
	386	v >>= __ffs(clkdm->clktrctrl_mask);
	387
	388	return v;
	389	}
	390
	391	/**
	392	* omap2_clkdm_sleep - force clockdomain sleep transition
	393	* @clkdm: struct clockdomain *
	394	*
	395	* Instruct the CM to force a sleep transition on the specified
	396	* clockdomain 'clkdm'. Returns -EINVAL if clk is NULL or if
	397	* clockdomain does not support software-initiated sleep; 0 upon
	398	* success.
	399	*/
	400	int omap2_clkdm_sleep(struct clockdomain *clkdm)
	401	{
	402	if (!clkdm)
	403	return -EINVAL;
	404
	405	if (!(clkdm->flags & CLKDM_CAN_FORCE_SLEEP)) {
	406	pr_debug("clockdomain: %s does not support forcing "
	407	"sleep via software\n", clkdm->name);
	408	return -EINVAL;
	409	}
	410
	411	pr_debug("clockdomain: forcing sleep on %s\n", clkdm->name);
	412
	413	if (cpu_is_omap24xx()) {
	414
	415	cm_set_mod_reg_bits(OMAP24XX_FORCESTATE,
5b74c676	416	clkdm->pwrdm.ptr->prcm_offs, PM_PWSTCTRL);
d459bfe0 PW	417
	418	} else if (cpu_is_omap34xx()) {
	419
	420	u32 v = (OMAP34XX_CLKSTCTRL_FORCE_SLEEP <<
	421	__ffs(clkdm->clktrctrl_mask));
	422
	423	cm_rmw_mod_reg_bits(clkdm->clktrctrl_mask, v,
5b74c676	424	clkdm->pwrdm.ptr->prcm_offs, CM_CLKSTCTRL);
d459bfe0 PW	425
	426	} else {
	427	BUG();
	428	};
	429
	430	return 0;
	431	}
	432
	433	/**
	434	* omap2_clkdm_wakeup - force clockdomain wakeup transition
	435	* @clkdm: struct clockdomain *
	436	*
	437	* Instruct the CM to force a wakeup transition on the specified
	438	* clockdomain 'clkdm'. Returns -EINVAL if clkdm is NULL or if the
	439	* clockdomain does not support software-controlled wakeup; 0 upon
	440	* success.
	441	*/
	442	int omap2_clkdm_wakeup(struct clockdomain *clkdm)
	443	{
	444	if (!clkdm)
	445	return -EINVAL;
	446
	447	if (!(clkdm->flags & CLKDM_CAN_FORCE_WAKEUP)) {
	448	pr_debug("clockdomain: %s does not support forcing "
	449	"wakeup via software\n", clkdm->name);
	450	return -EINVAL;
	451	}
	452
	453	pr_debug("clockdomain: forcing wakeup on %s\n", clkdm->name);
	454
	455	if (cpu_is_omap24xx()) {
	456
	457	cm_clear_mod_reg_bits(OMAP24XX_FORCESTATE,
5b74c676	458	clkdm->pwrdm.ptr->prcm_offs, PM_PWSTCTRL);
d459bfe0 PW	459
	460	} else if (cpu_is_omap34xx()) {
	461
	462	u32 v = (OMAP34XX_CLKSTCTRL_FORCE_WAKEUP <<
	463	__ffs(clkdm->clktrctrl_mask));
	464
	465	cm_rmw_mod_reg_bits(clkdm->clktrctrl_mask, v,
5b74c676	466	clkdm->pwrdm.ptr->prcm_offs, CM_CLKSTCTRL);
d459bfe0 PW	467
	468	} else {
	469	BUG();
	470	};
	471
	472	return 0;
	473	}
	474
	475	/**
	476	* omap2_clkdm_allow_idle - enable hwsup idle transitions for clkdm
	477	* @clkdm: struct clockdomain *
	478	*
	479	* Allow the hardware to automatically switch the clockdomain into
	480	* active or idle states, as needed by downstream clocks. If the
	481	* clockdomain has any downstream clocks enabled in the clock
	482	* framework, wkdep/sleepdep autodependencies are added; this is so
	483	* device drivers can read and write to the device. No return value.
	484	*/
	485	void omap2_clkdm_allow_idle(struct clockdomain *clkdm)
	486	{
d459bfe0 PW	487	if (!clkdm)
	488	return;
	489
	490	if (!(clkdm->flags & CLKDM_CAN_ENABLE_AUTO)) {
	491	pr_debug("clock: automatic idle transitions cannot be enabled "
	492	"on clockdomain %s\n", clkdm->name);
	493	return;
	494	}
	495
	496	pr_debug("clockdomain: enabling automatic idle transitions for %s\n",
	497	clkdm->name);
	498
	499	if (atomic_read(&clkdm->usecount) > 0)
	500	_clkdm_add_autodeps(clkdm);
	501
a0219fbd	502	_omap2_clkdm_set_hwsup(clkdm, 1);
ba20bb12 PDS	503
ba20bb12 PDS	504	pwrdm_clkdm_state_switch(clkdm);
d459bfe0 PW	505	}
	506
	507	/**
	508	* omap2_clkdm_deny_idle - disable hwsup idle transitions for clkdm
	509	* @clkdm: struct clockdomain *
	510	*
	511	* Prevent the hardware from automatically switching the clockdomain
	512	* into inactive or idle states. If the clockdomain has downstream
	513	* clocks enabled in the clock framework, wkdep/sleepdep
	514	* autodependencies are removed. No return value.
	515	*/
	516	void omap2_clkdm_deny_idle(struct clockdomain *clkdm)
	517	{
d459bfe0 PW	518	if (!clkdm)
	519	return;
	520
	521	if (!(clkdm->flags & CLKDM_CAN_DISABLE_AUTO)) {
	522	pr_debug("clockdomain: automatic idle transitions cannot be "
	523	"disabled on %s\n", clkdm->name);
	524	return;
	525	}
	526
	527	pr_debug("clockdomain: disabling automatic idle transitions for %s\n",
	528	clkdm->name);
	529
a0219fbd	530	_omap2_clkdm_set_hwsup(clkdm, 0);
d459bfe0 PW	531
	532	if (atomic_read(&clkdm->usecount) > 0)
	533	_clkdm_del_autodeps(clkdm);
	534	}
	535
	536
	537	/* Clockdomain-to-clock framework interface code */
	538
	539	/**
	540	* omap2_clkdm_clk_enable - add an enabled downstream clock to this clkdm
	541	* @clkdm: struct clockdomain *
	542	* @clk: struct clk * of the enabled downstream clock
	543	*
	544	* Increment the usecount of this clockdomain 'clkdm' and ensure that
	545	* it is awake. Intended to be called by clk_enable() code. If the
	546	* clockdomain is in software-supervised idle mode, force the
	547	* clockdomain to wake. If the clockdomain is in hardware-supervised
	548	* idle mode, add clkdm-pwrdm autodependencies, to ensure that devices
	549	* in the clockdomain can be read from/written to by on-chip processors.
	550	* Returns -EINVAL if passed null pointers; returns 0 upon success or
	551	* if the clockdomain is in hwsup idle mode.
	552	*/
	553	int omap2_clkdm_clk_enable(struct clockdomain clkdm, struct clk clk)
	554	{
	555	int v;
	556
	557	/*
	558	* XXX Rewrite this code to maintain a list of enabled
	559	* downstream clocks for debugging purposes?
	560	*/
	561
98bb1551	562	if (!clkdm \|\| !clk \|\| !clkdm->clktrctrl_mask)
d459bfe0 PW	563	return -EINVAL;
	564
	565	if (atomic_inc_return(&clkdm->usecount) > 1)
	566	return 0;
	567
	568	/* Clockdomain now has one enabled downstream clock */
	569
	570	pr_debug("clockdomain: clkdm %s: clk %s now enabled\n", clkdm->name,
	571	clk->name);
	572
	573	v = omap2_clkdm_clktrctrl_read(clkdm);
	574
	575	if ((cpu_is_omap34xx() && v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) \|\|
a0219fbd KJ	576	(cpu_is_omap24xx() && v == OMAP24XX_CLKSTCTRL_ENABLE_AUTO)) {
	577	/* Disable HW transitions when we are changing deps */
	578	_omap2_clkdm_set_hwsup(clkdm, 0);
d459bfe0	579	_clkdm_add_autodeps(clkdm);
a0219fbd KJ	580	_omap2_clkdm_set_hwsup(clkdm, 1);
a0219fbd KJ	581	} else {
d459bfe0	582	omap2_clkdm_wakeup(clkdm);
a0219fbd	583	}
d459bfe0	584
054ce503	585	pwrdm_wait_transition(clkdm->pwrdm.ptr);
fe617af7	586	pwrdm_clkdm_state_switch(clkdm);
054ce503	587
d459bfe0 PW	588	return 0;
	589	}
	590
	591	/**
	592	* omap2_clkdm_clk_disable - remove an enabled downstream clock from this clkdm
	593	* @clkdm: struct clockdomain *
	594	* @clk: struct clk * of the disabled downstream clock
	595	*
	596	* Decrement the usecount of this clockdomain 'clkdm'. Intended to be
	597	* called by clk_disable() code. If the usecount goes to 0, put the
	598	* clockdomain to sleep (software-supervised mode) or remove the
	599	* clkdm-pwrdm autodependencies (hardware-supervised mode). Returns
	600	* -EINVAL if passed null pointers; -ERANGE if the clkdm usecount
	601	* underflows and debugging is enabled; or returns 0 upon success or
	602	* if the clockdomain is in hwsup idle mode.
	603	*/
	604	int omap2_clkdm_clk_disable(struct clockdomain clkdm, struct clk clk)
	605	{
	606	int v;
	607
	608	/*
	609	* XXX Rewrite this code to maintain a list of enabled
	610	* downstream clocks for debugging purposes?
	611	*/
	612
98bb1551	613	if (!clkdm \|\| !clk \|\| !clkdm->clktrctrl_mask)
d459bfe0 PW	614	return -EINVAL;
	615
	616	#ifdef DEBUG
	617	if (atomic_read(&clkdm->usecount) == 0) {
	618	WARN_ON(1); /* underflow */
	619	return -ERANGE;
	620	}
	621	#endif
	622
	623	if (atomic_dec_return(&clkdm->usecount) > 0)
	624	return 0;
	625
	626	/* All downstream clocks of this clockdomain are now disabled */
	627
	628	pr_debug("clockdomain: clkdm %s: clk %s now disabled\n", clkdm->name,
	629	clk->name);
	630
	631	v = omap2_clkdm_clktrctrl_read(clkdm);
	632
	633	if ((cpu_is_omap34xx() && v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) \|\|
a0219fbd KJ	634	(cpu_is_omap24xx() && v == OMAP24XX_CLKSTCTRL_ENABLE_AUTO)) {
	635	/* Disable HW transitions when we are changing deps */
	636	_omap2_clkdm_set_hwsup(clkdm, 0);
d459bfe0	637	_clkdm_del_autodeps(clkdm);
a0219fbd KJ	638	_omap2_clkdm_set_hwsup(clkdm, 1);
a0219fbd KJ	639	} else {
d459bfe0	640	omap2_clkdm_sleep(clkdm);
a0219fbd	641	}
d459bfe0	642
fe617af7 PDS	643	pwrdm_clkdm_state_switch(clkdm);
fe617af7 PDS	644
d459bfe0 PW	645	return 0;
	646	}
	647