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

/*
 * OMAP2/3 clockdomain framework functions
 *
 * Copyright (C) 2008 Texas Instruments, Inc.
 * Copyright (C) 2008 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.
 */
#ifdef CONFIG_OMAP_DEBUG_CLOCKDOMAIN
#  define DEBUG
#endif

#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 <mach/clock.h>

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

#include <mach/powerdomain.h>
#include <mach/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);
	}
}


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))
{
	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);
		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)
{
	u32 v;

	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);

	if (cpu_is_omap24xx())
		v = OMAP24XX_CLKSTCTRL_ENABLE_AUTO;
	else if (cpu_is_omap34xx())
		v = OMAP34XX_CLKSTCTRL_ENABLE_AUTO;
	else
		BUG();


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

	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)
{
	u32 v;

	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);

	if (cpu_is_omap24xx())
		v = OMAP24XX_CLKSTCTRL_DISABLE_AUTO;
	else if (cpu_is_omap34xx())
		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);

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