Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 6f7f63cc authored by Paul Walmsley's avatar Paul Walmsley Committed by Kevin Hilman
Browse files

OMAP clockdomain: initialize clockdomain registers when the clockdomain layer starts 



When the clockdomain layer initializes, place all clockdomains into
software-supervised mode, and clear all wakeup and sleep dependencies
immediately, rather than waiting for the PM code to do this later.
This fixes a major bug where critical sleep dependencies added by the
hwmod code are cleared during late PM init.

As a side benefit, the _init_{wk,sleep}dep_usecount() functions are no
longer needed, so remove them.

Kevin Hilman <khilman@deeprootsystems.com> did all the really hard work on
this, identifying the problem and finding the bug.

Signed-off-by: default avatarPaul Walmsley <paul@pwsan.com>
Signed-off-by: default avatarKevin Hilman <khilman@deeprootsystems.com>
parent eb6a2c75

arch/arm/mach-omap2/clockdomain.c

+15 −95
Original line number Diff line number Diff line
@@ -258,97 +258,6 @@ static void _omap2_clkdm_set_hwsup(struct clockdomain *clkdm, int enable) 


}



/**

 * _init_wkdep_usecount - initialize wkdep usecounts to match hardware

 * @clkdm: clockdomain to initialize wkdep usecounts

 *

 * Initialize the wakeup dependency usecount variables for clockdomain @clkdm.

 * If a wakeup dependency is present in the hardware, the usecount will be

 * set to 1; otherwise, it will be set to 0.  Software should clear all

 * software wakeup dependencies prior to calling this function if it wishes

 * to ensure that all usecounts start at 0.  No return value.

 */

static void _init_wkdep_usecount(struct clockdomain *clkdm)

{

	u32 v;

	struct clkdm_dep *cd;



	if (!clkdm->wkdep_srcs)

		return;



	for (cd = clkdm->wkdep_srcs; cd->clkdm_name; cd++) {

		if (!omap_chip_is(cd->omap_chip))

			continue;



		if (!cd->clkdm && cd->clkdm_name)

			cd->clkdm = _clkdm_lookup(cd->clkdm_name);



		if (!cd->clkdm) {

			WARN(!cd->clkdm, "clockdomain: %s: wkdep clkdm %s not "

			     "found\n", clkdm->name, cd->clkdm_name);

			continue;

		}



		v = prm_read_mod_bits_shift(clkdm->pwrdm.ptr->prcm_offs,

					    PM_WKDEP,

					    (1 << cd->clkdm->dep_bit));



		if (v)

			pr_debug("clockdomain: %s: wakeup dependency already "

				 "set to wake up when %s wakes\n",

				 clkdm->name, cd->clkdm->name);



		atomic_set(&cd->wkdep_usecount, (v) ? 1 : 0);

	}

}



/**

 * _init_sleepdep_usecount - initialize sleepdep usecounts to match hardware

 * @clkdm: clockdomain to initialize sleepdep usecounts

 *

 * Initialize the sleep dependency usecount variables for clockdomain @clkdm.

 * If a sleep dependency is present in the hardware, the usecount will be

 * set to 1; otherwise, it will be set to 0.  Software should clear all

 * software sleep dependencies prior to calling this function if it wishes

 * to ensure that all usecounts start at 0.  No return value.

 */

static void _init_sleepdep_usecount(struct clockdomain *clkdm)

{

	u32 v;

	struct clkdm_dep *cd;



	if (!cpu_is_omap34xx())

		return;



	if (!clkdm->sleepdep_srcs)

		return;



	for (cd = clkdm->sleepdep_srcs; cd->clkdm_name; cd++) {

		if (!omap_chip_is(cd->omap_chip))

			continue;



		if (!cd->clkdm && cd->clkdm_name)

			cd->clkdm = _clkdm_lookup(cd->clkdm_name);



		if (!cd->clkdm) {

			WARN(!cd->clkdm, "clockdomain: %s: sleepdep clkdm %s "

			     "not found\n", clkdm->name, cd->clkdm_name);

			continue;

		}



		v = prm_read_mod_bits_shift(clkdm->pwrdm.ptr->prcm_offs,

					    OMAP3430_CM_SLEEPDEP,

					    (1 << cd->clkdm->dep_bit));



		if (v)

			pr_debug("clockdomain: %s: sleep dependency already "

				 "set to prevent from idling until %s "

				 "idles\n", clkdm->name, cd->clkdm->name);



		atomic_set(&cd->sleepdep_usecount, (v) ? 1 : 0);

	}

};



/* Public functions */



/**
@@ -379,12 +288,17 @@ void clkdm_init(struct clockdomain **clkdms, 
			_autodep_lookup(autodep);



	/*

	 * Ensure that the *dep_usecount registers reflect the current

	 * state of the PRCM.

	 * Put all clockdomains into software-supervised mode; PM code

	 * should later enable hardware-supervised mode as appropriate

	 */

	list_for_each_entry(clkdm, &clkdm_list, node) {

		_init_wkdep_usecount(clkdm);

		_init_sleepdep_usecount(clkdm);

		if (clkdm->flags & CLKDM_CAN_FORCE_WAKEUP)

			omap2_clkdm_wakeup(clkdm);

		else if (clkdm->flags & CLKDM_CAN_DISABLE_AUTO)

			omap2_clkdm_deny_idle(clkdm);



		clkdm_clear_all_wkdeps(clkdm);

		clkdm_clear_all_sleepdeps(clkdm);

	}

}
@@ -592,6 +506,9 @@ int clkdm_clear_all_wkdeps(struct clockdomain *clkdm) 
		if (!omap_chip_is(cd->omap_chip))

			continue;



		if (!cd->clkdm && cd->clkdm_name)

			cd->clkdm = _clkdm_lookup(cd->clkdm_name);



		/* PRM accesses are slow, so minimize them */

		mask |= 1 << cd->clkdm->dep_bit;

		atomic_set(&cd->wkdep_usecount, 0);
@@ -752,6 +669,9 @@ int clkdm_clear_all_sleepdeps(struct clockdomain *clkdm) 
		if (!omap_chip_is(cd->omap_chip))

			continue;



		if (!cd->clkdm && cd->clkdm_name)

			cd->clkdm = _clkdm_lookup(cd->clkdm_name);



		/* PRM accesses are slow, so minimize them */

		mask |= 1 << cd->clkdm->dep_bit;

		atomic_set(&cd->sleepdep_usecount, 0);

arch/arm/mach-omap2/pm34xx.c

+0 −3
Original line number Diff line number Diff line
@@ -949,9 +949,6 @@ static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused) 
 */

static int __init clkdms_setup(struct clockdomain *clkdm, void *unused)

{

	clkdm_clear_all_wkdeps(clkdm);

	clkdm_clear_all_sleepdeps(clkdm);



	if (clkdm->flags & CLKDM_CAN_ENABLE_AUTO)

		omap2_clkdm_allow_idle(clkdm);

	else if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP &&