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: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
This commit is contained in:
Paul Walmsley 2010-09-14 15:56:53 -06:00 коммит произвёл Kevin Hilman
Родитель eb6a2c7550
Коммит 6f7f63cc9a
2 изменённых файлов: 15 добавлений и 98 удалений

Просмотреть файл

@ -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);

Просмотреть файл

@ -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 &&