From: Paul Walmsley <paul@xxxxxxxxx>
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@xxxxxxxxxxxxxxxxxxx> did all the really hard work on
this, identifying the problem and finding the bug.
Signed-off-by: Paul Walmsley <paul@xxxxxxxxx>
Signed-off-by: Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx>
---
arch/arm/mach-omap2/clockdomain.c | 110 +++++--------------------------------
arch/arm/mach-omap2/pm34xx.c | 3 -
2 files changed, 15 insertions(+), 98 deletions(-)
diff --git a/arch/arm/mach-omap2/clockdomain.c b/arch/arm/mach-omap2/clockdomain.c
index 5d80cb8..6fb61b1 100644
--- a/arch/arm/mach-omap2/clockdomain.c
+++ b/arch/arm/mach-omap2/clockdomain.c
@@ -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);
diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index f5f1dbd..d2b940c 100644
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -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 &&
--
1.7.2.1
--
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