OMAP: clockdomain: Wait for powerdomain to be ON when using clockdomain force wakeup

While using clockdomain force wakeup method, not waiting for powerdomain
to be effectively ON may end up locking the clockdomain FSM until a
next wakeup event occurs.

One such issue was seen on OMAP4430, where L4_PER was periodically
getting stuck in in-transition state when transitioning from from OSWR to ON.

This issue was reported and investigated by Patrick Titiano <p-titiano@ti.com>

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Reported-by: Patrick Titiano <p-titiano@ti.com>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
[paul@pwsan.com: updated to apply; added transition wait on clkdm_deny_idle();
 remove two superfluous pwrdm_wait_transition() calls]
Signed-off-by: Paul Walmsley <paul@pwsan.com>

diff --git a/arch/arm/mach-omap2/clockdomain.c b/arch/arm/mach-omap2/clockdomain.c
index ab7db083f97fda3ffa9b6b5b419ae321878bc6ed..8f0890685d7b10f7f594e9cd44c8a972c33d15e9 100644 (file)
--- a/arch/arm/mach-omap2/clockdomain.c
+++ b/arch/arm/mach-omap2/clockdomain.c
@@ -747,6 +747,7 @@ int clkdm_wakeup(struct clockdomain *clkdm)
        spin_lock_irqsave(&clkdm->lock, flags);
        clkdm->_flags &= ~_CLKDM_FLAG_HWSUP_ENABLED;
        ret = arch_clkdm->clkdm_wakeup(clkdm);
+       ret |= pwrdm_state_switch(clkdm->pwrdm.ptr);
        spin_unlock_irqrestore(&clkdm->lock, flags);
        return ret;
 }
@@ -818,6 +819,7 @@ void clkdm_deny_idle(struct clockdomain *clkdm)
        spin_lock_irqsave(&clkdm->lock, flags);
        clkdm->_flags &= ~_CLKDM_FLAG_HWSUP_ENABLED;
        arch_clkdm->clkdm_deny_idle(clkdm);
+       pwrdm_state_switch(clkdm->pwrdm.ptr);
        spin_unlock_irqrestore(&clkdm->lock, flags);
 }
 

diff --git a/arch/arm/mach-omap2/pm.c b/arch/arm/mach-omap2/pm.c
index 3feb35911a325576bf7a6f57892adbcccbeda853..472bf22d5e84875416854c3e76c206fa02c85302 100644 (file)
--- a/arch/arm/mach-omap2/pm.c
+++ b/arch/arm/mach-omap2/pm.c
@@ -130,7 +130,6 @@ int omap_set_pwrdm_state(struct powerdomain *pwrdm, u32 state)
                } else {
                        hwsup = clkdm_in_hwsup(pwrdm->pwrdm_clkdms[0]);
                        clkdm_wakeup(pwrdm->pwrdm_clkdms[0]);
-                       pwrdm_wait_transition(pwrdm);
                        sleep_switch = FORCEWAKEUP_SWITCH;
                }
        }
@@ -156,7 +155,6 @@ int omap_set_pwrdm_state(struct powerdomain *pwrdm, u32 state)
                return ret;
        }
 
-       pwrdm_wait_transition(pwrdm);
        pwrdm_state_switch(pwrdm);
 err:
        return ret;