Hi,
On Tue, 8 Mar 2011, Kevin Hilman wrote:
> Kalle Jokiniemi <kalle.jokiniemi@xxxxxxxxx> writes:
>
> > The runtime PM does not offer enough granularity to control
> > individual clocks separately as needed. Current pm implementation
> > of omap_wdt blocks the CORE power domain from idling in
> > OMAP SoC, as it keeps the interface clock of the watchdog always
> > on. This causes severe power leakage in devices where
> > the omap watchdog is in active use.
>
> The iclk remains active because it's in hardware-controlled
> auto-idle mode.
... and we think that the interface clock never enters auto-idle because
the WDT doesn't SIdleAck to the PRCM until the special sequence has been
written to the WDT registers to disable it. So even if its *CLKEN bits
are set to zero, the WDT prevents the system from going idle.
> I believe if you set the WDT hwmod to software-supported idle
> (OCPIF_SWSUP_IDLE), the runtime PM idle (which calls omap_device idle,
> then omap_hwmod_idle) should also gate the interface clock.
Agreed.
Kalle, since you requested patches, here's one that implements Kevin's
first suggestion. I will reply to your second patch with its equivalent
for PM runtime. The patches have been compile-tested only. Perhaps you
could see if they solve your problem?
regards,
- Paul
---
arch/arm/mach-omap2/omap_hwmod_2420_data.c | 1 +
arch/arm/mach-omap2/omap_hwmod_2430_data.c | 1 +
arch/arm/mach-omap2/omap_hwmod_3xxx_data.c | 1 +
arch/arm/mach-omap2/omap_hwmod_44xx_data.c | 1 +
4 files changed, 4 insertions(+), 0 deletions(-)
diff --git a/arch/arm/mach-omap2/omap_hwmod_2420_data.c b/arch/arm/mach-omap2/omap_hwmod_2420_data.c
index 1611f74..df4950d 100644
--- a/arch/arm/mach-omap2/omap_hwmod_2420_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_2420_data.c
@@ -974,6 +974,7 @@ static struct omap_hwmod_ocp_if omap2420_l4_wkup__wd_timer2 = {
.clk = "mpu_wdt_ick",
.addr = omap2420_wd_timer2_addrs,
.addr_cnt = ARRAY_SIZE(omap2420_wd_timer2_addrs),
+ .flags = OCPIF_SWSUP_IDLE,
.user = OCP_USER_MPU | OCP_USER_SDMA,
};
diff --git a/arch/arm/mach-omap2/omap_hwmod_2430_data.c b/arch/arm/mach-omap2/omap_hwmod_2430_data.c
index 809424f..21fc908 100644
--- a/arch/arm/mach-omap2/omap_hwmod_2430_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_2430_data.c
@@ -1074,6 +1074,7 @@ static struct omap_hwmod_ocp_if omap2430_l4_wkup__wd_timer2 = {
.clk = "mpu_wdt_ick",
.addr = omap2430_wd_timer2_addrs,
.addr_cnt = ARRAY_SIZE(omap2430_wd_timer2_addrs),
+ .flags = OCPIF_SWSUP_IDLE,
.user = OCP_USER_MPU | OCP_USER_SDMA,
};
diff --git a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
index 457df3e..7ae2dab 100644
--- a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
@@ -1234,6 +1234,7 @@ static struct omap_hwmod_ocp_if omap3xxx_l4_wkup__wd_timer2 = {
.clk = "wdt2_ick",
.addr = omap3xxx_wd_timer2_addrs,
.addr_cnt = ARRAY_SIZE(omap3xxx_wd_timer2_addrs),
+ .flags = OCPIF_SWSUP_IDLE,
.user = OCP_USER_MPU | OCP_USER_SDMA,
};
diff --git a/arch/arm/mach-omap2/omap_hwmod_44xx_data.c b/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
index 7b72316..2038813 100644
--- a/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
@@ -4901,6 +4901,7 @@ static struct omap_hwmod_ocp_if omap44xx_l4_wkup__wd_timer2 = {
.clk = "l4_wkup_clk_mux_ck",
.addr = omap44xx_wd_timer2_addrs,
.addr_cnt = ARRAY_SIZE(omap44xx_wd_timer2_addrs),
+ .flags = OCPIF_SWSUP_IDLE,
.user = OCP_USER_MPU | OCP_USER_SDMA,
};
--
1.7.2.3
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