[QUESTION] How to set static/dynamic dependency between clock domains

[Shilimkar, Santosh]

On Fri, Dec 23, 2011 at 2:00 PM, Ming Lei <tom.leiming at gmail.com> wrote:
> Hi Shilimkar,
>
> Sorry for the delay.
>
> On Mon, Dec 19, 2011 at 2:17 PM, Shilimkar, Santosh
> <santosh.shilimkar at ti.com> wrote:
>
>> The patches are fine but I am surprised that 'dyndep.patch' is helping you.
>> L3_2 dependency is always enabled with ISS or Camera and it
>> should have worked.
>> clkdm_add_wkdep(iss_clkdm, l3_2_clkdm), shoudn't do anything since
>> the bit is read-only.
>
> Yes, you are right. After some investigating, I found that
> clkdm_add_wkdep(iss_clkdm, l3_2_clkdm) returns failure, so clkdms_setup
> is bypassed and the issue is avoided.
>
Good.

>>
>> Can you check value of CM_CAM_STATICDEP [ 0x4A009004],
>
> The value is 0x40 after and before the patch.
>
>> after your patch. I am suspecting that for some reason l3_1 dep.
>> is getting enabled which might be helping your case.
>
> Seems no changes after adding clkdm_add_wkdep(iss_clkdm, l3_1_clkdm)
> on the problem.
>
> The only change on iss(CAM) clock domain setting in your commit[1] is to
> configure CLKTRCTRL as HW_AUTO, instead of previous  SW_WKUP.
> Once I change flags of iss to CLKDM_CAN_SWSUP [2], the issue can be
> fixed, so I am wondering if something is wrong about HW_AUTO mode
> of CAM clock domain.
>
Now I recollect the issue and also track a patch in the internal product tree.
Same is attached and also in the end of the email.

I am lopping Miguel who wrote the patch and Benoit who acked it.
This should sort out your issue as you have already verified it works.

Regards
Santosh

>From 972d7bb544d3197d7fc1a6c6eb0e2c9cc08d5e9d Mon Sep 17 00:00:00 2001
From: Miguel Vadillo <vadillo at ti.com>
Date: Tue, 21 Jun 2011 09:59:45 -0500
Subject: [PATCH 1/2] OMAP: clockdomain: set iss clk domain to just SWSUP

Since CAM domain(ISS) has no module wake-up dependency
with any other clock domain of the device and the dynamic
dependency from L3_main_2 is always disabled, the domain
needs to be in force wakeup in order to be able to access
it for configure(sysconfig) it or use it.

Also since there is no clock in the domain managed automatically
by the hardware, there is no use to configure automatic
clock domain transition. SW should keep the SW_WKUP domain
transition as long as a module in the domain is required to
be functional.

Signed-off-by: Miguel Vadillo <vadillo at ti.com>
Acked-by: Benoit Cousson<b-cousson at ti.com>
---
 arch/arm/mach-omap2/clockdomains44xx_data.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/arm/mach-omap2/clockdomains44xx_data.c
b/arch/arm/mach-omap2/clockdomains44xx_data.c
index 6ac8fe2..8d1a061 100644
--- a/arch/arm/mach-omap2/clockdomains44xx_data.c
+++ b/arch/arm/mach-omap2/clockdomains44xx_data.c
@@ -605,7 +605,7 @@ static struct clockdomain iss_44xx_clkdm = {
 	.clkdm_offs	  = OMAP4430_CM2_CAM_CAM_CDOFFS,
 	.wkdep_srcs	  = iss_wkup_sleep_deps,
 	.sleepdep_srcs	  = iss_wkup_sleep_deps,
-	.flags		  = CLKDM_CAN_HWSUP_SWSUP,
+	.flags		  = CLKDM_CAN_SWSUP,
 	.omap_chip	  = OMAP_CHIP_INIT(CHIP_IS_OMAP44XX),
 };

-- 
1.7.4.1
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