Re: [Letux-kernel] [PATCH v3 3/3] arm: omap_hwmod disable ick autoidling when a hwmod requires that

From: Keerthy <j-keerthy@ti.com>
To: Andreas Kemnade <andreas@kemnade.info>
Cc: Tony Lindgren <tony@atomide.com>,
	Discussions about the Letux Kernel 
	<letux-kernel@openphoenux.org>, <paul@pwsan.com>,
	<sboyd@kernel.org>, <mturquette@baylibre.com>,
	<linux-kernel@vger.kernel.org>, <t-kristo@ti.com>,
	<bcousson@baylibre.com>, <linux-omap@vger.kernel.org>,
	<linux-clk@vger.kernel.org>
Subject: Re: [Letux-kernel] [PATCH v3 3/3] arm: omap_hwmod disable ick autoidling when a hwmod requires that
Date: Tue, 22 Jan 2019 11:56:01 +0530	[thread overview]
Message-ID: <f7a46583-b6ac-a125-c8ab-e36fa80fe693@ti.com> (raw)
In-Reply-To: <dd7f4d9f-4036-5fc2-995e-c3dae6e69aff@ti.com>

On 19/01/19 1:28 PM, J, KEERTHY wrote:
> 
> 
> On 1/19/2019 12:42 PM, Andreas Kemnade wrote:
>> On Sat, 19 Jan 2019 12:09:48 +0530
>> "J, KEERTHY" <j-keerthy@ti.com> wrote:
>>
>>> On 1/19/2019 1:18 AM, Tony Lindgren wrote:
>>>> * Andreas Kemnade <andreas@kemnade.info> [190118 19:42]:
>>>>> On Fri, 18 Jan 2019 20:38:47 +0100
>>>>> Andreas Kemnade <andreas@kemnade.info> wrote:
>>>>>  
>>>>>> Hi,
>>>>>>
>>>>>> On Fri, 18 Jan 2019 10:36:30 -0800
>>>>>> Tony Lindgren <tony@atomide.com> wrote:
>>>>>>
>>>>>> [...]
>>>>>>> til the next workaround.
>>>>>>>      
>>>>>>>> That flags also causes the iclk being enabled/disabled
>>>>>>>> manually.
>>>>>>>
>>>>>>> Yes but SWSUP_IDLE for the interface clock to me currently
>>>>>>> just means:
>>>>>>>
>>>>>>> "manually enable and disable ocp interface clock"
>>>>>>>       
>>>>>> well, if we want to manually disable it and not automatically,
>>>>>> we have to disable autoidle or it will be automatically disabled.
>>>>>>
>>>>>> Disabling it manually when it is already auto-disabled (by
>>>>>> autoidle) is
>>>>>> just practically a no-op towards the clock.
>>>>>>  
>>>>>>> and with your changes it becomes:
>>>>>>>
>>>>>>> "manually enable and disable ocp interface clock and block
>>>>>>>    autoidle while in use".
>>>>>>>
>>>>>>> So aren't we now changing the way things behave in general
>>>>>>> for SWSUP_IDLE?
>>>>>>>       
>>>>>> Yes, we are, so proper testing is needed. But If I read those
>>>>>> comments
>>>>>> it was always intended this way but not fully implemented because it
>>>>>> appeared to be more work like needing a usecounter (which my patchset
>>>>>> also adds) for that autoidle flag.
>>>>>>   
>>>>> and there are quite few hwmods marked by this flag.
>>>>> And then there are those clocks marked by this flags (on am33xx) which
>>>>> do not have that autoidle feature at all, so the risk is not too high.
>>>>
>>>> Keerthy, can you please test this series on top of the
>>>> related clock patches with your am335x PM test cases?
>>>
>>> Can you point me to the clock series that needs to be tested
>>> along with this?
>>>
>>
>> https://patchwork.kernel.org/project/linux-clk/list/?series=66691
> 
> Thanks Andreas. I will test both series and get back.

Tested for DS0 (deeps sleep 0 on am33/am43 boards) No issues seen with
the current patch series on top of clock series.

Tested-by: Keerthy <j-keerthy@ti.com>

> 
>>
>> Regards,
>> Andreas
>>