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

From: "J, 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: Sat, 19 Jan 2019 13:28:38 +0530	[thread overview]
Message-ID: <dd7f4d9f-4036-5fc2-995e-c3dae6e69aff@ti.com> (raw)
In-Reply-To: <20190119081211.73844b6a@aktux>

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.

> 
> Regards,
> Andreas
> 