From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mason <slash.tmp@free.fr>
Subject: Re: [RFC/NOT FOR MERGING] HACK: add global/private timers for A9
Date: Thu, 04 Jun 2015 23:00:06 +0200
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To: Felipe Balbi <balbi@ti.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>, Shawn Guo <shawn.guo@linaro.org>, Russell King <linux@arm.linux.org.uk>, Arnd Bergmann <arnd@arndb.de>, Tony Lindgren <tony@atomide.com>, Linux OMAP <linux-omap@vger.kernel.org>, Linux ARM <linux-arm-kernel@lists.infradead.org>

On 04/06/2015 22:37, Felipe Balbi wrote:
> On Thu, Jun 04, 2015 at 10:32:40PM +0200, Mason wrote:
>> On 04/06/2015 22:08, Felipe Balbi wrote:
>>
>>> On Thu, Jun 04, 2015 at 11:46:59AM +0200, Mason wrote:
>>>> Also, check /proc/timer_list for a "Broadcast device". If you don't
>>>> define one, the TWD timers are set to periodic mode, with hrtimers
>>>> disabled.
>>>
>>> Did you manage to turn global timer into Broadcast device ?
>>
>> Disclaimer: I am a kernel noob, take everything I say with
>> a rock of salt.
>>
>> As far as I can see, the global timer code doesn't handle
>> frequency changes, whereas the TWD code does.
> 
> All right, but TWD has C3STOP and that prevents it from being used as
> broadcast device.

AFAICT, my platform doesn't stop the local timers in low-power
mode, so I just dropped the CLOCK_EVT_FEAT_C3STOP flag.

There's even a patch approved by Arnd somewhere in the thread,
although he did recommend I should investigate to understand
the problem better.

Regards.