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From: Mason <slash.tmp@free.fr>
To: Daniel Lezcano <daniel.lezcano@linaro.org>,
	Thomas Gleixner <tglx@linutronix.de>
Cc: Marc Gonzalez <marc_gonzalez@sigmadesigns.com>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] clocksource/drivers/tango_xtal: Add new timer for Tango SoCs
Date: Wed, 7 Oct 2015 22:12:41 +0200	[thread overview]
Message-ID: <56157CB9.7010105@free.fr> (raw)
In-Reply-To: <56154268.5060700@linaro.org>

On 07/10/2015 18:03, Daniel Lezcano wrote:

> On 10/07/2015 03:17 PM, Marc Gonzalez wrote:
>
>> I'm also confused that you've replaced panic() with pr_err/return.
>> AFAIU, if I don't have a clocksource/sched_clock, the system is dead
>> in the water. Might as well stop there, and wait for the operator to
>> fix whatever needs fixing. (Several clksrc drivers do this.)
> 
> Hmm, yeah that's true but also we have platforms with different 
> clocksources, so we don't want to panic if the next clocksource will 
> succeed. That's the logic behind not doing panic. There is some legacy 
> code still using panic but that should be fixed.

There's so much legacy code lying around that it's really hard
to tell what the current best practices are :-(

> I don't know if your platform can fall under this category, but it would 
> be a good practice to pr_err or pr_warn instead of panic in order to be 
> consistent with the current direction in the recent drivers.

I think the system falls back to using the "jiffies clock" when
it doesn't find anything better? However, on my system, the
clockevent device is running at cpuclk/2, so once I add cpufreq
DFS into the mix, I don't think the "jiffies" clock is a very
good clocksource.

Anyway, updated patch is on the way.

Regards.


  reply	other threads:[~2015-10-08 13:15 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-10-06 15:10 [PATCH v1] clocksource: Sigma Designs Tango 27 MHz xtal Marc Gonzalez
2015-10-06 23:09 ` Daniel Lezcano
2015-10-07  8:23   ` Marc Gonzalez
2015-10-07  9:47     ` Daniel Lezcano
2015-10-07 11:14       ` Marc Gonzalez
2015-10-07 11:35         ` Daniel Lezcano
2015-10-07 11:35     ` [PATCH v2] clocksource/drivers/tango_xtal: Add new timer for Tango SoCs Marc Gonzalez
2015-10-07 12:31       ` Daniel Lezcano
2015-10-07 13:17         ` Marc Gonzalez
2015-10-07 16:03           ` Daniel Lezcano
2015-10-07 20:12             ` Mason [this message]
2015-10-09 12:13               ` [PATCH v3] " Marc Gonzalez
2015-10-09 13:24                 ` Daniel Lezcano
2015-10-09 13:46                   ` Marc Gonzalez
2015-10-09 14:21                     ` Daniel Lezcano
2015-10-09 16:39                       ` Nicolas Pitre
2015-10-09 14:37                   ` [PATCH v4] " Marc Gonzalez
2015-10-09 14:42                     ` Daniel Lezcano
2015-10-09 14:59                       ` [PATCH v5] " Marc Gonzalez
2015-10-16 12:07                         ` Daniel Lezcano
2015-10-09 14:51                     ` [PATCH v4] " Måns Rullgård
2015-10-09 15:42                       ` Marc Gonzalez
2015-10-09 16:01                         ` Måns Rullgård
2015-10-09 16:36                           ` Marc Gonzalez

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