linux-kernel - Re: Enable arm_global_timer for Zynq brakes boot

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <3a4049f6-aad6-4730-86e3-210afbc3836b@DB9EHSMHS028.ehs.local>
Date:	Fri, 9 Aug 2013 10:48:05 -0700
From:	Sören Brinkmann <soren.brinkmann@...inx.com>
To:	Stephen Boyd <sboyd@...eaurora.org>
CC:	Daniel Lezcano <daniel.lezcano@...aro.org>,
	<srinivas.kandagatla@...com>,
	Russell King <linux@....linux.org.uk>,
	Michal Simek <michal.simek@...inx.com>,
	<linux-kernel@...r.kernel.org>,
	Stuart Menefy <stuart.menefy@...com>,
	John Stultz <john.stultz@...aro.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	<linux-arm-kernel@...ts.infradead.org>
Subject: Re: Enable arm_global_timer for Zynq brakes boot

On Fri, Aug 09, 2013 at 10:27:57AM -0700, Stephen Boyd wrote:
> On 08/09, Daniel Lezcano wrote:
> > 
> > yes, but at least the broadcast mechanism should send an IPI to cpu0 to
> > wake it up, no ? As Stephen stated this kind of configuration should has
> > never been tested before so the tick broadcast code is not handling this
> > case properly IMHO.
> > 
> 
> If you have a per-cpu tick device that isn't suffering from
> FEAT_C3_STOP why wouldn't you use that for the tick versus a
> per-cpu tick device that has FEAT_C3_STOP? It sounds like there
> is a bug in the preference logic or you should boost the rating
> of the arm global timer above the twd. Does this patch help? It
> should make the arm global timer the tick device and whatever the
> cadence timer you have into the broadcast device.

I'm not sure I'm getting this right. But neither the cadence_ttc nor the
arm_global_timer have the FEAT_C3_STOP flag set. So, shouldn't they be
treated equally even with your change?

	Sören


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/