From: Mark Rutland <firstname.lastname@example.org> To: Stephen Boyd <email@example.com> Cc: "firstname.lastname@example.org" <email@example.com>, "firstname.lastname@example.org" <email@example.com>, "firstname.lastname@example.org" <email@example.com>, John Stultz <firstname.lastname@example.org>, Thomas Gleixner <email@example.com> Subject: Re: [PATCHv3 01/10] clocksource: add generic dummy timer driver Date: Fri, 22 Mar 2013 18:03:05 +0000 Message-ID: <20130322180305.GB1436@e106331-lin.cambridge.arm.com> (raw) In-Reply-To: <514B4DBD.firstname.lastname@example.org> On Thu, Mar 21, 2013 at 06:13:17PM +0000, Stephen Boyd wrote: > On 03/21/13 11:09, Mark Rutland wrote: > > Hi Stephen, > > > > I've just been trying to test the dummy timer, and realised it's broken, as it > > registers a cpu notifier from a device_initcall (after SMP's been brought up), > > and doesn't ensure all active CPUs have been set up. Evidently no-one else has > > attempted to test it thus far, and I'm not able to throughly test it at the > > moment. > > Would it be sufficient to register as a pre-smp initcall? I've looked a bit further into the problem, and I believe using early_initcall will make it work as well as the current arm-specific dummy timers work with a rating of 100 (this means the recent patch lowering the rating broke tc2 as explained below). I've spent the last few hours trying to get the dummy_timer driver working on tc2 with the sp804 as the broadcast source (with architected timer support disabled). It turns out that having dummy timer's rating so low means that it won't be selected as the tick device on cpu0 in preference to the sp804, and thus won't push the sp804 out of that spot (allowing it to become the broadcast source). This leads to boot stalling. Jumping the dummy_timer's rating up would fix this, but that doesn't seem great. Registering the dummy before all other clocks would also fix this (I tried calling dummy_timer_register from time_init), but I can't see a way to do that while keeping the driver self-contained. Thanks, Mark.
next prev parent reply index Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top 2013-03-13 18:17 [PATCHv3 00/10] Remove ARM local timer API Stephen Boyd 2013-03-13 18:17 ` [PATCHv3 01/10] clocksource: add generic dummy timer driver Stephen Boyd 2013-03-21 18:09 ` Mark Rutland 2013-03-21 18:13 ` Stephen Boyd 2013-03-22 18:03 ` Mark Rutland [this message] 2013-03-25 16:49 ` Stephen Boyd 2013-03-25 18:00 ` Mark Rutland 2013-03-25 20:47 ` Thomas Gleixner 2013-03-26 15:26 ` Mark Rutland 2013-03-26 2:14 ` Stephen Boyd 2013-03-26 11:28 ` Mark Rutland 2013-04-05 1:46 ` Stephen Boyd 2013-03-13 18:17 ` [PATCHv3 02/10] ARM: smp: Remove duplicate dummy timer implementation Stephen Boyd 2013-03-13 18:17 ` [PATCHv3 03/10] ARM: smp_twd: Divorce smp_twd from local timer API Stephen Boyd 2013-03-28 15:22 ` Mark Rutland 2013-03-28 20:09 ` Stephen Boyd 2013-04-02 8:41 ` Mark Rutland 2013-03-13 18:17 ` [PATCHv3 04/10] ARM: OMAP2+: Divorce " Stephen Boyd 2013-03-13 18:17 ` [PATCHv3 05/10] ARM: EXYNOS4: Divorce mct " Stephen Boyd 2013-03-13 18:17 ` [PATCHv3 06/10] ARM: PRIMA2: Divorce timer-marco " Stephen Boyd 2013-03-13 18:17 ` [PATCHv3 07/10] ARM: msm: Divorce msm_timer " Stephen Boyd 2013-03-13 18:17 ` [PATCHv3 08/10] clocksource: time-armada-370-xp: Fix sparse warning Stephen Boyd 2013-03-20 17:06 ` Gregory CLEMENT 2013-03-13 18:17 ` [PATCHv3 09/10] clocksource: time-armada-370-xp: Divorce from local timer API Stephen Boyd 2013-03-20 17:09 ` Gregory CLEMENT 2013-03-20 17:20 ` Stephen Boyd 2013-03-20 17:26 ` Gregory CLEMENT 2013-03-20 17:44 ` Gregory CLEMENT 2013-03-20 18:00 ` Stephen Boyd 2013-03-20 17:21 ` Gregory CLEMENT 2013-03-13 18:17 ` [PATCHv3 10/10] ARM: smp: Remove " Stephen Boyd
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20130322180305.GB1436@e106331-lin.cambridge.arm.com \ --email@example.com \ --firstname.lastname@example.org \ --email@example.com \ --firstname.lastname@example.org \ --email@example.com \ --firstname.lastname@example.org \ --email@example.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: link
Linux-ARM-MSM Archive on lore.kernel.org Archives are clonable: git clone --mirror https://lore.kernel.org/linux-arm-msm/0 linux-arm-msm/git/0.git # If you have public-inbox 1.1+ installed, you may # initialize and index your mirror using the following commands: public-inbox-init -V2 linux-arm-msm linux-arm-msm/ https://lore.kernel.org/linux-arm-msm \ firstname.lastname@example.org public-inbox-index linux-arm-msm Example config snippet for mirrors Newsgroup available over NNTP: nntp://nntp.lore.kernel.org/org.kernel.vger.linux-arm-msm AGPL code for this site: git clone https://public-inbox.org/public-inbox.git