Linux MIPS Architecture development
 help / color / mirror / Atom feed
From: James Hogan <james.hogan@imgtec.com>
To: Ralf Baechle <ralf@linux-mips.org>
Cc: "Maciej W. Rozycki" <macro@imgtec.com>, <linux-mips@linux-mips.org>
Subject: Re: [PATCH 3/4] MIPS: malta-time: Don't use PIT timer for cevt/csrc
Date: Thu, 28 Apr 2016 17:36:43 +0100	[thread overview]
Message-ID: <20160428163643.GD2467@jhogan-linux.le.imgtec.org> (raw)
In-Reply-To: <20160422192906.GO24051@linux-mips.org>

[-- Attachment #1: Type: text/plain, Size: 1144 bytes --]

On Fri, Apr 22, 2016 at 09:29:07PM +0200, Ralf Baechle wrote:
> On Fri, Apr 22, 2016 at 08:23:12PM +0100, James Hogan wrote:
> 
> > >  Not everyone uses virtualisation, so it's a functional regression for 
> > > them.  Can't you lower the priority for the timer instead so that it is 
> > > not selected by default, just as it's done with other platforms providing 
> > > a choice of timers?
> > 
> > I'll look into that. Looking back at my IRC logs I suspect I meant to
> > check why the PIT was taking priority before submitting upstream, but
> > forgot.
> 
> The PIT already has a very low rating and should only be used if everything
> else fails.  Clock scaling for example would make the cycle counter
> unusable, there might be no GIC available etc.  Otoh with SMP the PIT is
> only usable as a clock source but not clock event device.

I can't even reproduce the problem any longer. Even with the PIT drivers
loaded and a message in the log about PIT clocksource it doesn't seem to
be used, so we can just drop this one anyway. I've marked this patch as
rejected in patchwork. Sorry for the noise.

Thanks
James

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]

WARNING: multiple messages have this Message-ID (diff)
From: James Hogan <james.hogan@imgtec.com>
To: Ralf Baechle <ralf@linux-mips.org>
Cc: "Maciej W. Rozycki" <macro@imgtec.com>, linux-mips@linux-mips.org
Subject: Re: [PATCH 3/4] MIPS: malta-time: Don't use PIT timer for cevt/csrc
Date: Thu, 28 Apr 2016 17:36:43 +0100	[thread overview]
Message-ID: <20160428163643.GD2467@jhogan-linux.le.imgtec.org> (raw)
Message-ID: <20160428163643.YcosGHQmgvyU11FIsFkuuREB5BOneQ0-U29EXl9Rbnw@z> (raw)
In-Reply-To: <20160422192906.GO24051@linux-mips.org>

[-- Attachment #1: Type: text/plain, Size: 1144 bytes --]

On Fri, Apr 22, 2016 at 09:29:07PM +0200, Ralf Baechle wrote:
> On Fri, Apr 22, 2016 at 08:23:12PM +0100, James Hogan wrote:
> 
> > >  Not everyone uses virtualisation, so it's a functional regression for 
> > > them.  Can't you lower the priority for the timer instead so that it is 
> > > not selected by default, just as it's done with other platforms providing 
> > > a choice of timers?
> > 
> > I'll look into that. Looking back at my IRC logs I suspect I meant to
> > check why the PIT was taking priority before submitting upstream, but
> > forgot.
> 
> The PIT already has a very low rating and should only be used if everything
> else fails.  Clock scaling for example would make the cycle counter
> unusable, there might be no GIC available etc.  Otoh with SMP the PIT is
> only usable as a clock source but not clock event device.

I can't even reproduce the problem any longer. Even with the PIT drivers
loaded and a message in the log about PIT clocksource it doesn't seem to
be used, so we can just drop this one anyway. I've marked this patch as
rejected in patchwork. Sorry for the noise.

Thanks
James

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]

  reply	other threads:[~2016-04-28 16:36 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-04-22 17:19 [PATCH 0/4] MIPS: Guest timekeeping improvements James Hogan
2016-04-22 17:19 ` James Hogan
2016-04-22 17:19 ` [PATCH 1/4] MIPS: malta-time: Start GIC count before syncing to RTC James Hogan
2016-04-22 17:19   ` James Hogan
2016-04-22 17:19 ` [PATCH 2/4] MIPS: malta-time: Take seconds into account James Hogan
2016-04-22 17:19   ` James Hogan
2016-04-22 17:19 ` [PATCH 3/4] MIPS: malta-time: Don't use PIT timer for cevt/csrc James Hogan
2016-04-22 17:19   ` James Hogan
2016-04-22 18:57   ` Maciej W. Rozycki
2016-04-22 18:57     ` Maciej W. Rozycki
2016-04-22 19:23     ` James Hogan
2016-04-22 19:23       ` James Hogan
2016-04-22 19:29       ` Ralf Baechle
2016-04-28 16:36         ` James Hogan [this message]
2016-04-28 16:36           ` James Hogan
2016-04-22 17:19 ` [PATCH 4/4] MIPS: cevt-r4k: Dynamically calculate min_delta_ns James Hogan
2016-04-22 17:19   ` James Hogan

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=20160428163643.GD2467@jhogan-linux.le.imgtec.org \
    --to=james.hogan@imgtec.com \
    --cc=linux-mips@linux-mips.org \
    --cc=macro@imgtec.com \
    --cc=ralf@linux-mips.org \
    /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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox