From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932649Ab3BSMOd (ORCPT ); Tue, 19 Feb 2013 07:14:33 -0500 Received: from comal.ext.ti.com ([198.47.26.152]:44553 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932530Ab3BSMOc (ORCPT ); Tue, 19 Feb 2013 07:14:32 -0500 Date: Tue, 19 Feb 2013 14:14:00 +0200 From: Felipe Balbi To: Santosh Shilimkar CC: Afzal Mohammed , , , , , , Russell King , Tony Lindgren , Marc Zyngier , Nicolas Pitre , Will Deacon , Linus Walleij , Rob Herring , Grant Likely , Rob Landley , Sekhar Nori , Syed Mohammed Khasim Subject: Re: [PATCH, RFC 2/8] ARM: twd: register clock event for 1 core SMP Message-ID: <20130219121400.GP23197@arwen.pp.htv.fi> Reply-To: References: <51235076.8040200@ti.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="4IFtMBbmeqbTM/ox" Content-Disposition: inline In-Reply-To: <51235076.8040200@ti.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --4IFtMBbmeqbTM/ox Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Feb 19, 2013 at 03:44:14PM +0530, Santosh Shilimkar wrote: > On Monday 18 February 2013 05:07 PM, Afzal Mohammed wrote: > >Register percpu local timer for scheduler tick in the case of one core > >SMP configuration. In other cases - secondary cpu's as well as boot > >cpu's having more than one core, this is being registered as per > >existing boot flow, with a difference that they happens after delay > >calibration. Registering the clock for tick in case of one core should > >be done before Kernel calibrates delay (this is required to boot, > >unless local timer is the only one registered for tick). Registering > >twd local timer at init_time (which platforms are doing now) helps > >achieve that with the proposed change. > > > >This helps in an almost booting Kernel (minimal) by only relying on > >ARM parts for an A9 one core SMP. > > > >Signed-off-by: Afzal Mohammed > >--- > As mentioned in cover-letter, I don't think we have good > reasoning to make TWD to work with UP configuration. Even > you fix the timer code, there are more cascaded dependencies > which is not worth the effort. if CONFIG_SMP_ON_UP is enabled, smp_twd.c can still be compiled, right ? --=20 balbi --4IFtMBbmeqbTM/ox Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJRI2yIAAoJEIaOsuA1yqRE1NAP/iHA7+rdIXK5Az3QtnfGtUGD ur37R32eIs++SF480l/QuOaUpj1FK+qkRYvbjbJ7h7Ud4RT+cOqPIIPzcqPr14iK V/oi1g3nTRKlt+m1vi93HWsBRazt6ZTVUpT223aoUWrja7Zb99k8BnGDeNSahzse AIMsTI0Tk7cSDeZj5LFZ418X2lkorGi2xOc3uUyo9hsce3IhkCEnNzHa5D8UpX1h Ltq5ADuV919H5Ix8uYVXyhhmqHHkigEJPS6pFQ2QFpxEolakUSp+9k0FnSpnS+DX g64S9f150FdlEe9SNayr7r0YRJK3CPM3bwKXFCHFEV/XICvgtxnr+06bYvs8aRtM QL2ZSutdYjrwUM1x9+Q9ioOGmSgYH9qqejeBVhqe36DM5fiwo4WkOuksi84a0SLt 7L05iXeKlWA3fRdNymc966fafzaUvRuyq3/6GMRnHhTJ4eHsq13oMK7e8249ucr4 M1NDneCKbSZc2TVp7H7fr7bwBh+pKXLha22V1S7avMKdTQXdgPP5vaN8Zvi/s2f6 Xi0zMAifHCx4bOz37tnbWf6bYYMp8GGUeCAoFKM4cxW3rFY4flUKbTAi4B9mfQW9 /DZZzJWV3IMaax6VwtEXmWrHRZbr4D/f2oKIh7wGddISt/wo5PX0o74uC9h2AT/S wF9PIl5EOq/2pau2tFa3 =kqVe -----END PGP SIGNATURE----- --4IFtMBbmeqbTM/ox--