From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752119AbbCSJUI (ORCPT ); Thu, 19 Mar 2015 05:20:08 -0400 Received: from down.free-electrons.com ([37.187.137.238]:57712 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751129AbbCSJUE (ORCPT ); Thu, 19 Mar 2015 05:20:04 -0400 Date: Thu, 19 Mar 2015 10:18:43 +0100 From: "maxime.ripard" To: "kevin.z.m.zh@gmail.com" Cc: "linux-sunxi@googlegroups.com" , Chen-Yu Tsai , linux-arm-kernel , linux-kernel , Marc Zyngier Subject: Re: [linux-sunxi] Re: [PATCH 2/3] ARM: sun8i: Add SMP support for the Allwinner A23 Message-ID: <20150319091843.GA4255@lukather> References: <1426649042-30547-1-git-send-email-wens@csie.org> <1426649042-30547-3-git-send-email-wens@csie.org> <20150318102939.GP4638@lukather> <2015031912050362587032@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="G4iJoqBmSsgzjUCe" Content-Disposition: inline In-Reply-To: <2015031912050362587032@gmail.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --G4iJoqBmSsgzjUCe Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Kevin, On Thu, Mar 19, 2015 at 12:05:06PM +0800, kevin.z.m.zh@gmail.com wrote: > >> One question I couldn't find any answer to is that does the SMP bit is > >> set in secondary_startup? > >> > >> I couldn't find where it was set, but it still looks like the right > >> thing to do, so I would expect the code to do that. > >=20 > > I don't see it either. The sun8i code is just the sun6i code with the > > power clamps removed. And sun6i secondary_startup was removed some time > > ago in commit 1146b600044d ("ARM: sunxi: fix build for THUMB2_KERNEL"). > >=20 > > ChenYu > > The SMP bit should be set in the function of "__v7_ca7mp_setup", which is= located > in the file: > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/arch= /arm/mm/proc-v7.S?id=3Drefs/tags/v4.0-rc4 > I'm not sure if this is your discussion. It is, but I wasn't seeing it called anywhere in the secondary_startup code path. I was expecting a direct call, but it looks like it's a dynamic call, with a function-pointer like call, that is indeed run both in the kernel entry point and the secondary_startup. https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/arch/a= rm/kernel/head.S?id=3Drefs/tags/v4.0-rc4#n389 Thanks! Maxime --=20 Maxime Ripard, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com --G4iJoqBmSsgzjUCe Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJVCpRzAAoJEBx+YmzsjxAgtWMP/j/PpWq9QJmjOb3f0XO1RKtW Eivk7niSOvaoX1Dk+8hqPTVzHWaC9nLbR/ZtyrcFSwCOYPd5k5QMnDgcPDv+QDp+ /9R6siELXFppufF52S/SUJQ+dntV3kYkEum039c6kQvc9zCVwdHQTXNSCRrkVKCZ govARdzGwj9hYmfzRVrtN2l9YL+018+HhWneOhpoZR3Lge02OHJB+/Hc8L4dKLiZ oy55D/yN1oycf74MnT4SeM+tHfE2uaqmLSQUQVd0OxhhchyKpYhN4D+/48VtX6YX gffZ/wb5McOcyM0wgiBaFNKRDqmL5q6CV7HFkba61IOM3i/gSyKSBk57qW/qa/dz 1q3upqd6W44+1zKh6dQ6VjV6Bmpir1hDMpJCKKerfmUjJEPjqGGCwAxpQKKSW5TN D0uHbre3a/BD7JikUgNQRiamIkoA3mE+yFIxziFl80t5Wy6MLd6SgqDs5QEWwBIr 9ZR8AMhxXALrj0NqzkNRCq3zGWRJMyC3kPW5qts7DJ1Gj+hEPlwADdIOpZYe6k5H VozCNRqTmGBw9QNMkc7GAXtsogJfLE2nxMfSgY0MPm6/6l7psv3EWvENtKqDPBV0 aRX868J/rTKYKL5/OorC0Ozah6UARUfuDZyiVIzljFhOjuEL0QqIxJYUEYpKipaG cXSCEu4n5zTK/IWqEa1a =tnzI -----END PGP SIGNATURE----- --G4iJoqBmSsgzjUCe--