From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org ([203.11.71.1]:50853 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753810AbeFDOL0 (ORCPT ); Mon, 4 Jun 2018 10:11:26 -0400 In-Reply-To: <20180530121922.22122-2-npiggin@gmail.com> From: Michael Ellerman Subject: Re: [v5, 1/4] powerpc/kbuild: set default generic machine type for 32-bit compile Message-Id: <40zxgc4r2sz9s4b@ozlabs.org> Date: Tue, 5 Jun 2018 00:11:23 +1000 (AEST) Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: Nicholas Piggin , linux-kbuild@vger.kernel.org Cc: Masahiro Yamada , linuxppc-dev@lists.ozlabs.org On Wed, 2018-05-30 at 12:19:19 UTC, Nicholas Piggin wrote: > Some 64-bit toolchains uses the wrong ISA variant for compiling 32-bit > kernels, even with -m32. Debian's powerpc64le is one such case, and > that is because it is built with --with-cpu=power8. > > So when cross compiling a 32-bit kernel with a 64-bit toolchain, set > -mcpu=powerpc initially, which is the generic 32-bit powerpc machine > type and scheduling model. CPU and platform code can override this > with subsequent -mcpu flags if necessary. > > This is not done for 32-bit toolchains otherwise it would override > their defaults, which are presumably set appropriately for the > environment (moreso than a 64-bit cross compiler). > > This fixes a lot of build failures due to incompatible assembly when > compiling 32-bit kernel with th Debian powerpc64le 64-bit toolchain. > > Cc: Segher Boessenkool > Signed-off-by: Nicholas Piggin Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/4bf4f42a2febb449a5cc5d79e7c58e cheers From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (bilbo.ozlabs.org [203.11.71.1]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 40zxgd1BXrzF12j for ; Tue, 5 Jun 2018 00:11:25 +1000 (AEST) In-Reply-To: <20180530121922.22122-2-npiggin@gmail.com> To: Nicholas Piggin , linux-kbuild@vger.kernel.org From: Michael Ellerman Cc: Masahiro Yamada , linuxppc-dev@lists.ozlabs.org, Nicholas Piggin Subject: Re: [v5, 1/4] powerpc/kbuild: set default generic machine type for 32-bit compile Message-Id: <40zxgc4r2sz9s4b@ozlabs.org> Date: Tue, 5 Jun 2018 00:11:23 +1000 (AEST) List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, 2018-05-30 at 12:19:19 UTC, Nicholas Piggin wrote: > Some 64-bit toolchains uses the wrong ISA variant for compiling 32-bit > kernels, even with -m32. Debian's powerpc64le is one such case, and > that is because it is built with --with-cpu=power8. > > So when cross compiling a 32-bit kernel with a 64-bit toolchain, set > -mcpu=powerpc initially, which is the generic 32-bit powerpc machine > type and scheduling model. CPU and platform code can override this > with subsequent -mcpu flags if necessary. > > This is not done for 32-bit toolchains otherwise it would override > their defaults, which are presumably set appropriately for the > environment (moreso than a 64-bit cross compiler). > > This fixes a lot of build failures due to incompatible assembly when > compiling 32-bit kernel with th Debian powerpc64le 64-bit toolchain. > > Cc: Segher Boessenkool > Signed-off-by: Nicholas Piggin Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/4bf4f42a2febb449a5cc5d79e7c58e cheers