From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757328AbbA1UYs (ORCPT ); Wed, 28 Jan 2015 15:24:48 -0500 Received: from mail-ie0-f174.google.com ([209.85.223.174]:42510 "EHLO mail-ie0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755605AbbA1UYp (ORCPT ); Wed, 28 Jan 2015 15:24:45 -0500 MIME-Version: 1.0 In-Reply-To: <54C8EE04.6060809@linaro.org> References: <1422422306-27473-1-git-send-email-behanw@converseincode.com> <54C8EE04.6060809@linaro.org> Date: Wed, 28 Jan 2015 16:17:15 +0000 Message-ID: Subject: Re: [PATCH] bcm: address clang inline asm incompatibility From: Ard Biesheuvel To: Alex Elder Cc: Behan Webster , bcm@fixthebug.org, Florian Fainelli , Russell King - ARM Linux , Matt Porter , bcm-kernel-feedback-list@broadcom.com, "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 28 January 2015 at 14:11, Alex Elder wrote: > On 01/28/2015 05:15 AM, Ard Biesheuvel wrote: >> On 28 January 2015 at 05:18, Behan Webster wrote: >>> From: Alex Elder >>> >>> My GCC-based build environment likes to call register r12 by the >>> name "ip" in inline asm. Behan Webster informed me that his Clang- >>> based build environment likes "r12" instead. >>> >>> Try to make them both happy. >>> >>> Signed-off-by: Alex Elder >>> Signed-off-by: Behan Webster >>> --- >>> arch/arm/mach-bcm/bcm_kona_smc.c | 9 +++++++-- >>> 1 file changed, 7 insertions(+), 2 deletions(-) >>> >>> diff --git a/arch/arm/mach-bcm/bcm_kona_smc.c b/arch/arm/mach-bcm/bcm_kona_smc.c >>> index a55a7ec..3937bd5 100644 >>> --- a/arch/arm/mach-bcm/bcm_kona_smc.c >>> +++ b/arch/arm/mach-bcm/bcm_kona_smc.c >>> @@ -106,9 +106,14 @@ int __init bcm_kona_smc_init(void) >>> * request result appropriately. This result value is found in r0 >>> * when the "smc" request completes. >>> */ >>> +#ifdef __clang__ >>> +#define R12 "r12" >>> +#else /* !__clang__ */ >>> +#define R12 "ip" /* gcc calls r12 "ip" */ >>> +#endif /* !__clang__ */ >> >> Why not just use r12 for both? > > Yes, that would have been an obvious fix. But the > assembler (in the GCC environment) doesn't accept that. > Mine has no problems with it at all $ echo 'mov r12, #0' | arm-linux-gnueabihf-gcc -c -x assembler-with-cpp - and grepping for r12 under arch/arm suggests the same -- Ard. >>> static int bcm_kona_do_smc(u32 service_id, u32 buffer_phys) >>> { >>> - register u32 ip asm("ip"); /* Also called r12 */ >>> + register u32 ip asm(R12); /* Also called r12 */ >>> register u32 r0 asm("r0"); >>> register u32 r4 asm("r4"); >>> register u32 r5 asm("r5"); >>> @@ -120,7 +125,7 @@ static int bcm_kona_do_smc(u32 service_id, u32 buffer_phys) >>> >>> asm volatile ( >>> /* Make sure we got the registers we want */ >>> - __asmeq("%0", "ip") >>> + __asmeq("%0", R12) >>> __asmeq("%1", "r0") >>> __asmeq("%2", "r4") >>> __asmeq("%3", "r5") >>> -- >>> 1.9.1 >>> >>> >>> _______________________________________________ >>> linux-arm-kernel mailing list >>> linux-arm-kernel@lists.infradead.org >>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > From mboxrd@z Thu Jan 1 00:00:00 1970 From: ard.biesheuvel@linaro.org (Ard Biesheuvel) Date: Wed, 28 Jan 2015 16:17:15 +0000 Subject: [PATCH] bcm: address clang inline asm incompatibility In-Reply-To: <54C8EE04.6060809@linaro.org> References: <1422422306-27473-1-git-send-email-behanw@converseincode.com> <54C8EE04.6060809@linaro.org> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 28 January 2015 at 14:11, Alex Elder wrote: > On 01/28/2015 05:15 AM, Ard Biesheuvel wrote: >> On 28 January 2015 at 05:18, Behan Webster wrote: >>> From: Alex Elder >>> >>> My GCC-based build environment likes to call register r12 by the >>> name "ip" in inline asm. Behan Webster informed me that his Clang- >>> based build environment likes "r12" instead. >>> >>> Try to make them both happy. >>> >>> Signed-off-by: Alex Elder >>> Signed-off-by: Behan Webster >>> --- >>> arch/arm/mach-bcm/bcm_kona_smc.c | 9 +++++++-- >>> 1 file changed, 7 insertions(+), 2 deletions(-) >>> >>> diff --git a/arch/arm/mach-bcm/bcm_kona_smc.c b/arch/arm/mach-bcm/bcm_kona_smc.c >>> index a55a7ec..3937bd5 100644 >>> --- a/arch/arm/mach-bcm/bcm_kona_smc.c >>> +++ b/arch/arm/mach-bcm/bcm_kona_smc.c >>> @@ -106,9 +106,14 @@ int __init bcm_kona_smc_init(void) >>> * request result appropriately. This result value is found in r0 >>> * when the "smc" request completes. >>> */ >>> +#ifdef __clang__ >>> +#define R12 "r12" >>> +#else /* !__clang__ */ >>> +#define R12 "ip" /* gcc calls r12 "ip" */ >>> +#endif /* !__clang__ */ >> >> Why not just use r12 for both? > > Yes, that would have been an obvious fix. But the > assembler (in the GCC environment) doesn't accept that. > Mine has no problems with it at all $ echo 'mov r12, #0' | arm-linux-gnueabihf-gcc -c -x assembler-with-cpp - and grepping for r12 under arch/arm suggests the same -- Ard. >>> static int bcm_kona_do_smc(u32 service_id, u32 buffer_phys) >>> { >>> - register u32 ip asm("ip"); /* Also called r12 */ >>> + register u32 ip asm(R12); /* Also called r12 */ >>> register u32 r0 asm("r0"); >>> register u32 r4 asm("r4"); >>> register u32 r5 asm("r5"); >>> @@ -120,7 +125,7 @@ static int bcm_kona_do_smc(u32 service_id, u32 buffer_phys) >>> >>> asm volatile ( >>> /* Make sure we got the registers we want */ >>> - __asmeq("%0", "ip") >>> + __asmeq("%0", R12) >>> __asmeq("%1", "r0") >>> __asmeq("%2", "r4") >>> __asmeq("%3", "r5") >>> -- >>> 1.9.1 >>> >>> >>> _______________________________________________ >>> linux-arm-kernel mailing list >>> linux-arm-kernel at lists.infradead.org >>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >