From patchwork Wed Jun 8 12:30:29 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Will Deacon X-Patchwork-Id: 862412 Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by demeter2.kernel.org (8.14.4/8.14.4) with ESMTP id p58JGuNP020262 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Wed, 8 Jun 2011 19:17:17 GMT Received: from canuck.infradead.org ([2001:4978:20e::1]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1QUHuv-0003eC-F1; Wed, 08 Jun 2011 12:31:25 +0000 Received: from localhost ([127.0.0.1] helo=canuck.infradead.org) by canuck.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1QUHuv-0002qp-1V; Wed, 08 Jun 2011 12:31:25 +0000 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]) by canuck.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1QUHuW-0002l0-IT for linux-arm-kernel@lists.infradead.org; Wed, 08 Jun 2011 12:31:01 +0000 Received: from localhost.localdomain (e102144-lin.cambridge.arm.com [10.1.69.60]) by cam-admin0.cambridge.arm.com (8.12.6/8.12.6) with ESMTP id p58CTbFG005135; Wed, 8 Jun 2011 13:29:38 +0100 (BST) From: Will Deacon To: linux-arm-kernel@lists.infradead.org Subject: [Patch v2 07/11] ARM: vfp: add VFPv4 capability detection and populate elf_hwcap Date: Wed, 8 Jun 2011 13:30:29 +0100 Message-Id: <1307536233-30089-8-git-send-email-will.deacon@arm.com> X-Mailer: git-send-email 1.7.0.4 MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1307536233-30089-1-git-send-email-will.deacon@arm.com> References: <1307536233-30089-1-git-send-email-will.deacon@arm.com> X-Spam-Note: CRM114 invocation failed X-Spam-Score: -0.0 (/) X-Spam-Report: SpamAssassin version 3.3.1 on canuck.infradead.org summary: Content analysis details: (-0.0 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 T_RP_MATCHES_RCVD Envelope sender domain matches handover relay domain Cc: dave.martin@linaro.org, Will Deacon X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter2.kernel.org [140.211.167.43]); Wed, 08 Jun 2011 19:17:17 +0000 (UTC) The presence of VFPv4 cannot be detected simply by looking at the FPSID subarchitecture field, as a value >= 2 signifies the architecture as VFPv3 or later. This patch reads from MVFR1 to check whether or not the fused multiple accumulate instructions are supported. Since these are introduced with VFPv4, this tells us what we need to know. Signed-off-by: Will Deacon --- arch/arm/vfp/vfpmodule.c | 6 ++++-- 1 files changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c index f25e7ec..650d90b 100644 --- a/arch/arm/vfp/vfpmodule.c +++ b/arch/arm/vfp/vfpmodule.c @@ -582,7 +582,6 @@ static int __init vfp_init(void) elf_hwcap |= HWCAP_VFPv3D16; } #endif -#ifdef CONFIG_NEON /* * Check for the presence of the Advanced SIMD * load/store instructions, integer and single @@ -590,10 +589,13 @@ static int __init vfp_init(void) * for NEON if the hardware has the MVFR registers. */ if ((read_cpuid_id() & 0x000f0000) == 0x000f0000) { +#ifdef CONFIG_NEON if ((fmrx(MVFR1) & 0x000fff00) == 0x00011100) elf_hwcap |= HWCAP_NEON; - } #endif + if ((fmrx(MVFR1) & 0xf0000000) == 0x10000000) + elf_hwcap |= HWCAP_VFPv4; + } } return 0; }