From patchwork Fri Jun 17 08:19:36 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Will Deacon X-Patchwork-Id: 890742 Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by demeter1.kernel.org (8.14.4/8.14.4) with ESMTP id p5H8NOQ8029240 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Fri, 17 Jun 2011 08:23:44 GMT Received: from canuck.infradead.org ([2001:4978:20e::1]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1QXUKH-0003PA-Dm; Fri, 17 Jun 2011 08:22:49 +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 1QXUKH-0003Je-0m; Fri, 17 Jun 2011 08:22:49 +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 1QXUHY-0002gs-RV for linux-arm-kernel@lists.infradead.org; Fri, 17 Jun 2011 08:20:03 +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 p5H8HxFF010544; Fri, 17 Jun 2011 09:18:00 +0100 (BST) From: Will Deacon To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v3 06/10] ARM: vfp: add VFPv4 capability detection and populate elf_hwcap Date: Fri, 17 Jun 2011 09:19:36 +0100 Message-Id: <1308298780-28000-7-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: <1308298780-28000-1-git-send-email-will.deacon@arm.com> References: <1308298780-28000-1-git-send-email-will.deacon@arm.com> X-CRM114-Version: 20090807-BlameThorstenAndJenny ( TRE 0.7.6 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20110617_042001_350414_A7FE0742 X-CRM114-Status: GOOD ( 12.96 ) 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 (demeter1.kernel.org [140.211.167.41]); Fri, 17 Jun 2011 08:23:45 +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 multiply 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; }