From patchwork Fri Aug 22 21:43:14 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nathan Lynch X-Patchwork-Id: 4767271 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 4DE8CC0338 for ; Fri, 22 Aug 2014 21:46:27 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 870902018A for ; Fri, 22 Aug 2014 21:46:26 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3F42A20158 for ; Fri, 22 Aug 2014 21:46:25 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1XKwcn-0003sP-An; Fri, 22 Aug 2014 21:43:57 +0000 Received: from relay1.mentorg.com ([192.94.38.131]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1XKwcd-0003mz-5z for linux-arm-kernel@lists.infradead.org; Fri, 22 Aug 2014 21:43:47 +0000 Received: from svr-orw-exc-10.mgc.mentorg.com ([147.34.98.58]) by relay1.mentorg.com with esmtp id 1XKwcD-0006p6-IE from Nathan_Lynch@mentor.com ; Fri, 22 Aug 2014 14:43:21 -0700 Received: from SVR-ORW-FEM-04.mgc.mentorg.com ([147.34.97.41]) by SVR-ORW-EXC-10.mgc.mentorg.com with Microsoft SMTPSVC(6.0.3790.4675); Fri, 22 Aug 2014 14:43:21 -0700 Received: from localhost (147.34.91.1) by SVR-ORW-FEM-04.mgc.mentorg.com (147.34.97.41) with Microsoft SMTP Server (TLS) id 14.2.247.3; Fri, 22 Aug 2014 14:43:20 -0700 From: Nathan Lynch To: Daniel Lezcano Subject: [PATCH 1/4] clocksource: arm_arch_timer: change clocksource name if CP15 unavailable Date: Fri, 22 Aug 2014 16:43:14 -0500 Message-ID: <1408743797-7648-2-git-send-email-nathan_lynch@mentor.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1408743797-7648-1-git-send-email-nathan_lynch@mentor.com> References: <1408743797-7648-1-git-send-email-nathan_lynch@mentor.com> MIME-Version: 1.0 X-OriginalArrivalTime: 22 Aug 2014 21:43:21.0409 (UTC) FILETIME=[17DE8B10:01CFBE52] X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140822_144347_252715_53AB6FB7 X-CRM114-Status: GOOD ( 12.25 ) X-Spam-Score: -0.0 (/) Cc: Will Deacon , Russell King , Stephen Boyd , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The arm and arm64 VDSOs need CP15 access to the architected counter. If this is unavailable (which is allowed by ARM v7), indicate this by changing the clocksource name to "arch_mem_counter" before registering the clocksource. Suggested by Stephen Boyd. Signed-off-by: Nathan Lynch Reviewed-by: Stephen Boyd --- drivers/clocksource/arm_arch_timer.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 5163ec13429d..c99afdf12e98 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -429,11 +429,19 @@ static void __init arch_counter_register(unsigned type) u64 start_count; /* Register the CP15 based counter if we have one */ - if (type & ARCH_CP15_TIMER) + if (type & ARCH_CP15_TIMER) { arch_timer_read_counter = arch_counter_get_cntvct; - else + } else { arch_timer_read_counter = arch_counter_get_cntvct_mem; + /* If the clocksource name is "arch_sys_counter" the + * VDSO will attempt to read the CP15-based counter. + * Ensure this does not happen when CP15-based + * counter is not available. + */ + clocksource_counter.name = "arch_mem_counter"; + } + start_count = arch_timer_read_counter(); clocksource_register_hz(&clocksource_counter, arch_timer_rate); cyclecounter.mult = clocksource_counter.mult;