From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id AF7E3CDB474 for ; Mon, 16 Oct 2023 19:19:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ZOuJuMrceFcjnzAOhapnCBZN27qY6PXgu7VAmK12E/w=; b=UrGcnPDyFI0Y/k PTsw120mdjQ6RUkCzMj/fZ5kRqjUVUEuEh28r9C8cIybP9HoLIxRIamwxqfWLLYzoNvUKX4rv32Sh jM9ewoEJkxW6cpqLuTxxeEDtTRsFhs7nJTYAlr047qQlpgW54pVTYuaSJXVikGhv6gg3QzHi3CKlX eU1zXaQ3pHqjLa/Tla/r+2gK3003Cb1rRWi/qVxl/+R/RDyHmE4UxUzrfeTVv0XQxJQ++Dtr/VwIp 9ey/ee6/mY2XiFi5biOiqySOl3NtqbFijC+uXv2XBhYO0LU6RSWUdiKzeLKis4nF+E5MJxjjBGMFV HZLHvmYwt0Y0IL0hzquQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qsT7k-00AP1l-2H; Mon, 16 Oct 2023 19:19:32 +0000 Received: from out-190.mta1.migadu.com ([95.215.58.190]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qsT7g-00AP0B-2w for linux-arm-kernel@lists.infradead.org; Mon, 16 Oct 2023 19:19:30 +0000 Date: Mon, 16 Oct 2023 19:19:20 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1697483966; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=n/1jgeesV2PWOgvI7O5pgivkBRow3Dp9FODxS9F7AXE=; b=hxwkhlZhm6Zzs+grHwuUoeY01oeXkHbaMcKHQmlG58slLjNRTuDJ1D/F81V3i5EgWFurO7 onGZvWPs4l/7JKv1EQ3P37R7iE4nT+Cd5Ssc8ZCyVmjkJu6zX9rkhz4zN7cr5rsW7qcfCY WCsZmebF8cG6DOAkdplfhW12nz93ALI= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Oliver Upton To: Andre Przywara Cc: Catalin Marinas , Will Deacon , Marc Zyngier , Mark Rutland , James Morse , Suzuki K Poulose , Zenghui Yu , Daniel Lezcano , Thomas Gleixner , Rob Herring , Ross Burton , Khuong Dinh , Yang Shi , D Scott Phillips , Ilkka Koskinen , Joe Korty , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu Subject: Re: [PATCH] clocksource/drivers/arm_arch_timer: limit XGene-1 workaround Message-ID: References: <20231016153127.116101-1-andre.przywara@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20231016153127.116101-1-andre.przywara@arm.com> X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231016_121929_357757_2A6CE237 X-CRM114-Status: GOOD ( 10.27 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Oct 16, 2023 at 04:31:27PM +0100, Andre Przywara wrote: > The AppliedMicro XGene-1 CPU has an erratum where the timer condition > would only consider TVAL, not CVAL. We currently apply a workaround when > seeing the PartNum field of MIDR_EL1 being 0x000, under the assumption > that this would match only the XGene-1 CPU model. > However even the Ampere eMAG (aka XGene-3) uses that same part number, and > only differs in the "Variant" and "Revision" fields: XGene-1's MIDR is > 0x500f0000, our eMAG reports 0x503f0002. Experiments show the latter > doesn't show the faulty behaviour. > > Increase the specificity of the check to only consider partnum 0x000 and > variant 0x00, to exclude the Ampere eMAG. > > Fixes: 012f18850452 ("clocksource/drivers/arm_arch_timer: Work around broken CVAL implementations") > Reported-by: Ross Burton > Signed-off-by: Andre Przywara Reviewed-by: Oliver Upton -- Thanks, Oliver _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel