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 X-Spam-Level: X-Spam-Status: No, score=-7.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 96415C4743C for ; Mon, 21 Jun 2021 10:24:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 79B7761059 for ; Mon, 21 Jun 2021 10:24:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230102AbhFUK1F (ORCPT ); Mon, 21 Jun 2021 06:27:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59352 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229661AbhFUK1C (ORCPT ); Mon, 21 Jun 2021 06:27:02 -0400 Received: from mail-wm1-x32f.google.com (mail-wm1-x32f.google.com [IPv6:2a00:1450:4864:20::32f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8572BC061574 for ; Mon, 21 Jun 2021 03:24:47 -0700 (PDT) Received: by mail-wm1-x32f.google.com with SMTP id l7-20020a05600c1d07b02901b0e2ebd6deso10323708wms.1 for ; Mon, 21 Jun 2021 03:24:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=CDiXxvYtfyxE5nFB19grFf8yJhbwkKeNX1uoZe/8Uvc=; b=iYhp2WQffqmJU3YQ3FdHYngsgmsFop0nY+fE0oobBV8Y+pTXI4LS43Evyzld6i9Qj9 dbQmB2+1HVtUSvGgSHdDxkPfiCQLhgYb5SVmzuImES+rZEmyeg/kEHInqko67OkZK1kR 8lDW7EmzIVdsEASl0OA3pMhBMaomQE1vs0h8M+r5pruTxOdq/eh9zrzYOYDObTvf+isg QM+Ssn7aK6vSs+ot5Eo4iNWPX5rqO5S5y2rIN301g9WkMbm8cfr9QXSRJSIg2ocBKI/K aXn7aiSkDvXCfLea8TfsU204ORV6dr2Cif+f4Al5ZYT+24XrcGB9vadALSUDw3p850hp 1b5g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=CDiXxvYtfyxE5nFB19grFf8yJhbwkKeNX1uoZe/8Uvc=; b=Yp9IrqTdUWd6t7ITm1IQfwGXusbmgmTLyQA3kx32IqeJdi/qcEl2aGGaGYyFEqgHY+ nqfaUVpUKEPRST8O3G8EtzSmbWGcvohbNd95bEST6MY/C8V8HQB/04WJ/3L2HovU9msn LAyM2QtjfsXMP6g6QZkzRvHZyFL872o8i/hEWaj9qpHfNL5MLUlH09I6pgcJMJbFyGpe /hCeMwjxrX4dynV/RFlIaxRpGqKz5Z9zsgg5dcmqo43C8Zgo+LH72IbcI5QXXJaJ5Qc2 hCL10DF9bH+UhtgAX/oKsXLNMrkLpEHN1CzLUcfMD55LS475J8lEA9YaEu+0aF7eLDyK F0Gg== X-Gm-Message-State: AOAM533+nfjakuOPhaLQwOjQBznbS3R6QhNWN7xfgml/PmhUJd4S7DMl 1LPCDhVRUwDh2HpBPS7cncPoKQ== X-Google-Smtp-Source: ABdhPJyZQ3CPhDv7pPIktHohGygVyJpoofZEJT9P7K2Hx2D0J427cfLpLmA6fyca61BcLiClNbY5Zg== X-Received: by 2002:a7b:c44d:: with SMTP id l13mr8003996wmi.69.1624271085972; Mon, 21 Jun 2021 03:24:45 -0700 (PDT) Received: from ?IPv6:2a01:e34:ed2f:f020:5ebd:8bd9:d549:4211? ([2a01:e34:ed2f:f020:5ebd:8bd9:d549:4211]) by smtp.googlemail.com with ESMTPSA id u18sm15538371wmj.15.2021.06.21.03.24.44 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 21 Jun 2021 03:24:45 -0700 (PDT) Subject: Re: [PATCH 1/2] clocksource/drivers/exynos_mct: Prioritise Arm arch timer on arm64 To: Marek Szyprowski , Will Deacon , Chanwoo Choi Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Krzysztof Kozlowski , Krzysztof Kozlowski , Thomas Gleixner References: <20210608154341.10794-1-will@kernel.org> <20210608154341.10794-2-will@kernel.org> <466bfc19-2260-87c6-c458-b43cf23617e3@samsung.com> <2a0181ea-a26e-65e9-16f6-cc233b6b296f@linaro.org> <20210617214748.GC25403@willie-the-truck> <95fb8ea3-f409-55ee-6b5c-f19858dd0fab@samsung.com> From: Daniel Lezcano Message-ID: <6847bb2f-02ac-35a4-bb7a-491a52325a60@linaro.org> Date: Mon, 21 Jun 2021 12:24:44 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: <95fb8ea3-f409-55ee-6b5c-f19858dd0fab@samsung.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 21/06/2021 12:17, Marek Szyprowski wrote: [ ... ] >>>>>> I'm not sure that exynos mct is working without problem >>>>>> such as the case of 6282edb72bed. >>>>>> As described on On ,6282edb72bed the arch timer on exynos SoC >>>>>> depends on Exynos MCT device. the arch timer is not able to work >>>>>> without Exynos MCT because of using the common module. >>>>> Is it possible to change the DT to have a phandle to the exynos_mct, so >>>>> it will be probed before the arch_arm_timer ? >>>> I think that DT changes is not proper way to keep the order between >>>> exynos_mct and arch timer. >>> exynos4_mct_frc_start() is called unconditionally from probe via >>> exynos4_clocksource_init() so as long as the mct probes first, then the >>> arch timer should work, no? The rating shouldn't affect that. >> How do you ensure the exynos mct is probed before the arch timer ? >> >> The Makefile provides the right order, but the dependency is implicit. > > In my test systems based on Exynos5433, the bootloader enabled MCT, so > kernel can also start with arch_timer then switch to MCT. The probe > order also depend on the order of DT nodes, so with the current dts MCT > is probed first. This is not the best approach, but so far it works. Right, generally assuming the firmware is doing the right thing from an initialization POV is not a good idea :/ But in our case, as pointed by Will, the cpuhotplug ordering gives the right sequence. So it should be fine. -- Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog 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 X-Spam-Level: X-Spam-Status: No, score=-5.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E2FFCC4743C for ; Mon, 21 Jun 2021 10:26:33 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 862D4611BD for ; Mon, 21 Jun 2021 10:26:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 862D4611BD Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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:Date: Message-ID:From:References:Cc:To:Subject:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=9WuZPk6+SNOEGeNXL8qpeTJQN1FUkDUh/IwtLpPQfEw=; b=Y9ePrt1Bz91w8q8+h1GTScdTWb o2kUChev++ROvbfeWE4jOATQuCxclEa5F28Y5oBeQt42bhywUbhyRfyKqmTLwiHskEbw01XFUWwo9 cCbTTUC8GiKLDgxwbFwdVGkrb8Z8gFRz339qddX9C7XsUSjBgHPoVzowdXgdINW3E73YKxKHjcOfl j0J0e77SvjJsGtPikVAAmsNWV5+fhBTHG9lKQH3ImFLgfb4ZMQ63xkGrxT2b0B4D95onHVkUz+jgM MdcUqONrSfXIYlgTqVlzA/N8YF8opwNaT/mOfCco0CABnjyW68jlXI1BprClgrnKszEFWs+JzOjPo zUhx5ZNA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1lvH6s-0035Zc-1p; Mon, 21 Jun 2021 10:24:54 +0000 Received: from mail-wm1-x32f.google.com ([2a00:1450:4864:20::32f]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1lvH6n-0035Xj-I3 for linux-arm-kernel@lists.infradead.org; Mon, 21 Jun 2021 10:24:51 +0000 Received: by mail-wm1-x32f.google.com with SMTP id l18-20020a1ced120000b029014c1adff1edso13460868wmh.4 for ; Mon, 21 Jun 2021 03:24:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=CDiXxvYtfyxE5nFB19grFf8yJhbwkKeNX1uoZe/8Uvc=; b=iYhp2WQffqmJU3YQ3FdHYngsgmsFop0nY+fE0oobBV8Y+pTXI4LS43Evyzld6i9Qj9 dbQmB2+1HVtUSvGgSHdDxkPfiCQLhgYb5SVmzuImES+rZEmyeg/kEHInqko67OkZK1kR 8lDW7EmzIVdsEASl0OA3pMhBMaomQE1vs0h8M+r5pruTxOdq/eh9zrzYOYDObTvf+isg QM+Ssn7aK6vSs+ot5Eo4iNWPX5rqO5S5y2rIN301g9WkMbm8cfr9QXSRJSIg2ocBKI/K aXn7aiSkDvXCfLea8TfsU204ORV6dr2Cif+f4Al5ZYT+24XrcGB9vadALSUDw3p850hp 1b5g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=CDiXxvYtfyxE5nFB19grFf8yJhbwkKeNX1uoZe/8Uvc=; b=qQecV07s4rBIlH783DQasOHjFmtrRbAWpB1v4YAN0hw/4GGBkkMCrX88oVXoWW80U3 Zp9HGP3TSfGo+h9gdUFBa1fVC3w/IsjFRDIL9VeITyXpFQtGrHb8tci4OFotZLwJRNwS +jgSTxGA+fjratXAe+3wg+0+9H5Fz+aSeREGaJ2HLH1gBzL4QCmRP6xfxNNqdvnrJ/K8 o0hhlGcesEiNZVb4ytNHP7A+MA5k7TSLmsMyi9jl/vPMdevzDNrEXDxNHaEBf4tOkO3W i9P4WiBhHOtEqB9aoMI5Wnx8dIm3NIpW82vWkIsy0pzwrv60AqyK0w8qS69GpTEATobH koTA== X-Gm-Message-State: AOAM532/nLqlf3b8C38SvMcrOkNa1MRh/rcGhMEHQXi8f1vS5OuhgMVa czIWMNffjLn88gCI7WxspC6z8A== X-Google-Smtp-Source: ABdhPJyZQ3CPhDv7pPIktHohGygVyJpoofZEJT9P7K2Hx2D0J427cfLpLmA6fyca61BcLiClNbY5Zg== X-Received: by 2002:a7b:c44d:: with SMTP id l13mr8003996wmi.69.1624271085972; Mon, 21 Jun 2021 03:24:45 -0700 (PDT) Received: from ?IPv6:2a01:e34:ed2f:f020:5ebd:8bd9:d549:4211? ([2a01:e34:ed2f:f020:5ebd:8bd9:d549:4211]) by smtp.googlemail.com with ESMTPSA id u18sm15538371wmj.15.2021.06.21.03.24.44 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 21 Jun 2021 03:24:45 -0700 (PDT) Subject: Re: [PATCH 1/2] clocksource/drivers/exynos_mct: Prioritise Arm arch timer on arm64 To: Marek Szyprowski , Will Deacon , Chanwoo Choi Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Krzysztof Kozlowski , Krzysztof Kozlowski , Thomas Gleixner References: <20210608154341.10794-1-will@kernel.org> <20210608154341.10794-2-will@kernel.org> <466bfc19-2260-87c6-c458-b43cf23617e3@samsung.com> <2a0181ea-a26e-65e9-16f6-cc233b6b296f@linaro.org> <20210617214748.GC25403@willie-the-truck> <95fb8ea3-f409-55ee-6b5c-f19858dd0fab@samsung.com> From: Daniel Lezcano Message-ID: <6847bb2f-02ac-35a4-bb7a-491a52325a60@linaro.org> Date: Mon, 21 Jun 2021 12:24:44 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: <95fb8ea3-f409-55ee-6b5c-f19858dd0fab@samsung.com> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210621_032449_673930_834A612A X-CRM114-Status: GOOD ( 19.05 ) 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="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org T24gMjEvMDYvMjAyMSAxMjoxNywgTWFyZWsgU3p5cHJvd3NraSB3cm90ZToKClsgLi4uIF0KCj4+ Pj4+PiBJJ20gbm90IHN1cmUgdGhhdCBleHlub3MgbWN0IGlzIHdvcmtpbmcgd2l0aG91dCBwcm9i bGVtCj4+Pj4+PiBzdWNoIGFzIHRoZSBjYXNlIG9mIDYyODJlZGI3MmJlZC4KPj4+Pj4+IEFzIGRl c2NyaWJlZCBvbiBPbiAsNjI4MmVkYjcyYmVkIHRoZSBhcmNoIHRpbWVyIG9uIGV4eW5vcyBTb0MK Pj4+Pj4+IGRlcGVuZHMgb24gRXh5bm9zIE1DVCBkZXZpY2UuIHRoZSBhcmNoIHRpbWVyIGlzIG5v dCBhYmxlIHRvIHdvcmsKPj4+Pj4+IHdpdGhvdXQgRXh5bm9zIE1DVCBiZWNhdXNlIG9mIHVzaW5n IHRoZSBjb21tb24gbW9kdWxlLgo+Pj4+PiBJcyBpdCBwb3NzaWJsZSB0byBjaGFuZ2UgdGhlIERU IHRvIGhhdmUgYSBwaGFuZGxlIHRvIHRoZSBleHlub3NfbWN0LCBzbwo+Pj4+PiBpdCB3aWxsIGJl IHByb2JlZCBiZWZvcmUgdGhlIGFyY2hfYXJtX3RpbWVyID8KPj4+PiBJIHRoaW5rIHRoYXQgRFQg Y2hhbmdlcyBpcyBub3QgcHJvcGVyIHdheSB0byBrZWVwIHRoZSBvcmRlciBiZXR3ZWVuCj4+Pj4g ZXh5bm9zX21jdCBhbmQgYXJjaCB0aW1lci4KPj4+IGV4eW5vczRfbWN0X2ZyY19zdGFydCgpIGlz IGNhbGxlZCB1bmNvbmRpdGlvbmFsbHkgZnJvbSBwcm9iZSB2aWEKPj4+IGV4eW5vczRfY2xvY2tz b3VyY2VfaW5pdCgpIHNvIGFzIGxvbmcgYXMgdGhlIG1jdCBwcm9iZXMgZmlyc3QsIHRoZW4gdGhl Cj4+PiBhcmNoIHRpbWVyIHNob3VsZCB3b3JrLCBubz8gVGhlIHJhdGluZyBzaG91bGRuJ3QgYWZm ZWN0IHRoYXQuCj4+IEhvdyBkbyB5b3UgZW5zdXJlIHRoZSBleHlub3MgbWN0IGlzIHByb2JlZCBi ZWZvcmUgdGhlIGFyY2ggdGltZXIgPwo+Pgo+PiBUaGUgTWFrZWZpbGUgcHJvdmlkZXMgdGhlIHJp Z2h0IG9yZGVyLCBidXQgdGhlIGRlcGVuZGVuY3kgaXMgaW1wbGljaXQuCj4gCj4gSW4gbXkgdGVz dCBzeXN0ZW1zIGJhc2VkIG9uIEV4eW5vczU0MzMsIHRoZSBib290bG9hZGVyIGVuYWJsZWQgTUNU LCBzbyAKPiBrZXJuZWwgY2FuIGFsc28gc3RhcnQgd2l0aCBhcmNoX3RpbWVyIHRoZW4gc3dpdGNo IHRvIE1DVC4gVGhlIHByb2JlIAo+IG9yZGVyIGFsc28gZGVwZW5kIG9uIHRoZSBvcmRlciBvZiBE VCBub2Rlcywgc28gd2l0aCB0aGUgY3VycmVudCBkdHMgTUNUIAo+IGlzIHByb2JlZCBmaXJzdC4g VGhpcyBpcyBub3QgdGhlIGJlc3QgYXBwcm9hY2gsIGJ1dCBzbyBmYXIgaXQgd29ya3MuCgpSaWdo dCwgZ2VuZXJhbGx5IGFzc3VtaW5nIHRoZSBmaXJtd2FyZSBpcyBkb2luZyB0aGUgcmlnaHQgdGhp bmcgZnJvbSBhbgppbml0aWFsaXphdGlvbiBQT1YgaXMgbm90IGEgZ29vZCBpZGVhIDovCgpCdXQg aW4gb3VyIGNhc2UsIGFzIHBvaW50ZWQgYnkgV2lsbCwgdGhlIGNwdWhvdHBsdWcgb3JkZXJpbmcg Z2l2ZXMgdGhlCnJpZ2h0IHNlcXVlbmNlLiBTbyBpdCBzaG91bGQgYmUgZmluZS4KCgotLSAKPGh0 dHA6Ly93d3cubGluYXJvLm9yZy8+IExpbmFyby5vcmcg4pSCIE9wZW4gc291cmNlIHNvZnR3YXJl IGZvciBBUk0gU29DcwoKRm9sbG93IExpbmFybzogIDxodHRwOi8vd3d3LmZhY2Vib29rLmNvbS9w YWdlcy9MaW5hcm8+IEZhY2Vib29rIHwKPGh0dHA6Ly90d2l0dGVyLmNvbS8jIS9saW5hcm9vcmc+ IFR3aXR0ZXIgfAo8aHR0cDovL3d3dy5saW5hcm8ub3JnL2xpbmFyby1ibG9nLz4gQmxvZwoKX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KbGludXgtYXJtLWtl cm5lbCBtYWlsaW5nIGxpc3QKbGludXgtYXJtLWtlcm5lbEBsaXN0cy5pbmZyYWRlYWQub3JnCmh0 dHA6Ly9saXN0cy5pbmZyYWRlYWQub3JnL21haWxtYW4vbGlzdGluZm8vbGludXgtYXJtLWtlcm5l bAo=