From patchwork Fri Jun 19 14:31:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 1313132 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-rtc-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=default header.b=sTnmdRBD; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 49pPKT4TR5zB48G for ; Sat, 20 Jun 2020 02:25:01 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389086AbgFSQYu (ORCPT ); Fri, 19 Jun 2020 12:24:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:53312 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389898AbgFSO5v (ORCPT ); Fri, 19 Jun 2020 10:57:51 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A4F4521835; Fri, 19 Jun 2020 14:57:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592578671; bh=stJzp+0uDkiYIjALJsrQp9bsVu0wkK33koz/CtwL74o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sTnmdRBDmcEeIKlOu9GEN6wlvhqqqT8Yrpe+hQMKhbZG9wG1ohhx01SfZ0hjiJYFc 8Zo4qMQMvl/WLbz6D4Md71uB++36WNES+w4Zcd/gG1E9mxTCFHYkMHPU/4DlYvUu1f GXGocqQqgGiK34nZ3RwQZkzC2ZTptwXUcoPn9Fkk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Serge Semin , Alexey Malahov , Thomas Bogendoerfer , Paul Burton , Ralf Baechle , Alessandro Zummo , Alexandre Belloni , Arnd Bergmann , Rob Herring , linux-mips@vger.kernel.org, linux-rtc@vger.kernel.org, devicetree@vger.kernel.org, Daniel Lezcano , Sasha Levin Subject: [PATCH 4.19 111/267] clocksource: dw_apb_timer: Make CPU-affiliation being optional Date: Fri, 19 Jun 2020 16:31:36 +0200 Message-Id: <20200619141654.178893412@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200619141648.840376470@linuxfoundation.org> References: <20200619141648.840376470@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: linux-rtc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rtc@vger.kernel.org From: Serge Semin [ Upstream commit cee43dbf2ee3f430434e2b66994eff8a1aeda889 ] Currently the DW APB Timer driver binds each clockevent timers to a particular CPU. This isn't good for multiple reasons. First of all seeing the device is placed on APB bus (which makes it accessible from any CPU core), accessible over MMIO and having the DYNIRQ flag set we can be sure that manually binding the timer to any CPU just isn't correct. By doing so we just set an extra limitation on device usage. This also doesn't reflect the device actual capability, since by setting the IRQ affinity we can make it virtually local to any CPU. Secondly imagine if you had a real CPU-local timer with the same rating and the same CPU-affinity. In this case if DW APB timer was registered first, then due to the clockevent framework tick-timer selection procedure we'll end up with the real CPU-local timer being left unselected for clock-events tracking. But on most of the platforms (MIPS/ARM/etc) such timers are normally embedded into the CPU core and are accessible with much better performance then devices placed on APB. For instance in MIPS architectures there is r4k-timer, which is CPU-local, assigned with the same rating, and normally its clockevent device is registered after the platform-specific one. So in order to fix all of these issues let's make the DW APB Timer CPU affinity being optional and deactivated by passing a negative CPU id, which will effectively set the DW APB clockevent timer cpumask to 'cpu_possible_mask'. Signed-off-by: Serge Semin Cc: Alexey Malahov Cc: Thomas Bogendoerfer Cc: Paul Burton Cc: Ralf Baechle Cc: Alessandro Zummo Cc: Alexandre Belloni Cc: Arnd Bergmann Cc: Rob Herring Cc: linux-mips@vger.kernel.org Cc: linux-rtc@vger.kernel.org Cc: devicetree@vger.kernel.org Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20200521204818.25436-5-Sergey.Semin@baikalelectronics.ru Signed-off-by: Sasha Levin --- drivers/clocksource/dw_apb_timer.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/clocksource/dw_apb_timer.c b/drivers/clocksource/dw_apb_timer.c index 1f5f734e4919..a018199575e3 100644 --- a/drivers/clocksource/dw_apb_timer.c +++ b/drivers/clocksource/dw_apb_timer.c @@ -225,7 +225,8 @@ static int apbt_next_event(unsigned long delta, /** * dw_apb_clockevent_init() - use an APB timer as a clock_event_device * - * @cpu: The CPU the events will be targeted at. + * @cpu: The CPU the events will be targeted at or -1 if CPU affiliation + * isn't required. * @name: The name used for the timer and the IRQ for it. * @rating: The rating to give the timer. * @base: I/O base for the timer registers. @@ -260,7 +261,7 @@ dw_apb_clockevent_init(int cpu, const char *name, unsigned rating, dw_ced->ced.max_delta_ticks = 0x7fffffff; dw_ced->ced.min_delta_ns = clockevent_delta2ns(5000, &dw_ced->ced); dw_ced->ced.min_delta_ticks = 5000; - dw_ced->ced.cpumask = cpumask_of(cpu); + dw_ced->ced.cpumask = cpu < 0 ? cpu_possible_mask : cpumask_of(cpu); dw_ced->ced.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ; dw_ced->ced.set_state_shutdown = apbt_shutdown; From patchwork Fri Jun 19 14:31:37 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 1313133 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-rtc-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=default header.b=zzzE6BxA; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 49pPKV33wxzB48H for ; Sat, 20 Jun 2020 02:25:02 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2394704AbgFSQYt (ORCPT ); Fri, 19 Jun 2020 12:24:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:53362 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390305AbgFSO5x (ORCPT ); Fri, 19 Jun 2020 10:57:53 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id DD88D21919; Fri, 19 Jun 2020 14:57:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592578673; bh=ve5sv8gFv7HyvXD4yB6SaZpZw1HlQaywAYRES+51m3s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zzzE6BxAGGHD56qfiMtmFr4lvCw3dqeUSDYOD2mmhPVGpTHIhQKY/54WdcVJFn2cC G468WgLvJnW9T7O3dX5HqcRwzMg3c4dC0wd2Q8gcvwwEs2w1sisj0xsbFSosW3Lm0r 2ls1vMbKoPu0RMxRoxuji2/Vxpd7Vs1eMU5HAGbY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Serge Semin , Alexey Malahov , Thomas Bogendoerfer , Paul Burton , Ralf Baechle , Alessandro Zummo , Alexandre Belloni , Arnd Bergmann , Rob Herring , linux-mips@vger.kernel.org, linux-rtc@vger.kernel.org, devicetree@vger.kernel.org, Daniel Lezcano , Sasha Levin Subject: [PATCH 4.19 112/267] clocksource: dw_apb_timer_of: Fix missing clockevent timers Date: Fri, 19 Jun 2020 16:31:37 +0200 Message-Id: <20200619141654.221930691@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200619141648.840376470@linuxfoundation.org> References: <20200619141648.840376470@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: linux-rtc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rtc@vger.kernel.org From: Serge Semin [ Upstream commit 6d2e16a3181bafb77b535095c39ad1c8b9558c8c ] Commit 100214889973 ("clocksource: dw_apb_timer_of: use clocksource_of_init") replaced a publicly available driver initialization method with one called by the timer_probe() method available after CLKSRC_OF. In current implementation it traverses all the timers available in the system and calls their initialization methods if corresponding devices were either in dtb or in acpi. But if before the commit any number of available timers would be installed as clockevent and clocksource devices, after that there would be at most two. The rest are just ignored since default case branch doesn't do anything. I don't see a reason of such behaviour, neither the commit message explains it. Moreover this might be wrong if on some platforms these timers might be used for different purpose, as virtually CPU-local clockevent timers and as an independent broadcast timer. So in order to keep the compatibility with the platforms where the order of the timers detection has some meaning, lets add the secondly discovered timer to be of clocksource/sched_clock type, while the very first and the others would provide the clockevents service. Fixes: 100214889973 ("clocksource: dw_apb_timer_of: use clocksource_of_init") Signed-off-by: Serge Semin Cc: Alexey Malahov Cc: Thomas Bogendoerfer Cc: Paul Burton Cc: Ralf Baechle Cc: Alessandro Zummo Cc: Alexandre Belloni Cc: Arnd Bergmann Cc: Rob Herring Cc: linux-mips@vger.kernel.org Cc: linux-rtc@vger.kernel.org Cc: devicetree@vger.kernel.org Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20200521204818.25436-7-Sergey.Semin@baikalelectronics.ru Signed-off-by: Sasha Levin --- drivers/clocksource/dw_apb_timer_of.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/clocksource/dw_apb_timer_of.c b/drivers/clocksource/dw_apb_timer_of.c index 69866cd8f4bb..3e4d0e5733d3 100644 --- a/drivers/clocksource/dw_apb_timer_of.c +++ b/drivers/clocksource/dw_apb_timer_of.c @@ -146,10 +146,6 @@ static int num_called; static int __init dw_apb_timer_init(struct device_node *timer) { switch (num_called) { - case 0: - pr_debug("%s: found clockevent timer\n", __func__); - add_clockevent(timer); - break; case 1: pr_debug("%s: found clocksource timer\n", __func__); add_clocksource(timer); @@ -160,6 +156,8 @@ static int __init dw_apb_timer_init(struct device_node *timer) #endif break; default: + pr_debug("%s: found clockevent timer\n", __func__); + add_clockevent(timer); break; }