From patchwork Thu Dec 13 18:00:41 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Russell King (Oracle)" X-Patchwork-Id: 10729433 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9A1DB13AF for ; Thu, 13 Dec 2018 18:01:05 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8C72B2C834 for ; Thu, 13 Dec 2018 18:01:05 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8AD842C7FE; Thu, 13 Dec 2018 18:01:05 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SORTED_RECIPS, SUSPICIOUS_RECIPS autolearn=no version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 35BF82C82D for ; Thu, 13 Dec 2018 18:01:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Date:Message-Id:MIME-Version:Subject:To :From:References:In-Reply-To:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=QO3Pcs9EMlJtFDybYoh3qs+NXG4gIiMqu3JAJK50bxA=; b=oOUXSU8GKPo1+Z BBrY29y84I5ywO1lVwT1Bx6Xwqd2uTYM6yOWSjwwJNMMSRDA3QTwsctiGZ6E6ZApog7ZSfft3jWZi v81EumvUOjMpPtfNg0iw8Cqea5WPi3rkHj1cI1TYZzM5KTrl4zjYRdgiD6cbRAil44vvomZPZhH1C Hy9jDaLFT07VNfUrPbfLfWsn2/+/wdlw5IovBD5AirkA4PHJovVDh7g9kOaeVx77CHZIpuXViBrGc xH9lDKmV8ajBiAEqV2rWiuf6utBZ26DDIkwMFQh/gyfp2JvEjdU6hIfnDDEZqjzgD5wgaa4zahMj/ t4FigtcG/tWkSjs1f/xw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVIF-00063z-88; Thu, 13 Dec 2018 18:01:03 +0000 Received: from pandora.armlinux.org.uk ([2001:4d48:ad52:3201:214:fdff:fe10:1be6]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVIC-00062C-Bj for linux-arm-kernel@lists.infradead.org; Thu, 13 Dec 2018 18:01:01 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2014; h=Date:Sender:Message-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References: In-Reply-To:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=GwHXPmrKplCV5SoH+8i/717kAdq8R+O584srpN6C4fE=; b=NoOgp/JrNEhICetl5br4BgfdBj WJK1VqxEhqI+lFxSBs1c3WbUuN5aIzOvPbkyTtmI7LivJrtyKdUrOlZi2AHsmw6vhLBzrSpltD4/X 6ezO8KS/tOvke2NBLN8gsk87d9zplB8HopbQQZrkiNaLuM756PnP+zIOOsK1F/kmjE0E=; Received: from e0022681537dd.dyn.armlinux.org.uk ([2001:4d48:ad52:3201:222:68ff:fe15:37dd]:59198 helo=rmk-PC.armlinux.org.uk) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.90_1) (envelope-from ) id 1gXVHu-0003rz-Cm; Thu, 13 Dec 2018 18:00:42 +0000 Received: from rmk by rmk-PC.armlinux.org.uk with local (Exim 4.82_1-5b7a7c0-XX) (envelope-from ) id 1gXVHt-00088Q-DP; Thu, 13 Dec 2018 18:00:41 +0000 In-Reply-To: <20181213175952.GC26090@n2100.armlinux.org.uk> References: <20181213175952.GC26090@n2100.armlinux.org.uk> From: Russell King To: linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-omap@vger.kernel.org, linux-oxnas@groups.io, linux-samsung-soc@vger.kernel.org, linux-soc@vger.kernel.org Subject: [PATCH 1/9] ARM: omap2: remove unnecessary boot_lock MIME-Version: 1.0 Content-Disposition: inline Message-Id: Date: Thu, 13 Dec 2018 18:00:41 +0000 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181213_100100_396181_1F6F5C27 X-CRM114-Status: GOOD ( 11.34 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Tony Lindgren Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The boot_lock is something that was required for ARM development platforms to ensure that the delay calibration worked properly. This is not necessary for modern platforms that have better bus bandwidth and do not need to calibrate the delay loop for secondary cores. Remove the boot_lock entirely. Acked-by: Tony Lindgren Signed-off-by: Russell King --- arch/arm/mach-omap2/omap-smp.c | 20 -------------------- 1 file changed, 20 deletions(-) diff --git a/arch/arm/mach-omap2/omap-smp.c b/arch/arm/mach-omap2/omap-smp.c index 1c73694c871a..10e070368f64 100644 --- a/arch/arm/mach-omap2/omap-smp.c +++ b/arch/arm/mach-omap2/omap-smp.c @@ -69,8 +69,6 @@ static const struct omap_smp_config omap5_cfg __initconst = { .startup_addr = omap5_secondary_startup, }; -static DEFINE_SPINLOCK(boot_lock); - void __iomem *omap4_get_scu_base(void) { return cfg.scu_base; @@ -173,12 +171,6 @@ static void omap4_secondary_init(unsigned int cpu) /* Enable ACR to allow for ICUALLU workaround */ omap5_secondary_harden_predictor(); } - - /* - * Synchronise with the boot thread. - */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); } static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle) @@ -188,12 +180,6 @@ static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle) static struct powerdomain *cpu1_pwrdm; /* - * Set synchronisation state between this boot processor - * and the secondary one - */ - spin_lock(&boot_lock); - - /* * Update the AuxCoreBoot0 with boot state for secondary core. * omap4_secondary_startup() routine will hold the secondary core till * the AuxCoreBoot1 register is updated with cpu state @@ -266,12 +252,6 @@ static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle) arch_send_wakeup_ipi_mask(cpumask_of(cpu)); - /* - * Now the secondary core is starting up let it run its - * calibrations, then wait for it to finish - */ - spin_unlock(&boot_lock); - return 0; } From patchwork Thu Dec 13 18:00:46 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Russell King (Oracle)" X-Patchwork-Id: 10729441 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D498913AF for ; Thu, 13 Dec 2018 18:01:22 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C51912C4D7 for ; Thu, 13 Dec 2018 18:01:22 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B85182C7E3; Thu, 13 Dec 2018 18:01:22 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 5DF9F2C4D7 for ; Thu, 13 Dec 2018 18:01:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Date:Message-Id:MIME-Version:Subject:To :From:References:In-Reply-To:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=HxsnnFMlYegj2TmTQ+4mmWMI+7fAUkRgWGgWMF8OtpM=; b=rSlDk1eEDhLzed AEGphovcFiCtUUB9Kp58kFR15h/9+LjLpaITxr4ey0k6p73bFSW69+CSR7LIAp8NPnNguLrFE63xa 9lgvzp3gO8jyMFsknl3j0ipsmI0ynSNHSLxBKVmQqwSgUAKwn6X5FIdj14ZyQm8dtcolcaiF0/f4B OBVmBUfUyjcNAmisynqT7pVcQz4QtVLXnE7eXtR2cLf4RFj1FwmAp5cwM4xbhEUY8VcEJ66injZH4 F4fdK+uyKN1Egva75pRfNoJ6wbWERE+RyWaNFx2ZRs8ZPPmMb8AvR+Kl79sEjjr4c+Im7vSzB/yHt 0mtnUdXwvd6Ds27oXSJg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVIV-0006Jm-SJ; Thu, 13 Dec 2018 18:01:19 +0000 Received: from pandora.armlinux.org.uk ([2001:4d48:ad52:3201:214:fdff:fe10:1be6]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVIC-00062x-Bi for linux-arm-kernel@lists.infradead.org; Thu, 13 Dec 2018 18:01:05 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2014; h=Date:Sender:Message-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References: In-Reply-To:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=CWcL/Rs9KXzJcRDbvRIDgM9ZNPsgv24LAzEZVp2+Om8=; b=C9neayi/mlHXQib/ebCniPaLN4 X4szvNS8AmEYeSiZE/xtCmpJJ4MfhumLVcf4q7u0GDDv61WVFtAoBPZn9qBvdoW42CtOUCw8KKu2L 0yWLJ2XukB5S/LeV5My3nnpngu9RJP4rQT/iLUReKnGCKmE6HEHlkH/cS/eaVOnHsA2E=; Received: from e0022681537dd.dyn.armlinux.org.uk ([fd8f:7570:feb6:1:222:68ff:fe15:37dd]:49256 helo=rmk-PC.armlinux.org.uk) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.90_1) (envelope-from ) id 1gXVI0-0003s8-IV; Thu, 13 Dec 2018 18:00:48 +0000 Received: from rmk by rmk-PC.armlinux.org.uk with local (Exim 4.82_1-5b7a7c0-XX) (envelope-from ) id 1gXVHy-00088e-JK; Thu, 13 Dec 2018 18:00:46 +0000 In-Reply-To: <20181213175952.GC26090@n2100.armlinux.org.uk> References: <20181213175952.GC26090@n2100.armlinux.org.uk> From: Russell King To: linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-omap@vger.kernel.org, linux-oxnas@groups.io, linux-samsung-soc@vger.kernel.org, linux-soc@vger.kernel.org Subject: [PATCH 2/9] ARM: qcom: remove unnecessary boot_lock MIME-Version: 1.0 Content-Disposition: inline Message-Id: Date: Thu, 13 Dec 2018 18:00:46 +0000 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181213_100100_395957_5ACF9047 X-CRM114-Status: GOOD ( 11.61 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Andy Gross , David Brown Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The boot_lock is something that was required for ARM development platforms to ensure that the delay calibration worked properly. This is not necessary for modern platforms that have better bus bandwidth and do not need to calibrate the delay loop for secondary cores. Remove the boot_lock entirely. Signed-off-by: Russell King Reviewed-by: Stephen Boyd --- arch/arm/mach-qcom/platsmp.c | 26 -------------------------- 1 file changed, 26 deletions(-) diff --git a/arch/arm/mach-qcom/platsmp.c b/arch/arm/mach-qcom/platsmp.c index 5494c9e0c909..99a6a5e809e0 100644 --- a/arch/arm/mach-qcom/platsmp.c +++ b/arch/arm/mach-qcom/platsmp.c @@ -46,8 +46,6 @@ extern void secondary_startup_arm(void); -static DEFINE_SPINLOCK(boot_lock); - #ifdef CONFIG_HOTPLUG_CPU static void qcom_cpu_die(unsigned int cpu) { @@ -55,15 +53,6 @@ static void qcom_cpu_die(unsigned int cpu) } #endif -static void qcom_secondary_init(unsigned int cpu) -{ - /* - * Synchronise with the boot thread. - */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); -} - static int scss_release_secondary(unsigned int cpu) { struct device_node *node; @@ -281,24 +270,12 @@ static int qcom_boot_secondary(unsigned int cpu, int (*func)(unsigned int)) } /* - * set synchronisation state between this boot processor - * and the secondary one - */ - spin_lock(&boot_lock); - - /* * Send the secondary CPU a soft interrupt, thereby causing * the boot monitor to read the system wide flags register, * and branch to the address found there. */ arch_send_wakeup_ipi_mask(cpumask_of(cpu)); - /* - * now the secondary core is starting up let it run its - * calibrations, then wait for it to finish - */ - spin_unlock(&boot_lock); - return ret; } @@ -334,7 +311,6 @@ static void __init qcom_smp_prepare_cpus(unsigned int max_cpus) static const struct smp_operations smp_msm8660_ops __initconst = { .smp_prepare_cpus = qcom_smp_prepare_cpus, - .smp_secondary_init = qcom_secondary_init, .smp_boot_secondary = msm8660_boot_secondary, #ifdef CONFIG_HOTPLUG_CPU .cpu_die = qcom_cpu_die, @@ -344,7 +320,6 @@ CPU_METHOD_OF_DECLARE(qcom_smp, "qcom,gcc-msm8660", &smp_msm8660_ops); static const struct smp_operations qcom_smp_kpssv1_ops __initconst = { .smp_prepare_cpus = qcom_smp_prepare_cpus, - .smp_secondary_init = qcom_secondary_init, .smp_boot_secondary = kpssv1_boot_secondary, #ifdef CONFIG_HOTPLUG_CPU .cpu_die = qcom_cpu_die, @@ -354,7 +329,6 @@ CPU_METHOD_OF_DECLARE(qcom_smp_kpssv1, "qcom,kpss-acc-v1", &qcom_smp_kpssv1_ops) static const struct smp_operations qcom_smp_kpssv2_ops __initconst = { .smp_prepare_cpus = qcom_smp_prepare_cpus, - .smp_secondary_init = qcom_secondary_init, .smp_boot_secondary = kpssv2_boot_secondary, #ifdef CONFIG_HOTPLUG_CPU .cpu_die = qcom_cpu_die, From patchwork Thu Dec 13 18:00:51 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Russell King (Oracle)" X-Patchwork-Id: 10729457 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 227D113BF for ; Thu, 13 Dec 2018 18:01:36 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0C6A42C4D7 for ; Thu, 13 Dec 2018 18:01:36 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id F32442C80B; Thu, 13 Dec 2018 18:01:35 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SORTED_RECIPS, SUSPICIOUS_RECIPS autolearn=no version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 194DE2C4D7 for ; Thu, 13 Dec 2018 18:01:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Date:Message-Id:MIME-Version:Subject:To :From:References:In-Reply-To:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=NwFYQypDBOso/cSqs6cSUn7BefRIW2lCbZbx1d1O7aQ=; b=YYfg+NievVwpXQ duWstux3W9PRcEj3m6TmzEHDrXO+pgYdNF/TLPhgnZS+lempe3BvN5R5U8JXhdMhimL64fJqpBYiw tpMANNZVi688r+FHVrM1HLtI2aLOEBz0tjKN7mzC/d36hLuWLrU6GreFx9nASbLEeB/ZzKDLEUag0 9IiM5t3rCqTS26YjEkZr0knGp0C1fkq/6dEW9OlQe9vwGdK7qkFbK9+Jy/xuomnhkSdy74eKyHni5 OBuBM3IILvhmtd8Gq2xQMEOf1JF7GMCCrEVZLwssq6sQYabmVbOl4EpemqODU2/NuWNA5I8+vwWGV KwZApu5h6BxaTuSI15WQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVIh-0006Xg-H5; Thu, 13 Dec 2018 18:01:31 +0000 Received: from pandora.armlinux.org.uk ([2001:4d48:ad52:3201:214:fdff:fe10:1be6]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVIO-00063I-GH for linux-arm-kernel@lists.infradead.org; Thu, 13 Dec 2018 18:01:14 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2014; h=Date:Sender:Message-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References: In-Reply-To:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=V8bov3LQxKS+0wgZ/p0gc863/fFXgsfqhoabofSGwog=; b=aA8LM/dTq3dtk+PwBBk94AzpNq tt5Y5420nZ/aICO6UyuaRKsck1QHJpTItEAYKgVE36DoWHJRmZmaa4O16SwdfmVWb3lefsfb6SxaK cbuxnC/QO7RyXbGJDjm+ZUOdxk4cAt4yu5xOWwwLjLOBThOAi2ETixlL7mNleAzj4fUU=; Received: from e0022681537dd.dyn.armlinux.org.uk ([2002:4e20:1eda:1:222:68ff:fe15:37dd]:58688 helo=rmk-PC.armlinux.org.uk) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.90_1) (envelope-from ) id 1gXVI5-0003sF-9Z; Thu, 13 Dec 2018 18:00:53 +0000 Received: from rmk by rmk-PC.armlinux.org.uk with local (Exim 4.82_1-5b7a7c0-XX) (envelope-from ) id 1gXVI3-00088u-N6; Thu, 13 Dec 2018 18:00:52 +0000 In-Reply-To: <20181213175952.GC26090@n2100.armlinux.org.uk> References: <20181213175952.GC26090@n2100.armlinux.org.uk> From: Russell King To: linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-omap@vger.kernel.org, linux-oxnas@groups.io, linux-samsung-soc@vger.kernel.org, linux-soc@vger.kernel.org Subject: [PATCH 3/9] ARM: oxnas: remove CPU hotplug implementation MIME-Version: 1.0 Content-Disposition: inline Message-Id: Date: Thu, 13 Dec 2018 18:00:51 +0000 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181213_100112_597803_57CBB835 X-CRM114-Status: GOOD ( 16.04 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Neil Armstrong Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The CPU hotplug implementation on this platform is cargo-culted from the plat-versatile implementation, and is buggy. Once a CPU hits the "low power" loop, it will wait for pen_release to be set to the CPU number to wake up again - but nothing in this implementation does that. So, once a CPU has entered cpu_die() it will never, ever leave. Remove this useless cargo-culted implementation. Signed-off-by: Russell King Acked-by: Neil Armstrong --- arch/arm/mach-oxnas/Makefile | 1 - arch/arm/mach-oxnas/hotplug.c | 109 ------------------------------------------ arch/arm/mach-oxnas/platsmp.c | 4 -- 3 files changed, 114 deletions(-) delete mode 100644 arch/arm/mach-oxnas/hotplug.c diff --git a/arch/arm/mach-oxnas/Makefile b/arch/arm/mach-oxnas/Makefile index b625906a9970..61a34e1c0f22 100644 --- a/arch/arm/mach-oxnas/Makefile +++ b/arch/arm/mach-oxnas/Makefile @@ -1,2 +1 @@ obj-$(CONFIG_SMP) += platsmp.o headsmp.o -obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o diff --git a/arch/arm/mach-oxnas/hotplug.c b/arch/arm/mach-oxnas/hotplug.c deleted file mode 100644 index 854f29b8cba6..000000000000 --- a/arch/arm/mach-oxnas/hotplug.c +++ /dev/null @@ -1,109 +0,0 @@ -/* - * Copyright (C) 2002 ARM Ltd. - * All Rights Reserved - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ -#include -#include -#include - -#include -#include - -static inline void cpu_enter_lowpower(void) -{ - unsigned int v; - - asm volatile( - " mcr p15, 0, %1, c7, c5, 0\n" - " mcr p15, 0, %1, c7, c10, 4\n" - /* - * Turn off coherency - */ - " mrc p15, 0, %0, c1, c0, 1\n" - " bic %0, %0, #0x20\n" - " mcr p15, 0, %0, c1, c0, 1\n" - " mrc p15, 0, %0, c1, c0, 0\n" - " bic %0, %0, %2\n" - " mcr p15, 0, %0, c1, c0, 0\n" - : "=&r" (v) - : "r" (0), "Ir" (CR_C) - : "cc"); -} - -static inline void cpu_leave_lowpower(void) -{ - unsigned int v; - - asm volatile( "mrc p15, 0, %0, c1, c0, 0\n" - " orr %0, %0, %1\n" - " mcr p15, 0, %0, c1, c0, 0\n" - " mrc p15, 0, %0, c1, c0, 1\n" - " orr %0, %0, #0x20\n" - " mcr p15, 0, %0, c1, c0, 1\n" - : "=&r" (v) - : "Ir" (CR_C) - : "cc"); -} - -static inline void platform_do_lowpower(unsigned int cpu, int *spurious) -{ - /* - * there is no power-control hardware on this platform, so all - * we can do is put the core into WFI; this is safe as the calling - * code will have already disabled interrupts - */ - for (;;) { - /* - * here's the WFI - */ - asm(".word 0xe320f003\n" - : - : - : "memory", "cc"); - - if (pen_release == cpu_logical_map(cpu)) { - /* - * OK, proper wakeup, we're done - */ - break; - } - - /* - * Getting here, means that we have come out of WFI without - * having been woken up - this shouldn't happen - * - * Just note it happening - when we're woken, we can report - * its occurrence. - */ - (*spurious)++; - } -} - -/* - * platform-specific code to shutdown a CPU - * - * Called with IRQs disabled - */ -void ox820_cpu_die(unsigned int cpu) -{ - int spurious = 0; - - /* - * we're ready for shutdown now, so do it - */ - cpu_enter_lowpower(); - platform_do_lowpower(cpu, &spurious); - - /* - * bring this CPU back into the world of cache - * coherency, and then restore interrupts - */ - cpu_leave_lowpower(); - - if (spurious) - pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious); -} diff --git a/arch/arm/mach-oxnas/platsmp.c b/arch/arm/mach-oxnas/platsmp.c index 442cc8a2f7dc..735141c0e3a3 100644 --- a/arch/arm/mach-oxnas/platsmp.c +++ b/arch/arm/mach-oxnas/platsmp.c @@ -19,7 +19,6 @@ #include extern void ox820_secondary_startup(void); -extern void ox820_cpu_die(unsigned int cpu); static void __iomem *cpu_ctrl; static void __iomem *gic_cpu_ctrl; @@ -94,9 +93,6 @@ static void __init ox820_smp_prepare_cpus(unsigned int max_cpus) static const struct smp_operations ox820_smp_ops __initconst = { .smp_prepare_cpus = ox820_smp_prepare_cpus, .smp_boot_secondary = ox820_boot_secondary, -#ifdef CONFIG_HOTPLUG_CPU - .cpu_die = ox820_cpu_die, -#endif }; CPU_METHOD_OF_DECLARE(ox820_smp, "oxsemi,ox820-smp", &ox820_smp_ops); From patchwork Thu Dec 13 18:00:57 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Russell King (Oracle)" X-Patchwork-Id: 10729479 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D36856C5 for ; Thu, 13 Dec 2018 18:13:49 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BF5D2286B2 for ; Thu, 13 Dec 2018 18:13:49 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AEF0B28CAC; Thu, 13 Dec 2018 18:13:49 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SORTED_RECIPS, SUSPICIOUS_RECIPS autolearn=no version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 19E7F286B2 for ; Thu, 13 Dec 2018 18:13:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Date:Message-Id:MIME-Version:Subject:To :From:References:In-Reply-To:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=f1nhGjaRUiKgIM+vZ/frNoRbuEZA7ujCLiyoxOsH3Jw=; b=VK7O/sP/6ULM1y ba63ClE1p9TauacU5TU7ei1IlZpBvY/q3F/4WWMHHioVJueWLn5ObFvh1wbj3o8ISz33kmCKHEh4m Qb2AsEf0btVOS8x47br4s2mogxoJkbS1acyDF/KnhF7emmCzhBhxeQz8Bc8v4bLzO2eaMyyq/ga0K pWWsR368/hgcIgFMdtEviUue4wDere3lLV3h1EnP9aUMUWjy0kvpvSlZfS5N/Zx9mxtbO38vgqNKJ AvTlMdBUWjjDFO4iXTNsQiSeXMT4iUeR3meOlT3SoplUN45k5vpOX0u2soDoSmHeWkay4StmUJzaF H8fFa/BnIBuwUwaNIPLw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVUZ-0005sp-UA; Thu, 13 Dec 2018 18:13:47 +0000 Received: from pandora.armlinux.org.uk ([2001:4d48:ad52:3201:214:fdff:fe10:1be6]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVIO-00068A-GW for linux-arm-kernel@lists.infradead.org; Thu, 13 Dec 2018 18:01:17 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2014; h=Date:Sender:Message-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References: In-Reply-To:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=/ytTiQYVG3g6vcew3RCoHF4lBQZyfASgL8KIPRbyLzw=; b=WzGp03rpHEuKUXgGlpiYn6ug36 JcHm9gdkc8FZAdjy70rK09pg11Pni8REUC6qhRDjSab5oZ0NKpNImJ1cNK0g0pE1Z0bjPcTitJUZw I3kl5BCXwyAohhqeGopMm5x8Z1ymAT9t/hOCs/8bRstZH3zuSOQCvOsMj56T4d020JQM=; Received: from e0022681537dd.dyn.armlinux.org.uk ([fd8f:7570:feb6:1:222:68ff:fe15:37dd]:49260 helo=rmk-PC.armlinux.org.uk) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.90_1) (envelope-from ) id 1gXVIA-0003sQ-UZ; Thu, 13 Dec 2018 18:00:59 +0000 Received: from rmk by rmk-PC.armlinux.org.uk with local (Exim 4.82_1-5b7a7c0-XX) (envelope-from ) id 1gXVI9-000897-25; Thu, 13 Dec 2018 18:00:57 +0000 In-Reply-To: <20181213175952.GC26090@n2100.armlinux.org.uk> References: <20181213175952.GC26090@n2100.armlinux.org.uk> From: Russell King To: linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-omap@vger.kernel.org, linux-oxnas@groups.io, linux-samsung-soc@vger.kernel.org, linux-soc@vger.kernel.org Subject: [PATCH 4/9] ARM: sti: remove pen_release and boot_lock MIME-Version: 1.0 Content-Disposition: inline Message-Id: Date: Thu, 13 Dec 2018 18:00:57 +0000 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181213_100112_816497_0E4F85FD X-CRM114-Status: GOOD ( 19.46 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Patrice Chotard Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The pen_release implementation was created for Versatile platforms to work around boot loaders that did not differentiate between the various different secondary CPUs on this ARM development platform. This should not be true of modern platforms where we send IPIs to specific CPUs to wake them up. Remove the pen_release stuff from SoCs that make use of the per-CPU IPI mechanism. The boot_lock is something that was required for ARM development platforms to ensure that the delay calibration worked properly. This is not necessary for modern platforms that have better bus bandwidth and do not need to calibrate the delay loop for secondary cores. Remove the boot_lock entirely. Signed-off-by: Russell King --- arch/arm/mach-sti/Makefile | 2 +- arch/arm/mach-sti/headsmp.S | 43 ------------------------------- arch/arm/mach-sti/platsmp.c | 62 ++------------------------------------------- 3 files changed, 3 insertions(+), 104 deletions(-) delete mode 100644 arch/arm/mach-sti/headsmp.S diff --git a/arch/arm/mach-sti/Makefile b/arch/arm/mach-sti/Makefile index acb330916333..f85ff059cfba 100644 --- a/arch/arm/mach-sti/Makefile +++ b/arch/arm/mach-sti/Makefile @@ -1,2 +1,2 @@ -obj-$(CONFIG_SMP) += platsmp.o headsmp.o +obj-$(CONFIG_SMP) += platsmp.o obj-$(CONFIG_ARCH_STI) += board-dt.o diff --git a/arch/arm/mach-sti/headsmp.S b/arch/arm/mach-sti/headsmp.S deleted file mode 100644 index e0ad451700d5..000000000000 --- a/arch/arm/mach-sti/headsmp.S +++ /dev/null @@ -1,43 +0,0 @@ -/* - * arch/arm/mach-sti/headsmp.S - * - * Copyright (C) 2013 STMicroelectronics (R&D) Limited. - * http://www.st.com - * - * Cloned from linux/arch/arm/mach-vexpress/headsmp.S - * - * Copyright (c) 2003 ARM Limited - * All Rights Reserved - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ -#include -#include - -/* - * ST specific entry point for secondary CPUs. This provides - * a "holding pen" into which all secondary cores are held until we're - * ready for them to initialise. - */ -ENTRY(sti_secondary_startup) - mrc p15, 0, r0, c0, c0, 5 - and r0, r0, #15 - adr r4, 1f - ldmia r4, {r5, r6} - sub r4, r4, r5 - add r6, r6, r4 -pen: ldr r7, [r6] - cmp r7, r0 - bne pen - - /* - * we've been released from the holding pen: secondary_stack - * should now contain the SVC stack for this core - */ - b secondary_startup -ENDPROC(sti_secondary_startup) - -1: .long . - .long pen_release diff --git a/arch/arm/mach-sti/platsmp.c b/arch/arm/mach-sti/platsmp.c index 231f19e17436..21668501c9bb 100644 --- a/arch/arm/mach-sti/platsmp.c +++ b/arch/arm/mach-sti/platsmp.c @@ -28,72 +28,15 @@ #include "smp.h" -static void write_pen_release(int val) -{ - pen_release = val; - smp_wmb(); - sync_cache_w(&pen_release); -} - -static DEFINE_SPINLOCK(boot_lock); - -static void sti_secondary_init(unsigned int cpu) -{ - /* - * let the primary processor know we're out of the - * pen, then head off into the C entry point - */ - write_pen_release(-1); - - /* - * Synchronise with the boot thread. - */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); -} - static int sti_boot_secondary(unsigned int cpu, struct task_struct *idle) { - unsigned long timeout; - - /* - * set synchronisation state between this boot processor - * and the secondary one - */ - spin_lock(&boot_lock); - - /* - * The secondary processor is waiting to be released from - * the holding pen - release it, then wait for it to flag - * that it has been released by resetting pen_release. - * - * Note that "pen_release" is the hardware CPU ID, whereas - * "cpu" is Linux's internal ID. - */ - write_pen_release(cpu_logical_map(cpu)); - /* * Send the secondary CPU a soft interrupt, thereby causing * it to jump to the secondary entrypoint. */ arch_send_wakeup_ipi_mask(cpumask_of(cpu)); - timeout = jiffies + (1 * HZ); - while (time_before(jiffies, timeout)) { - smp_rmb(); - if (pen_release == -1) - break; - - udelay(10); - } - - /* - * now the secondary core is starting up let it run its - * calibrations, then wait for it to finish - */ - spin_unlock(&boot_lock); - - return pen_release != -1 ? -ENOSYS : 0; + return 0; } static void __init sti_smp_prepare_cpus(unsigned int max_cpus) @@ -103,7 +46,7 @@ static void __init sti_smp_prepare_cpus(unsigned int max_cpus) u32 __iomem *cpu_strt_ptr; u32 release_phys; int cpu; - unsigned long entry_pa = __pa_symbol(sti_secondary_startup); + unsigned long entry_pa = __pa_symbol(secondary_startup); np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu"); @@ -158,6 +101,5 @@ static void __init sti_smp_prepare_cpus(unsigned int max_cpus) const struct smp_operations sti_smp_ops __initconst = { .smp_prepare_cpus = sti_smp_prepare_cpus, - .smp_secondary_init = sti_secondary_init, .smp_boot_secondary = sti_boot_secondary, }; From patchwork Thu Dec 13 18:01:02 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Russell King (Oracle)" X-Patchwork-Id: 10729469 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 6D9E913BF for ; Thu, 13 Dec 2018 18:02:14 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5E36A2C4D7 for ; Thu, 13 Dec 2018 18:02:14 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 529882C80A; Thu, 13 Dec 2018 18:02:14 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id D1F222C4D7 for ; Thu, 13 Dec 2018 18:02:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Date:Message-Id:MIME-Version:Subject:To :From:References:In-Reply-To:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=JpynyDNp/yyJa3EbBX/Ms8tccxLSeH78kYku0cIsJcQ=; b=GlmNItL42N7xt1 wcgg2+ac1dbniK2EGfnYldXVEHzujlnZkm1WVp0Lyp3X7RJJVMmbYevk8l3r83zI3jfucpuqRhVwS SaA4lOkottSGlf3BCVC4yL/93eRb5H+uFlx0DvA54y/zt/A73lvFJ0o8CeeWUntp22RX1c2THKXgY lCfPN46w6gzNHgsxbiAzZNhpYgigI37VlKeo1FSEC89wHPyU0IFuyryb5zy9v19tw66iKJyW+fXii frajRIfur1+aRCzlt79bZHJ7mNLed4BQQw86x5WcoIsLyEEIaaAPy3MlEkqmnDV71czcuTwVJHs00 YS+4nbMgcZyjSUisBaSA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVJM-00074I-9P; Thu, 13 Dec 2018 18:02:12 +0000 Received: from pandora.armlinux.org.uk ([2001:4d48:ad52:3201:214:fdff:fe10:1be6]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVIe-0006EF-BC for linux-arm-kernel@lists.infradead.org; Thu, 13 Dec 2018 18:01:46 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2014; h=Date:Sender:Message-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References: In-Reply-To:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=3Es9RBnn1L2qTSYe0DphuXplYjpi9l2zhl/9K/iit8o=; b=KflLq8Qr0ZdMPkxHKP+GQBCLRi DCQPFtcdIjJ7HK+GbUV2teYrRXvZ9AIQse/CfbWyU725bMDQ51OQ+yxzT7g+nxBVelyW8SC/DrWi1 djTttIQC5owQix+3M3MTp/muZiPaZ/NgvyUTupqVyHhc7TywFJZXLWdG3LSbUlq4Hnhg=; Received: from e0022681537dd.dyn.armlinux.org.uk ([fd8f:7570:feb6:1:222:68ff:fe15:37dd]:49262 helo=rmk-PC.armlinux.org.uk) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.90_1) (envelope-from ) id 1gXVIG-0003sh-K6; Thu, 13 Dec 2018 18:01:04 +0000 Received: from rmk by rmk-PC.armlinux.org.uk with local (Exim 4.82_1-5b7a7c0-XX) (envelope-from ) id 1gXVIE-0008CK-5O; Thu, 13 Dec 2018 18:01:02 +0000 In-Reply-To: <20181213175952.GC26090@n2100.armlinux.org.uk> References: <20181213175952.GC26090@n2100.armlinux.org.uk> From: Russell King To: linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-omap@vger.kernel.org, linux-oxnas@groups.io, linux-samsung-soc@vger.kernel.org, linux-soc@vger.kernel.org Subject: [PATCH 5/9] ARM: actions: remove boot_lock and pen_release MIME-Version: 1.0 Content-Disposition: inline Message-Id: Date: Thu, 13 Dec 2018 18:01:02 +0000 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181213_100128_958820_38300A3A X-CRM114-Status: GOOD ( 10.36 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: =?unknown-8bit?q?Andreas_F=C3=A4rber_=3Cafaerber=40suse=2Ede=3E=2C_Maniv?= =?unknown-8bit?q?annan_Sadhasivam_=3Cmanivannan=2Esadhasivam=40linaro=2Eorg?= =?unknown-8bit?q?=3E?= Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The actions SMP implementation has several issues: 1. pen_release is only ever read and compared to -1, and is defined in arch/arm/kernel/smp.c to be -1. This test will always succeed. 2. we are already guaranteed to be single threaded while bringing up a CPU, so the spinlock makes no sense, remove it. 3. owl_secondary_startup() is not referenced nor defined, the prototype is redundant, remove it. Signed-off-by: Russell King --- arch/arm/mach-actions/platsmp.c | 15 --------------- 1 file changed, 15 deletions(-) diff --git a/arch/arm/mach-actions/platsmp.c b/arch/arm/mach-actions/platsmp.c index 3efaa10efc43..4fd479c948e6 100644 --- a/arch/arm/mach-actions/platsmp.c +++ b/arch/arm/mach-actions/platsmp.c @@ -39,10 +39,6 @@ static void __iomem *sps_base_addr; static void __iomem *timer_base_addr; static int ncores; -static DEFINE_SPINLOCK(boot_lock); - -void owl_secondary_startup(void); - static int s500_wakeup_secondary(unsigned int cpu) { int ret; @@ -84,7 +80,6 @@ static int s500_wakeup_secondary(unsigned int cpu) static int s500_smp_boot_secondary(unsigned int cpu, struct task_struct *idle) { - unsigned long timeout; int ret; ret = s500_wakeup_secondary(cpu); @@ -93,21 +88,11 @@ static int s500_smp_boot_secondary(unsigned int cpu, struct task_struct *idle) udelay(10); - spin_lock(&boot_lock); - smp_send_reschedule(cpu); - timeout = jiffies + (1 * HZ); - while (time_before(jiffies, timeout)) { - if (pen_release == -1) - break; - } - writel(0, timer_base_addr + OWL_CPU1_ADDR + (cpu - 1) * 4); writel(0, timer_base_addr + OWL_CPU1_FLAG + (cpu - 1) * 4); - spin_unlock(&boot_lock); - return 0; } From patchwork Thu Dec 13 18:01:07 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Russell King (Oracle)" X-Patchwork-Id: 10729471 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 06C7C13BF for ; Thu, 13 Dec 2018 18:02:32 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E7E382C80A for ; Thu, 13 Dec 2018 18:02:31 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id DA3682C811; Thu, 13 Dec 2018 18:02:31 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id E618F2C80A for ; Thu, 13 Dec 2018 18:02:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Date:Message-Id:MIME-Version:Subject:To :From:References:In-Reply-To:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=UXsjMtD6j5pNhJjWy90GFmATCq9UkpL2++EF7n6dPB4=; b=FeqZ0H68Levr0V IzbsS6XchGLCbhQr7HrzjWoTOPu3cx52gNSyKXJSf2kezwTFZFdlv3pLmcUMaAjVxr10F0Bul6Rip q2gCvcDWnDRXM9JctByF8hIxmY4bcHtwawMbw6iD0GJ20IwsvCA4ti4lURGlvx6B8nfUq/Q7l2lYk FVaO5BV/XnbHUItnjizRuR26E9IRBAFx1V547QEOnmMiUlzLW/NxD8cruqmQClW5KtlzxQ0vLGAwK s1QS0XexB52jNo6KW9ZR7hk/R0GVjSHI7Rzl9+nzfy78xYSVq4nI7IWaAWpEB+q0ameRQooQ2/z6a hNYwdZ0Z/leGeXJnDOkw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVJZ-0007IM-Sn; Thu, 13 Dec 2018 18:02:25 +0000 Received: from pandora.armlinux.org.uk ([2001:4d48:ad52:3201:214:fdff:fe10:1be6]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVIe-0006LA-BI for linux-arm-kernel@lists.infradead.org; Thu, 13 Dec 2018 18:01:47 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2014; h=Date:Sender:Message-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References: In-Reply-To:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=uNIYWf2j1x5/qS8a1yQoNYRtodGWwHtrqWOONaztyCs=; b=YsgX6b5PEhIQNPo3PwXeOC4OKG 9Ilvpel6TxqVaf4f5oaUZbzv5z+GlHAz1p/YgRR8vShyV3/JhYZCwrbqkVDRdTzEe2gy4INEen9dJ Tjer0gB9D8lx3cTGl8y3UtnNqWN2DTBFjCJgDe5vUJoESFC1RtkR7i4Vl0Jb2QfqnUJM=; Received: from e0022681537dd.dyn.armlinux.org.uk ([2001:4d48:ad52:3201:222:68ff:fe15:37dd]:59208 helo=rmk-PC.armlinux.org.uk) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.90_1) (envelope-from ) id 1gXVIL-0003t4-Gu; Thu, 13 Dec 2018 18:01:09 +0000 Received: from rmk by rmk-PC.armlinux.org.uk with local (Exim 4.82_1-5b7a7c0-XX) (envelope-from ) id 1gXVIJ-0008CX-8y; Thu, 13 Dec 2018 18:01:07 +0000 In-Reply-To: <20181213175952.GC26090@n2100.armlinux.org.uk> References: <20181213175952.GC26090@n2100.armlinux.org.uk> From: Russell King To: linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-omap@vger.kernel.org, linux-oxnas@groups.io, linux-samsung-soc@vger.kernel.org, linux-soc@vger.kernel.org Subject: [PATCH 6/9] ARM: vexpress/realview: consolidate immitation CPU hotplug MIME-Version: 1.0 Content-Disposition: inline Message-Id: Date: Thu, 13 Dec 2018 18:01:07 +0000 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181213_100129_307028_507410F8 X-CRM114-Status: GOOD ( 19.27 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Linus Walleij , Lorenzo Pieralisi , Liviu Dudau , Sudeep Holla Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The only difference between the hotplug implementation for Realview and Versatile Express are the bit in the auxiliary control register to disable coherency. Combine the two implentations accounting for that difference. Rename the functions to try to discourage cargo-cult copying of this code. Tested-by: Sudeep Holla Acked-by: Sudeep Holla Signed-off-by: Russell King --- arch/arm/mach-realview/Makefile | 1 - arch/arm/mach-realview/hotplug.c | 111 --------------------- arch/arm/mach-realview/hotplug.h | 1 - arch/arm/mach-realview/platsmp-dt.c | 8 +- arch/arm/mach-vexpress/Makefile | 1 - arch/arm/mach-vexpress/core.h | 2 - arch/arm/mach-vexpress/platsmp.c | 7 ++ arch/arm/plat-versatile/Makefile | 1 + .../{mach-vexpress => plat-versatile}/hotplug.c | 45 ++++----- arch/arm/plat-versatile/include/plat/platsmp.h | 1 + 10 files changed, 36 insertions(+), 142 deletions(-) delete mode 100644 arch/arm/mach-realview/hotplug.c delete mode 100644 arch/arm/mach-realview/hotplug.h rename arch/arm/{mach-vexpress => plat-versatile}/hotplug.c (58%) diff --git a/arch/arm/mach-realview/Makefile b/arch/arm/mach-realview/Makefile index adf39ad71cc3..6ca6400fa51e 100644 --- a/arch/arm/mach-realview/Makefile +++ b/arch/arm/mach-realview/Makefile @@ -5,4 +5,3 @@ ccflags-$(CONFIG_ARCH_MULTIPLATFORM) := -I$(srctree)/arch/arm/plat-versatile/inc obj-y += realview-dt.o obj-$(CONFIG_SMP) += platsmp-dt.o -obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o diff --git a/arch/arm/mach-realview/hotplug.c b/arch/arm/mach-realview/hotplug.c deleted file mode 100644 index 968e2d1964f6..000000000000 --- a/arch/arm/mach-realview/hotplug.c +++ /dev/null @@ -1,111 +0,0 @@ -/* - * linux/arch/arm/mach-realview/hotplug.c - * - * Copyright (C) 2002 ARM Ltd. - * All Rights Reserved - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ -#include -#include -#include - -#include -#include - -static inline void cpu_enter_lowpower(void) -{ - unsigned int v; - - asm volatile( - " mcr p15, 0, %1, c7, c5, 0\n" - " mcr p15, 0, %1, c7, c10, 4\n" - /* - * Turn off coherency - */ - " mrc p15, 0, %0, c1, c0, 1\n" - " bic %0, %0, #0x20\n" - " mcr p15, 0, %0, c1, c0, 1\n" - " mrc p15, 0, %0, c1, c0, 0\n" - " bic %0, %0, %2\n" - " mcr p15, 0, %0, c1, c0, 0\n" - : "=&r" (v) - : "r" (0), "Ir" (CR_C) - : "cc"); -} - -static inline void cpu_leave_lowpower(void) -{ - unsigned int v; - - asm volatile( "mrc p15, 0, %0, c1, c0, 0\n" - " orr %0, %0, %1\n" - " mcr p15, 0, %0, c1, c0, 0\n" - " mrc p15, 0, %0, c1, c0, 1\n" - " orr %0, %0, #0x20\n" - " mcr p15, 0, %0, c1, c0, 1\n" - : "=&r" (v) - : "Ir" (CR_C) - : "cc"); -} - -static inline void platform_do_lowpower(unsigned int cpu, int *spurious) -{ - /* - * there is no power-control hardware on this platform, so all - * we can do is put the core into WFI; this is safe as the calling - * code will have already disabled interrupts - */ - for (;;) { - /* - * here's the WFI - */ - asm(".word 0xe320f003\n" - : - : - : "memory", "cc"); - - if (pen_release == cpu_logical_map(cpu)) { - /* - * OK, proper wakeup, we're done - */ - break; - } - - /* - * Getting here, means that we have come out of WFI without - * having been woken up - this shouldn't happen - * - * Just note it happening - when we're woken, we can report - * its occurrence. - */ - (*spurious)++; - } -} - -/* - * platform-specific code to shutdown a CPU - * - * Called with IRQs disabled - */ -void realview_cpu_die(unsigned int cpu) -{ - int spurious = 0; - - /* - * we're ready for shutdown now, so do it - */ - cpu_enter_lowpower(); - platform_do_lowpower(cpu, &spurious); - - /* - * bring this CPU back into the world of cache - * coherency, and then restore interrupts - */ - cpu_leave_lowpower(); - - if (spurious) - pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious); -} diff --git a/arch/arm/mach-realview/hotplug.h b/arch/arm/mach-realview/hotplug.h deleted file mode 100644 index eacd7a4dad2f..000000000000 --- a/arch/arm/mach-realview/hotplug.h +++ /dev/null @@ -1 +0,0 @@ -void realview_cpu_die(unsigned int cpu); diff --git a/arch/arm/mach-realview/platsmp-dt.c b/arch/arm/mach-realview/platsmp-dt.c index c242423bf8db..ce331b3dbf54 100644 --- a/arch/arm/mach-realview/platsmp-dt.c +++ b/arch/arm/mach-realview/platsmp-dt.c @@ -17,7 +17,6 @@ #include #include -#include "hotplug.h" #define REALVIEW_SYS_FLAGSSET_OFFSET 0x30 @@ -79,6 +78,13 @@ static void __init realview_smp_prepare_cpus(unsigned int max_cpus) __pa_symbol(versatile_secondary_startup)); } +#ifdef CONFIG_HOTPLUG_CPU +static void realview_cpu_die(unsigned int cpu) +{ + return versatile_immitation_cpu_die(cpu, 0x20); +} +#endif + static const struct smp_operations realview_dt_smp_ops __initconst = { .smp_prepare_cpus = realview_smp_prepare_cpus, .smp_secondary_init = versatile_secondary_init, diff --git a/arch/arm/mach-vexpress/Makefile b/arch/arm/mach-vexpress/Makefile index 51c35e2b737a..3651a1ed0f2b 100644 --- a/arch/arm/mach-vexpress/Makefile +++ b/arch/arm/mach-vexpress/Makefile @@ -15,6 +15,5 @@ obj-$(CONFIG_ARCH_VEXPRESS_TC2_PM) += tc2_pm.o CFLAGS_tc2_pm.o += -march=armv7-a CFLAGS_REMOVE_tc2_pm.o = -pg obj-$(CONFIG_SMP) += platsmp.o -obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o obj-$(CONFIG_ARCH_MPS2) += v2m-mps2.o diff --git a/arch/arm/mach-vexpress/core.h b/arch/arm/mach-vexpress/core.h index a162ab46ee02..f4a7519084f1 100644 --- a/arch/arm/mach-vexpress/core.h +++ b/arch/arm/mach-vexpress/core.h @@ -1,5 +1,3 @@ bool vexpress_smp_init_ops(void); extern const struct smp_operations vexpress_smp_dt_ops; - -extern void vexpress_cpu_die(unsigned int cpu); diff --git a/arch/arm/mach-vexpress/platsmp.c b/arch/arm/mach-vexpress/platsmp.c index 742499bac6d0..af0113be5970 100644 --- a/arch/arm/mach-vexpress/platsmp.c +++ b/arch/arm/mach-vexpress/platsmp.c @@ -82,6 +82,13 @@ static void __init vexpress_smp_dt_prepare_cpus(unsigned int max_cpus) vexpress_flags_set(__pa_symbol(versatile_secondary_startup)); } +#ifdef CONFIG_HOTPLUG_CPU +static void vexpress_cpu_die(unsigned int cpu) +{ + versatile_immitation_cpu_die(cpu, 0x40); +} +#endif + const struct smp_operations vexpress_smp_dt_ops __initconst = { .smp_prepare_cpus = vexpress_smp_dt_prepare_cpus, .smp_secondary_init = versatile_secondary_init, diff --git a/arch/arm/plat-versatile/Makefile b/arch/arm/plat-versatile/Makefile index bff3ba889882..b2f0ddfdc4cc 100644 --- a/arch/arm/plat-versatile/Makefile +++ b/arch/arm/plat-versatile/Makefile @@ -2,3 +2,4 @@ ccflags-$(CONFIG_ARCH_MULTIPLATFORM) := -I$(srctree)/$(src)/include obj-$(CONFIG_PLAT_VERSATILE_SCHED_CLOCK) += sched-clock.o obj-$(CONFIG_SMP) += headsmp.o platsmp.o +obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o diff --git a/arch/arm/mach-vexpress/hotplug.c b/arch/arm/plat-versatile/hotplug.c similarity index 58% rename from arch/arm/mach-vexpress/hotplug.c rename to arch/arm/plat-versatile/hotplug.c index d8f1a05f5e87..e2d3e9035d0f 100644 --- a/arch/arm/mach-vexpress/hotplug.c +++ b/arch/arm/plat-versatile/hotplug.c @@ -1,12 +1,15 @@ /* - * linux/arch/arm/mach-realview/hotplug.c - * * Copyright (C) 2002 ARM Ltd. * All Rights Reserved * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. + * + * This hotplug implementation is _specific_ to the situation found on + * ARM development platforms where there is _no_ possibility of actually + * taking a CPU offline, resetting it, or otherwise. Real platforms must + * NOT copy this code. */ #include #include @@ -15,9 +18,7 @@ #include #include -#include "core.h" - -static inline void cpu_enter_lowpower(void) +static inline void versatile_immitation_enter_lowpower(unsigned int actrl_mask) { unsigned int v; @@ -34,11 +35,11 @@ static inline void cpu_enter_lowpower(void) " bic %0, %0, %2\n" " mcr p15, 0, %0, c1, c0, 0\n" : "=&r" (v) - : "r" (0), "Ir" (CR_C), "Ir" (0x40) + : "r" (0), "Ir" (CR_C), "Ir" (actrl_mask) : "cc"); } -static inline void cpu_leave_lowpower(void) +static inline void versatile_immitation_leave_lowpower(unsigned int actrl_mask) { unsigned int v; @@ -50,16 +51,18 @@ static inline void cpu_leave_lowpower(void) " orr %0, %0, %2\n" " mcr p15, 0, %0, c1, c0, 1\n" : "=&r" (v) - : "Ir" (CR_C), "Ir" (0x40) + : "Ir" (CR_C), "Ir" (actrl_mask) : "cc"); } -static inline void platform_do_lowpower(unsigned int cpu, int *spurious) +static inline void versatile_immitation_do_lowpower(unsigned int cpu, int *spurious) { /* * there is no power-control hardware on this platform, so all * we can do is put the core into WFI; this is safe as the calling - * code will have already disabled interrupts + * code will have already disabled interrupts. + * + * This code should not be used outside Versatile platforms. */ for (;;) { wfi(); @@ -83,25 +86,17 @@ static inline void platform_do_lowpower(unsigned int cpu, int *spurious) } /* - * platform-specific code to shutdown a CPU - * - * Called with IRQs disabled + * platform-specific code to shutdown a CPU. + * This code supports immitation-style CPU hotplug for Versatile/Realview/ + * Versatile Express platforms that are unable to do real CPU hotplug. */ -void vexpress_cpu_die(unsigned int cpu) +void versatile_immitation_cpu_die(unsigned int cpu, unsigned int actrl_mask) { int spurious = 0; - /* - * we're ready for shutdown now, so do it - */ - cpu_enter_lowpower(); - platform_do_lowpower(cpu, &spurious); - - /* - * bring this CPU back into the world of cache - * coherency, and then restore interrupts - */ - cpu_leave_lowpower(); + versatile_immitation_enter_lowpower(actrl_mask); + versatile_immitation_do_lowpower(cpu, &spurious); + versatile_immitation_leave_lowpower(actrl_mask); if (spurious) pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious); diff --git a/arch/arm/plat-versatile/include/plat/platsmp.h b/arch/arm/plat-versatile/include/plat/platsmp.h index 50fb830192e0..9fff1f241c9e 100644 --- a/arch/arm/plat-versatile/include/plat/platsmp.h +++ b/arch/arm/plat-versatile/include/plat/platsmp.h @@ -12,3 +12,4 @@ extern void versatile_secondary_startup(void); extern void versatile_secondary_init(unsigned int cpu); extern int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle); +void versatile_immitation_cpu_die(unsigned int cpu, unsigned int actrl_mask); From patchwork Thu Dec 13 18:01:12 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Russell King (Oracle)" X-Patchwork-Id: 10729473 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 58E9F13AF for ; Thu, 13 Dec 2018 18:03:09 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4752C2C80A for ; Thu, 13 Dec 2018 18:03:09 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 39DAB2C811; Thu, 13 Dec 2018 18:03:09 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.7 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SUSPICIOUS_RECIPS autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id DA8422C80A for ; Thu, 13 Dec 2018 18:03:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Date:Message-Id:MIME-Version:Subject:To :From:References:In-Reply-To:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=j+L+Og6zBka9cOWzluIsj3QG/7ExqIWjNahsSaFF8Hc=; b=ueeWNhPVBwuhNr ZD9GtMJEQ3Xxj5smvJTTMDdzcI50OHHiRGRwSowvh7tFIofbPeAAR3W6h4XIx8r7k1R5sH7cB1I4m i7Omvw9fDgYix0VRVSGq/qeBjxJA7LYxCPewgBOfcI3OnHl2CPpIil97U1VnT744bmdQxXuVeehzU rz9O3v0j6nu5pyLg3RHeoQjwXQoj7DXq7kaYjfuJxsjlHsyB9QnyqYbak8IFR3Vl960fgUPy6AijT rOpARSaYlDL/xuT3KS2rM4LL3SYzOaMrFvWorpwPxfDF+S66bk2OKk0GpZMmXgI62m+hW+SoCmSCH auFDVkSRC7kBDmJRc/nQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVK8-0007o8-EY; Thu, 13 Dec 2018 18:03:00 +0000 Received: from pandora.armlinux.org.uk ([2001:4d48:ad52:3201:214:fdff:fe10:1be6]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVIs-0006Ri-7w for linux-arm-kernel@lists.infradead.org; Thu, 13 Dec 2018 18:01:56 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2014; h=Date:Sender:Message-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References: In-Reply-To:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=u8iyJzlceG3MnleS1QUeQGTVSonKlGF6GrwmyXojBUo=; b=bJ6N74e/cJ3EWmvLOhyPtYFRs+ P0XdHLqwXt2a48WwCfIf06KkhtQvRTDrhoedNA/0nr7qWWn8VjuR9WgEqQ4nZu0q6WJQzQBFVyNYt Ld/g0LRomkFS+JxqpA9SSoE9TBJa/wtmLqljOrEAaTd8p6zTiOZYLtCF72Gw+QtfhhRw=; Received: from e0022681537dd.dyn.armlinux.org.uk ([2001:4d48:ad52:3201:222:68ff:fe15:37dd]:59210 helo=rmk-PC.armlinux.org.uk) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.90_1) (envelope-from ) id 1gXVIR-0003tC-I0; Thu, 13 Dec 2018 18:01:15 +0000 Received: from rmk by rmk-PC.armlinux.org.uk with local (Exim 4.82_1-5b7a7c0-XX) (envelope-from ) id 1gXVIO-0008Cn-DO; Thu, 13 Dec 2018 18:01:12 +0000 In-Reply-To: <20181213175952.GC26090@n2100.armlinux.org.uk> References: <20181213175952.GC26090@n2100.armlinux.org.uk> From: Russell King To: linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-omap@vger.kernel.org, linux-oxnas@groups.io, linux-samsung-soc@vger.kernel.org, linux-soc@vger.kernel.org Subject: [PATCH 7/9] ARM: versatile: convert boot_lock to raw MIME-Version: 1.0 Content-Disposition: inline Message-Id: Date: Thu, 13 Dec 2018 18:01:12 +0000 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181213_100143_306315_9F251DEE X-CRM114-Status: GOOD ( 14.69 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Linus Walleij Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Sebastian Andrzej Siewior The arm boot_lock is used by the secondary processor startup code. The locking task is the idle thread, which has idle->sched_class == &idle_sched_class. idle_sched_class->enqueue_task == NULL, so if the idle task blocks on the lock, the attempt to wake it when the lock becomes available will fail: try_to_wake_up() ... activate_task() enqueue_task() p->sched_class->enqueue_task(rq, p, flags) Fix by converting boot_lock to a raw spin lock. Cc: Linus Walleij Signed-off-by: Frank Rowand Link: http://lkml.kernel.org/r/4E77B952.3010606@am.sony.com Signed-off-by: Thomas Gleixner Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Russell King --- arch/arm/plat-versatile/platsmp.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/arch/arm/plat-versatile/platsmp.c b/arch/arm/plat-versatile/platsmp.c index c2366510187a..6b60f582b738 100644 --- a/arch/arm/plat-versatile/platsmp.c +++ b/arch/arm/plat-versatile/platsmp.c @@ -32,7 +32,7 @@ static void write_pen_release(int val) sync_cache_w(&pen_release); } -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); void versatile_secondary_init(unsigned int cpu) { @@ -45,8 +45,8 @@ void versatile_secondary_init(unsigned int cpu) /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle) @@ -57,7 +57,7 @@ int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle) * Set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * This is really belt and braces; we hold unintended secondary @@ -87,7 +87,7 @@ int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle) * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } From patchwork Thu Dec 13 18:01:17 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Russell King (Oracle)" X-Patchwork-Id: 10729477 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D795B13AF for ; Thu, 13 Dec 2018 18:04:12 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C1DFD2BF53 for ; Thu, 13 Dec 2018 18:04:12 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B39802C0BF; Thu, 13 Dec 2018 18:04:12 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.7 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SUSPICIOUS_RECIPS autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 17A862BF53 for ; Thu, 13 Dec 2018 18:04:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Date:Message-Id:MIME-Version:Subject:To :From:References:In-Reply-To:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=NYDXOMAJ3e61Ow7vRLnYG9A0xDZsAD7Ka/jbFCVIhZE=; b=nfEgtDeTN+x50r M870TqvPdBcuzYxXzJxZ4S1vWwFe/AoQj8XZ/X1yaIKWr8PA0ALb5jkJw5I8uSztQANZaDtagCgI/ Ak8BLZMwzBakCUHEN95oxQ5GCn7HdFYa/09J+Oz46yOfDcB550DRDjpQOIvJSqisFZUeVoZaYcZwx f7r7TU++A+uWeSx4uGsOdwWEO/4w6ng5rAuV4qDJhO+znjO45LOx85LlHy6mhGzxTTyBwS3P16Fa7 mI53/bGH6gURd62iIYget6AMH47e71qCAtcZhh6OlJMGjk2ykdzBCY7eySSamCOvNdjQJPRQcj9df B7jem0UWePOrc8GKk9Dw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVLB-0000GI-BU; Thu, 13 Dec 2018 18:04:05 +0000 Received: from merlin.infradead.org ([2001:8b0:10b:1231::1]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVL1-0000Dp-U5 for linux-arm-kernel@bombadil.infradead.org; Thu, 13 Dec 2018 18:03:56 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=Date:Sender:Message-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References: In-Reply-To:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=h/5VpWD6jtHCErQoCjlHnGrhBEkBLuBL2tjysdL5d9A=; b=MBuWDEYVtgZTYdXCj2Nvoo2c2/ XC8jsLwmMxO3BsZKg+L3iitxwEiXDyGCDLRT+tnI9tJnTlwyaoClCLi4QRQNooY8F2IpaGO7f6JCG cQSXqFHAzqWKHezDKDQhjy2Ao0s4f4EVmdm9lutOjeh5njrGwPV2esUJZ4415oIeRjSSuRUHU5TmX LYs0bRqoWhQijqV70ucsN+wp7O2Ym7o148d5peKaCwwjJWXttUK+OrN2DLczVlldj+kELQ6EEWdvt J6JI0e8GHJP1/1gbi4Ql7Tebh+3MsJGj5IJlQR9aLN4HcFg27V+ivfzt8Xa+ASEaXQz3r6XXy5RPc DqHVrhZQ==; Received: from pandora.armlinux.org.uk ([2001:4d48:ad52:3201:214:fdff:fe10:1be6]) by merlin.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVKz-0006Gf-2Y for linux-arm-kernel@lists.infradead.org; Thu, 13 Dec 2018 18:03:54 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2014; h=Date:Sender:Message-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References: In-Reply-To:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=h/5VpWD6jtHCErQoCjlHnGrhBEkBLuBL2tjysdL5d9A=; b=VDnNCLi3CE3fWeYqoPSwacr6Ow 08pSUrlsnP28S28pzpmXpuzHt04RaFN1Ac7l+UAHOLH41oBWiY/owZ+ZiRJQzbsIGXXAiB4X0uOpW VKZ28/sIFYvwrVJO7c7Byq5+9+7OT9RsoIqRqdpZkAnu5E9qzzM3acnkwLaV2gVWUH+k=; Received: from e0022681537dd.dyn.armlinux.org.uk ([2001:4d48:ad52:3201:222:68ff:fe15:37dd]:59212 helo=rmk-PC.armlinux.org.uk) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.90_1) (envelope-from ) id 1gXVIV-0003tO-Lr; Thu, 13 Dec 2018 18:01:19 +0000 Received: from rmk by rmk-PC.armlinux.org.uk with local (Exim 4.82_1-5b7a7c0-XX) (envelope-from ) id 1gXVIT-0008D2-IZ; Thu, 13 Dec 2018 18:01:17 +0000 In-Reply-To: <20181213175952.GC26090@n2100.armlinux.org.uk> References: <20181213175952.GC26090@n2100.armlinux.org.uk> From: Russell King To: linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-omap@vger.kernel.org, linux-oxnas@groups.io, linux-samsung-soc@vger.kernel.org, linux-soc@vger.kernel.org Subject: [PATCH 8/9] ARM: versatile: rename and comment SMP implementation MIME-Version: 1.0 Content-Disposition: inline Message-Id: Date: Thu, 13 Dec 2018 18:01:17 +0000 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181213_130353_235135_01CD23DA X-CRM114-Status: GOOD ( 22.42 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Linus Walleij Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Rename pen_release and boot_lock in the Versatile specific SMP implementation, describe why these exist and state clearly that they should not be used in production implementations. Signed-off-by: Russell King --- arch/arm/plat-versatile/headsmp.S | 2 +- arch/arm/plat-versatile/hotplug.c | 4 ++- arch/arm/plat-versatile/include/plat/platsmp.h | 1 + arch/arm/plat-versatile/platsmp.c | 47 ++++++++++++++++++-------- 4 files changed, 38 insertions(+), 16 deletions(-) diff --git a/arch/arm/plat-versatile/headsmp.S b/arch/arm/plat-versatile/headsmp.S index 40f27e52de75..e99396dfa6f3 100644 --- a/arch/arm/plat-versatile/headsmp.S +++ b/arch/arm/plat-versatile/headsmp.S @@ -37,5 +37,5 @@ pen: ldr r7, [r6] .align 1: .long . - .long pen_release + .long versatile_cpu_release ENDPROC(versatile_secondary_startup) diff --git a/arch/arm/plat-versatile/hotplug.c b/arch/arm/plat-versatile/hotplug.c index e2d3e9035d0f..c974958417fe 100644 --- a/arch/arm/plat-versatile/hotplug.c +++ b/arch/arm/plat-versatile/hotplug.c @@ -18,6 +18,8 @@ #include #include +#include + static inline void versatile_immitation_enter_lowpower(unsigned int actrl_mask) { unsigned int v; @@ -67,7 +69,7 @@ static inline void versatile_immitation_do_lowpower(unsigned int cpu, int *spuri for (;;) { wfi(); - if (pen_release == cpu_logical_map(cpu)) { + if (versatile_cpu_release == cpu_logical_map(cpu)) { /* * OK, proper wakeup, we're done */ diff --git a/arch/arm/plat-versatile/include/plat/platsmp.h b/arch/arm/plat-versatile/include/plat/platsmp.h index 9fff1f241c9e..1b087fbbc700 100644 --- a/arch/arm/plat-versatile/include/plat/platsmp.h +++ b/arch/arm/plat-versatile/include/plat/platsmp.h @@ -8,6 +8,7 @@ * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ +extern volatile int versatile_cpu_release; extern void versatile_secondary_startup(void); extern void versatile_secondary_init(unsigned int cpu); diff --git a/arch/arm/plat-versatile/platsmp.c b/arch/arm/plat-versatile/platsmp.c index 6b60f582b738..6e2836243187 100644 --- a/arch/arm/plat-versatile/platsmp.c +++ b/arch/arm/plat-versatile/platsmp.c @@ -7,6 +7,11 @@ * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. + * + * This code is specific to the hardware found on ARM Realview and + * Versatile Express platforms where the CPUs are unable to be individually + * woken, and where there is no way to hot-unplug CPUs. Real platforms + * should not copy this code. */ #include #include @@ -21,18 +26,32 @@ #include /* - * Write pen_release in a way that is guaranteed to be visible to all - * observers, irrespective of whether they're taking part in coherency + * versatile_cpu_release controls the release of CPUs from the holding + * pen in headsmp.S, which exists because we are not always able to + * control the release of individual CPUs from the board firmware. + * Production platforms do not need this. + */ +volatile int versatile_cpu_release = -1; + +/* + * Write versatile_cpu_release in a way that is guaranteed to be visible to + * all observers, irrespective of whether they're taking part in coherency * or not. This is necessary for the hotplug code to work reliably. */ -static void write_pen_release(int val) +static void versatile_write_cpu_release(int val) { - pen_release = val; + versatile_cpu_release = val; smp_wmb(); - sync_cache_w(&pen_release); + sync_cache_w(&versatile_cpu_release); } -static DEFINE_RAW_SPINLOCK(boot_lock); +/* + * versatile_lock exists to avoid running the loops_per_jiffy delay loop + * calibrations on the secondary CPU while the requesting CPU is using + * the limited-bandwidth bus - which affects the calibration value. + * Production platforms do not need this. + */ +static DEFINE_RAW_SPINLOCK(versatile_lock); void versatile_secondary_init(unsigned int cpu) { @@ -40,13 +59,13 @@ void versatile_secondary_init(unsigned int cpu) * let the primary processor know we're out of the * pen, then head off into the C entry point */ - write_pen_release(-1); + versatile_write_cpu_release(-1); /* * Synchronise with the boot thread. */ - raw_spin_lock(&boot_lock); - raw_spin_unlock(&boot_lock); + raw_spin_lock(&versatile_lock); + raw_spin_unlock(&versatile_lock); } int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle) @@ -57,7 +76,7 @@ int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle) * Set synchronisation state between this boot processor * and the secondary one */ - raw_spin_lock(&boot_lock); + raw_spin_lock(&versatile_lock); /* * This is really belt and braces; we hold unintended secondary @@ -65,7 +84,7 @@ int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle) * since we haven't sent them a soft interrupt, they shouldn't * be there. */ - write_pen_release(cpu_logical_map(cpu)); + versatile_write_cpu_release(cpu_logical_map(cpu)); /* * Send the secondary CPU a soft interrupt, thereby causing @@ -77,7 +96,7 @@ int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle) timeout = jiffies + (1 * HZ); while (time_before(jiffies, timeout)) { smp_rmb(); - if (pen_release == -1) + if (versatile_cpu_release == -1) break; udelay(10); @@ -87,7 +106,7 @@ int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle) * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - raw_spin_unlock(&boot_lock); + raw_spin_unlock(&versatile_lock); - return pen_release != -1 ? -ENOSYS : 0; + return versatile_cpu_release != -1 ? -ENOSYS : 0; } From patchwork Thu Dec 13 18:01:22 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Russell King (Oracle)" X-Patchwork-Id: 10729475 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0516413BF for ; Thu, 13 Dec 2018 18:03:20 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E6B932C80A for ; Thu, 13 Dec 2018 18:03:19 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id DA4262C811; Thu, 13 Dec 2018 18:03:19 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id BA4F72C80A for ; Thu, 13 Dec 2018 18:03:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Date:Message-Id:MIME-Version:Subject:To :From:References:In-Reply-To:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=HVj9oLfL/IrED8jaSHVOkVoUVeJmMvPXEbyEvECC+jg=; b=Uc7mBcFFFjuK9e wMEcZkByDbSA3Oa2wIzrZCj3n3GCbV83wOMbhIvrgvXRnS6vyVZ9JHpxqNtkPOezwOVIc9onTOnK8 lvFvlKuzjnIBPYZZx5+lAgtVm/IbP7Kj2OPjWdid5Q9/ZEPWF1wUsSUAAOf2PoNvn85ZBAq4C9We5 Vn1WDl0W/dvx1HjsfW2FLv+7oET6wEDEWAzKbUu9ILECHEDhLYtkjzU1H2cZSDSv/11CVaj9s0Z7b 1+uELy3WdJGAlLoVKu3wQicqeEYag/1zDHsghFPC+CVJYt57ucRFT9vVxtegQXrYDiEqsCzlJ/e2I 3/oSD+6PF1Sqr7Kr2cLA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVKO-00082o-5y; Thu, 13 Dec 2018 18:03:16 +0000 Received: from pandora.armlinux.org.uk ([78.32.30.218]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXVJ1-0006fC-Vm for linux-arm-kernel@lists.infradead.org; Thu, 13 Dec 2018 18:01:59 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2014; h=Date:Sender:Message-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References: In-Reply-To:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=DjQ5GUnGPSsTZB//gUT/RqKcbXjQOu9tn2/wxxwTVOg=; b=AnoRTAaRPb0YTrqxYLeLhOtmQ3 jNfBE6Q2++4GYl9pT841DBMDlugeRgML/vD9P88pNXBaCKrCrS9nWlXib4hFmFQ6sFtjmQjJ9gU+B ydgvGpfYb02R3/o6JXrJHC2bW2MqMaNlOHr4Sf3RtNADGBPszJgmiOq5tCR24JS7zbUc=; Received: from e0022681537dd.dyn.armlinux.org.uk ([2001:4d48:ad52:3201:222:68ff:fe15:37dd]:59214 helo=rmk-PC.armlinux.org.uk) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.90_1) (envelope-from ) id 1gXVIc-0003ta-3y; Thu, 13 Dec 2018 18:01:26 +0000 Received: from rmk by rmk-PC.armlinux.org.uk with local (Exim 4.82_1-5b7a7c0-XX) (envelope-from ) id 1gXVIY-0008DI-MU; Thu, 13 Dec 2018 18:01:22 +0000 In-Reply-To: <20181213175952.GC26090@n2100.armlinux.org.uk> References: <20181213175952.GC26090@n2100.armlinux.org.uk> From: Russell King To: linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-omap@vger.kernel.org, linux-oxnas@groups.io, linux-samsung-soc@vger.kernel.org, linux-soc@vger.kernel.org Subject: [PATCH 9/9] ARM: smp: remove arch-provided "pen_release" MIME-Version: 1.0 Content-Disposition: inline Message-Id: Date: Thu, 13 Dec 2018 18:01:22 +0000 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181213_100152_570231_B40B4EF9 X-CRM114-Status: GOOD ( 23.96 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Viresh Kumar , Barry Song , Kukjin Kim , Shiraz Hashim , Krzysztof Kozlowski Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Consolidating the "pen_release" stuff amongst the various SoC implementations gives credence to having a CPU holding pen for secondary CPUs. However, this is far from the truth. Many SoC implementations cargo-cult copied various bits of the pen release implementation from the initial Realview/Versatile Express implementation without understanding what it was or why it existed. The reason it existed is because these are _development_ platforms, and some board firmware is unable to individually control the startup of secondary CPUs. Moreover, they do not have a way to power down or reset secondary CPUs for hot-unplug. Hence, the pen_release implementation was designed for ARM Ltd's development platforms to provide a working implementation, even though it is very far from what is required. It was decided a while back to reduce the duplication by consolidating the "pen_release" variable, but this only made the situation worse - we have ended up with several implementations that read this variable but do not write it - again, showing the cargo-cult mentality at work, lack of proper review of new code, and in some cases a lack of testing. While it would be preferable to remove pen_release entirely from the kernel, this is not possible without help from the SoC maintainers, which seems to be lacking. However, I want to remove pen_release from arch code to remove the credence that having it gives. This patch removes pen_release from the arch code entirely, adding private per-SoC definitions for it instead, and explicitly stating that write_pen_release() is cargo-cult copied and should not be copied any further. Rename write_pen_release() in a similar fashion as well. Signed-off-by: Russell King --- arch/arm/include/asm/smp.h | 1 - arch/arm/kernel/smp.c | 6 ------ arch/arm/mach-exynos/headsmp.S | 2 +- arch/arm/mach-exynos/platsmp.c | 31 ++++++++++++++++++------------- arch/arm/mach-prima2/common.h | 2 ++ arch/arm/mach-prima2/headsmp.S | 2 +- arch/arm/mach-prima2/hotplug.c | 3 ++- arch/arm/mach-prima2/platsmp.c | 17 ++++++++++------- arch/arm/mach-spear/generic.h | 2 ++ arch/arm/mach-spear/headsmp.S | 2 +- arch/arm/mach-spear/hotplug.c | 4 +++- arch/arm/mach-spear/platsmp.c | 27 ++++++++++++++++----------- 12 files changed, 56 insertions(+), 43 deletions(-) diff --git a/arch/arm/include/asm/smp.h b/arch/arm/include/asm/smp.h index 709a55989cb0..451ae684aaf4 100644 --- a/arch/arm/include/asm/smp.h +++ b/arch/arm/include/asm/smp.h @@ -67,7 +67,6 @@ struct secondary_data { void *stack; }; extern struct secondary_data secondary_data; -extern volatile int pen_release; extern void secondary_startup(void); extern void secondary_startup_arm(void); diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 0978282d5fc2..04aa1bcb8d98 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -61,12 +61,6 @@ */ struct secondary_data secondary_data; -/* - * control for which core is the next to come out of the secondary - * boot "holding pen" - */ -volatile int pen_release = -1; - enum ipi_msg_type { IPI_WAKEUP, IPI_TIMER, diff --git a/arch/arm/mach-exynos/headsmp.S b/arch/arm/mach-exynos/headsmp.S index 005695c9bf40..0ac2cb9a7355 100644 --- a/arch/arm/mach-exynos/headsmp.S +++ b/arch/arm/mach-exynos/headsmp.S @@ -36,4 +36,4 @@ ENDPROC(exynos4_secondary_startup) .align 2 1: .long . - .long pen_release + .long exynos_pen_release diff --git a/arch/arm/mach-exynos/platsmp.c b/arch/arm/mach-exynos/platsmp.c index 6a1e682371b3..76c3f05854e4 100644 --- a/arch/arm/mach-exynos/platsmp.c +++ b/arch/arm/mach-exynos/platsmp.c @@ -28,6 +28,9 @@ extern void exynos4_secondary_startup(void); +/* XXX exynos_pen_release is cargo culted code - DO NOT COPY XXX */ +volatile int exynos_pen_release = -1; + #ifdef CONFIG_HOTPLUG_CPU static inline void cpu_leave_lowpower(u32 core_id) { @@ -57,7 +60,7 @@ static inline void platform_do_lowpower(unsigned int cpu, int *spurious) wfi(); - if (pen_release == core_id) { + if (exynos_pen_release == core_id) { /* * OK, proper wakeup, we're done */ @@ -228,15 +231,17 @@ void exynos_core_restart(u32 core_id) } /* - * Write pen_release in a way that is guaranteed to be visible to all - * observers, irrespective of whether they're taking part in coherency + * XXX CARGO CULTED CODE - DO NOT COPY XXX + * + * Write exynos_pen_release in a way that is guaranteed to be visible to + * all observers, irrespective of whether they're taking part in coherency * or not. This is necessary for the hotplug code to work reliably. */ -static void write_pen_release(int val) +static void exynos_write_pen_release(int val) { - pen_release = val; + exynos_pen_release = val; smp_wmb(); - sync_cache_w(&pen_release); + sync_cache_w(&exynos_pen_release); } static DEFINE_SPINLOCK(boot_lock); @@ -247,7 +252,7 @@ static void exynos_secondary_init(unsigned int cpu) * let the primary processor know we're out of the * pen, then head off into the C entry point */ - write_pen_release(-1); + exynos_write_pen_release(-1); /* * Synchronise with the boot thread. @@ -322,12 +327,12 @@ static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle) /* * The secondary processor is waiting to be released from * the holding pen - release it, then wait for it to flag - * that it has been released by resetting pen_release. + * that it has been released by resetting exynos_pen_release. * - * Note that "pen_release" is the hardware CPU core ID, whereas + * Note that "exynos_pen_release" is the hardware CPU core ID, whereas * "cpu" is Linux's internal ID. */ - write_pen_release(core_id); + exynos_write_pen_release(core_id); if (!exynos_cpu_power_state(core_id)) { exynos_cpu_power_up(core_id); @@ -376,13 +381,13 @@ static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle) else arch_send_wakeup_ipi_mask(cpumask_of(cpu)); - if (pen_release == -1) + if (exynos_pen_release == -1) break; udelay(10); } - if (pen_release != -1) + if (exynos_pen_release != -1) ret = -ETIMEDOUT; /* @@ -392,7 +397,7 @@ static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle) fail: spin_unlock(&boot_lock); - return pen_release != -1 ? ret : 0; + return exynos_pen_release != -1 ? ret : 0; } static void __init exynos_smp_prepare_cpus(unsigned int max_cpus) diff --git a/arch/arm/mach-prima2/common.h b/arch/arm/mach-prima2/common.h index 6d77b622d168..457eb7b18160 100644 --- a/arch/arm/mach-prima2/common.h +++ b/arch/arm/mach-prima2/common.h @@ -15,6 +15,8 @@ #include #include +extern volatile int prima2_pen_release; + extern const struct smp_operations sirfsoc_smp_ops; extern void sirfsoc_secondary_startup(void); extern void sirfsoc_cpu_die(unsigned int cpu); diff --git a/arch/arm/mach-prima2/headsmp.S b/arch/arm/mach-prima2/headsmp.S index 209d9fc5c16c..6cf4fc60347b 100644 --- a/arch/arm/mach-prima2/headsmp.S +++ b/arch/arm/mach-prima2/headsmp.S @@ -34,4 +34,4 @@ ENDPROC(sirfsoc_secondary_startup) .align 1: .long . - .long pen_release + .long prima2_pen_release diff --git a/arch/arm/mach-prima2/hotplug.c b/arch/arm/mach-prima2/hotplug.c index a728c78b996f..b6cf1527e330 100644 --- a/arch/arm/mach-prima2/hotplug.c +++ b/arch/arm/mach-prima2/hotplug.c @@ -11,6 +11,7 @@ #include #include +#include "common.h" static inline void platform_do_lowpower(unsigned int cpu) { @@ -18,7 +19,7 @@ static inline void platform_do_lowpower(unsigned int cpu) for (;;) { __asm__ __volatile__("dsb\n\t" "wfi\n\t" : : : "memory"); - if (pen_release == cpu_logical_map(cpu)) { + if (prima2_pen_release == cpu_logical_map(cpu)) { /* * OK, proper wakeup, we're done */ diff --git a/arch/arm/mach-prima2/platsmp.c b/arch/arm/mach-prima2/platsmp.c index 75ef5d4be554..d1f8b5168083 100644 --- a/arch/arm/mach-prima2/platsmp.c +++ b/arch/arm/mach-prima2/platsmp.c @@ -24,13 +24,16 @@ static void __iomem *clk_base; static DEFINE_SPINLOCK(boot_lock); +/* XXX prima2_pen_release is cargo culted code - DO NOT COPY XXX */ +volatile int prima2_pen_release = -1; + static void sirfsoc_secondary_init(unsigned int cpu) { /* * let the primary processor know we're out of the * pen, then head off into the C entry point */ - pen_release = -1; + prima2_pen_release = -1; smp_wmb(); /* @@ -80,13 +83,13 @@ static int sirfsoc_boot_secondary(unsigned int cpu, struct task_struct *idle) /* * The secondary processor is waiting to be released from * the holding pen - release it, then wait for it to flag - * that it has been released by resetting pen_release. + * that it has been released by resetting prima2_pen_release. * - * Note that "pen_release" is the hardware CPU ID, whereas + * Note that "prima2_pen_release" is the hardware CPU ID, whereas * "cpu" is Linux's internal ID. */ - pen_release = cpu_logical_map(cpu); - sync_cache_w(&pen_release); + prima2_pen_release = cpu_logical_map(cpu); + sync_cache_w(&prima2_pen_release); /* * Send the secondary CPU SEV, thereby causing the boot monitor to read @@ -97,7 +100,7 @@ static int sirfsoc_boot_secondary(unsigned int cpu, struct task_struct *idle) timeout = jiffies + (1 * HZ); while (time_before(jiffies, timeout)) { smp_rmb(); - if (pen_release == -1) + if (prima2_pen_release == -1) break; udelay(10); @@ -109,7 +112,7 @@ static int sirfsoc_boot_secondary(unsigned int cpu, struct task_struct *idle) */ spin_unlock(&boot_lock); - return pen_release != -1 ? -ENOSYS : 0; + return prima2_pen_release != -1 ? -ENOSYS : 0; } const struct smp_operations sirfsoc_smp_ops __initconst = { diff --git a/arch/arm/mach-spear/generic.h b/arch/arm/mach-spear/generic.h index 909b97c0b237..815333fc320c 100644 --- a/arch/arm/mach-spear/generic.h +++ b/arch/arm/mach-spear/generic.h @@ -20,6 +20,8 @@ #include +extern volatile int prima2_pen_release; + extern void spear13xx_timer_init(void); extern void spear3xx_timer_init(void); extern struct pl022_ssp_controller pl022_plat_data; diff --git a/arch/arm/mach-spear/headsmp.S b/arch/arm/mach-spear/headsmp.S index c52192dc3d9f..6e250b6c0aa2 100644 --- a/arch/arm/mach-spear/headsmp.S +++ b/arch/arm/mach-spear/headsmp.S @@ -43,5 +43,5 @@ pen: ldr r7, [r6] .align 1: .long . - .long pen_release + .long spear_pen_release ENDPROC(spear13xx_secondary_startup) diff --git a/arch/arm/mach-spear/hotplug.c b/arch/arm/mach-spear/hotplug.c index 12edd1cf8a12..0dd84f609627 100644 --- a/arch/arm/mach-spear/hotplug.c +++ b/arch/arm/mach-spear/hotplug.c @@ -16,6 +16,8 @@ #include #include +#include "generic.h" + static inline void cpu_enter_lowpower(void) { unsigned int v; @@ -57,7 +59,7 @@ static inline void spear13xx_do_lowpower(unsigned int cpu, int *spurious) for (;;) { wfi(); - if (pen_release == cpu) { + if (spear_pen_release == cpu) { /* * OK, proper wakeup, we're done */ diff --git a/arch/arm/mach-spear/platsmp.c b/arch/arm/mach-spear/platsmp.c index 39038a03836a..b1ff4bb86f6d 100644 --- a/arch/arm/mach-spear/platsmp.c +++ b/arch/arm/mach-spear/platsmp.c @@ -20,16 +20,21 @@ #include #include "generic.h" +/* XXX spear_pen_release is cargo culted code - DO NOT COPY XXX */ +volatile int spear_pen_release = -1; + /* - * Write pen_release in a way that is guaranteed to be visible to all - * observers, irrespective of whether they're taking part in coherency + * XXX CARGO CULTED CODE - DO NOT COPY XXX + * + * Write spear_pen_release in a way that is guaranteed to be visible to + * all observers, irrespective of whether they're taking part in coherency * or not. This is necessary for the hotplug code to work reliably. */ -static void write_pen_release(int val) +static void spear_write_pen_release(int val) { - pen_release = val; + spear_pen_release = val; smp_wmb(); - sync_cache_w(&pen_release); + sync_cache_w(&spear_pen_release); } static DEFINE_SPINLOCK(boot_lock); @@ -42,7 +47,7 @@ static void spear13xx_secondary_init(unsigned int cpu) * let the primary processor know we're out of the * pen, then head off into the C entry point */ - write_pen_release(-1); + spear_write_pen_release(-1); /* * Synchronise with the boot thread. @@ -64,17 +69,17 @@ static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle) /* * The secondary processor is waiting to be released from * the holding pen - release it, then wait for it to flag - * that it has been released by resetting pen_release. + * that it has been released by resetting spear_pen_release. * - * Note that "pen_release" is the hardware CPU ID, whereas + * Note that "spear_pen_release" is the hardware CPU ID, whereas * "cpu" is Linux's internal ID. */ - write_pen_release(cpu); + spear_write_pen_release(cpu); timeout = jiffies + (1 * HZ); while (time_before(jiffies, timeout)) { smp_rmb(); - if (pen_release == -1) + if (spear_pen_release == -1) break; udelay(10); @@ -86,7 +91,7 @@ static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle) */ spin_unlock(&boot_lock); - return pen_release != -1 ? -ENOSYS : 0; + return spear_pen_release != -1 ? -ENOSYS : 0; } /*