From patchwork Tue Jan 8 14:07:27 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julien Thierry X-Patchwork-Id: 10752111 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 0E0D891E for ; Tue, 8 Jan 2019 14:12:16 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EF85128BE9 for ; Tue, 8 Jan 2019 14:12:15 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E3DD628C45; Tue, 8 Jan 2019 14:12:15 +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 7743328BE9 for ; Tue, 8 Jan 2019 14:12:15 +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:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=uinbAFEMOi3o0AcmNeNhFyboBuQiW6ZSNpNq2gdqrLA=; b=H9uRCE+jklkTuvYsQzWVCvrUyV N2/+imGb5PLhqrrL0ebjMPSbAT3k1Qtrjbp4jnypA2FIXNLg5uB/1JO5zCrSn62Upyee7nMEqYNuc qPXlin7LfXy2UJOr4Ou2vVDLFo9sTKbR7kaHbT2t3jKHkOfMYftq5oj1lLD+LM3BhEdbu3TIJ4piw LMpwsXYFjYKMQ7cCXiKatItnH/QS0PhoLZogKZ/LcI2SBYvn4ZTcDNxPGq+tzsEMOYbyxGUOiFUOi u8dI2GmWNpR/psMBjsdStFVzQmoCQl4pHW6lGDeOjoaXB+qZAWpsvLcysZD+oNjKaYM6RIP4e06Ue jdkUhnzg==; 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 1ggs70-0004Qj-18; Tue, 08 Jan 2019 14:12:10 +0000 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70] helo=foss.arm.com) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1ggs3H-0007GO-Ei for linux-arm-kernel@lists.infradead.org; Tue, 08 Jan 2019 14:08:45 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E8421165C; Tue, 8 Jan 2019 06:08:18 -0800 (PST) Received: from e112298-lin.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id EC9AA3F70D; Tue, 8 Jan 2019 06:08:16 -0800 (PST) From: Julien Thierry To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v8 09/26] arm64: Unmask PMR before going idle Date: Tue, 8 Jan 2019 14:07:27 +0000 Message-Id: <1546956464-48825-10-git-send-email-julien.thierry@arm.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1546956464-48825-1-git-send-email-julien.thierry@arm.com> References: <1546956464-48825-1-git-send-email-julien.thierry@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190108_060820_372048_1DAC9167 X-CRM114-Status: GOOD ( 15.70 ) 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: mark.rutland@arm.com, daniel.thompson@linaro.org, Julien Thierry , marc.zyngier@arm.com, catalin.marinas@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, christoffer.dall@arm.com, james.morse@arm.com, joel@joelfernandes.org MIME-Version: 1.0 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 CPU does not received signals for interrupts with a priority masked by ICC_PMR_EL1. This means the CPU might not come back from a WFI instruction. Make sure ICC_PMR_EL1 does not mask interrupts when doing a WFI. Since the logic of cpu_do_idle is becoming a bit more complex than just two instructions, lets turn it from ASM to C. Signed-off-by: Julien Thierry Suggested-by: Daniel Thompson Cc: Catalin Marinas Cc: Will Deacon --- arch/arm64/kernel/process.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ arch/arm64/mm/proc.S | 11 ----------- 2 files changed, 45 insertions(+), 11 deletions(-) diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 6d410fc..f05b63f 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -51,6 +51,7 @@ #include #include +#include #include #include #include @@ -74,6 +75,50 @@ void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd); +static inline void __cpu_do_idle(void) +{ + dsb(sy); + wfi(); +} + +static inline void __cpu_do_idle_irqprio(void) +{ + unsigned long pmr; + unsigned long daif_bits; + + daif_bits = read_sysreg(daif); + write_sysreg(daif_bits | PSR_I_BIT, daif); + + /* + * Unmask PMR before going idle to make sure interrupts can + * be raised. + */ + pmr = gic_read_pmr(); + gic_write_pmr(GIC_PRIO_IRQON); + + __cpu_do_idle(); + + gic_write_pmr(pmr); + write_sysreg(daif_bits, daif); +} + +/* + * cpu_do_idle() + * + * Idle the processor (wait for interrupt). + * + * If the CPU supports priority masking we must do additional work to + * ensure that interrupts are not masked at the PMR (because the core will + * not wake up if we block the wake up signal in the interrupt controller). + */ +void cpu_do_idle(void) +{ + if (system_uses_irq_prio_masking()) + __cpu_do_idle_irqprio(); + else + __cpu_do_idle(); +} + /* * This is our default idle handler. */ diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 73886a5..3ea4f3b 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -55,17 +55,6 @@ #define MAIR(attr, mt) ((attr) << ((mt) * 8)) -/* - * cpu_do_idle() - * - * Idle the processor (wait for interrupt). - */ -ENTRY(cpu_do_idle) - dsb sy // WFI may enter a low-power mode - wfi - ret -ENDPROC(cpu_do_idle) - #ifdef CONFIG_CPU_PM /** * cpu_do_suspend - save CPU registers context