From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8D8C6C2F42E for ; Mon, 21 Jan 2019 15:34:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 66B0F2085A for ; Mon, 21 Jan 2019 15:34:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730142AbfAUPeY (ORCPT ); Mon, 21 Jan 2019 10:34:24 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:36480 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730103AbfAUPeW (ORCPT ); Mon, 21 Jan 2019 10:34:22 -0500 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 239A6EBD; Mon, 21 Jan 2019 07:34:22 -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 2AE363F5C1; Mon, 21 Jan 2019 07:34:20 -0800 (PST) From: Julien Thierry To: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, daniel.thompson@linaro.org, joel@joelfernandes.org, marc.zyngier@arm.com, christoffer.dall@arm.com, james.morse@arm.com, catalin.marinas@arm.com, will.deacon@arm.com, mark.rutland@arm.com, Julien Thierry Subject: [PATCH v9 09/26] arm64: Unmask PMR before going idle Date: Mon, 21 Jan 2019 15:33:28 +0000 Message-Id: <1548084825-8803-10-git-send-email-julien.thierry@arm.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1548084825-8803-1-git-send-email-julien.thierry@arm.com> References: <1548084825-8803-1-git-send-email-julien.thierry@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 -- 1.9.1