From patchwork Wed Dec 12 16:47:25 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julien Thierry X-Patchwork-Id: 10726771 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 3FC2F91E for ; Wed, 12 Dec 2018 16:53:08 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2DA9C2B830 for ; Wed, 12 Dec 2018 16:53:08 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 21DB72B836; Wed, 12 Dec 2018 16:53:08 +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 0C7582B830 for ; Wed, 12 Dec 2018 16:53:07 +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=xXiSBAPqFkPlQRRxz1Lf7h5uYTJyrFTUdagN+d8LE7I=; b=XnwBqCkJtpYiS1chEl/29eg0m1 EsIEZfTWpFBaiRWoC35Gu4umsDdWWpUefR4yNmVar5IxcP44Hu+xBiWA9HcfmczVcLrUUdleznvWK +3Z/Z/HPrkNggixdBI8w8W0U1g8AEWpuAIT/IPfyko7yRW1aeS7AwnGwUfO9wPlJKjsHG5Ptdk0KZ EHjca/SaEOEAEwwrV/+7SlRaKxlMz50VWVI86yot2soPNyzsP6Ko41kxw0m1LG4XqNZKxh0eKg4VK gexqWxCpWD62WUXVhQge1+uIZAL3eWAL1X9PgeVjPyp6bNjysq+UlOnoRtKaNNv1FQWPrhUkqRL0u Ls45zg8w==; 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 1gX7kt-0008Sz-Rz; Wed, 12 Dec 2018 16:53:03 +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 1gX7gk-0002hO-MO for linux-arm-kernel@lists.infradead.org; Wed, 12 Dec 2018 16:49:02 +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 9F9AF15BF; Wed, 12 Dec 2018 08:48:46 -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 A69DD3F575; Wed, 12 Dec 2018 08:48:44 -0800 (PST) From: Julien Thierry To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v7 25/25] arm64: Enable the support of pseudo-NMIs Date: Wed, 12 Dec 2018 16:47:25 +0000 Message-Id: <1544633245-6036-26-git-send-email-julien.thierry@arm.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1544633245-6036-1-git-send-email-julien.thierry@arm.com> References: <1544633245-6036-1-git-send-email-julien.thierry@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181212_084847_628435_70068A50 X-CRM114-Status: GOOD ( 16.40 ) 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 Add a build option and a command line parameter to build and enable the support of pseudo-NMIs. Signed-off-by: Julien Thierry Suggested-by: Daniel Thompson Cc: Catalin Marinas Cc: Will Deacon --- Documentation/admin-guide/kernel-parameters.txt | 6 ++++++ arch/arm64/Kconfig | 14 ++++++++++++++ arch/arm64/kernel/cpufeature.c | 11 ++++++++++- 3 files changed, 30 insertions(+), 1 deletion(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index aefd358..0e6628d 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1184,6 +1184,12 @@ to discrete, to make X server driver able to add WB entry later. This parameter enables that. + enable_pseudo_nmi [ARM64] + Enables support for pseudo-NMIs in the kernel. This + requires both the kernel to be built with + CONFIG_ARM64_PSEUDO_NMI and to be running on a + platform with GICv3. + enable_timer_pin_1 [X86] Enable PIN 1 of APIC timer Can be useful to work around chipset bugs diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index ea2ab03..3c294f6 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -983,6 +983,20 @@ config ARM64_SSBD If unsure, say Y. +config ARM64_PSEUDO_NMI + bool "Support for NMI-like interrupts" + select CONFIG_ARM_GIC_V3 + help + Adds support for mimicking Non-Maskable Interrupts through the use of + GIC interrupt priority. This support requires version 3 or later of + Arm GIC. + + This high priority configuration for interrupts need to be + explicitly enabled through the new kernel parameter + "enable_pseudo_nmi". + + If unsure, say N + menuconfig ARMV8_DEPRECATED bool "Emulate deprecated/obsolete ARMv8 instructions" depends on COMPAT diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index b78205a..7f03f0b 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -1149,10 +1149,19 @@ static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused) #endif /* CONFIG_ARM64_RAS_EXTN */ #ifdef CONFIG_ARM64_PSEUDO_NMI +static bool enable_pseudo_nmi; + +static int __init early_enable_pseudo_nmi(char *p) +{ + enable_pseudo_nmi = true; + return 0; +} +early_param("enable_pseudo_nmi", early_enable_pseudo_nmi); + static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry, int scope) { - return false; + return enable_pseudo_nmi && has_useable_gicv3_cpuif(entry, scope); } #endif