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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A4CEEC88E50 for ; Mon, 14 Sep 2026 10:22:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=yxdNpcGulDPHptxAYTQ3/RA2+jf6IzOaeSaGvumBXnc=; b=C+m7ug2b6IrJw2mTYYQyi0bC+T /xPONMqDMA8h3/X0KDlSlUqd+1W2bsWkfVMQpyHWOXTtI4QOTY0GVAglTgvKThloEwYi9DVkORC2I DD89+qwi1YtUgck5+TJsuADIwyZ4JykhT9YTF4mAC1k5kkGg36rPM7GqeqH9dUhryumOUta5N0yzA k0fC1uUtSL9uk7d6FKZpJpV2Zu4AwlifUl/gm01ew2w2/QNZVRkbDp0bbemw+ED5XMqWlq+snrAEQ p9vTOUqYQU9T3fW2F3TTyz7yshAgcMEa0q2XsRncweCHwIggIVHe/sTBC5j2aSaa6SEDm0JSdQdsR HCiR7KRg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x63pU-00000003682-0G5s; Mon, 14 Sep 2026 10:22:28 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x63ow-000000035VZ-0Gic for linux-arm-kernel@lists.infradead.org; Mon, 14 Sep 2026 10:21:55 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 172FA1CC4; Mon, 14 Sep 2026 03:21:50 -0700 (PDT) Received: from login2.euhpc2.arm.com (login2.euhpc2.arm.com [10.58.100.22]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 8D31A3F7B4; Mon, 14 Sep 2026 03:21:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1789381313; bh=Q+anWvz4MhVvNjRofJ78HmqKTzubKdFr4fyy/6NF4QU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MCXhq8Rm1cpNTONZQngHiTL3RmxWBWy2QwRqrL/JmAFiI8ApHZ17ZW46+xuCMV88y vcCoaXGXsRfSeuOXOdWBLYReF8VwDPw6vsOU6BlL9MuYCGyXcU7yASTlVMdzypxDGK if2WMOgcPdxTcq5jPkMSmt+buJ8NM90AWRA+FNUI= From: Vladimir Murzin To: linux-arm-kernel@lists.infradead.org Cc: catalin.marinas@arm.com, will@kernel.org, mark.rutland@arm.com, maz@kernel.org, lpieralisi@kernel.org, ruanjinjie@huawei.com, liaochang1@huawei.com Subject: [PATCH 18/38] arm64: booting: Document boot requirements for FEAT_NMI Date: Mon, 14 Sep 2026 11:20:42 +0100 Message-Id: <20260914102102.68597-19-vladimir.murzin@arm.com> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20260914102102.68597-1-vladimir.murzin@arm.com> References: <20260914102102.68597-1-vladimir.murzin@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260914_032154_151023_4D31A5EF X-CRM114-Status: UNSURE ( 9.84 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Mark Brown In order to use FEAT_NMI we must be able to use ALLINT, require that it behave as though not trapped when it is present. Signed-off-by: Mark Brown Signed-off-by: Ada Couprie Diaz Signed-off-by: Vladimir Murzin Reviewed-by: Jinjie Ruan --- Documentation/arch/arm64/booting.rst | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/Documentation/arch/arm64/booting.rst b/Documentation/arch/arm64/booting.rst index 13ef311dace8..3170b26ae981 100644 --- a/Documentation/arch/arm64/booting.rst +++ b/Documentation/arch/arm64/booting.rst @@ -568,6 +568,12 @@ Before jumping into the kernel, the following conditions must be met: - HCRX_EL2.EnASR (bit 2) must be initialised to 0b1. + For CPUs with support for Non-maskable Interrupts (FEAT_NMI): + + - If the kernel is entered at EL1 and EL2 is present: + + - HCRX_EL2.TALLINT (bit 6) must be initialised to 0b0. + The requirements described above for CPU mode, caches, MMUs, architected timers, coherency and system registers apply to all CPUs. All CPUs must enter the kernel in the same exception level. Where the values documented -- 2.34.1