From patchwork Fri Jan 7 19:43:33 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nathan Chancellor X-Patchwork-Id: 530671 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C10ADC433EF for ; Fri, 7 Jan 2022 19:44:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233289AbiAGToE (ORCPT ); Fri, 7 Jan 2022 14:44:04 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:54828 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233284AbiAGToE (ORCPT ); Fri, 7 Jan 2022 14:44:04 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 22F92B82766 for ; Fri, 7 Jan 2022 19:44:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CED73C36AF6; Fri, 7 Jan 2022 19:43:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1641584641; bh=pUhhdPd+RzZRxCZiQKKatqdJiYDHPOjal68wgZclLUs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gLcWua10BSWFs1tzn8R0O9LdAEPfjI2J/mCkZIYGMP1etayiU740tg8inPMM/9UAz 83L6chu71gxLPrNskNJHYeddudOhCqOCzkqSHmu/OVLrqaIVT5LIj6CMCb7zpIPvOP h5SFjTQyVPVch6CP0tWVRijt4oqP6IYQVp7MaswmjOVVblRnvxiV6JRHUt6v1M/jJs s5I4x5DvnMq58Va9lS0bWwZ13+meCMgtMnA8IJUuZrwD63jv6eFiklttiS1bEyXttE n5nLhuiM524i0FtNBBazC5hsFCC+24hI5zY4nE2zvmyLHc8oD1Ep8nf0j9WsgAy0WG EHk/jSJooETiQ== From: Nathan Chancellor To: Greg Kroah-Hartman , Sasha Levin , Catalin Marinas , Will Deacon Cc: Mark Rutland , Marc Zyngier , Nick Desaulniers , linux-arm-kernel@lists.infradead.org, stable@vger.kernel.org, llvm@lists.linux.dev Subject: [PATCH RFC 4.9 3/5] arm64: reduce el2_setup branching Date: Fri, 7 Jan 2022 12:43:33 -0700 Message-Id: <20220107194335.3090066-4-nathan@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220107194335.3090066-1-nathan@kernel.org> References: <20220107194335.3090066-1-nathan@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Mark Rutland commit 3ad47d055aa88d9f4189253f5b5c485f4c4626b2 upstream. The early el2_setup code is a little convoluted, with two branches where one would do. This makes the code more painful to read than is necessary. We can remove a branch and simplify the logic by moving the early return in the booted-at-EL1 case earlier in the function. This separates it from all the setup logic that only makes sense for EL2. Acked-by: Marc Zyngier Signed-off-by: Mark Rutland Cc: Will Deacon Signed-off-by: Catalin Marinas Signed-off-by: Nathan Chancellor --- arch/arm64/kernel/head.S | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 387542383662..b15abc6ae4af 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -489,13 +489,8 @@ ENTRY(el2_setup) msr SPsel, #1 // We want to use SP_EL{1,2} mrs x0, CurrentEL cmp x0, #CurrentEL_EL2 - b.ne 1f - mrs x0, sctlr_el2 -CPU_BE( orr x0, x0, #(1 << 25) ) // Set the EE bit for EL2 -CPU_LE( bic x0, x0, #(1 << 25) ) // Clear the EE bit for EL2 - msr sctlr_el2, x0 - b 2f -1: mrs x0, sctlr_el1 + b.eq 1f + mrs x0, sctlr_el1 CPU_BE( orr x0, x0, #(3 << 24) ) // Set the EE and E0E bits for EL1 CPU_LE( bic x0, x0, #(3 << 24) ) // Clear the EE and E0E bits for EL1 msr sctlr_el1, x0 @@ -503,7 +498,11 @@ CPU_LE( bic x0, x0, #(3 << 24) ) // Clear the EE and E0E bits for EL1 isb ret -2: +1: mrs x0, sctlr_el2 +CPU_BE( orr x0, x0, #(1 << 25) ) // Set the EE bit for EL2 +CPU_LE( bic x0, x0, #(1 << 25) ) // Clear the EE bit for EL2 + msr sctlr_el2, x0 + #ifdef CONFIG_ARM64_VHE /* * Check for VHE being present. For the rest of the EL2 setup,