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=-16.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 405FFC43618 for ; Wed, 12 May 2021 19:57:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0DB4A6142C for ; Wed, 12 May 2021 19:57:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238382AbhELT6v (ORCPT ); Wed, 12 May 2021 15:58:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:60378 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1353345AbhELSLU (ORCPT ); Wed, 12 May 2021 14:11:20 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 54A0A61457; Wed, 12 May 2021 18:06:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1620842767; bh=JXmTuobwAbnhWAc/TeI1sLaB+hU4IUFukikAe6g+w/g=; h=From:To:Cc:Subject:Date:From; b=gLb/XWywxIl2R3te7Agu1VmZMsQ9j5W9zAIX/0K5auRNRpo4DZKRzom8QDX5lgjCf hQpCEbjQb+D6uYYx/cHXGFgRRjbJ+NsG4O9SUmudiueidV4fjE46fealq/F/wa27ms nWtsjmgy6z3QNwV8bCQKSGpXbkqBBQd0bz/P011VIHpV4trX9MBuPGguk1yXxNirvY VVxVG0sce3Z4W1d6cH9P1WByKYU3vyy7p8/f0v3BsA8OpfdtbofDEbczOpiSeo8YC2 ZJx6tPkke+8ERaKwCs5ax23tS0+ED2HMCkxw2zX21bKWdZCFxdzFrGOtfFF+PRvVUB 6insRFSVcQ91w== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Ard Biesheuvel , Nicolas Pitre , Russell King , Sasha Levin , linux-arm-kernel@lists.infradead.org Subject: [PATCH AUTOSEL 4.4 1/4] ARM: 9058/1: cache-v7: refactor v7_invalidate_l1 to avoid clobbering r5/r6 Date: Wed, 12 May 2021 14:06:00 -0400 Message-Id: <20210512180604.666144-1-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ard Biesheuvel [ Upstream commit f9e7a99fb6b86aa6a00e53b34ee6973840e005aa ] The cache invalidation code in v7_invalidate_l1 can be tweaked to re-read the associativity from CCSIDR, and keep the way identifier component in a single register that is assigned in the outer loop. This way, we need 2 registers less. Given that the number of sets is typically much larger than the associativity, rearrange the code so that the outer loop has the fewer number of iterations, ensuring that the re-read of CCSIDR only occurs a handful of times in practice. Fix the whitespace while at it, and update the comment to indicate that this code is no longer a clone of anything else. Acked-by: Nicolas Pitre Signed-off-by: Ard Biesheuvel Signed-off-by: Russell King Signed-off-by: Sasha Levin --- arch/arm/mm/cache-v7.S | 51 +++++++++++++++++++++--------------------- 1 file changed, 25 insertions(+), 26 deletions(-) diff --git a/arch/arm/mm/cache-v7.S b/arch/arm/mm/cache-v7.S index 11d699af30ed..db568be45946 100644 --- a/arch/arm/mm/cache-v7.S +++ b/arch/arm/mm/cache-v7.S @@ -27,41 +27,40 @@ * processor. We fix this by performing an invalidate, rather than a * clean + invalidate, before jumping into the kernel. * - * This function is cloned from arch/arm/mach-tegra/headsmp.S, and needs - * to be called for both secondary cores startup and primary core resume - * procedures. + * This function needs to be called for both secondary cores startup and + * primary core resume procedures. */ ENTRY(v7_invalidate_l1) mov r0, #0 mcr p15, 2, r0, c0, c0, 0 mrc p15, 1, r0, c0, c0, 0 - movw r1, #0x7fff - and r2, r1, r0, lsr #13 + movw r3, #0x3ff + and r3, r3, r0, lsr #3 @ 'Associativity' in CCSIDR[12:3] + clz r1, r3 @ WayShift + mov r2, #1 + mov r3, r3, lsl r1 @ NumWays-1 shifted into bits [31:...] + movs r1, r2, lsl r1 @ #1 shifted left by same amount + moveq r1, #1 @ r1 needs value > 0 even if only 1 way - movw r1, #0x3ff + and r2, r0, #0x7 + add r2, r2, #4 @ SetShift - and r3, r1, r0, lsr #3 @ NumWays - 1 - add r2, r2, #1 @ NumSets +1: movw r4, #0x7fff + and r0, r4, r0, lsr #13 @ 'NumSets' in CCSIDR[27:13] - and r0, r0, #0x7 - add r0, r0, #4 @ SetShift - - clz r1, r3 @ WayShift - add r4, r3, #1 @ NumWays -1: sub r2, r2, #1 @ NumSets-- - mov r3, r4 @ Temp = NumWays -2: subs r3, r3, #1 @ Temp-- - mov r5, r3, lsl r1 - mov r6, r2, lsl r0 - orr r5, r5, r6 @ Reg = (Temp<