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 1008BCF5395 for ; Wed, 23 Oct 2024 14:37:25 +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=TKoI9dEllx1TNgC9xZVCozD6BRiFRJgzuEW3oaX71qI=; b=G1jH9Oq3WN2heaWfEtzH2EazzA +nTyL/IAZuZGnKSh3uFMLY7J5/RzZpUBH/UhiYlz8kmv3XIdRVtVFu3Vt4a3EXVpW+Y9UrJTLPFZF 12qTAfoocKhQ/hkG7lttsJ9H0LIqSq0PJmuiSap0ANrKb9o297uOgnWJ9suTHGOBXjcl3HLxv13XJ sHqJhZ584wic+tV+gYGRHcV+Et9yR88GfNCiHy+Noy5vTwgrRYqQsPqoM8/HocfFO0Y0cRjxFzb6R FWi9rdok/KxWCFG1vBwWt7Aa5FoXnMNWgOUlX5pwH/efYKMVOXdV96g+vhk6HY7JJTvHDM0dR0O0l TBfjbz4Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1t3cU6-0000000EkaE-1wt0; Wed, 23 Oct 2024 14:37:14 +0000 Received: from nyc.source.kernel.org ([2604:1380:45d1:ec00::3]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1t3cOa-0000000Ei6U-3V01 for linux-arm-kernel@lists.infradead.org; Wed, 23 Oct 2024 14:31:40 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id BADF3A44F3A; Wed, 23 Oct 2024 14:31:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B0210C4CEC6; Wed, 23 Oct 2024 14:31:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1729693891; bh=DTPT4zl44npMYzjERrEH9EvBCMsinVpzO0mfU1W/K+s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Hb9j67H0cQJisbeOByZnDrvtNRkiL0B/AQ60yQMivg7recmbCI3cpy9hLv7dt0iSr ZHGFcgklUTzkrYEgqtboOWpMpoEAlcATRRXtn6oUMMP8E6NkZOERzQSgkD+mLd9Ufe 2U0VnpexlJDbSgR3+nuxg3s9uTBObiTd8OKuiRWgKfjG2HZ4g8z/RniynOD8EVBrNQ NoYyx5ASofpW2GHYNjpPR8d1ZE+fXCKPVuBsVF/J7uvpg+YaX0T8QSFoVgUmEZAyEH o8Y3tSgBshTjZXLIGPXR+qt5egiR3iyLpBCwa/+tIJlquzC8zgZyboezniA/MUZb0A mjNFmakYW/bWw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Robin Murphy , Will Deacon , Sasha Levin , joro@8bytes.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev Subject: [PATCH AUTOSEL 6.6 09/23] iommu/arm-smmu: Clarify MMU-500 CPRE workaround Date: Wed, 23 Oct 2024 10:30:53 -0400 Message-ID: <20241023143116.2981369-9-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20241023143116.2981369-1-sashal@kernel.org> References: <20241023143116.2981369-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.6.58 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241023_073133_028341_E47A6BF4 X-CRM114-Status: GOOD ( 12.33 ) 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: Robin Murphy [ Upstream commit 0dfe314cdd0d378f96bb9c6bdc05c8120f48606d ] CPRE workarounds are implicated in at least 5 MMU-500 errata, some of which remain unfixed. The comment and warning message have proven to be unhelpfully misleading about this scope, so reword them to get the point across with less risk of going out of date or confusing users. Signed-off-by: Robin Murphy Link: https://lore.kernel.org/r/dfa82171b5248ad7cf1f25592101a6eec36b8c9a.1728400877.git.robin.murphy@arm.com Signed-off-by: Will Deacon Signed-off-by: Sasha Levin --- drivers/iommu/arm/arm-smmu/arm-smmu-impl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c b/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c index 9dc772f2cbb27..99030e6b16e7a 100644 --- a/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c +++ b/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c @@ -130,7 +130,7 @@ int arm_mmu500_reset(struct arm_smmu_device *smmu) /* * Disable MMU-500's not-particularly-beneficial next-page - * prefetcher for the sake of errata #841119 and #826419. + * prefetcher for the sake of at least 5 known errata. */ for (i = 0; i < smmu->num_context_banks; ++i) { reg = arm_smmu_cb_read(smmu, i, ARM_SMMU_CB_ACTLR); @@ -138,7 +138,7 @@ int arm_mmu500_reset(struct arm_smmu_device *smmu) arm_smmu_cb_write(smmu, i, ARM_SMMU_CB_ACTLR, reg); reg = arm_smmu_cb_read(smmu, i, ARM_SMMU_CB_ACTLR); if (reg & ARM_MMU500_ACTLR_CPRE) - dev_warn_once(smmu->dev, "Failed to disable prefetcher [errata #841119 and #826419], check ACR.CACHE_LOCK\n"); + dev_warn_once(smmu->dev, "Failed to disable prefetcher for errata workarounds, check SACR.CACHE_LOCK\n"); } return 0; -- 2.43.0