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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 142C1C04FE2 for ; Wed, 2 Aug 2023 17:02:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232040AbjHBRCq (ORCPT ); Wed, 2 Aug 2023 13:02:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58054 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231845AbjHBRCl (ORCPT ); Wed, 2 Aug 2023 13:02:41 -0400 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 0439A1981; Wed, 2 Aug 2023 10:02:40 -0700 (PDT) Received: from rrs24-12-35.corp.microsoft.com (unknown [131.107.147.181]) by linux.microsoft.com (Postfix) with ESMTPSA id 67061238C435; Wed, 2 Aug 2023 10:02:39 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 67061238C435 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1690995759; bh=fDMlaBv0OrmjGT2rCt6r3VpG49OJGOp86FWwQR6AG8I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=L1ieVBZWubgn3K8CtQJ2GToFuRe/5t4o2TI7D68NzJCJa6xo4uOEIsw8WIufxiolD mIRowRETYATxzn99dmI5lxZA7QlvOXkvYvc07MOrIqwV0gM4Ii2+ZyrOmlcLX8N2iL B/RDyfWFHifnKM0VSUXQRhBLrqVRCzsuBz/mehk8= From: Easwar Hariharan To: stable@vger.kernel.org Cc: easwar.hariharan@microsoft.com, Robin Murphy , Nicolin Chen , Will Deacon , Catalin Marinas , Jonathan Corbet , Joerg Roedel , Sasha Levin , Tomas Krcka , Yicong Yang , linux-arm-kernel@lists.infradead.org (moderated list:ARM64 PORT (AARCH64 ARCHITECTURE)), linux-doc@vger.kernel.org (open list:DOCUMENTATION), linux-kernel@vger.kernel.org (open list), iommu@lists.linux-foundation.org (open list:IOMMU DRIVERS), iommu@lists.linux.dev (open list:IOMMU DRIVERS) Subject: [PATCH v3 5.15 3/6] iommu/arm-smmu-v3: Work around MMU-600 erratum 1076982 Date: Wed, 2 Aug 2023 17:02:24 +0000 Message-Id: <20230802170227.1590187-4-eahariha@linux.microsoft.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230802170227.1590187-1-eahariha@linux.microsoft.com> References: <20230802170227.1590187-1-eahariha@linux.microsoft.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org From: Robin Murphy commit f322e8af35c7f23a8c08b595c38d6c855b2d836f upstream MMU-600 versions prior to r1p0 fail to correctly generate a WFE wakeup event when the command queue transitions fom full to non-full. We can easily work around this by simply hiding the SEV capability such that we fall back to polling for space in the queue - since MMU-600 implements MSIs we wouldn't expect to need SEV for sync completion either, so this should have little to no impact. Signed-off-by: Robin Murphy Reviewed-by: Nicolin Chen Tested-by: Nicolin Chen Link: https://lore.kernel.org/r/08adbe3d01024d8382a478325f73b56851f76e49.1683731256.git.robin.murphy@arm.com Signed-off-by: Will Deacon Signed-off-by: Easwar Hariharan --- Documentation/arm64/silicon-errata.rst | 2 ++ drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 29 +++++++++++++++++++++ drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 6 +++++ 3 files changed, 37 insertions(+) diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst index f64354f8a79f..55e1e074dec1 100644 --- a/Documentation/arm64/silicon-errata.rst +++ b/Documentation/arm64/silicon-errata.rst @@ -122,6 +122,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | MMU-500 | #841119,826419 | N/A | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | MMU-600 | #1076982 | N/A | ++----------------+-----------------+-----------------+-----------------------------+ +----------------+-----------------+-----------------+-----------------------------+ | Broadcom | Brahma-B53 | N/A | ARM64_ERRATUM_845719 | +----------------+-----------------+-----------------+-----------------------------+ diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index bcdb2cbdda97..782d040a829c 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -3459,6 +3459,33 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass) return 0; } +#define IIDR_IMPLEMENTER_ARM 0x43b +#define IIDR_PRODUCTID_ARM_MMU_600 0x483 + +static void arm_smmu_device_iidr_probe(struct arm_smmu_device *smmu) +{ + u32 reg; + unsigned int implementer, productid, variant, revision; + + reg = readl_relaxed(smmu->base + ARM_SMMU_IIDR); + implementer = FIELD_GET(IIDR_IMPLEMENTER, reg); + productid = FIELD_GET(IIDR_PRODUCTID, reg); + variant = FIELD_GET(IIDR_VARIANT, reg); + revision = FIELD_GET(IIDR_REVISION, reg); + + switch (implementer) { + case IIDR_IMPLEMENTER_ARM: + switch (productid) { + case IIDR_PRODUCTID_ARM_MMU_600: + /* Arm erratum 1076982 */ + if (variant == 0 && revision <= 2) + smmu->features &= ~ARM_SMMU_FEAT_SEV; + break; + } + break; + } +} + static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu) { u32 reg; @@ -3664,6 +3691,8 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu) smmu->ias = max(smmu->ias, smmu->oas); + arm_smmu_device_iidr_probe(smmu); + if (arm_smmu_sva_supported(smmu)) smmu->features |= ARM_SMMU_FEAT_SVA; diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h index 4cb136f07914..5964e02c4e57 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h @@ -69,6 +69,12 @@ #define IDR5_VAX GENMASK(11, 10) #define IDR5_VAX_52_BIT 1 +#define ARM_SMMU_IIDR 0x18 +#define IIDR_PRODUCTID GENMASK(31, 20) +#define IIDR_VARIANT GENMASK(19, 16) +#define IIDR_REVISION GENMASK(15, 12) +#define IIDR_IMPLEMENTER GENMASK(11, 0) + #define ARM_SMMU_CR0 0x20 #define CR0_ATSCHK (1 << 4) #define CR0_CMDQEN (1 << 3) -- 2.25.1