From patchwork Wed Aug 2 17:09:09 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Easwar Hariharan X-Patchwork-Id: 13338587 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 132BAC04E69 for ; Wed, 2 Aug 2023 17:09:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=oVPOL7xmLLiYkDu5J79IOY28x585ZqJUgOKur0aIGvI=; b=FRhgGRF0mGyGdU iwH/RnxmmyIKekzBIEdXEMDaONppAjuSXLPNp0/z/EyXAA5FxH3tHnlVKkySDvCK6VClWCfpLom5a 9F+6qFkZFznBZjAdg1KfbF7hXzJmedxcb+LzL8Vo6m/haTEg68dCIBTMNeOQp4PO1bCXllC9y1RIu YqbyWRxyFZARAjVdXJnM/Mx/ZhNVimVQM63HPQSIccj6nItzaOXhsFvy/LMYrW0HieYiERFzY2kZ2 iOnX7cFUa0aPbs5KX3yn1R5aOXNdcwMh4jCzDwdylRnJYNGsk+u+cn3uDtXsccqeHbL0U8vKFGV0S cDfH/q9PtEO0bnFdd62w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qRFLh-005SZf-1q; Wed, 02 Aug 2023 17:09:25 +0000 Received: from linux.microsoft.com ([13.77.154.182]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qRFLe-005SWk-0r for linux-arm-kernel@lists.infradead.org; Wed, 02 Aug 2023 17:09:23 +0000 Received: from rrs24-12-35.corp.microsoft.com (unknown [131.107.147.181]) by linux.microsoft.com (Postfix) with ESMTPSA id C1A5F238C44C; Wed, 2 Aug 2023 10:09:21 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com C1A5F238C44C DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1690996161; bh=9icfp4J2zYiz0EBoXxQatexWubjs/pekIkm1O/em9/Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gEByAG54qs5S8piO7LfqOwKed+wnHuX1ilSitmLEcJ8BYl4gGBsSIKMftsZZ6So+c 6xlN+jkIQ3GktoYBEFBmeNwLXz7vgcEdAjlzMe8Yy5o2siniNUvg7zIqAbYY1VWBfE KG+MEmrL+cxfzCbvw54SB+Zdy7+rq4DJIx9gANQ0= 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 v2 6.1 2/4] iommu/arm-smmu-v3: Document MMU-700 erratum 2812531 Date: Wed, 2 Aug 2023 17:09:09 +0000 Message-Id: <20230802170911.1593275-3-eahariha@linux.microsoft.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230802170911.1593275-1-eahariha@linux.microsoft.com> References: <20230802170911.1593275-1-eahariha@linux.microsoft.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230802_100922_356515_49F11FA7 X-CRM114-Status: GOOD ( 20.35 ) 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 commit 309a15cb16bb075da1c99d46fb457db6a1a2669e upstream To work around MMU-700 erratum 2812531 we need to ensure that certain sequences of commands cannot be issued without an intervening sync. In practice this falls out of our current command-batching machinery anyway - each batch only contains a single type of invalidation command, and ends with a sync. The only exception is when a batch is sufficiently large to need issuing across multiple command queue slots, wherein the earlier slots will not contain a sync and thus may in theory interleave with another batch being issued in parallel to create an affected sequence across the slot boundary. Since MMU-700 supports range invalidate commands and thus we will prefer to use them (which also happens to avoid conditions for other errata), I'm not entirely sure it's even possible for a single high-level invalidate call to generate a batch of more than 63 commands, but for the sake of robustness and documentation, wire up an option to enforce that a sync is always inserted for every slot issued. The other aspect is that the relative order of DVM commands cannot be controlled, so DVM cannot be used. Again that is already the status quo, but since we have at least defined ARM_SMMU_FEAT_BTM, we can explicitly disable it for documentation purposes even if it's not wired up anywhere yet. Signed-off-by: Robin Murphy Reviewed-by: Nicolin Chen Link: https://lore.kernel.org/r/330221cdfd0003cd51b6c04e7ff3566741ad8374.1683731256.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 | 12 ++++++++++++ drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 1 + 3 files changed, 15 insertions(+) diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst index 55e1e074dec1..322df8abbc0e 100644 --- a/Documentation/arm64/silicon-errata.rst +++ b/Documentation/arm64/silicon-errata.rst @@ -124,6 +124,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | MMU-600 | #1076982 | N/A | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | MMU-700 | #2812531 | 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 782d040a829c..6a551a48d271 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -897,6 +897,12 @@ static void arm_smmu_cmdq_batch_add(struct arm_smmu_device *smmu, struct arm_smmu_cmdq_batch *cmds, struct arm_smmu_cmdq_ent *cmd) { + if (cmds->num == CMDQ_BATCH_ENTRIES - 1 && + (smmu->options & ARM_SMMU_OPT_CMDQ_FORCE_SYNC)) { + arm_smmu_cmdq_issue_cmdlist(smmu, cmds->cmds, cmds->num, true); + cmds->num = 0; + } + if (cmds->num == CMDQ_BATCH_ENTRIES) { arm_smmu_cmdq_issue_cmdlist(smmu, cmds->cmds, cmds->num, false); cmds->num = 0; @@ -3461,6 +3467,7 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass) #define IIDR_IMPLEMENTER_ARM 0x43b #define IIDR_PRODUCTID_ARM_MMU_600 0x483 +#define IIDR_PRODUCTID_ARM_MMU_700 0x487 static void arm_smmu_device_iidr_probe(struct arm_smmu_device *smmu) { @@ -3481,6 +3488,11 @@ static void arm_smmu_device_iidr_probe(struct arm_smmu_device *smmu) if (variant == 0 && revision <= 2) smmu->features &= ~ARM_SMMU_FEAT_SEV; break; + case IIDR_PRODUCTID_ARM_MMU_700: + /* Arm erratum 2812531 */ + smmu->features &= ~ARM_SMMU_FEAT_BTM; + smmu->options |= ARM_SMMU_OPT_CMDQ_FORCE_SYNC; + break; } break; } 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 5964e02c4e57..abaecdf8d5d2 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h @@ -651,6 +651,7 @@ struct arm_smmu_device { #define ARM_SMMU_OPT_SKIP_PREFETCH (1 << 0) #define ARM_SMMU_OPT_PAGE0_REGS_ONLY (1 << 1) #define ARM_SMMU_OPT_MSIPOLL (1 << 2) +#define ARM_SMMU_OPT_CMDQ_FORCE_SYNC (1 << 3) u32 options; struct arm_smmu_cmdq cmdq;