From patchwork Fri Jan 10 15:25:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Robin Murphy X-Patchwork-Id: 11327667 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 23AA6138C for ; Fri, 10 Jan 2020 15:26:15 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id F241C2077C for ; Fri, 10 Jan 2020 15:26:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="EkKYp5GF" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F241C2077C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:To :From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=4OmrAFiZDZV3Q3b0KT1rhDND6x5L31eoHjNQXZJ/VbM=; b=EkKYp5GFN0M0c9 RRqvBx3z72eNa7cKlPQrIgg95ePhRr00OwIx6VVuRF4OYxPMl59zobxLH7sRBuKuXz2gw42f1fCFa 6nlT8swOxjXJ0dInNB6ApaSFE36VGd2AkHgReaj8wNzPKUdDkDOyrcU8cOrq6Z40wzoHjrnq/vSM9 A9UTP9v3XUuXy2oArLxpqS5M7babJSFY9TJD+y36S92UEchp8jRpReELws8T44oPqrfoIyp6b5BgQ uwolh2k1jDnItMMJ+H9fH/tiorjv5SGAe0uEUMB8bFlLSlw+h29uynNwEPD4DPJqJN3lFlyhCxA0R 2Dfcg5MY0WdvewRc07iw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1ipwAu-0000XT-8O; Fri, 10 Jan 2020 15:26:12 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1ipwAr-0000Wq-4t for linux-arm-kernel@lists.infradead.org; Fri, 10 Jan 2020 15:26:10 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 81E8D30E; Fri, 10 Jan 2020 07:26:08 -0800 (PST) Received: from e121345-lin.cambridge.arm.com (e121345-lin.cambridge.arm.com [10.1.196.37]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id E99363F6C4; Fri, 10 Jan 2020 07:26:07 -0800 (PST) From: Robin Murphy To: will@kernel.org Subject: [PATCH] iommu/arm-smmu: Improve SMR mask test Date: Fri, 10 Jan 2020 15:25:02 +0000 Message-Id: <2e0f837b38671a322d33a18b7447b95ac2fba796.1578669732.git.robin.murphy@arm.com> X-Mailer: git-send-email 2.23.0.dirty MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200110_072609_231920_20B9E189 X-CRM114-Status: GOOD ( 14.22 ) X-Spam-Score: 0.0 (/) X-Spam-Report: SpamAssassin version 3.4.2 on bombadil.infradead.org summary: Content analysis details: (0.0 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at https://www.dnswl.org/, no trust [217.140.110.172 listed in list.dnswl.org] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Make the SMR mask test more robust against SMR0 being live at probe time, which might happen once we start supporting firmware reservations for framebuffers and suchlike. Signed-off-by: Robin Murphy --- drivers/iommu/arm-smmu.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-) diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index 4f1a350d9529..df6490bc7700 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -946,23 +946,36 @@ static void arm_smmu_write_sme(struct arm_smmu_device *smmu, int idx) static void arm_smmu_test_smr_masks(struct arm_smmu_device *smmu) { u32 smr; + int i; if (!smmu->smrs) return; - + /* + * If we've had to accommodate firmware memory regions, we may + * have live SMRs by now; tread carefully... + * + * Somewhat perversely, not having a free SMR for this test implies we + * can get away without it anyway, as we'll only be able to 'allocate' + * these SMRs for the ID/mask values we're already trusting to be OK. + */ + for (i = 0; i < smmu->num_mapping_groups; i++) + if (!smmu->smrs[i].valid) + goto smr_ok; + return; +smr_ok: /* * SMR.ID bits may not be preserved if the corresponding MASK * bits are set, so check each one separately. We can reject * masters later if they try to claim IDs outside these masks. */ smr = FIELD_PREP(SMR_ID, smmu->streamid_mask); - arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_SMR(0), smr); - smr = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_SMR(0)); + arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_SMR(i), smr); + smr = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_SMR(i)); smmu->streamid_mask = FIELD_GET(SMR_ID, smr); smr = FIELD_PREP(SMR_MASK, smmu->streamid_mask); - arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_SMR(0), smr); - smr = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_SMR(0)); + arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_SMR(i), smr); + smr = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_SMR(i)); smmu->smr_mask_mask = FIELD_GET(SMR_MASK, smr); }