From patchwork Mon Oct 19 18:23:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bjorn Andersson X-Patchwork-Id: 284995 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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, 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 12571C433E7 for ; Mon, 19 Oct 2020 18:22:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CB65A223FD for ; Mon, 19 Oct 2020 18:22:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="YrXdztVk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730723AbgJSSWt (ORCPT ); Mon, 19 Oct 2020 14:22:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50226 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730654AbgJSSWs (ORCPT ); Mon, 19 Oct 2020 14:22:48 -0400 Received: from mail-oi1-x242.google.com (mail-oi1-x242.google.com [IPv6:2607:f8b0:4864:20::242]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B6BD0C0613CE for ; Mon, 19 Oct 2020 11:22:48 -0700 (PDT) Received: by mail-oi1-x242.google.com with SMTP id l85so931468oih.10 for ; Mon, 19 Oct 2020 11:22:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=3LEDkBR8wJEGqVwvG1n0vRZnt/gLCojl7HrdvEA23Ug=; b=YrXdztVk2xUzJpFj9keaplNRccfTfjsSp/1YpeMFBVOGa098MtUAjHt61JjJfsvx/w 7EKLabdjT74UjcZyARJs/+dEFCBrXaKQUCXVdXINEZn74DjZFX9xZpHprPKxlyFl4v7q 1IXwJueTvIPnVUUy5jqry7hlVBoPJstOWFATwNXXfQfByZWagKZZAej5cizJzQP0llFM cVHzvgqxTsGL3FeHLVjhsIybaxWtM6L8hPG5pnNywmmUeiEieclplkHhmKrxZGxFkFnh obpbsliy1aQ0//16iq5tEFV3B3LLNNHnDcGgNnXATsxulFTVxLPxNIkr7OJSSHCcd6uS UJog== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=3LEDkBR8wJEGqVwvG1n0vRZnt/gLCojl7HrdvEA23Ug=; b=cbqR1aufDGFGQ5reaX2MDFpHjUalya5Dcx3ivzAtmzdPe8+eN1qIO5r0Q/JVOk2Y0/ asdaikPOCpMzN2eCCfBj6A/MQB+iWa6AcmWDMdLaz8Vr/psEiKqTAjhw6vmbYdY3TT4w eDY2div9WYVd8oggeHJ9Q5NXmcyHnwqVKWmuBAsGAAXIGJ93+5CqxsBOVB+BvT0pG4Ql V2ky2pa5CKayk7zHqRFZ5aH1D6V+a8+NgcYztom6RxNa9AKIo4Qtlp6uNV0fnh7cSeLp AhOLZ1RmGihWzVv0BDYWeaEQW2ZoHxk7bobuUxKN02wkpJGGh4AuPRHoNJobgXhiMjSK GNlw== X-Gm-Message-State: AOAM531oWO6N7JYA1c+qczyOhIHm/Q1jXL/u2eTkFQcnzaUCXJ3wl7/m bHatQPxX2MWjT6UN5GSz6vJa1w== X-Google-Smtp-Source: ABdhPJz2Xt6yCi4zpBwEAH7Rya8QNBfEhDx9AF+q00be7ONZJMUUj3jtzUAoihEPhpft+Di3dh/oKQ== X-Received: by 2002:aca:b5c6:: with SMTP id e189mr495877oif.47.1603131768050; Mon, 19 Oct 2020 11:22:48 -0700 (PDT) Received: from localhost.localdomain (104-57-184-186.lightspeed.austtx.sbcglobal.net. [104.57.184.186]) by smtp.gmail.com with ESMTPSA id o8sm175296oog.47.2020.10.19.11.22.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 19 Oct 2020 11:22:47 -0700 (PDT) From: Bjorn Andersson To: Will Deacon , Robin Murphy , Joerg Roedel , Sai Prakash Ranjan , Jordan Crouse , Thierry Reding , Rob Clark Cc: linux-arm-kernel@lists.infradead.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org Subject: [PATCH v5 3/3] iommu/arm-smmu-qcom: Implement S2CR quirk Date: Mon, 19 Oct 2020 11:23:23 -0700 Message-Id: <20201019182323.3162386-4-bjorn.andersson@linaro.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201019182323.3162386-1-bjorn.andersson@linaro.org> References: <20201019182323.3162386-1-bjorn.andersson@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org The firmware found in some Qualcomm platforms intercepts writes to S2CR in order to replace bypass type streams with fault; and ignore S2CR updates of type fault. Detect this behavior and implement a custom write_s2cr function in order to trick the firmware into supporting bypass streams by the means of configuring the stream for translation using a reserved and disabled context bank. Also circumvent the problem of configuring faulting streams by configuring the stream as bypass. Signed-off-by: Bjorn Andersson Acked-by: Robin Murphy --- Changes since v4: - Made the bypass_cbndx an integer... - Separated out the "quirk enabled or not" into a bool, rather than reusing (the valid) context bank 0 to represent this. - Dropped the unused EXIDS handling. drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 67 ++++++++++++++++++++++ 1 file changed, 67 insertions(+) diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c index 48627fcf6bed..66ba4870659f 100644 --- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c +++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c @@ -10,8 +10,15 @@ struct qcom_smmu { struct arm_smmu_device smmu; + bool bypass_quirk; + u8 bypass_cbndx; }; +static struct qcom_smmu *to_qcom_smmu(struct arm_smmu_device *smmu) +{ + return container_of(smmu, struct qcom_smmu, smmu); +} + static const struct of_device_id qcom_smmu_client_of_match[] __maybe_unused = { { .compatible = "qcom,adreno" }, { .compatible = "qcom,mdp4" }, @@ -25,9 +32,33 @@ static const struct of_device_id qcom_smmu_client_of_match[] __maybe_unused = { static int qcom_smmu_cfg_probe(struct arm_smmu_device *smmu) { + unsigned int last_s2cr = ARM_SMMU_GR0_S2CR(smmu->num_mapping_groups - 1); + struct qcom_smmu *qsmmu = to_qcom_smmu(smmu); + u32 reg; u32 smr; int i; + /* + * With some firmware versions writes to S2CR of type FAULT are + * ignored, and writing BYPASS will end up written as FAULT in the + * register. Perform a write to S2CR to detect if this is the case and + * if so reserve a context bank to emulate bypass streams. + */ + reg = FIELD_PREP(ARM_SMMU_S2CR_TYPE, S2CR_TYPE_BYPASS) | + FIELD_PREP(ARM_SMMU_S2CR_CBNDX, 0xff) | + FIELD_PREP(ARM_SMMU_S2CR_PRIVCFG, S2CR_PRIVCFG_DEFAULT); + arm_smmu_gr0_write(smmu, last_s2cr, reg); + reg = arm_smmu_gr0_read(smmu, last_s2cr); + if (FIELD_GET(ARM_SMMU_S2CR_TYPE, reg) != S2CR_TYPE_BYPASS) { + qsmmu->bypass_quirk = true; + qsmmu->bypass_cbndx = smmu->num_context_banks - 1; + + set_bit(qsmmu->bypass_cbndx, smmu->context_map); + + reg = FIELD_PREP(ARM_SMMU_CBAR_TYPE, CBAR_TYPE_S1_TRANS_S2_BYPASS); + arm_smmu_gr1_write(smmu, ARM_SMMU_GR1_CBAR(qsmmu->bypass_cbndx), reg); + } + for (i = 0; i < smmu->num_mapping_groups; i++) { smr = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_SMR(i)); @@ -45,6 +76,41 @@ static int qcom_smmu_cfg_probe(struct arm_smmu_device *smmu) return 0; } +static void qcom_smmu_write_s2cr(struct arm_smmu_device *smmu, int idx) +{ + struct arm_smmu_s2cr *s2cr = smmu->s2crs + idx; + struct qcom_smmu *qsmmu = to_qcom_smmu(smmu); + u32 cbndx = s2cr->cbndx; + u32 type = s2cr->type; + u32 reg; + + if (qsmmu->bypass_quirk) { + if (type == S2CR_TYPE_BYPASS) { + /* + * Firmware with quirky S2CR handling will substitute + * BYPASS writes with FAULT, so point the stream to the + * reserved context bank and ask for translation on the + * stream + */ + type = S2CR_TYPE_TRANS; + cbndx = qsmmu->bypass_cbndx; + } else if (type == S2CR_TYPE_FAULT) { + /* + * Firmware with quirky S2CR handling will ignore FAULT + * writes, so trick it to write FAULT by asking for a + * BYPASS. + */ + type = S2CR_TYPE_BYPASS; + cbndx = 0xff; + } + } + + reg = FIELD_PREP(ARM_SMMU_S2CR_TYPE, type) | + FIELD_PREP(ARM_SMMU_S2CR_CBNDX, cbndx) | + FIELD_PREP(ARM_SMMU_S2CR_PRIVCFG, s2cr->privcfg); + arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_S2CR(idx), reg); +} + static int qcom_smmu_def_domain_type(struct device *dev) { const struct of_device_id *match = @@ -86,6 +152,7 @@ static const struct arm_smmu_impl qcom_smmu_impl = { .cfg_probe = qcom_smmu_cfg_probe, .def_domain_type = qcom_smmu_def_domain_type, .reset = qcom_smmu500_reset, + .write_s2cr = qcom_smmu_write_s2cr, }; struct arm_smmu_device *qcom_smmu_impl_init(struct arm_smmu_device *smmu)