From patchwork Tue Mar 9 18:19:27 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rahul Singh X-Patchwork-Id: 12126353 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 04C8BC433E0 for ; Tue, 9 Mar 2021 18:22:11 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 AF13A650F5 for ; Tue, 9 Mar 2021 18:22:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AF13A650F5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.95669.180629 (Exim 4.92) (envelope-from ) id 1lJgzb-0000Ud-3X; Tue, 09 Mar 2021 18:22:03 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 95669.180629; Tue, 09 Mar 2021 18:22:03 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lJgza-0000UW-WE; Tue, 09 Mar 2021 18:22:03 +0000 Received: by outflank-mailman (input) for mailman id 95669; Tue, 09 Mar 2021 18:22:01 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lJgzZ-0000UK-65 for xen-devel@lists.xenproject.org; Tue, 09 Mar 2021 18:22:01 +0000 Received: from foss.arm.com (unknown [217.140.110.172]) by us1-rack-iad1.inumbo.com (Halon) with ESMTP id cc954cf3-1bab-4721-a5c4-6f51a19f6ae5; Tue, 09 Mar 2021 18:21:59 +0000 (UTC) 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 1CAD531B; Tue, 9 Mar 2021 10:21:59 -0800 (PST) Received: from e109506.cambridge.arm.com (e109506.cambridge.arm.com [10.1.199.1]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 334BC3F73C; Tue, 9 Mar 2021 10:21:58 -0800 (PST) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: cc954cf3-1bab-4721-a5c4-6f51a19f6ae5 From: Rahul Singh To: xen-devel@lists.xenproject.org Cc: bertrand.marquis@arm.com, rahul.singh@arm.com, Stefano Stabellini , Julien Grall , Volodymyr Babchuk Subject: [PATCH 3/5] xen/arm: smmuv1: Keep track of S2CR state Date: Tue, 9 Mar 2021 18:19:27 +0000 Message-Id: X-Mailer: git-send-email 2.17.1 In-Reply-To: References: In-Reply-To: References: Backport commit 8e8b203eabd8b9e96d02d6339e4abce3e5a7ea4b "iommu/arm-smmu: Keep track of S2CR state" from the Linux kernel. This patch is the preparatory work to fix the stream match conflict when two devices have the same stream-id. Original commit message: Making S2CRs first-class citizens within the driver with a high-level representation of their state offers a neat solution to a few problems: Firstly, the information about which context a device's stream IDs are associated with is already present by necessity in the S2CR. With that state easily accessible we can refer directly to it and obviate the need to track an IOMMU domain in each device's archdata (its earlier purpose of enforcing correct attachment of multi-device groups now being handled by the IOMMU core itself). Secondly, the core API now deprecates explicit domain detach and expects domain attach to move devices smoothly from one domain to another; for SMMUv2, this notion maps directly to simply rewriting the S2CRs assigned to the device. By giving the driver a suitable abstraction of those S2CRs to work with, we can massively reduce the overhead of the current heavy-handed "detach, free resources, reallocate resources, attach" approach. Thirdly, making the software state hardware-shaped and attached to the SMMU instance once again makes suspend/resume of this register group that much simpler to implement in future. Signed-off-by: Rahul Singh --- xen/drivers/passthrough/arm/smmu.c | 150 +++++++++++++++++------------ 1 file changed, 89 insertions(+), 61 deletions(-) diff --git a/xen/drivers/passthrough/arm/smmu.c b/xen/drivers/passthrough/arm/smmu.c index c41e94f836..e1b937bd4b 100644 --- a/xen/drivers/passthrough/arm/smmu.c +++ b/xen/drivers/passthrough/arm/smmu.c @@ -444,9 +444,20 @@ static struct iommu_group *iommu_group_get(struct device *dev) #define S2CR_CBNDX_MASK 0xff #define S2CR_TYPE_SHIFT 16 #define S2CR_TYPE_MASK 0x3 -#define S2CR_TYPE_TRANS (0 << S2CR_TYPE_SHIFT) -#define S2CR_TYPE_BYPASS (1 << S2CR_TYPE_SHIFT) -#define S2CR_TYPE_FAULT (2 << S2CR_TYPE_SHIFT) +enum arm_smmu_s2cr_type { + S2CR_TYPE_TRANS, + S2CR_TYPE_BYPASS, + S2CR_TYPE_FAULT, +}; + +#define S2CR_PRIVCFG_SHIFT 24 +#define S2CR_PRIVCFG_MASK 0x3 +enum arm_smmu_s2cr_privcfg { + S2CR_PRIVCFG_DEFAULT, + S2CR_PRIVCFG_DIPAN, + S2CR_PRIVCFG_UNPRIV, + S2CR_PRIVCFG_PRIV, +}; /* Context bank attribute registers */ #define ARM_SMMU_GR1_CBAR(n) (0x0 + ((n) << 2)) @@ -585,6 +596,16 @@ enum arm_smmu_arch_version { ARM_SMMU_V2, }; +struct arm_smmu_s2cr { + enum arm_smmu_s2cr_type type; + enum arm_smmu_s2cr_privcfg privcfg; + u8 cbndx; +}; + +#define s2cr_init_val (struct arm_smmu_s2cr){ \ + .type = S2CR_TYPE_FAULT \ +} + struct arm_smmu_smr { u16 mask; u16 id; @@ -631,6 +652,7 @@ struct arm_smmu_device { u16 streamid_mask; u16 smr_mask_mask; struct arm_smmu_smr *smrs; + struct arm_smmu_s2cr *s2crs; unsigned long s1_input_size; unsigned long s1_output_size; @@ -1411,6 +1433,23 @@ static void arm_smmu_write_smr(struct arm_smmu_device *smmu, int idx) writel_relaxed(reg, ARM_SMMU_GR0(smmu) + ARM_SMMU_GR0_SMR(idx)); } +static void arm_smmu_write_s2cr(struct arm_smmu_device *smmu, int idx) +{ + struct arm_smmu_s2cr *s2cr = smmu->s2crs + idx; + u32 reg = (s2cr->type & S2CR_TYPE_MASK) << S2CR_TYPE_SHIFT | + (s2cr->cbndx & S2CR_CBNDX_MASK) << S2CR_CBNDX_SHIFT | + (s2cr->privcfg & S2CR_PRIVCFG_MASK) << S2CR_PRIVCFG_SHIFT; + + writel_relaxed(reg, ARM_SMMU_GR0(smmu) + ARM_SMMU_GR0_S2CR(idx)); +} + +static void arm_smmu_write_sme(struct arm_smmu_device *smmu, int idx) +{ + arm_smmu_write_s2cr(smmu, idx); + if (smmu->smrs) + arm_smmu_write_smr(smmu, idx); +} + static int arm_smmu_master_alloc_smes(struct arm_smmu_device *smmu, struct arm_smmu_master_cfg *cfg) { @@ -1461,6 +1500,23 @@ static void arm_smmu_master_free_smes(struct arm_smmu_device *smmu, { int i; + /* + * We *must* clear the S2CR first, because freeing the SMR means + * that it can be re-allocated immediately. + */ + for (i = 0; i < cfg->num_streamids; ++i) { + int idx = cfg->smendx[i]; + + /* An IOMMU group is torn down by the first device to be removed */ + if (idx == INVALID_SMENDX) + return; + + smmu->s2crs[idx] = s2cr_init_val; + arm_smmu_write_s2cr(smmu, idx); + } + /* Sync S2CR updates before touching anything else */ + __iowmb(); + /* Invalidate the SMRs before freeing back to the allocator */ for (i = 0; i < cfg->num_streamids; ++i) { if (smmu->smrs) @@ -1473,51 +1529,30 @@ static void arm_smmu_master_free_smes(struct arm_smmu_device *smmu, static int arm_smmu_domain_add_master(struct arm_smmu_domain *smmu_domain, struct arm_smmu_master_cfg *cfg) { - int i, ret; + int i, ret = 0; struct arm_smmu_device *smmu = smmu_domain->smmu; - void __iomem *gr0_base = ARM_SMMU_GR0(smmu); + struct arm_smmu_s2cr *s2cr = smmu->s2crs; + enum arm_smmu_s2cr_type type = S2CR_TYPE_TRANS; + u8 cbndx = smmu_domain->cfg.cbndx; - /* Devices in an IOMMU group may already be configured */ - ret = arm_smmu_master_alloc_smes(smmu, cfg); + if (cfg->smendx[0] == INVALID_SMENDX) + ret = arm_smmu_master_alloc_smes(smmu, cfg); if (ret) - return ret == -EEXIST ? 0 : ret; - - for (i = 0; i < cfg->num_streamids; ++i) { - u32 idx, s2cr; - - idx = cfg->smendx[i]; - s2cr = S2CR_TYPE_TRANS | - (smmu_domain->cfg.cbndx << S2CR_CBNDX_SHIFT); - writel_relaxed(s2cr, gr0_base + ARM_SMMU_GR0_S2CR(idx)); - } - - return 0; -} - -static void arm_smmu_domain_remove_master(struct arm_smmu_domain *smmu_domain, - struct arm_smmu_master_cfg *cfg) -{ - int i; - struct arm_smmu_device *smmu = smmu_domain->smmu; - void __iomem *gr0_base = ARM_SMMU_GR0(smmu); + return ret; - /* - * We *must* clear the S2CR first, because freeing the SMR means - * that it can be re-allocated immediately. - * Xen: Unlike Linux, any access to non-configured stream will fault. - */ for (i = 0; i < cfg->num_streamids; ++i) { int idx = cfg->smendx[i]; - /* An IOMMU group is torn down by the first device to be removed */ - if (idx == INVALID_SMENDX) - return; + /* Devices in an IOMMU group may already be configured */ + if (type == s2cr[idx].type && cbndx == s2cr[idx].cbndx) + break; - writel_relaxed(S2CR_TYPE_FAULT, - gr0_base + ARM_SMMU_GR0_S2CR(idx)); + s2cr[idx].type = type ; + s2cr[idx].privcfg = S2CR_PRIVCFG_UNPRIV; + s2cr[idx].cbndx = cbndx; + arm_smmu_write_s2cr(smmu, idx); } - - arm_smmu_master_free_smes(smmu, cfg); + return 0; } static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) @@ -1564,24 +1599,17 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) if (!cfg) return -ENODEV; - ret = arm_smmu_domain_add_master(smmu_domain, cfg); - - if (!ret) - dev_iommu_domain(dev) = domain; - return ret; + return arm_smmu_domain_add_master(smmu_domain, cfg); } static void arm_smmu_detach_dev(struct iommu_domain *domain, struct device *dev) { - struct arm_smmu_domain *smmu_domain = domain->priv; - struct arm_smmu_master_cfg *cfg; + struct arm_smmu_device *smmu = find_smmu_for_device(dev); + struct arm_smmu_master_cfg *cfg = find_smmu_master_cfg(dev); - cfg = find_smmu_master_cfg(dev); - if (!cfg) - return; + if (smmu && cfg) + arm_smmu_master_free_smes(smmu, cfg); - dev_iommu_domain(dev) = NULL; - arm_smmu_domain_remove_master(smmu_domain, cfg); } #if 0 /* @@ -2039,16 +2067,8 @@ static void arm_smmu_device_reset(struct arm_smmu_device *smmu) * Reset stream mapping groups: Initial values mark all SMRn as * invalid and all S2CRn as bypass unless overridden. */ - for (i = 0; i < smmu->num_mapping_groups; ++i) { - if (smmu->smrs) - arm_smmu_write_smr(smmu, i); - /* - * Xen: Unlike Linux, any access to a non-configure stream - * will fault by default. - */ - writel_relaxed(S2CR_TYPE_FAULT, - gr0_base + ARM_SMMU_GR0_S2CR(i)); - } + for (i = 0; i < smmu->num_mapping_groups; ++i) + arm_smmu_write_sme(smmu, i); /* Make sure all context banks are disabled and clear CB_FSR */ for (i = 0; i < smmu->num_context_banks; ++i) { @@ -2110,6 +2130,7 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu) unsigned long size; void __iomem *gr0_base = ARM_SMMU_GR0(smmu); u32 id; + int i; dev_notice(smmu->dev, "probing hardware configuration...\n"); dev_notice(smmu->dev, "SMMUv%d with:\n", smmu->version); @@ -2193,6 +2214,13 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu) "\tstream matching with %lu register groups, mask 0x%x", size, smmu->smr_mask_mask); } + /* s2cr->type == 0 means translation, so initialise explicitly */ + smmu->s2crs = kmalloc_array(size, sizeof(*smmu->s2crs), GFP_KERNEL); + if (!smmu->s2crs) + return -ENOMEM; + for (i = 0; i < size; i++) + smmu->s2crs[i] = s2cr_init_val; + smmu->num_mapping_groups = size; /* ID1 */