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 X-Spam-Level: X-Spam-Status: No, score=-5.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNWANTED_LANGUAGE_BODY,USER_AGENT_SANE_1 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 BDE75C43603 for ; Wed, 18 Dec 2019 09:59:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 89B3721D7D for ; Wed, 18 Dec 2019 09:59:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="PFfSVW45" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726090AbfLRJ7x (ORCPT ); Wed, 18 Dec 2019 04:59:53 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:27258 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725828AbfLRJ7v (ORCPT ); Wed, 18 Dec 2019 04:59:51 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1576663189; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ZesRJMwRUaXJolh5+YUZ7E8d3EI/LVFGdC+apBPgCCM=; b=PFfSVW45vT6X9iXcDjd9wWRZWjvNYsd5mFoAHv98/qjf0ZrsLcJTUnzNqMbyo1ew/cJWLN tTz1JPeMay1eCVcdk2vYyROUJVAkfvDeUwZ9a3IhGOLsXCCPDGYqpH1FH4EYFV3G0Vyfht B/jutBodo5GNvzcm4XLuBaZ9KQ/54dM= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-57-1eJWCi-XPYe5E3jzQ4hnIg-1; Wed, 18 Dec 2019 04:59:46 -0500 X-MC-Unique: 1eJWCi-XPYe5E3jzQ4hnIg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5B71B2275; Wed, 18 Dec 2019 09:59:43 +0000 (UTC) Received: from [10.36.116.117] (ovpn-116-117.ams2.redhat.com [10.36.116.117]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A4E4C26DC5; Wed, 18 Dec 2019 09:59:38 +0000 (UTC) Subject: Re: [PATCH v3 10/13] iommu/arm-smmu-v3: Add second level of context descriptor table To: Jean-Philippe Brucker , linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-acpi@vger.kernel.org, devicetree@vger.kernel.org, iommu@lists.linux-foundation.org Cc: joro@8bytes.org, robh+dt@kernel.org, mark.rutland@arm.com, lorenzo.pieralisi@arm.com, guohanjun@huawei.com, sudeep.holla@arm.com, rjw@rjwysocki.net, lenb@kernel.org, will@kernel.org, robin.murphy@arm.com, bhelgaas@google.com, jonathan.cameron@huawei.com, zhangfei.gao@linaro.org References: <20191209180514.272727-1-jean-philippe@linaro.org> <20191209180514.272727-11-jean-philippe@linaro.org> From: Auger Eric Message-ID: <26230082-03d2-5c01-389a-9e32dd281b57@redhat.com> Date: Wed, 18 Dec 2019 10:59:36 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: <20191209180514.272727-11-jean-philippe@linaro.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi Jean, On 12/9/19 7:05 PM, Jean-Philippe Brucker wrote: > The SMMU can support up to 20 bits of SSID. Add a second level of page > tables to accommodate this. Devices that support more than 1024 SSIDs now > have a table of 1024 L1 entries (8kB), pointing to tables of 1024 context > descriptors (64kB), allocated on demand. > > Signed-off-by: Jean-Philippe Brucker > --- > drivers/iommu/arm-smmu-v3.c | 153 +++++++++++++++++++++++++++++++++--- > 1 file changed, 143 insertions(+), 10 deletions(-) > > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c > index fc5119f34187..52adcdfda58b 100644 > --- a/drivers/iommu/arm-smmu-v3.c > +++ b/drivers/iommu/arm-smmu-v3.c > @@ -224,6 +224,7 @@ > > #define STRTAB_STE_0_S1FMT GENMASK_ULL(5, 4) > #define STRTAB_STE_0_S1FMT_LINEAR 0 > +#define STRTAB_STE_0_S1FMT_64K_L2 2 > #define STRTAB_STE_0_S1CTXPTR_MASK GENMASK_ULL(51, 6) > #define STRTAB_STE_0_S1CDMAX GENMASK_ULL(63, 59) > > @@ -263,7 +264,20 @@ > > #define STRTAB_STE_3_S2TTB_MASK GENMASK_ULL(51, 4) > > -/* Context descriptor (stage-1 only) */ > +/* > + * Context descriptors. > + * > + * Linear: when less than 1024 SSIDs are supported > + * 2lvl: at most 1024 L1 entries, > + * 1024 lazy entries per table. > + */ > +#define CTXDESC_SPLIT 10 > +#define CTXDESC_L2_ENTRIES (1 << CTXDESC_SPLIT) > + > +#define CTXDESC_L1_DESC_DWORDS 1 > +#define CTXDESC_L1_DESC_VALID 1 > +#define CTXDESC_L1_DESC_L2PTR_MASK GENMASK_ULL(51, 12) > + > #define CTXDESC_CD_DWORDS 8 > #define CTXDESC_CD_0_TCR_T0SZ GENMASK_ULL(5, 0) > #define ARM64_TCR_T0SZ GENMASK_ULL(5, 0) > @@ -575,7 +589,10 @@ struct arm_smmu_cd_table { > }; > > struct arm_smmu_s1_cfg { > - struct arm_smmu_cd_table table; > + struct arm_smmu_cd_table *tables; > + size_t num_tables; > + __le64 *l1ptr; you may add a comment saying that l1ptr and l1ptr_dma are only set/used in non linear case and one comment saying that "tables" represent leaf tables. > + dma_addr_t l1ptr_dma; > struct arm_smmu_ctx_desc cd; > u8 s1fmt; > u8 s1cdmax; > @@ -1521,9 +1538,53 @@ static void arm_smmu_free_cd_leaf_table(struct arm_smmu_device *smmu, > { > size_t size = num_entries * (CTXDESC_CD_DWORDS << 3); > > + if (!table->ptr) > + return; > dmam_free_coherent(smmu->dev, size, table->ptr, table->ptr_dma); > } > > +static void arm_smmu_write_cd_l1_desc(__le64 *dst, > + struct arm_smmu_cd_table *table) > +{ > + u64 val = (table->ptr_dma & CTXDESC_L1_DESC_L2PTR_MASK) | > + CTXDESC_L1_DESC_VALID; > + > + WRITE_ONCE(*dst, cpu_to_le64(val)); > +} > + > +static __le64 *arm_smmu_get_cd_ptr(struct arm_smmu_domain *smmu_domain, > + u32 ssid) > +{ > + __le64 *l1ptr; > + unsigned int idx; > + struct arm_smmu_cd_table *table; > + struct arm_smmu_device *smmu = smmu_domain->smmu; > + struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg; > + > + if (cfg->s1fmt == STRTAB_STE_0_S1FMT_LINEAR) { > + table = &cfg->tables[0]; > + idx = ssid; > + } else { nit: you may avoid this extra indent by either returning above or go to a label. > + idx = ssid >> CTXDESC_SPLIT; > + if (idx >= cfg->num_tables) > + return NULL; > + > + table = &cfg->tables[idx]; > + if (!table->ptr) { > + if (arm_smmu_alloc_cd_leaf_table(smmu, table, > + CTXDESC_L2_ENTRIES)) > + return NULL; > + > + l1ptr = cfg->l1ptr + idx * CTXDESC_L1_DESC_DWORDS; > + arm_smmu_write_cd_l1_desc(l1ptr, table); > + /* An invalid L1CD can be cached */ > + arm_smmu_sync_cd(smmu_domain, ssid, false); > + } > + idx = ssid & (CTXDESC_L2_ENTRIES - 1); > + } > + return table->ptr + idx * CTXDESC_CD_DWORDS;> +} > + > static u64 arm_smmu_cpu_tcr_to_cd(u64 tcr) > { > u64 val = 0; > @@ -1556,8 +1617,10 @@ static int arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain, > u64 val; > bool cd_live; > struct arm_smmu_device *smmu = smmu_domain->smmu; > - __le64 *cdptr = smmu_domain->s1_cfg.table.ptr + ssid * > - CTXDESC_CD_DWORDS; > + __le64 *cdptr = arm_smmu_get_cd_ptr(smmu_domain, ssid); > + > + if (!cdptr) > + return -ENOMEM; -ENOMEM does not fit well with (idx >= cfg->num_tables) case Besides the idx is checked against the max table capacity only in non linear mode. Can't you check the ssid against cfg->s1cdmax earlier? > > val = le64_to_cpu(cdptr[0]); > cd_live = !!(val & CTXDESC_CD_0_V); > @@ -1604,20 +1667,87 @@ static int arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain, > > static int arm_smmu_alloc_cd_tables(struct arm_smmu_domain *smmu_domain) > { > + int ret; > + size_t size = 0; > + size_t max_contexts; > struct arm_smmu_device *smmu = smmu_domain->smmu; > struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg; > > - cfg->s1fmt = STRTAB_STE_0_S1FMT_LINEAR; > - return arm_smmu_alloc_cd_leaf_table(smmu, &cfg->table, > - 1 << cfg->s1cdmax); > + max_contexts = 1 << cfg->s1cdmax; > + > + if (!(smmu->features & ARM_SMMU_FEAT_2_LVL_CDTAB) || > + max_contexts <= CTXDESC_L2_ENTRIES) { > + cfg->s1fmt = STRTAB_STE_0_S1FMT_LINEAR; > + cfg->num_tables = 1; > + } else { > + cfg->s1fmt = STRTAB_STE_0_S1FMT_64K_L2; > + cfg->num_tables = DIV_ROUND_UP(max_contexts, > + CTXDESC_L2_ENTRIES); > + > + size = cfg->num_tables * (CTXDESC_L1_DESC_DWORDS << 3); > + cfg->l1ptr = dmam_alloc_coherent(smmu->dev, size, > + &cfg->l1ptr_dma, > + GFP_KERNEL); > + if (!cfg->l1ptr) { > + dev_warn(smmu->dev, > + "failed to allocate L1 context table\n"); > + return -ENOMEM; > + } > + } > + > + cfg->tables = devm_kzalloc(smmu->dev, sizeof(struct arm_smmu_cd_table) * > + cfg->num_tables, GFP_KERNEL); > + if (!cfg->tables) { > + ret = -ENOMEM; > + goto err_free_l1; > + } > + > + /* > + * Only allocate a leaf table for linear case. With two levels, leaf > + * tables are allocated lazily. > + */ > + if (!cfg->l1ptr) { > + ret = arm_smmu_alloc_cd_leaf_table(smmu, &cfg->tables[0], > + max_contexts); > + if (ret) > + goto err_free_tables; > + } > + > + return 0; > + > +err_free_tables: > + devm_kfree(smmu->dev, cfg->tables); > + cfg->tables = NULL; > +err_free_l1: > + if (cfg->l1ptr) { > + dmam_free_coherent(smmu->dev, size, cfg->l1ptr, cfg->l1ptr_dma); > + cfg->l1ptr = NULL; > + cfg->l1ptr_dma = 0; > + } > + return ret; > } > > static void arm_smmu_free_cd_tables(struct arm_smmu_domain *smmu_domain) > { > + int i; > struct arm_smmu_device *smmu = smmu_domain->smmu; > struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg; > + size_t num_leaf_entries = 1 << cfg->s1cdmax; > + struct arm_smmu_cd_table *table = cfg->tables; > + > + if (cfg->l1ptr) { > + size_t size = cfg->num_tables * (CTXDESC_L1_DESC_DWORDS << 3); > > - arm_smmu_free_cd_leaf_table(smmu, &cfg->table, 1 << cfg->s1cdmax); > + dmam_free_coherent(smmu->dev, size, cfg->l1ptr, cfg->l1ptr_dma); > + cfg->l1ptr = NULL; > + cfg->l1ptr_dma = 0; > + num_leaf_entries = CTXDESC_L2_ENTRIES; > + } > + > + for (i = 0; i < cfg->num_tables; i++, table++) > + arm_smmu_free_cd_leaf_table(smmu, table, num_leaf_entries); > + devm_kfree(smmu->dev, cfg->tables); > + cfg->tables = NULL; > } > > /* Stream table manipulation functions */ > @@ -1737,6 +1867,9 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid, > } > > if (s1_cfg) { > + dma_addr_t ptr_dma = s1_cfg->l1ptr ? s1_cfg->l1ptr_dma : > + s1_cfg->tables[0].ptr_dma; > + > BUG_ON(ste_live); > dst[1] = cpu_to_le64( > FIELD_PREP(STRTAB_STE_1_S1DSS, STRTAB_STE_1_S1DSS_SSID0) | > @@ -1749,7 +1882,7 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid, > !(smmu->features & ARM_SMMU_FEAT_STALL_FORCE)) > dst[1] |= cpu_to_le64(STRTAB_STE_1_S1STALLD); > > - val |= (s1_cfg->table.ptr_dma & STRTAB_STE_0_S1CTXPTR_MASK) | > + val |= (ptr_dma & STRTAB_STE_0_S1CTXPTR_MASK) | > FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_S1_TRANS) | > FIELD_PREP(STRTAB_STE_0_S1CDMAX, s1_cfg->s1cdmax) | > FIELD_PREP(STRTAB_STE_0_S1FMT, s1_cfg->s1fmt); > @@ -2265,7 +2398,7 @@ static void arm_smmu_domain_free(struct iommu_domain *domain) > if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) { > struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg; > > - if (cfg->table.ptr) { > + if (cfg->tables) { > arm_smmu_free_cd_tables(smmu_domain); > arm_smmu_bitmap_free(smmu->asid_map, cfg->cd.asid); > } > Otherwise looks good to me. Thanks Eric