From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-132.freemail.mail.aliyun.com (out30-132.freemail.mail.aliyun.com [115.124.30.132]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 94F0F3DA7E3 for ; Tue, 15 Sep 2026 03:28:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.132 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789442922; cv=none; b=EG+GdNkOED3OXFyn/QVIFFBP3Jifz/zuUZfZpwqnCCp3DkjYUpwDlLr7PrO4pGxSHhboyKcziUdfdkpj2hAb45uFQlgRpoaTh+aS9LcHS8eaDEReAC9zN67ArF23UU17J1fUyU14B35LfjR4aJdQYWzyfWB7GcSrRbN+XwFdoLM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789442922; c=relaxed/simple; bh=T9WWqFJHchi/0d/r1QqY1VcFw/wXeEsnz4BNMR0PRPE=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=BrI8NEHYVs9neDiH2FeQ9iSEhCmAzUBneZoNGQgg/xgfYkfa+Ccg6WUZPUggoUZO7rAE547a5ovNzo3QyEwETyCPo1ljZYJgfG6g3T0koN9yJpK/JVvYm5TM3w2cX1yiAYKCnwFcy0UrKZYTv5RcAtxh7AtDSngyXMCRWCfpW/4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=gAkeWCFU; arc=none smtp.client-ip=115.124.30.132 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="gAkeWCFU" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1789442916; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=vV2Y5T1kVnTXHiV+qTqs8GbZEVnLFhK5H2hev57N6Io=; b=gAkeWCFUHZ3rFcp4f4D325IjRULrl/pFfrR0H0i7WPBxVb3z1RJKTacURCXRsBoChBJ7lpQ8NoOd++BnvbC2GOlZ/CZ/vdh19Q/8dfaAl9v1Art6QMOl3oinq9likhyNGoX9xzsJcqxlnkIVFspQknnJO5SQ/SZBy/PInjsVMYA= X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R191e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033045133197;MF=fangyu.yu@linux.alibaba.com;NM=1;PH=DS;RN=26;SR=0;TI=SMTPD_---0XB.uvNY_1789442913; Received: from localhost.localdomain(mailfrom:fangyu.yu@linux.alibaba.com fp:SMTPD_---0XB.uvNY_1789442913 cluster:ay36) by smtp.aliyun-inc.com; Tue, 15 Sep 2026 11:28:34 +0800 From: fangyu.yu@linux.alibaba.com To: tomasz.jeznach@linux.dev, joro@8bytes.org, will@kernel.org, robin.murphy@arm.com, pjw@kernel.org, palmer@dabbelt.com, aou@eecs.berkeley.edu, alex@ghiti.fr, baolu.lu@linux.intel.com, jroedel@suse.de, zong.li@sifive.com, andrew.jones@oss.qualcomm.com, anup@brainfault.org, jgg@nvidia.com, jgg@ziepe.ca, kevin.tian@intel.com, atish.patra@linux.dev, skhawaja@google.com, vasant.hegde@amd.com, joerg.roedel@amd.com Cc: fangyu.yu@linux.alibaba.com, guoren@kernel.org, iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, kvm-riscv@lists.infradead.org Subject: [RFC PATCH v4 01/10] iommupt: Add RISC-V Second-stage (iohgatp) page table support Date: Tue, 15 Sep 2026 11:28:20 +0800 Message-Id: <20260915032828.11250-2-fangyu.yu@linux.alibaba.com> X-Mailer: git-send-email 2.39.3 (Apple Git-146) In-Reply-To: <20260915032828.11250-1-fangyu.yu@linux.alibaba.com> References: <20260915032828.11250-1-fangyu.yu@linux.alibaba.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Fangyu Yu Add support for Sv39x4/Sv48x4/Sv57x4 Second-stage page tables used by the RISC-V IOMMU iohgatp register. The x4 root page table is 16 KiB instead of the usual 4 KiB, covering 2 extra GPA bits (hw_max_vasz_lg2 = 41/50/59). Signed-off-by: Fangyu Yu --- drivers/iommu/generic_pt/fmt/iommu_riscv64.c | 2 +- drivers/iommu/generic_pt/fmt/riscv.h | 109 +++++++++++++++---- include/linux/generic_pt/common.h | 4 + include/linux/generic_pt/iommu.h | 11 ++ 4 files changed, 102 insertions(+), 24 deletions(-) diff --git a/drivers/iommu/generic_pt/fmt/iommu_riscv64.c b/drivers/iommu/generic_pt/fmt/iommu_riscv64.c index 1bb74114fb02..fa61839e5599 100644 --- a/drivers/iommu/generic_pt/fmt/iommu_riscv64.c +++ b/drivers/iommu/generic_pt/fmt/iommu_riscv64.c @@ -8,7 +8,7 @@ (BIT(PT_FEAT_SIGN_EXTEND) | BIT(PT_FEAT_FLUSH_RANGE) | \ BIT(PT_FEAT_RISCV_SVNAPOT_64K) | \ BIT(PT_FEAT_DETAILED_GATHER) | \ - BIT(PT_FEAT_RISCV_SVPBMT)) + BIT(PT_FEAT_RISCV_SVPBMT) | BIT(PT_FEAT_RISCV_S2)) #define PT_FORCE_ENABLED_FEATURES BIT(PT_FEAT_DETAILED_GATHER) #include "iommu_template.h" diff --git a/drivers/iommu/generic_pt/fmt/riscv.h b/drivers/iommu/generic_pt/fmt/riscv.h index ae9a76514416..d4445e463fa9 100644 --- a/drivers/iommu/generic_pt/fmt/riscv.h +++ b/drivers/iommu/generic_pt/fmt/riscv.h @@ -37,7 +37,16 @@ enum { PT_MAX_OUTPUT_ADDRESS_LG2 = 34, PT_MAX_TOP_LEVEL = 1, #else - PT_MAX_VA_ADDRESS_LG2 = 57, + /* + * PT_MAX_VA_ADDRESS_LG2 is the upper bound accepted by the generic + * pt_iommu_init() range check. It must cover both first-stage and + * second-stage (G-stage) modes: + * + * First-stage (fsc/iosatp): Sv39=39, Sv48=48, Sv57=57 + * Second-stage (iohgatp): Sv39x4=41, Sv48x4=50, Sv57x4=59 + * + */ + PT_MAX_VA_ADDRESS_LG2 = 59, PT_MAX_OUTPUT_ADDRESS_LG2 = 56, PT_MAX_TOP_LEVEL = 4, #endif @@ -126,6 +135,12 @@ riscvpt_entry_num_contig_lg2(const struct pt_state *pts) static inline unsigned int riscvpt_num_items_lg2(const struct pt_state *pts) { + /* + * It is not allowed to call pt_num_items_lg2() at the top level, this + * API restriction is specifically an optimization avoid overheads + * dealing with concatenated tables here. + */ + PT_WARN_ON(pts->level == pts->range->top_level); return PT_TABLEMEM_LG2SZ - ilog2(sizeof(u64)); } #define pt_num_items_lg2 riscvpt_num_items_lg2 @@ -261,20 +276,41 @@ riscvpt_iommu_fmt_init(struct pt_iommu_riscv_64 *iommu_table, const struct pt_iommu_riscv_64_cfg *cfg) { struct pt_riscv *table = &iommu_table->riscv_64pt; - - switch (cfg->common.hw_max_vasz_lg2) { - case 39: - pt_top_set_level(&table->common, 2); - break; - case 48: - pt_top_set_level(&table->common, 3); - break; - case 57: - pt_top_set_level(&table->common, 4); - break; - default: - return -EINVAL; + unsigned int top_level; + + if (pt_feature(&table->common, PT_FEAT_RISCV_S2)) { + /* Second-stage (iohgatp): Sv39x4 / Sv48x4 / Sv57x4. */ + switch (cfg->common.hw_max_vasz_lg2) { + case 41: + top_level = 2; + break; + case 50: + top_level = 3; + break; + case 59: + top_level = 4; + break; + default: + return -EINVAL; + } + } else { + /* First-stage (fsc/iosatp): Sv39 / Sv48 / Sv57. */ + switch (cfg->common.hw_max_vasz_lg2) { + case 39: + top_level = 2; + break; + case 48: + top_level = 3; + break; + case 57: + top_level = 4; + break; + default: + return -EINVAL; + } } + + pt_top_set_level(&table->common, top_level); table->common.max_oasz_lg2 = min(PT_MAX_OUTPUT_ADDRESS_LG2, cfg->common.hw_max_oasz_lg2); return 0; @@ -292,30 +328,57 @@ riscvpt_iommu_fmt_hw_info(struct pt_iommu_riscv_64 *table, PT_WARN_ON(top_phys & ~PT_TOP_PHYS_MASK); /* - * See Table 3. Encodings of iosatp.MODE field" for DC.tx.SXL = 0: - * 8 = Sv39 = top level 2 - * 9 = Sv38 = top level 3 - * 10 = Sv57 = top level 4 + * Both first-stage (fsc/iosatp) and second-stage (iohgatp) share the + * same MODE numeric values for a given top level: + * top_level 2 -> MODE 8 (Sv39 / Sv39x4) + * top_level 3 -> MODE 9 (Sv48 / Sv48x4) + * top_level 4 -> MODE 10 (Sv57 / Sv57x4) + * + * See "Table 3. Encodings of iosatp.MODE field" (DC.tc.SXL = 0) and + * "Table 2. Encoding of iohgatp.MODE field" in the RISC-V IOMMU spec. */ - info->fsc_iosatp_mode = top_range->top_level + 6; + if (pt_feature(&table->riscv_64pt.common, PT_FEAT_RISCV_S2)) + info->iohgatp_mode = top_range->top_level + 6; + else + info->fsc_iosatp_mode = top_range->top_level + 6; } #define pt_iommu_fmt_hw_info riscvpt_iommu_fmt_hw_info #if defined(GENERIC_PT_KUNIT) static const struct pt_iommu_riscv_64_cfg riscv_64_kunit_fmt_cfgs[] = { - [0] = { .common.features = BIT(PT_FEAT_RISCV_SVNAPOT_64K), + /* First-stage (fsc/iosatp): Sv39 / Sv48 / Sv57 */ + [0] = { .common.features = BIT(PT_FEAT_SIGN_EXTEND) | + BIT(PT_FEAT_RISCV_SVNAPOT_64K), .common.hw_max_oasz_lg2 = 56, .common.hw_max_vasz_lg2 = 39 }, - [1] = { .common.features = 0, + [1] = { .common.features = BIT(PT_FEAT_SIGN_EXTEND), .common.hw_max_oasz_lg2 = 56, .common.hw_max_vasz_lg2 = 48 }, - [2] = { .common.features = BIT(PT_FEAT_RISCV_SVNAPOT_64K), + [2] = { .common.features = BIT(PT_FEAT_SIGN_EXTEND) | + BIT(PT_FEAT_RISCV_SVNAPOT_64K), .common.hw_max_oasz_lg2 = 56, .common.hw_max_vasz_lg2 = 57 }, + /* + * Second-stage (iohgatp): Sv39x4 / Sv48x4 / Sv57x4. + */ + [3] = { .common.features = BIT(PT_FEAT_RISCV_S2) | + BIT(PT_FEAT_RISCV_SVNAPOT_64K), + .common.hw_max_oasz_lg2 = 56, + .common.hw_max_vasz_lg2 = 41 }, + [4] = { .common.features = BIT(PT_FEAT_RISCV_S2), + .common.hw_max_oasz_lg2 = 56, + .common.hw_max_vasz_lg2 = 50 }, + [5] = { .common.features = BIT(PT_FEAT_RISCV_S2) | + BIT(PT_FEAT_RISCV_SVNAPOT_64K), + .common.hw_max_oasz_lg2 = 56, + .common.hw_max_vasz_lg2 = 59 }, }; #define kunit_fmt_cfgs riscv_64_kunit_fmt_cfgs +/* Sign extension is only valid for first-stage configs, not S2. */ enum { - KUNIT_FMT_FEATURES = BIT(PT_FEAT_RISCV_SVNAPOT_64K), + KUNIT_FMT_FEATURES = BIT(PT_FEAT_SIGN_EXTEND) | + BIT(PT_FEAT_RISCV_SVNAPOT_64K) | + BIT(PT_FEAT_RISCV_S2), }; #endif diff --git a/include/linux/generic_pt/common.h b/include/linux/generic_pt/common.h index 07ef1c8341a4..f2e130c2b804 100644 --- a/include/linux/generic_pt/common.h +++ b/include/linux/generic_pt/common.h @@ -197,6 +197,10 @@ enum { * Support Svpbmt extension: encode page-based memory type (PBMT) in PTEs. */ PT_FEAT_RISCV_SVPBMT, + /* + * Using second-stage / iohgatp address translation. + */ + PT_FEAT_RISCV_S2, }; diff --git a/include/linux/generic_pt/iommu.h b/include/linux/generic_pt/iommu.h index dd0edd02a48a..2eed9b78f56c 100644 --- a/include/linux/generic_pt/iommu.h +++ b/include/linux/generic_pt/iommu.h @@ -328,7 +328,18 @@ struct pt_iommu_riscv_64_cfg { struct pt_iommu_riscv_64_hw_info { u64 ppn; + /* + * First-stage (fsc/iosatp) MODE encoding: + * 8 = Sv39, 9 = Sv48, 10 = Sv57 + * Used to program DC.fsc.iosatp.MODE. + */ u8 fsc_iosatp_mode; + /* + * Second-stage (iohgatp) MODE encoding: + * 8 = Sv39x4, 9 = Sv48x4, 10 = Sv57x4 + * Used to program DC.iohgatp.MODE. + */ + u8 iohgatp_mode; }; IOMMU_FORMAT(riscv_64, riscv_64pt); -- 2.50.1