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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 DB5F8C433DB for ; Mon, 1 Feb 2021 01:19:12 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (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 49DBC64E15 for ; Mon, 1 Feb 2021 01:19:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 49DBC64E15 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=hisilicon.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id 0EBF386FCD; Mon, 1 Feb 2021 01:19:12 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id CQiVaL8lLfbZ; Mon, 1 Feb 2021 01:19:11 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by hemlock.osuosl.org (Postfix) with ESMTP id 6B72A86FCF; Mon, 1 Feb 2021 01:19:11 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 577DCC0174; Mon, 1 Feb 2021 01:19:11 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 1C179C013A for ; Mon, 1 Feb 2021 01:19:09 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id E7C9B86FCF for ; Mon, 1 Feb 2021 01:19:08 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 4OBvlt+yJddR for ; Mon, 1 Feb 2021 01:19:07 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from szxga07-in.huawei.com (szxga07-in.huawei.com [45.249.212.35]) by hemlock.osuosl.org (Postfix) with ESMTPS id 4CD8786FCD for ; Mon, 1 Feb 2021 01:19:07 +0000 (UTC) Received: from DGGEMS407-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga07-in.huawei.com (SkyGuard) with ESMTP id 4DTVRt2HX5z7dlT; Mon, 1 Feb 2021 09:17:46 +0800 (CST) Received: from [127.0.0.1] (10.40.188.87) by DGGEMS407-HUB.china.huawei.com (10.3.19.207) with Microsoft SMTP Server id 14.3.498.0; Mon, 1 Feb 2021 09:18:52 +0800 Subject: Re: [PATCH v12 10/10] iommu/arm-smmu-v3: Add stall support for platform devices To: Jean-Philippe Brucker , , References: <20210127154322.3959196-1-jean-philippe@linaro.org> <20210127154322.3959196-11-jean-philippe@linaro.org> From: Zhou Wang Message-ID: <8adc79cc-7afb-dfe8-4f7b-07fa6dc5b905@hisilicon.com> Date: Mon, 1 Feb 2021 09:18:42 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.7.1 MIME-Version: 1.0 In-Reply-To: <20210127154322.3959196-11-jean-philippe@linaro.org> X-Originating-IP: [10.40.188.87] X-CFilter-Loop: Reflected Cc: devicetree@vger.kernel.org, kevin.tian@intel.com, linux-acpi@vger.kernel.org, sudeep.holla@arm.com, rjw@rjwysocki.net, vivek.gautam@arm.com, iommu@lists.linux-foundation.org, robh+dt@kernel.org, linux-accelerators@lists.ozlabs.org, guohanjun@huawei.com, zhangfei.gao@linaro.org, robin.murphy@arm.com, linux-arm-kernel@lists.infradead.org, lenb@kernel.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On 2021/1/27 23:43, Jean-Philippe Brucker wrote: > The SMMU provides a Stall model for handling page faults in platform > devices. It is similar to PCIe PRI, but doesn't require devices to have > their own translation cache. Instead, faulting transactions are parked > and the OS is given a chance to fix the page tables and retry the > transaction. > > Enable stall for devices that support it (opt-in by firmware). When an > event corresponds to a translation error, call the IOMMU fault handler. > If the fault is recoverable, it will call us back to terminate or > continue the stall. > > To use stall device drivers need to enable IOMMU_DEV_FEAT_IOPF, which > initializes the fault queue for the device. > > Tested-by: Zhangfei Gao > Reviewed-by: Jonathan Cameron > Signed-off-by: Jean-Philippe Brucker > --- > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 43 ++++ > .../iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 59 +++++- > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 189 +++++++++++++++++- > 3 files changed, 276 insertions(+), 15 deletions(-) > [...] > @@ -1033,8 +1076,7 @@ int arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain, int ssid, > FIELD_PREP(CTXDESC_CD_0_ASID, cd->asid) | > CTXDESC_CD_0_V; > > - /* STALL_MODEL==0b10 && CD.S==0 is ILLEGAL */ > - if (smmu->features & ARM_SMMU_FEAT_STALL_FORCE) > + if (smmu_domain->stall_enabled) Could we add ssid checking here? like: if (smmu_domain->stall_enabled && ssid). The reason is if not CD.S will also be set when ssid is 0, which is not needed. Best, Zhou > val |= CTXDESC_CD_0_S; > } > > @@ -1278,7 +1320,7 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid, > FIELD_PREP(STRTAB_STE_1_STRW, strw)); > > if (smmu->features & ARM_SMMU_FEAT_STALLS && > - !(smmu->features & ARM_SMMU_FEAT_STALL_FORCE)) > + !master->stall_enabled) > dst[1] |= cpu_to_le64(STRTAB_STE_1_S1STALLD); > > val |= (s1_cfg->cdcfg.cdtab_dma & STRTAB_STE_0_S1CTXPTR_MASK) | [...] _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu