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=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 4BB7EC433DB for ; Tue, 9 Feb 2021 06:49:11 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 7835064E10 for ; Tue, 9 Feb 2021 06:49:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7835064E10 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4DZYQX3Pd0zDshs for ; Tue, 9 Feb 2021 17:49:08 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=chromium.org (client-ip=2607:f8b0:4864:20::432; helo=mail-pf1-x432.google.com; envelope-from=tientzu@chromium.org; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=chromium.org header.i=@chromium.org header.a=rsa-sha256 header.s=google header.b=I1pOI9d2; dkim-atps=neutral Received: from mail-pf1-x432.google.com (mail-pf1-x432.google.com [IPv6:2607:f8b0:4864:20::432]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4DZXrm3pvnzDsdq for ; Tue, 9 Feb 2021 17:23:20 +1100 (AEDT) Received: by mail-pf1-x432.google.com with SMTP id q20so11248643pfu.8 for ; Mon, 08 Feb 2021 22:23:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=eRi8Yzf5Y8qG5991xxXPsSC5LTyacs0FIIEghf5qlqE=; b=I1pOI9d2uMAOj25XXD6wAuAIs02PiqHn3vYbrTGQfRLUalLAaaWHj4AP66p1gZRw6c B3Fs+yS4m4TscPVDCU+jECnoKxyq5OcojOQ3UlsKgJX/2bKZw0g3cUyt8Lb9tyEzB+I7 d4RC5Ezyz3o4oj5hhy8N+DKnKQ48mOYCkG1WM= 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=eRi8Yzf5Y8qG5991xxXPsSC5LTyacs0FIIEghf5qlqE=; b=XDk0gTUDOJerzSeSTF2m19AnkgWVa0qzKV1LbaX1Vi+ZrDT5+CqQ5LAPPZkESNheFY In6cGgLIxHcmjAK/VQTuwgec2129b4FRFNzAMDpPkVEWOTyu94UtcEoxjhBuZVv/5fJC Fqj3fwfr1bUB4j8kGe/Ph7RPYTf/hl12MTrvzeBpMz6tDpC68eXUPqHfhWa7D/mqxxWu fp852mo0cmpaPo6SpMjUAsxN4CoVeMITt17vI8/fa7Qh6KD0NYQVKrQBD6NrQeEZmJ50 4F2eVGiZxwhrresSmb+SynoJQZRjkOOaFJc0iilf0oZZnHZOMJrH31dfm4QCAaQyC7Gy LCZA== X-Gm-Message-State: AOAM5318DANw8x5AH07khgmNqkbCTe/bkutzFKFIBAZXKpy+a/xhVcq+ qEhHJbiV4RjZQPrzsl6AfsYHlA== X-Google-Smtp-Source: ABdhPJxkt3Ed7T7cJDKzmZe4wszjCxFAf1leiOQT2ICOasIg3V/FKQTBEDaG8y6oYK6K58aSdM216A== X-Received: by 2002:a05:6a00:a8d:b029:1ba:71d1:fe3c with SMTP id b13-20020a056a000a8db02901ba71d1fe3cmr21262398pfl.51.1612851797444; Mon, 08 Feb 2021 22:23:17 -0800 (PST) Received: from localhost ([2401:fa00:1:10:a106:46e1:a999:81df]) by smtp.gmail.com with UTF8SMTPSA id a8sm1160332pjs.40.2021.02.08.22.23.12 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 08 Feb 2021 22:23:16 -0800 (PST) From: Claire Chang To: Rob Herring , mpe@ellerman.id.au, Joerg Roedel , Will Deacon , Frank Rowand , Konrad Rzeszutek Wilk , boris.ostrovsky@oracle.com, jgross@suse.com, Christoph Hellwig , Marek Szyprowski Subject: [PATCH v4 13/14] dt-bindings: of: Add restricted DMA pool Date: Tue, 9 Feb 2021 14:21:30 +0800 Message-Id: <20210209062131.2300005-14-tientzu@chromium.org> X-Mailer: git-send-email 2.30.0.478.g8a0d178c01-goog In-Reply-To: <20210209062131.2300005-1-tientzu@chromium.org> References: <20210209062131.2300005-1-tientzu@chromium.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: heikki.krogerus@linux.intel.com, peterz@infradead.org, grant.likely@arm.com, paulus@samba.org, mingo@kernel.org, sstabellini@kernel.org, Saravana Kannan , xypron.glpk@gmx.de, "Rafael J . Wysocki" , Bartosz Golaszewski , xen-devel@lists.xenproject.org, Thierry Reding , linux-devicetree , linuxppc-dev@lists.ozlabs.org, Nicolas Boichat , Claire Chang , Dan Williams , Andy Shevchenko , Greg KH , Randy Dunlap , lkml , "list@263.net:IOMMU DRIVERS" , Jim Quinlan , Robin Murphy , bauerman@linux.ibm.com Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Introduce the new compatible string, restricted-dma-pool, for restricted DMA. One can specify the address and length of the restricted DMA memory region by restricted-dma-pool in the reserved-memory node. Signed-off-by: Claire Chang --- .../reserved-memory/reserved-memory.txt | 24 +++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt b/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt index e8d3096d922c..fc9a12c2f679 100644 --- a/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt +++ b/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt @@ -51,6 +51,20 @@ compatible (optional) - standard definition used as a shared pool of DMA buffers for a set of devices. It can be used by an operating system to instantiate the necessary pool management subsystem if necessary. + - restricted-dma-pool: This indicates a region of memory meant to be + used as a pool of restricted DMA buffers for a set of devices. The + memory region would be the only region accessible to those devices. + When using this, the no-map and reusable properties must not be set, + so the operating system can create a virtual mapping that will be used + for synchronization. The main purpose for restricted DMA is to + mitigate the lack of DMA access control on systems without an IOMMU, + which could result in the DMA accessing the system memory at + unexpected times and/or unexpected addresses, possibly leading to data + leakage or corruption. The feature on its own provides a basic level + of protection against the DMA overwriting buffer contents at + unexpected times. However, to protect against general data leakage and + system memory corruption, the system needs to provide way to lock down + the memory access, e.g., MPU. - vendor specific string in the form ,[-] no-map (optional) - empty property - Indicates the operating system must not create a virtual mapping @@ -120,6 +134,11 @@ one for multimedia processing (named multimedia-memory@77000000, 64MiB). compatible = "acme,multimedia-memory"; reg = <0x77000000 0x4000000>; }; + + restricted_dma_mem_reserved: restricted_dma_mem_reserved { + compatible = "restricted-dma-pool"; + reg = <0x50000000 0x400000>; + }; }; /* ... */ @@ -138,4 +157,9 @@ one for multimedia processing (named multimedia-memory@77000000, 64MiB). memory-region = <&multimedia_reserved>; /* ... */ }; + + pcie_device: pcie_device@0,0 { + memory-region = <&restricted_dma_mem_reserved>; + /* ... */ + }; }; -- 2.30.0.478.g8a0d178c01-goog