Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751506AbdHaI30 (ORCPT ); Thu, 31 Aug 2017 04:29:26 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:5496 "EHLO szxga04-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751040AbdHaI3U (ORCPT ); Thu, 31 Aug 2017 04:29:20 -0400 From: Yisheng Xie To: CC: , , , , , , , , , , , , , , , , , , , , Subject: [RFC PATCH 1/6] dt-bindings: document stall and PASID properties for IOMMU masters Date: Thu, 31 Aug 2017 16:20:37 +0800 Message-ID: <1504167642-14922-2-git-send-email-xieyisheng1@huawei.com> X-Mailer: git-send-email 1.7.12.4 In-Reply-To: <1504167642-14922-1-git-send-email-xieyisheng1@huawei.com> References: <1504167642-14922-1-git-send-email-xieyisheng1@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.175.102.37] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A010203.59A7C8DB.002E,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 8ba126ef6085750d0f2fbf455daa2042 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1511 Lines: 35 From: Jean-Philippe Brucker Document the bindings for stall and PASID capable platform devices. Signed-off-by: Jean-Philippe Brucker --- Documentation/devicetree/bindings/iommu/iommu.txt | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/Documentation/devicetree/bindings/iommu/iommu.txt b/Documentation/devicetree/bindings/iommu/iommu.txt index 5a8b462..7355d7f 100644 --- a/Documentation/devicetree/bindings/iommu/iommu.txt +++ b/Documentation/devicetree/bindings/iommu/iommu.txt @@ -86,6 +86,19 @@ have a means to turn off translation. But it is invalid in such cases to disable the IOMMU's device tree node in the first place because it would prevent any driver from properly setting up the translations. +Optional properties: +-------------------- +- dma-can-stall: When present, the master can wait for a DMA transaction + to be handled by the IOMMU and can recover from a fault. For example, if + the page accessed by the DMA transaction isn't mapped, some IOMMUs are + able to stall the transaction and let the OS populate the page tables. + The IOMMU then performs the transaction if the fault was successfully + handled, or aborts the transaction otherwise. + +- pasid-bits: Some masters support multiple address spaces for DMA. By + tagging DMA transactions with an address space identifier. By default, + this is 0, which means that the device only has one address space. + Notes: ====== -- 1.7.12.4