From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752130AbbASNkz (ORCPT ); Mon, 19 Jan 2015 08:40:55 -0500 Received: from mout.kundenserver.de ([212.227.126.131]:63880 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751467AbbASNkx (ORCPT ); Mon, 19 Jan 2015 08:40:53 -0500 From: Arnd Bergmann To: Rameshwar Prasad Sahu Cc: vinod.koul@intel.com, dan.j.williams@intel.com, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, ddutile@redhat.com, jcm@redhat.com, patches@apm.com, Loc Ho Subject: Re: [PATCH v3 2/3] arm64: dts: Add APM X-Gene DMA device and DMA clock DTS nodes Date: Mon, 19 Jan 2015 14:40:36 +0100 Message-ID: <2407238.x2YxDm0cd4@wuerfel> User-Agent: KMail/4.11.5 (Linux/3.16.0-10-generic; KDE/4.11.5; x86_64; ; ) In-Reply-To: <1421671269-19441-3-git-send-email-rsahu@apm.com> References: <1421671269-19441-1-git-send-email-rsahu@apm.com> <1421671269-19441-3-git-send-email-rsahu@apm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Provags-ID: V03:K0:VRBRF0i/dcmH03ao0uTKXfLCd8CWIrWqqJd81+mhiepvd3z0eNF siSbZ0iA75z3JIKua/+16YXknY+4MawwJHcC1n4uXApJXd4WaKztBM4uYIZVl4hM1TFmUY5 sMYYwhZtayHhxbLYSahgB5JWc8WqxZLmEG8kICw6bNBpqeSu8ezy0UJdUI/Q/AXkX/f3T36 B4SAmhta1ELjbkPSUqxHQ== X-UI-Out-Filterresults: notjunk:1; Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Monday 19 January 2015 18:11:08 Rameshwar Prasad Sahu wrote: > diff --git a/arch/arm64/boot/dts/apm/apm-storm.dtsi b/arch/arm64/boot/dts/apm/apm-storm.dtsi > index f1ad9c2..e20da23 100644 > --- a/arch/arm64/boot/dts/apm/apm-storm.dtsi > +++ b/arch/arm64/boot/dts/apm/apm-storm.dtsi > @@ -103,6 +103,9 @@ > #size-cells = <2>; > ranges; > > + /* DDR range is 42-bit addressing */ > + dma-ranges = <0x40 0x0 0x40 0x0 0x1ff 0xffffffff>; > + > The comment above is misleading, and the value is wrong. I assume you copied these from the AMD patch that introduced the respective property. The value should be dma-ranges = <0x40 0x0 0x40 0x0 0x200 0>; to say that any DMA to physical addresses from 0 to 0x3f.ffffffff is disallowed and dma to physical addresses from 0x40.00000000 to 0x23f.ffffffff is allowed and gets translated using an identity mapping. I also see that on Mustang, all memory is outside of this range, which is a bit suspicious, while your PCI memory space is included. It would be best to match the numbers up with your data sheet. Arnd