From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752585Ab0HSKbw (ORCPT ); Thu, 19 Aug 2010 06:31:52 -0400 Received: from gate.crashing.org ([63.228.1.57]:43227 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752471Ab0HSKbu (ORCPT ); Thu, 19 Aug 2010 06:31:50 -0400 Subject: Re: ARM: 2.6.3[45] PCI regression (IXP4xx and PXA?) From: Benjamin Herrenschmidt To: FUJITA Tomonori Cc: linux@arm.linux.org.uk, khc@pm.waw.pl, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org In-Reply-To: <20100814181306U.fujita.tomonori@lab.ntt.co.jp> References: <20100811072532.GA21511@n2100.arm.linux.org.uk> <20100813152224H.fujita.tomonori@lab.ntt.co.jp> <20100813215413.GA21607@n2100.arm.linux.org.uk> <20100814181306U.fujita.tomonori@lab.ntt.co.jp> Content-Type: text/plain; charset="UTF-8" Date: Thu, 19 Aug 2010 20:31:22 +1000 Message-ID: <1282213882.22370.360.camel@pasglop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2010-08-14 at 18:30 +0900, FUJITA Tomonori wrote: > > A long solution would be having two dma_mask for a device and a > bus. We also need something to represent a DMA-capable range instead > of the dma mask. I'd rather have the arch (aka the bus) be able to filter the mask, better than having to deal with multiple masks in the generic code. Besides, in embedded-land, you never know how many busses are stacked before you reach the device, ie, you'd end up having to AND quite a few masks before getting there in some cases. Sounds better to establish that once, at set_coherent_dma_mask() time. Cheers, Ben. From mboxrd@z Thu Jan 1 00:00:00 1970 From: benh@kernel.crashing.org (Benjamin Herrenschmidt) Date: Thu, 19 Aug 2010 20:31:22 +1000 Subject: ARM: 2.6.3[45] PCI regression (IXP4xx and PXA?) In-Reply-To: <20100814181306U.fujita.tomonori@lab.ntt.co.jp> References: <20100811072532.GA21511@n2100.arm.linux.org.uk> <20100813152224H.fujita.tomonori@lab.ntt.co.jp> <20100813215413.GA21607@n2100.arm.linux.org.uk> <20100814181306U.fujita.tomonori@lab.ntt.co.jp> Message-ID: <1282213882.22370.360.camel@pasglop> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Sat, 2010-08-14 at 18:30 +0900, FUJITA Tomonori wrote: > > A long solution would be having two dma_mask for a device and a > bus. We also need something to represent a DMA-capable range instead > of the dma mask. I'd rather have the arch (aka the bus) be able to filter the mask, better than having to deal with multiple masks in the generic code. Besides, in embedded-land, you never know how many busses are stacked before you reach the device, ie, you'd end up having to AND quite a few masks before getting there in some cases. Sounds better to establish that once, at set_coherent_dma_mask() time. Cheers, Ben.