From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Re: [PATCH] OMAP: iommu flush page table entries from L1 and L2 cache Date: Mon, 18 Apr 2011 14:05:08 +0300 Message-ID: <20110418110502.GI12272@atomide.com> References: <1302817968-28516-1-git-send-email-fernando.lugo@ti.com> <20110414223036.GA7335@n2100.arm.linux.org.uk> <201104180929.33569.arnd@arndb.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mho-01-ewr.mailhop.org ([204.13.248.71]:14292 "EHLO mho-01-ewr.mailhop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750832Ab1DRLFO (ORCPT ); Mon, 18 Apr 2011 07:05:14 -0400 Content-Disposition: inline In-Reply-To: <201104180929.33569.arnd@arndb.de> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Arnd Bergmann Cc: Russell King - ARM Linux , Fernando Guzman Lugo , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Ramesh Gupta , Hari Kanigeri , Hiroshi DOYU * Arnd Bergmann [110418 10:26]: > On Friday 15 April 2011, Russell King - ARM Linux wrote: > > On Thu, Apr 14, 2011 at 04:52:48PM -0500, Fernando Guzman Lugo wrote: > > > From: Ramesh Gupta > > > > > > This patch is to flush the iommu page table entries from L1 and L2 > > > caches using dma_map_single. This also simplifies the implementation > > > by removing the functions flush_iopgd_range/flush_iopte_range. > > > > No. This usage is just wrong. If you're going to use the DMA API then > > unmap it, otherwise the DMA API debugging will go awol. > > > It's also completely upside-down: The iommu support should provide interfaces > using the dma-mapping API, not use that API to provide a machine specific > version of the generic interface. > > As far as I can tell, nothing actually uses these drivers, maybe we should just > remove them before we get any code in the mainline kernel that depends on it. There is drivers/media/video/omap3isp/isp.c. But if we now have a generic replacement for this code we should start using it. Hiroshi, any comments on that? Regards, Tony