From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kumar Gala Subject: Re: [PATCH 1/4] ucc_geth: Change private immrbar_virt_to_phys to generic iopa Date: Wed, 7 Feb 2007 10:36:58 -0600 Message-ID: <6D988EC5-4F41-45FA-9FBF-2AC5731D9B27@kernel.crashing.org> References: <989B956029373F45A0B8AF02970818900D4332@zch01exm26.fsl.freescale.net> Mime-Version: 1.0 (Apple Message framework v752.2) Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Content-Transfer-Encoding: 7bit Cc: , , To: Li Yang-r58472 Return-path: Received: from nommos.sslcatacombnetworking.com ([67.18.224.114]:30341 "EHLO nommos.sslcatacombnetworking.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965684AbXBGQuA (ORCPT ); Wed, 7 Feb 2007 11:50:00 -0500 In-Reply-To: <989B956029373F45A0B8AF02970818900D4332@zch01exm26.fsl.freescale.net> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Feb 7, 2007, at 3:34 AM, Li Yang-r58472 wrote: >> On Feb 6, 2007, at 5:31 AM, Li Yang wrote: >> >>> Get rid of private immrbar_virt_to_phys() routine and >>> use generic iopa(). >> >> Nack. iopa() isn't that generic, shouldn't we really be using the dma >> mapping API here? > > Do you mean the dma_map_single()? dma_map_single can map memory space > correctly, but I don't think it can handle ioremap-ed space. What are you mapping? It looks like buffer descriptor rings. Are they being kept in QE sram? If so that I think you can treat it as memory. (I believe the SRAM behaves like memory, is cache-coherent, etc). - k From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from nommos.sslcatacombnetworking.com (nommos.sslcatacombnetworking.com [67.18.224.114]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id 8FAF6DDEC6 for ; Thu, 8 Feb 2007 03:50:03 +1100 (EST) In-Reply-To: <989B956029373F45A0B8AF02970818900D4332@zch01exm26.fsl.freescale.net> References: <989B956029373F45A0B8AF02970818900D4332@zch01exm26.fsl.freescale.net> Mime-Version: 1.0 (Apple Message framework v752.2) Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Message-Id: <6D988EC5-4F41-45FA-9FBF-2AC5731D9B27@kernel.crashing.org> From: Kumar Gala Subject: Re: [PATCH 1/4] ucc_geth: Change private immrbar_virt_to_phys to generic iopa Date: Wed, 7 Feb 2007 10:36:58 -0600 To: Li Yang-r58472 Cc: netdev@vger.kernel.org, jeff@garzik.org, linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Feb 7, 2007, at 3:34 AM, Li Yang-r58472 wrote: >> On Feb 6, 2007, at 5:31 AM, Li Yang wrote: >> >>> Get rid of private immrbar_virt_to_phys() routine and >>> use generic iopa(). >> >> Nack. iopa() isn't that generic, shouldn't we really be using the dma >> mapping API here? > > Do you mean the dma_map_single()? dma_map_single can map memory space > correctly, but I don't think it can handle ioremap-ed space. What are you mapping? It looks like buffer descriptor rings. Are they being kept in QE sram? If so that I think you can treat it as memory. (I believe the SRAM behaves like memory, is cache-coherent, etc). - k