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 F3A69DDE42 for ; Thu, 8 Feb 2007 18:43:50 +1100 (EST) In-Reply-To: <989B956029373F45A0B8AF02970818900D441A@zch01exm26.fsl.freescale.net> References: <989B956029373F45A0B8AF02970818900D441A@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: <82ABE776-0C94-4FAE-BD24-071988842EA9@kernel.crashing.org> From: Kumar Gala Subject: Re: [PATCH 1/4] ucc_geth: Change private immrbar_virt_to_phys to generic iopa Date: Thu, 8 Feb 2007 01:41:51 -0600 To: "Li Yang-r58472" Cc: netdev@vger.kernel.org, Tabi Timur-B04825 , linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Feb 8, 2007, at 1:36 AM, Li Yang-r58472 wrote: >> -----Original Message----- >> From: Kumar Gala [mailto:galak@kernel.crashing.org] >> Sent: Thursday, February 08, 2007 3:16 PM >> To: Li Yang-r58472 >> Cc: Tabi Timur-B04825; netdev@vger.kernel.org; linuxppc- >> dev@ozlabs.org >> Subject: Re: [PATCH 1/4] ucc_geth: Change private >> immrbar_virt_to_phys > to generic >> iopa >> >> >> On Feb 8, 2007, at 1:06 AM, Li Yang-r58472 wrote: >> >>>>> MURAM is a mmio region so it don't share the characteristic of > main >>>>> memory that phy_addr = virt_addr - PAGE_OFFSET. While they can >>>>> both be >>>>> mapped through page table using iopa(). >>>> >>>> Right, so when do you know if you'll be using MURAM or normal >>>> memory? Why not just keep around a token that is the physical >>>> address at the point you make the decision of MURAM vs normal > memory. >>> >>> Yes, that can be a way. But as the virt to phy mapping is only used >>> once, it's nothing bad to do it this way. >> >> The problem as I stated before with using iopa() is that its not >> supported across platforms. > > Yes, it is only for PPC32. But we don't have another API to do > it. How > about make it more generic to add PPC64 version? Why do you need another API to do this, you already have the information you want, its just a matter of you keeping track of it. - k