From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id B0603474C1 for ; Fri, 12 Dec 2008 03:14:10 +1100 (EST) Message-Id: <41706FC0-B740-42C0-BA2B-B9E4B5839477@kernel.crashing.org> From: Kumar Gala To: "maillist.kernel" In-Reply-To: <200812112004118902765@gmail.com> Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Mime-Version: 1.0 (Apple Message framework v929.2) Subject: Re: How to support 3GB pci address? Date: Thu, 11 Dec 2008 10:13:57 -0600 References: <200812112004118902765@gmail.com> Cc: linuxppc-dev List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Dec 11, 2008, at 6:04 AM, maillist.kernel wrote: > Hi, we want to design a system using mpc8548, and linking with an > idt 16 ports PCIE switch. > In the system, the total PCI address needed is about 3GB, so I want > to know how to support it in linux. mpc8548 has 36-bit real address, > and can support 32GB PCIE address space, but in linux, there is only > 1GB kernel space, how to map the 3GB pci address to kernel? Is the > 36-bit real address only used to support large memory(>4GB) for muti- > threads? > > Any suggestions please would be much appreciated! > > Thanks in advance for your help The 36-bit support is current (in tree) in complete. Work is in progress to add swiotlb support to PPC which will generically enable what you want to accomplish. - k