From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from fed1rmmtao03.cox.net (fed1rmmtao03.cox.net [68.230.241.36]) by ozlabs.org (Postfix) with ESMTP id 076BA67D81 for ; Sun, 24 Jul 2005 00:48:44 +1000 (EST) Date: Sat, 23 Jul 2005 07:48:42 -0700 From: Matt Porter To: Yasushi SHOJI Message-ID: <20050723074842.C5431@cox.net> References: <87hdeuosmq.wl@mail2.atmark-techno.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <87hdeuosmq.wl@mail2.atmark-techno.com>; from yashi@atmark-techno.com on Sun, Jul 17, 2005 at 03:26:21PM +0900 Cc: linuxppc-embedded Subject: Re: ppc_sys.c with platform device model or create opb bus? List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Sun, Jul 17, 2005 at 03:26:21PM +0900, Yasushi SHOJI wrote: > Hi all, > > I've been reading some posts regarding to the transition of OCP to > platform device mode while searching for a good way to implement a > device driver for our fpga base platform. And now I have one question > regarding to ppc_sys.c > > should I use ppc_sys_*() for platform like fpga? > > since I'm working on FPGA base platform, ppc_sys_spec seems to be too > static. that is, IMHO, having static array of device list isn't ideal > for a dynamic system like fpga. > > I feel that the ppc_sys_spec is for SoC, which doesn't dynamically > change the peripherals it has. otoh, fpga based platform can have > arbitrary number of devices if you configured so. > > I usually implement a device with PLB or OPB. for those bus, should I > use platform device model or create new buses for each? Use the platform model. When you run into a case that can't be handled properly then the platform model should be expanded to handle it. If you instantiate a "platform device" by configuring the FPGA from userspace then that's a hotplug event. The platform model should be extended to handle hotplug for these kind of cases since they are pretty common. -Matt