From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 13 Aug 2002 08:34:03 -0700 From: Matt Porter To: linuxppc-embedded@lists.linuxppc.org Subject: Re: First steps to OCP device model integration Message-ID: <20020813083403.A30884@home.com> References: <20020809042605.GC23642@zax> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20020809042605.GC23642@zax>; from david@gibson.dropbear.id.au on Fri, Aug 09, 2002 at 02:26:05PM +1000 Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: On Fri, Aug 09, 2002 at 02:26:05PM +1000, David Gibson wrote: > > THe patch below implements the first steps in transitioning the > handling of 4xx OCP devices to the unfied device model (in 2.5). So > far the code just registers an ocp bus and registers each device > described in core_ocp on that bus. The next step is to convert the > actual device drivers so that that they register with the unified > driver tree rather than through the old ocp_register() mechanism. Hi David, I don't have any concerns about your patch as a starting point, but I'd like to talk about where we are going with driverfs integration of proprietary on-chip buses (4xx and other SoCs). This "first steps" patch shows you registering OCP as a bus with a name of "Onchip Peripheral Bus". This seems to trivialize the bus hierarchy on 4xx and part of the point of driverfs is to see where devices are located in the physical bus structure (since management of them may vary based on their location). I would expect to see "PLB", "OPB", and "ExtBus" registered for 4xx for correctness. They may all use the same bus ops in a reference board implementation (not making use of the EBC in most cases), but somebody could have some FPGA-based peripherals hanging from the EBC which require board-specific PM ops and thus it would be desirable to see and manage at least the External Bus separately in driverfs. Regards, -- Matt Porter porter@cox.net This is Linux Country. On a quiet night, you can hear Windows reboot. ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/