From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hiroshi Doyu Subject: Re: [PATCH v2 1/3] ARM: tegra: Add AHB driver Date: Thu, 26 Apr 2012 08:49:44 +0300 Message-ID: <20120426084944.21e7aa1c3944c906742967a2@nvidia.com> References: <1335269116-9578-1-git-send-email-hdoyu@nvidia.com> <20120425083747.466f5c98330af8964d980b8c@nvidia.com> <20120425074639.GB3423@arwen.pp.htv.fi> <201204251215.22889.arnd@arndb.de> <4F981F6C.2050807@wwwdotorg.org> Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4F981F6C.2050807-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Arnd Bergmann , "balbi-l0cyMroinI0@public.gmane.org" , Russell King - ARM Linux , Stephen Warren Cc: "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Colin Cross , Olof Johansson , Grant Likely , Rob Herring , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org" List-Id: devicetree@vger.kernel.org On Wed, 25 Apr 2012 17:59:40 +0200 Stephen Warren wrote: > On 04/25/2012 06:15 AM, Arnd Bergmann wrote: > > On Wednesday 25 April 2012, Felipe Balbi wrote: > ... > >>> Can this driver be located under "drivers/misc"? Or is there any better place? > >> > >> maybe drivers/platform/arm/ ?? > > > > I really wouldn't want to add that directory: It has the risk of letting > > people add random crap there that may or may not be related to ARM (the > > company) and/or ARM (the architecture). > > > > I think it could go into drivers/amba/ along with the primecell bus driver. > > The two drivers are for two different aspects of the AMBA spec and don't > > actually depend on one another as far as I can tell, but it's at least > > a fitting name, and it doesn't depend on the ARM architecture, which is > > important because the driver could be used on other architectures that > > are connected to an AHB bus. > > Hiroshi, is this driver for something (registers/features) that AMBA > actually specifies? AHB might be part of AMBA (I'm not familiar enough > to know), but I don't think this aspect of Tegra's AHB bus is part of > any core AHB/AMBA specification, rather than being some Tegra-specific > control over the bus (given that the registers and bits correspond to > Tegra-specific devices on the bus). Agree. Taking a look at AHB spec, this tegra-ahb part is a bit beyond that spec from S/W POV. If there's other similiar AHB drivers from othere SoC, we may be able to generalize them, but at the moment, it's hard to imagine how much/little part is common for similar AHB drivers, like registers/bit definitions. Most of the part may depends on SoC/Tegra. > I'm not really convinced that low-level platform-specific drivers like > this shouldn't be in the arch/arm/mach-* directories. So I think that keeping this kind of drivers under "arch/arm/mach-*" or "drivers/amba" as 'tegra'-ahb.c name. If similier drivers comes, then, what about thinking the generalization again? Either way would be ok for me.