From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benoit Cousson Subject: Re: [PATCH 5/9] ARM: dts: Add GPMC node for OMAP2, OMAP4 and OMAP5 Date: Thu, 14 Mar 2013 16:45:02 +0100 Message-ID: <5141F07E.3030501@ti.com> References: <1362763654-9660-1-git-send-email-jon-hunter@ti.com> <1362763654-9660-6-git-send-email-jon-hunter@ti.com> <513A5B23.5070302@ti.com> <513E1ADC.6030208@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from bear.ext.ti.com ([192.94.94.41]:43045 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755850Ab3CNPpW (ORCPT ); Thu, 14 Mar 2013 11:45:22 -0400 In-Reply-To: <513E1ADC.6030208@ti.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Jon Hunter Cc: Ezequiel Garcia , Javier Martinez Canillas , Tony Lindgren , device-tree , linux-omap , linux-arm On 03/11/2013 06:56 PM, Jon Hunter wrote: > > On 03/09/2013 06:42 AM, Ezequiel Garcia wrote: >> On Fri, Mar 8, 2013 at 10:25 PM, Javier Martinez Canillas >> wrote: >>> On Fri, Mar 8, 2013 at 10:41 PM, Jon Hunter wrote: >>>> >>>> Yes you are correct. In general, I have been trying to stay some-what >>>> consistent with what hwmod was doing as this was being auto-generated by >>>> some hardware design specs and I believe they wanted to eventually get >>>> to the point where DT files would be auto-generated too for OMAP. >>>> Furthermore my understanding is that the smallest page that can be >>>> mapped by the kernel for ARM is 4kB. So if you declare it as 0x2d0 or >>>> 0x1000 it will map a 4kB page (I could be wrong here). >>>> >>>> I don't have any strong feelings here but will do what the consensus >>>> prefers. >>>> >>> >>> Yes, you are right here. >>> >>> I forget that ioremap() does a page-aligned mapping and since the >>> minimum page size for ARM is 4KB as you said, there is no difference >>> between using 0x2d0 and 0x1000. Sorry for the noise. >>> >> >> Certainly, I don't have strong feelings about this. >> FWIW, mvebu maintainers imposes a "minimal" address space request >> policy. >> >> On the other side, it seems to me we shouldn't look at internal kernel >> implementation (i.e. ioremap page-alignment) to make this decision. > > I agree with that. I am not sure if Tony/Benoit have any comments on > what they would like to do here to be consistent for the omap bindings. Yes, I full agree with that as well. The size should be purely HW related. So we should not take any assumption about the page size / alignment. Regards, Benoit