From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olof Johansson Subject: Re: [PATCH 1/5] arm/dt: tegra: Remove /memreserve/ from device-tree files Date: Wed, 7 Dec 2011 16:22:19 -0800 Message-ID: <20111208002219.GL12945@quad.lixom.net> References: <1321911851-10091-1-git-send-email-swarren@nvidia.com> <2308525.meomQFtUnY@ax5200p> <74CDBE0F657A3D45AFBB94109FB122FF174F08C3BC@HQMAIL01.nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <74CDBE0F657A3D45AFBB94109FB122FF174F08C3BC-C7FfzLzN0UxDw2glCA4ptUEOCMrvLtNR@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Stephen Warren Cc: Marc Dietrich , Colin Cross , Peter De Schrijver , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org" List-Id: linux-tegra@vger.kernel.org On Tue, Nov 22, 2011 at 08:25:03AM -0800, Stephen Warren wrote: > Marc Dietrich wrote at Tuesday, November 22, 2011 3:42 AM: > > On Monday 21 November 2011 14:44:07 Stephen Warren wrote: > > > There are no drivers in the kernel at present which can make use of the > > > memory reserved by /memreserve/, so there is no point reserving it. Remove > > > /memreserve/ to allow the user more memory. It's also unclear whether any > > > future driver would actually require /memreserve/, or allocate memory > > > through some other mechanism. > > > > while this gives 512 MB of usable memory on my AC100, it causes some funny > > pictures on the screen ;-) I guess our bootloader (fastboot) already setups > > the frambuffer there (and enables the backlight). I guess it shouldn't be > > harmful as nothing else writes to this memory area. Otherwise you may add that > > the bootloader (or the kernel cmdline supplied by the bootloader) is now > > responsible for the reservation to the description. > > Ah yes, I guess that would happen. I'm only testing with mainline U-Boot... > > I'd suggest this is acceptable fallout for now; I don't believe it will > cause any active problems, and as you say, you can get the bootloader to > set a command-line that excludes the frame-buffer if you want to solve > this. Do you agree? Agreed. It would make more sense to teach u-boot to reserve the memory. -Olof