From mboxrd@z Thu Jan  1 00:00:00 1970
From: lee.jones@linaro.org (Lee Jones)
Date: Mon, 3 Jun 2013 09:21:17 +0100
Subject: [PATCH 2/2] ARM: ux500: Enable HIGHMEM in the u8540 defconfig
In-Reply-To: <1902994.0Kq6C7Rx1R@wuerfel>
References: <1370010272-25520-1-git-send-email-lee.jones@linaro.org>
 <38058740.G1EqTG95pA@wuerfel> <20130531151850.GC12488@gmail.com>
 <1902994.0Kq6C7Rx1R@wuerfel>
Message-ID: <20130603082117.GD3370@gmail.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Fri, 31 May 2013, Arnd Bergmann wrote:

> On Friday 31 May 2013 16:18:50 Lee Jones wrote:
> > On Fri, 31 May 2013, Arnd Bergmann wrote:
> > 
> > > On Friday 31 May 2013 15:24:32 Lee Jones wrote:
> > > > In order to utilise all of the memory located on ux500 based devices
> > > > we have to enable HIGHMEM. Without it the kernel truncates memory down
> > > > to what's left after the PAGE_OFFSET has been applied, which doesn't
> > > > leave an awful lot, especially if we're running large rootfs' such
> > > > as full Linux desktop distributions or Android.
> > > > 
> > > > Signed-off-by: Lee Jones <lee.jones@linaro.org>
> > > 
> > > How much memory do those devices have? Enabling HIGHMEM is quite expensive.
> > 
> > Another 1GB.
> 
> You mean you have 2GB total or 1.75GB?  You could just use

We have 2GB in total.

> CONFIG_VMSPLIT_2G to an extra GB compared to the default, which
> is what vexpress, imx and s5p already do, but you still have to
> put the vmalloc area in the low 2GB then.

Isn't this for 4GB systems?

-- 
Lee Jones
Linaro ST-Ericsson Landing Team Lead
Linaro.org ? Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog