[U-Boot] CONFIG_SYS_LINUX_LOWMEM_MAX_SIZE

[anup behare]

Hi  Stefan,


My intention was only to remove this warning.

My Linux is booting correctly and it is not causing any trouble but I
observed "WARNING: adjusting available memory to 0x30000000" on u-boot
console.

I have couple of question here with 768MB:

1. Is that mean u-boot will use only 768MB DDR?

2. What about kernel will it use complete DDR or will work with 768MB only?

3. Means we can’t remove this warning and this warning will come for DDR
more than 768MB?



~Anup


On Tue, May 18, 2010 at 1:37 PM, Stefan Roese <sr at denx.de> wrote:

> Hi Anup,
>
> On Tuesday 18 May 2010 09:03:25 anup behare wrote:
> > We are using taishan based board having 1GB DDR.
> > In u-boot code we found that CONFIG_SYS_LINUX_LOWMEM_MAX_SIZE is set to
> > 768MB hence "if (size < bootm_size)" condition becomes true and u-boot
> > throw "WARNING: adjusting available memory to 0x30000000" message on
> > console.
> >
> > Let me know will it possible to set CONFIG_SYS_LINUX_LOWMEM_MAX_SIZE to
> 1GB
> > or is there any fix for above warning message?
>
> Linux "lowmem" size is 768MB for PowerPC. Loading at a higher address
> results
> in a non-booting Linux kernel. So this warning makes sense and it's not
> possible to load to 1GB.
>
> Why do you want to change this? Does this cause you any troubles? Is Linux
> not
> booting correctly? I don't see what you would "gain" by loading to 1GB.
>
> Cheers,
> Stefan
>
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