[U-Boot] [PATCH 1/5] mx6sabre{auto, sd}: Change FDT loading address to avoid overlaping

[Otavio Salvador]

On Mon, Nov 4, 2013 at 1:27 AM, Hui Liu <r64343 at freescale.com> wrote:
>> -----Original Message-----
>> From: Fabio Estevam [mailto:festevam at gmail.com]
>> Sent: Friday, November 01, 2013 10:19 PM
>> To: Otavio Salvador
>> Cc: U-Boot Mailing List; Estevam Fabio-R49496; Liu Hui-R64343
>> Subject: Re: [U-Boot] [PATCH 1/5] mx6sabre{auto, sd}: Change FDT loading
>> address to avoid overlaping
>>
>> On Fri, Nov 1, 2013 at 11:00 AM, Otavio Salvador <otavio at ossystems.com.br>
>> wrote:
>>
>> > I am quoting the original commit change:
>> >
>> >     ENGR00268032 config/sabre_common: change the fdt_addr to a high
>> > address
>> >
>> >     current the fdt_addr is just 16MB offset from the ddr base address,
>> which
>> >     will cause the dtb will be overritten by linux kernel(include .bss
>> section)
>> >     if the linux kernel is bigger than 16MB, which cause
>> setup_machine_fdt
>> >     failed and thus kernel failed to boot.
>>
>> What is the size of the FSL 3.10 kernel?
>>
>> I still do not understand the fix after reading the commit log you
>> pointed to.
>>
>> Adding Jason, in case he could help clarifying it.
>
> This is due to that the dtb will be overridden by the Linux kernel if the dtb is just 16MB offset
> While Linux kernel is big enough. We have found this issue when Linux kernel image is bigger since
> the decompressed kernel will also start from the beginning of the DDR.
>
> To enlarge the dtb offset is just one workaround for this kernel common issue.
>
> The ideal solution is to fix it in Linux kernel but don't have much time to do it.

What is the final decision on this? I have the same change for many
boards which are/will be supported by 3.10.

-- 
Otavio Salvador                             O.S. Systems
http://www.ossystems.com.br        http://code.ossystems.com.br
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