[U-Boot] [PATCH] mx6sabre_common: Allow booting a FSL 3.10 kernel

[Otavio Salvador]

On Mon, Nov 25, 2013 at 1:54 PM, Fabio Estevam
<fabio.estevam at freescale.com> wrote:
> Currently the booting of a 3.10 kernel fails, as explained by Jason Liu [1]:
>
> "Let me explain it:
> since we defined the fdt_high=0xffffffff at include/configs/mx6qsabre_common.h,
> which means we disable the fdt re-allocation, which you can see when boot up:
>
> ## Flattened Device Tree blob at 11000000
>    Booting using the fdt blob at 0x11000000
>    Using Device Tree in place at 11000000, end 1800e37e
>
> The FDT blob will be placed at DDR physical addr: 0x11000000. When Linux kernel
> Boot up, it will decompress the compressed kernel image and place the
> decompressed kernel image at the low end of the DDR memory and start running
> from it. If the decompressed kernel image is bigger for example than 16M, it may
> over written the fdt blob which u-boot loaded to the DDR memory @0x11000000 with
> fdt_addr=0x11000000.
>
> o expand the fdt_addr from 0x11000000 to 0x18000000, which can avoid the
> override, since we will not likely have one kernel image larger than 128MB.
>
> The other solution is to enable the FDT blob re-allocation by remove the
> fdt_high=0xffffffff"
>
> Use the second approach to enable the boot of a FSL 3.10 kernel.
>
> [1] http://marc.info/?l=u-boot&m=138519609402384&w=2
>
> Signed-off-by: Fabio Estevam <fabio.estevam at freescale.com>

My patch changed the load address for the device tree blog, as
explained by Liu, it avoids an extra copy which may impact in boot
speed.

-- 
Otavio Salvador                             O.S. Systems
http://www.ossystems.com.br        http://code.ossystems.com.br
Mobile: +55 (53) 9981-7854            Mobile: +1 (347) 903-9750