Re: [PATCH] Revert "ARM: Use armlinux_bootparams address for DTB"

[Alexander Shiyan]

> On Wed, Aug 07, 2013 at 01:55:42PM +0400, Alexander Shiyan wrote:
> > > This patch placed the flattened devicetree to armlinux_bootparams.
> > > armlinux_bootparams normally is at SDRAM_START + 0x100. The kernels
> > > initial page tables are normally at SDRAM_START + 0x4000, so the
> > > flattened devicetree gets overwritten once it exceeds 0x3f00 bytes
> > > which is quite common.
> > > 
> > > Revert this patch for now once a better solution can be found
> > 
> > In such a case, tree may be placed immediately after the kernel?
> > It can also serve as an automatic option "ARM_APPENDED_DTB".
> 
> That won't work either, since the DTB will be overwritten by the kernel
> decompressor.

arch/arm/Kconfig:
...
config ARM_APPENDED_DTB
	bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
	depends on OF && !ZBOOT_ROM
	help
	  With this option, the boot code will look for a device tree binary
	  (DTB) appended to zImage
	  (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
...

So, DTB is placed immediately after the kernel.

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