N900 v3.19-rc5 arm atags_to_fdt.c is broken

[Pali Rohár]

On Friday 23 January 2015 22:39:55 Pali Rohár wrote:
> Hello,
> 
> when I boot zImage with appended DT n900 in qemu
> fdt_open_into() function called from file
> arch/arm/boot/compressed/atags_to_fdt.c (in function
> atags_to_fdt) always returns -FDT_ERR_NOSPACE.
> 
> It means that all ATAGS (including cmdline arguments) passed
> by bootloader are ignored.
> 
> On real n900 device I see that booted DT version also ignore
> cmdline arguments from bootloader. I cannot debug decompress
> code on real device, but I think it is same problem as in
> qemu.

Looks like this quick patch is fixing above problem:

diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S
index 68be901..4a7d75b 100644
--- a/arch/arm/boot/compressed/head.S
+++ b/arch/arm/boot/compressed/head.S
@@ -268,7 +268,7 @@ restart:	adr	r0, LC0
 		 * area.  No GOT fixup has occurred yet, but none of the
 		 * code we're about to call uses any global variable.
 		*/
-		add	sp, sp, #0x10000
+		add	sp, sp, #0x20000
 		stmfd	sp!, {r0-r3, ip, lr}
 		mov	r0, r8
 		mov	r1, r6
@@ -289,7 +289,7 @@ restart:	adr	r0, LC0
 		bleq	atags_to_fdt
 
 		ldmfd	sp!, {r0-r3, ip, lr}
-		sub	sp, sp, #0x10000
+		sub	sp, sp, #0x20000
 #endif
 
 		mov	r8, r6			@ use the appended device tree


-- 
Pali Rohár
pali.rohar at gmail.com
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