[PATCH] arm: socfpga: fix fetching cpu1start_addr for system with > 2GB of ram

[Russell King - ARM Linux]

On Wed, Oct 01, 2014 at 06:02:14AM -0500, dinguyen at opensource.altera.com wrote:
> From: Dinh Nguyen <dinguyen at opensource.altera.com>
> 
> When CPU1 is brought out of reset, it's MMU is not turned yet, so it will only
> be able to use physical addresses. For systems with 1GB or less, clearing
> 0x40000000 will work just fine. However for systems with 2GB or more, we
> need to clear at least 0x80000000.
> 
> Essentially, the bic instruction is converting the cpu1start_addr from a
> virtual to a physical address. We should be using bic 0xf0000000 for all
> systems.

Err.  Why not do the job properly rather than create this type of hack?
This is not a fast path, so it's really not required to code it for an
absolute minimum number of cycles.  So...

	adr	r0, 1f		@ physical address of '1'
	ldmia	r0, {r1, r2}	@ load virtual address of '1' and 'cpu1start_addr'
	sub	r0, r0, r1	@ offset between virtual and physical
	ldr	r2, [r2, r0]	@ load *cpu1start_addr
	bx	r2
...
	.align
1:	.long	.
	.long	cpu1start_addr

will fix it properly.

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