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	Relocation code based on a patch by Scott Wood, which is: Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: David Feng <fenghua@phytium.com.cn>
		
			
				
	
	
		
			47 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			47 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| U-boot for arm64
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| 
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| Summary
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| =======
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| No hardware platform of arm64 is available now. The u-boot is
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| simulated on Foundation Model and Fast Model for ARMv8.
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| 
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| Notes
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| =====
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| 
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| 1. Currenly, u-boot run at the highest exception level processor
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|    supported and jump to EL2 or optionally EL1 before enter OS.
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| 
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| 2. U-boot for arm64 is compiled with AArch64-gcc. AArch64-gcc
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|    use rela relocation format, a tool(tools/relocate-rela) by Scott Wood
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|    is used to encode the initial addend of rela to u-boot.bin. After running,
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|    the u-boot will be relocated to destination again.
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| 
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| 3. Fdt should be placed at a 2-megabyte boundary and within the first 512
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|    megabytes from the start of the kernel image. So, fdt_high should be
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|    defined specially.
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|    Please reference linux/Documentation/arm64/booting.txt for detail.
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| 
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| 4. Spin-table is used to wake up secondary processors. One location
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|    (or per processor location) is defined to hold the kernel entry point
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|    for secondary processors. It must be ensured that the location is
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|    accessible and zero immediately after secondary processor
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|    enter slave_cpu branch execution in start.S. The location address
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|    is encoded in cpu node of DTS. Linux kernel store the entry point
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|    of secondary processors to it and send event to wakeup secondary
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|    processors.
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|    Please reference linux/Documentation/arm64/booting.txt for detail.
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| 
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| 5. Generic board is supported.
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| 
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| 6. CONFIG_ARM64 instead of CONFIG_ARMV8 is used to distinguish aarch64 and
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|    aarch32 specific codes.
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| 
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| Contributor
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| ===========
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|    Tom Rini       <trini@ti.com>
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|    Scott Wood     <scottwood@freescale.com>
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|    York Sun       <yorksun@freescale.com>
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|    Simon Glass    <sjg@chromium.org>
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|    Sharma Bhupesh <bhupesh.sharma@freescale.com>
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|    Rob Herring    <robherring2@gmail.com>
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