u-boot-brain/arch/arm/include/asm/arch-rockchip/boot0.h

/*
 * Copyright 2017 Theobroma Systems Design und Consulting GmbH
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

/*
 * Execution starts on the instruction following this 4-byte header
 * (containing the magic 'RK33').
 *
 * To make life easier for everyone, we build the SPL binary with
 * space for this 4-byte header already included in the binary.
 */

#ifdef CONFIG_SPL_BUILD
	.space 0x4         /* space for the 'RK33' */
#endif
	b reset
rockchip: spl: RK3399: use boot0 hook to create space for SPL magic The SPL binary needs to be prefixed with the boot magic ('RK33' for the RK3399) on the Rockchip platform and starts execution of the instruction word following immediately after this boot magic. This poses a challenge for AArch64 (ARMv8) binaries, as the .text section would need to start on the odd address, violating natural alignment (and potentially triggering a fault for any code that tries to access 64bit values embedded in the .text section). A quick and easy fix is to have the .text section include the 'RK33' magic and pad it with a boot0 hook to insert 4 bytes of padding at the start of the section (with the intention of having mkimage overwrite this padding with the appropriate boot magic). This avoids having to modify the linker scripts or more complex logic in mkimage. X-AffectedPlatforms: RK3399-Q7 Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com> Tested-by: Klaus Goger <klaus.goger@theobroma-systems.com> 2017-03-15 20:08:44 +09:00			`/*`
			`* Copyright 2017 Theobroma Systems Design und Consulting GmbH`
			`*`
			`* SPDX-License-Identifier: GPL-2.0+`
			`*/`

			`/*`
			`* Execution starts on the instruction following this 4-byte header`
			`* (containing the magic 'RK33').`
			`*`
			`* To make life easier for everyone, we build the SPL binary with`
			`* space for this 4-byte header already included in the binary.`
			`*/`

			`#ifdef CONFIG_SPL_BUILD`
			`.space 0x4 /* space for the 'RK33' */`
			`#endif`
			`b reset`