rockchip: back-to-bootrom: replace assembly-implementation with C-code

[people/ms/u-boot.git] / arch / arm / include / asm / arch-rockchip / bootrom.h

/*
 * (C) Copyright 2017 Heiko Stuebner <heiko@sntech.de>
 * (C) Copyright 2017 Theobroma Systems Design und Consulting GmbH
 *
 * SPDX-License-Identifier:	GPL-2.0
 */

#ifndef _ASM_ARCH_BOOTROM_H
#define _ASM_ARCH_BOOTROM_H

/*
 * Saved Stack pointer address.
 * Access might be needed in some special cases.
 */
extern u32 SAVE_SP_ADDR;

/**
 * back_to_bootrom() - return to bootrom (for TPL/SPL), passing a
 *                     result code
 *
 * Transfer control back to the Rockchip BROM, restoring necessary
 * register context and passing a command/result code to the BROM
 * to instruct its next actions (e.g. continue boot sequence, enter
 * download mode, ...).
 *
 * This function does not return.
 */
enum rockchip_bootrom_cmd {
	/*
	 * These can not start at 0, as 0 has a special meaning
	 * for setjmp().
	 */

	BROM_BOOT_NEXTSTAGE = 1,  /* continue boot-sequence */
	BROM_BOOT_ENTER_DNL,      /* have BROM enter download-mode */
};

void back_to_bootrom(void);

/**
 * Boot-device identifiers as used by the BROM
 */
enum {
	BROM_BOOTSOURCE_NAND = 1,
	BROM_BOOTSOURCE_EMMC = 2,
	BROM_BOOTSOURCE_SPINOR = 3,
	BROM_BOOTSOURCE_SPINAND = 4,
	BROM_BOOTSOURCE_SD = 5,
	BROM_BOOTSOURCE_USB = 10,
	BROM_LAST_BOOTSOURCE = BROM_BOOTSOURCE_USB
};

/**
 * Locations of the boot-device identifier in SRAM
 */
#define RK3399_BROM_BOOTSOURCE_ID_ADDR   0xff8c0010

#endif