xref: /openbmc/u-boot/arch/arm/cpu/armv8/transition.S (revision 1a68faac)
1/* SPDX-License-Identifier: GPL-2.0+ */
2/*
3 * (C) Copyright 2013
4 * David Feng <fenghua@phytium.com.cn>
5 */
6
7#include <asm-offsets.h>
8#include <config.h>
9#include <linux/linkage.h>
10#include <asm/macro.h>
11
12.pushsection .text.armv8_switch_to_el2, "ax"
13ENTRY(armv8_switch_to_el2)
14	switch_el x6, 1f, 0f, 0f
150:
16	cmp x5, #ES_TO_AARCH64
17	b.eq 2f
18	/*
19	 * When loading 32-bit kernel, it will jump
20	 * to secure firmware again, and never return.
21	 */
22	bl armv8_el2_to_aarch32
232:
24	/*
25	 * x4 is kernel entry point or switch_to_el1
26	 * if CONFIG_ARMV8_SWITCH_TO_EL1 is defined.
27         * When running in EL2 now, jump to the
28	 * address saved in x4.
29	 */
30	br x4
311:	armv8_switch_to_el2_m x4, x5, x6
32ENDPROC(armv8_switch_to_el2)
33.popsection
34
35.pushsection .text.armv8_switch_to_el1, "ax"
36ENTRY(armv8_switch_to_el1)
37	switch_el x6, 0f, 1f, 0f
380:
39	/* x4 is kernel entry point. When running in EL1
40	 * now, jump to the address saved in x4.
41	 */
42	br x4
431:	armv8_switch_to_el1_m x4, x5, x6
44ENDPROC(armv8_switch_to_el1)
45.popsection
46
47.pushsection .text.armv8_el2_to_aarch32, "ax"
48WEAK(armv8_el2_to_aarch32)
49	ret
50ENDPROC(armv8_el2_to_aarch32)
51.popsection
52