xref: /openbmc/u-boot/arch/arm/cpu/armv8/transition.S (revision cf0bcd7d)
1/*
2 * (C) Copyright 2013
3 * David Feng <fenghua@phytium.com.cn>
4 *
5 * SPDX-License-Identifier:	GPL-2.0+
6 */
7
8#include <asm-offsets.h>
9#include <config.h>
10#include <linux/linkage.h>
11#include <asm/macro.h>
12
13.pushsection .text.armv8_switch_to_el2, "ax"
14ENTRY(armv8_switch_to_el2)
15	switch_el x6, 1f, 0f, 0f
160:
17	cmp x5, #ES_TO_AARCH64
18	b.eq 2f
19	/*
20	 * When loading 32-bit kernel, it will jump
21	 * to secure firmware again, and never return.
22	 */
23	bl armv8_el2_to_aarch32
242:
25	/*
26	 * x4 is kernel entry point or switch_to_el1
27	 * if CONFIG_ARMV8_SWITCH_TO_EL1 is defined.
28         * When running in EL2 now, jump to the
29	 * address saved in x4.
30	 */
31	br x4
321:	armv8_switch_to_el2_m x4, x5, x6
33ENDPROC(armv8_switch_to_el2)
34.popsection
35
36.pushsection .text.armv8_switch_to_el1, "ax"
37ENTRY(armv8_switch_to_el1)
38	switch_el x6, 0f, 1f, 0f
390:
40	/* x4 is kernel entry point. When running in EL1
41	 * now, jump to the address saved in x4.
42	 */
43	br x4
441:	armv8_switch_to_el1_m x4, x5, x6
45ENDPROC(armv8_switch_to_el1)
46.popsection
47
48.pushsection .text.armv8_el2_to_aarch32, "ax"
49WEAK(armv8_el2_to_aarch32)
50	ret
51ENDPROC(armv8_el2_to_aarch32)
52.popsection
53