xref: /rk3399_ARM-atf/bl2/aarch64/bl2_entrypoint.S (revision c948f77136c42a92d0bb660543a3600c36dcf7f1)
1/*
2 * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7#include <arch.h>
8#include <asm_macros.S>
9#include <common/bl_common.h>
10
11
12	.globl	bl2_entrypoint
13
14
15
16func bl2_entrypoint
17	/*---------------------------------------------
18	 * Save arguments x0 - x3 from BL1 for future
19	 * use.
20	 * ---------------------------------------------
21	 */
22	mov	x20, x0
23	mov	x21, x1
24	mov	x22, x2
25	mov	x23, x3
26
27	/* ---------------------------------------------
28	 * Set the exception vector to something sane.
29	 * ---------------------------------------------
30	 */
31	adr	x0, early_exceptions
32	msr	vbar_el1, x0
33	isb
34
35	/* ---------------------------------------------
36	 * Enable the SError interrupt now that the
37	 * exception vectors have been setup.
38	 * ---------------------------------------------
39	 */
40	msr	daifclr, #DAIF_ABT_BIT
41
42	/* ---------------------------------------------
43	 * Enable the instruction cache, stack pointer
44	 * and data access alignment checks
45	 * ---------------------------------------------
46	 */
47	mov	x1, #(SCTLR_I_BIT | SCTLR_A_BIT | SCTLR_SA_BIT)
48	mrs	x0, sctlr_el1
49	orr	x0, x0, x1
50	msr	sctlr_el1, x0
51	isb
52
53	/* ---------------------------------------------
54	 * Invalidate the RW memory used by the BL2
55	 * image. This includes the data and NOBITS
56	 * sections. This is done to safeguard against
57	 * possible corruption of this memory by dirty
58	 * cache lines in a system cache as a result of
59	 * use by an earlier boot loader stage.
60	 * ---------------------------------------------
61	 */
62	adr	x0, __RW_START__
63	adr	x1, __RW_END__
64	sub	x1, x1, x0
65	bl	inv_dcache_range
66
67	/* ---------------------------------------------
68	 * Zero out NOBITS sections. There are 2 of them:
69	 *   - the .bss section;
70	 *   - the coherent memory section.
71	 * ---------------------------------------------
72	 */
73	adrp	x0, __BSS_START__
74	add	x0, x0, :lo12:__BSS_START__
75	adrp	x1, __BSS_END__
76	add	x1, x1, :lo12:__BSS_END__
77	sub	x1, x1, x0
78	bl	zeromem
79
80#if USE_COHERENT_MEM
81	adrp	x0, __COHERENT_RAM_START__
82	add	x0, x0, :lo12:__COHERENT_RAM_START__
83	adrp	x1, __COHERENT_RAM_END_UNALIGNED__
84	add	x1, x1, :lo12:__COHERENT_RAM_END_UNALIGNED__
85	sub	x1, x1, x0
86	bl	zeromem
87#endif
88
89	/* --------------------------------------------
90	 * Allocate a stack whose memory will be marked
91	 * as Normal-IS-WBWA when the MMU is enabled.
92	 * There is no risk of reading stale stack
93	 * memory after enabling the MMU as only the
94	 * primary cpu is running at the moment.
95	 * --------------------------------------------
96	 */
97	bl	plat_set_my_stack
98
99	/* ---------------------------------------------
100	 * Initialize the stack protector canary before
101	 * any C code is called.
102	 * ---------------------------------------------
103	 */
104#if STACK_PROTECTOR_ENABLED
105	bl	update_stack_protector_canary
106#endif
107
108	/* ---------------------------------------------
109	 * Perform early platform setup & platform
110	 * specific early arch. setup e.g. mmu setup
111	 * ---------------------------------------------
112	 */
113	mov	x0, x20
114	mov	x1, x21
115	mov	x2, x22
116	mov	x3, x23
117	bl	bl2_early_platform_setup2
118
119	bl	bl2_plat_arch_setup
120
121	/* ---------------------------------------------
122	 * Jump to main function.
123	 * ---------------------------------------------
124	 */
125	bl	bl2_main
126
127	/* ---------------------------------------------
128	 * Should never reach this point.
129	 * ---------------------------------------------
130	 */
131	no_ret	plat_panic_handler
132
133endfunc bl2_entrypoint
134