xref: /rk3399_ARM-atf/bl2u/aarch32/bl2u_entrypoint.S (revision 1552df5d25944b2bddf42e96acbadca18b3c7c95)
1/*
2 * Copyright (c) 2016, 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	.globl	bl2u_vector_table
12	.globl	bl2u_entrypoint
13
14
15vector_base bl2u_vector_table
16	b	bl2u_entrypoint
17	b	report_exception	/* Undef */
18	b	report_exception	/* SVC call */
19	b	report_exception	/* Prefetch abort */
20	b	report_exception	/* Data abort */
21	b	report_exception	/* Reserved */
22	b	report_exception	/* IRQ */
23	b	report_exception	/* FIQ */
24
25
26func bl2u_entrypoint
27	/*---------------------------------------------
28	 * Save from r1 the extents of the trusted ram
29	 * available to BL2U for future use.
30	 * r0 is not currently used.
31	 * ---------------------------------------------
32	 */
33	mov	r11, r1
34	mov	r10, r2
35
36	/* ---------------------------------------------
37	 * Set the exception vector to something sane.
38	 * ---------------------------------------------
39	 */
40	ldr	r0, =bl2u_vector_table
41	stcopr	r0, VBAR
42	isb
43
44	/* -----------------------------------------------------
45	 * Enable the instruction cache
46	 * -----------------------------------------------------
47	 */
48	ldcopr	r0, SCTLR
49	orr	r0, r0, #SCTLR_I_BIT
50	stcopr	r0, SCTLR
51	isb
52
53	/* ---------------------------------------------
54	 * Since BL2U executes after BL1, it is assumed
55	 * here that BL1 has already has done the
56	 * necessary register initializations.
57	 * ---------------------------------------------
58	 */
59
60	/* ---------------------------------------------
61	 * Invalidate the RW memory used by the BL2U
62	 * image. This includes the data and NOBITS
63	 * sections. This is done to safeguard against
64	 * possible corruption of this memory by dirty
65	 * cache lines in a system cache as a result of
66	 * use by an earlier boot loader stage.
67	 * ---------------------------------------------
68	 */
69	ldr	r0, =__RW_START__
70	ldr	r1, =__RW_END__
71	sub	r1, r1, r0
72	bl	inv_dcache_range
73
74	/* ---------------------------------------------
75	 * Zero out NOBITS sections. There are 2 of them:
76	 *   - the .bss section;
77	 *   - the coherent memory section.
78	 * ---------------------------------------------
79	 */
80	ldr	r0, =__BSS_START__
81	ldr	r1, =__BSS_SIZE__
82	bl	zeromem
83
84	/* --------------------------------------------
85	 * Allocate a stack whose memory will be marked
86	 * as Normal-IS-WBWA when the MMU is enabled.
87	 * There is no risk of reading stale stack
88	 * memory after enabling the MMU as only the
89	 * primary cpu is running at the moment.
90	 * --------------------------------------------
91	 */
92	bl	plat_set_my_stack
93
94	/* ---------------------------------------------
95	 * Initialize the stack protector canary before
96	 * any C code is called.
97	 * ---------------------------------------------
98	 */
99#if STACK_PROTECTOR_ENABLED
100	bl	update_stack_protector_canary
101#endif
102
103	/* ---------------------------------------------
104	 * Perform early platform setup & platform
105	 * specific early arch. setup e.g. mmu setup
106	 * ---------------------------------------------
107	 */
108	mov	r0, r11
109	mov	r1, r10
110	bl	bl2u_early_platform_setup
111	bl	bl2u_plat_arch_setup
112
113	/* ---------------------------------------------
114	 * Jump to main function.
115	 * ---------------------------------------------
116	 */
117	bl	bl2u_main
118
119	/* ---------------------------------------------
120	 * Should never reach this point.
121	 * ---------------------------------------------
122	 */
123	no_ret	plat_panic_handler
124
125endfunc bl2u_entrypoint
126