xref: /aosp_15_r20/external/arm-trusted-firmware/bl2/aarch32/bl2_entrypoint.S (revision 54fd6939e177f8ff529b10183254802c76df6d08)
1*54fd6939SJiyong Park/*
2*54fd6939SJiyong Park * Copyright (c) 2016-2021, ARM Limited and Contributors. All rights reserved.
3*54fd6939SJiyong Park *
4*54fd6939SJiyong Park * SPDX-License-Identifier: BSD-3-Clause
5*54fd6939SJiyong Park */
6*54fd6939SJiyong Park
7*54fd6939SJiyong Park#include <arch.h>
8*54fd6939SJiyong Park#include <asm_macros.S>
9*54fd6939SJiyong Park#include <common/bl_common.h>
10*54fd6939SJiyong Park
11*54fd6939SJiyong Park	.globl	bl2_vector_table
12*54fd6939SJiyong Park	.globl	bl2_entrypoint
13*54fd6939SJiyong Park
14*54fd6939SJiyong Park
15*54fd6939SJiyong Parkvector_base bl2_vector_table
16*54fd6939SJiyong Park	b	bl2_entrypoint
17*54fd6939SJiyong Park	b	report_exception	/* Undef */
18*54fd6939SJiyong Park	b	report_exception	/* SVC call */
19*54fd6939SJiyong Park	b	report_exception	/* Prefetch abort */
20*54fd6939SJiyong Park	b	report_exception	/* Data abort */
21*54fd6939SJiyong Park	b	report_exception	/* Reserved */
22*54fd6939SJiyong Park	b	report_exception	/* IRQ */
23*54fd6939SJiyong Park	b	report_exception	/* FIQ */
24*54fd6939SJiyong Park
25*54fd6939SJiyong Park
26*54fd6939SJiyong Parkfunc bl2_entrypoint
27*54fd6939SJiyong Park	/*---------------------------------------------
28*54fd6939SJiyong Park	 * Save arguments x0 - x3 from BL1 for future
29*54fd6939SJiyong Park	 * use.
30*54fd6939SJiyong Park	 * ---------------------------------------------
31*54fd6939SJiyong Park	 */
32*54fd6939SJiyong Park	mov	r9, r0
33*54fd6939SJiyong Park	mov	r10, r1
34*54fd6939SJiyong Park	mov	r11, r2
35*54fd6939SJiyong Park	mov	r12, r3
36*54fd6939SJiyong Park
37*54fd6939SJiyong Park	/* ---------------------------------------------
38*54fd6939SJiyong Park	 * Set the exception vector to something sane.
39*54fd6939SJiyong Park	 * ---------------------------------------------
40*54fd6939SJiyong Park	 */
41*54fd6939SJiyong Park	ldr	r0, =bl2_vector_table
42*54fd6939SJiyong Park	stcopr	r0, VBAR
43*54fd6939SJiyong Park	isb
44*54fd6939SJiyong Park
45*54fd6939SJiyong Park	/* --------------------------------------------------------
46*54fd6939SJiyong Park	 * Enable the instruction cache - disable speculative loads
47*54fd6939SJiyong Park	 * --------------------------------------------------------
48*54fd6939SJiyong Park	 */
49*54fd6939SJiyong Park	ldcopr	r0, SCTLR
50*54fd6939SJiyong Park	orr	r0, r0, #SCTLR_I_BIT
51*54fd6939SJiyong Park	bic	r0, r0, #SCTLR_DSSBS_BIT
52*54fd6939SJiyong Park	stcopr	r0, SCTLR
53*54fd6939SJiyong Park	isb
54*54fd6939SJiyong Park
55*54fd6939SJiyong Park	/* ---------------------------------------------
56*54fd6939SJiyong Park	 * Since BL2 executes after BL1, it is assumed
57*54fd6939SJiyong Park	 * here that BL1 has already has done the
58*54fd6939SJiyong Park	 * necessary register initializations.
59*54fd6939SJiyong Park	 * ---------------------------------------------
60*54fd6939SJiyong Park	 */
61*54fd6939SJiyong Park
62*54fd6939SJiyong Park	/* ---------------------------------------------
63*54fd6939SJiyong Park	 * Invalidate the RW memory used by the BL2
64*54fd6939SJiyong Park	 * image. This includes the data and NOBITS
65*54fd6939SJiyong Park	 * sections. This is done to safeguard against
66*54fd6939SJiyong Park	 * possible corruption of this memory by dirty
67*54fd6939SJiyong Park	 * cache lines in a system cache as a result of
68*54fd6939SJiyong Park	 * use by an earlier boot loader stage.
69*54fd6939SJiyong Park	 * ---------------------------------------------
70*54fd6939SJiyong Park	 */
71*54fd6939SJiyong Park	ldr	r0, =__RW_START__
72*54fd6939SJiyong Park	ldr	r1, =__RW_END__
73*54fd6939SJiyong Park	sub	r1, r1, r0
74*54fd6939SJiyong Park	bl	inv_dcache_range
75*54fd6939SJiyong Park
76*54fd6939SJiyong Park	/* ---------------------------------------------
77*54fd6939SJiyong Park	 * Zero out NOBITS sections. There are 2 of them:
78*54fd6939SJiyong Park	 *   - the .bss section;
79*54fd6939SJiyong Park	 *   - the coherent memory section.
80*54fd6939SJiyong Park	 * ---------------------------------------------
81*54fd6939SJiyong Park	 */
82*54fd6939SJiyong Park	ldr	r0, =__BSS_START__
83*54fd6939SJiyong Park	ldr	r1, =__BSS_END__
84*54fd6939SJiyong Park	sub 	r1, r1, r0
85*54fd6939SJiyong Park	bl	zeromem
86*54fd6939SJiyong Park
87*54fd6939SJiyong Park#if USE_COHERENT_MEM
88*54fd6939SJiyong Park	ldr	r0, =__COHERENT_RAM_START__
89*54fd6939SJiyong Park	ldr	r1, =__COHERENT_RAM_END_UNALIGNED__
90*54fd6939SJiyong Park	sub 	r1, r1, r0
91*54fd6939SJiyong Park	bl	zeromem
92*54fd6939SJiyong Park#endif
93*54fd6939SJiyong Park
94*54fd6939SJiyong Park	/* --------------------------------------------
95*54fd6939SJiyong Park	 * Allocate a stack whose memory will be marked
96*54fd6939SJiyong Park	 * as Normal-IS-WBWA when the MMU is enabled.
97*54fd6939SJiyong Park	 * There is no risk of reading stale stack
98*54fd6939SJiyong Park	 * memory after enabling the MMU as only the
99*54fd6939SJiyong Park	 * primary cpu is running at the moment.
100*54fd6939SJiyong Park	 * --------------------------------------------
101*54fd6939SJiyong Park	 */
102*54fd6939SJiyong Park	bl	plat_set_my_stack
103*54fd6939SJiyong Park
104*54fd6939SJiyong Park	/* ---------------------------------------------
105*54fd6939SJiyong Park	 * Initialize the stack protector canary before
106*54fd6939SJiyong Park	 * any C code is called.
107*54fd6939SJiyong Park	 * ---------------------------------------------
108*54fd6939SJiyong Park	 */
109*54fd6939SJiyong Park#if STACK_PROTECTOR_ENABLED
110*54fd6939SJiyong Park	bl	update_stack_protector_canary
111*54fd6939SJiyong Park#endif
112*54fd6939SJiyong Park
113*54fd6939SJiyong Park	/* ---------------------------------------------
114*54fd6939SJiyong Park	 * Perform BL2 setup
115*54fd6939SJiyong Park	 * ---------------------------------------------
116*54fd6939SJiyong Park	 */
117*54fd6939SJiyong Park	mov	r0, r9
118*54fd6939SJiyong Park	mov	r1, r10
119*54fd6939SJiyong Park	mov	r2, r11
120*54fd6939SJiyong Park	mov	r3, r12
121*54fd6939SJiyong Park
122*54fd6939SJiyong Park	bl	bl2_setup
123*54fd6939SJiyong Park
124*54fd6939SJiyong Park	/* ---------------------------------------------
125*54fd6939SJiyong Park	 * Jump to main function.
126*54fd6939SJiyong Park	 * ---------------------------------------------
127*54fd6939SJiyong Park	 */
128*54fd6939SJiyong Park	bl	bl2_main
129*54fd6939SJiyong Park
130*54fd6939SJiyong Park	/* ---------------------------------------------
131*54fd6939SJiyong Park	 * Should never reach this point.
132*54fd6939SJiyong Park	 * ---------------------------------------------
133*54fd6939SJiyong Park	 */
134*54fd6939SJiyong Park	no_ret	plat_panic_handler
135*54fd6939SJiyong Park
136*54fd6939SJiyong Parkendfunc bl2_entrypoint
137