xref: /rk3399_ARM-atf/bl31/aarch64/bl31_entrypoint.S (revision 539a7b383d52493a94df4f5da8f74aa102429fa0)
1/*
2 * Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are met:
6 *
7 * Redistributions of source code must retain the above copyright notice, this
8 * list of conditions and the following disclaimer.
9 *
10 * Redistributions in binary form must reproduce the above copyright notice,
11 * this list of conditions and the following disclaimer in the documentation
12 * and/or other materials provided with the distribution.
13 *
14 * Neither the name of ARM nor the names of its contributors may be used
15 * to endorse or promote products derived from this software without specific
16 * prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include <arch.h>
32#include <asm_macros.S>
33#include <bl_common.h>
34
35	.globl	bl31_entrypoint
36
37
38	/* -----------------------------------------------------
39	 * bl31_entrypoint() is the cold boot entrypoint,
40	 * executed only by the primary cpu.
41	 * -----------------------------------------------------
42	 */
43
44func bl31_entrypoint
45	/* ---------------------------------------------------------------
46	 * Preceding bootloader has populated x0 with a pointer to a
47	 * 'bl31_params' structure & x1 with a pointer to platform
48	 * specific structure
49	 * ---------------------------------------------------------------
50	 */
51#if !RESET_TO_BL31
52	mov	x20, x0
53	mov	x21, x1
54#else
55
56	/* -----------------------------------------------------
57	 * Perform any processor specific actions upon reset
58	 * e.g. cache, tlb invalidations etc. Override the
59	 * Boot ROM(BL0) programming sequence
60	 * -----------------------------------------------------
61	 */
62	bl	cpu_reset_handler
63#endif
64
65	/* ---------------------------------------------
66	 * Enable the instruction cache.
67	 * ---------------------------------------------
68	 */
69	mrs	x1, sctlr_el3
70	orr	x1, x1, #SCTLR_I_BIT
71	msr	sctlr_el3, x1
72	isb
73
74	/* ---------------------------------------------
75	 * Set the exception vector and zero tpidr_el3
76	 * until the crash reporting is set up
77	 * ---------------------------------------------
78	 */
79	adr	x1, runtime_exceptions
80	msr	vbar_el3, x1
81	msr	tpidr_el3, xzr
82
83	/* ---------------------------------------------------------------------
84	 * The initial state of the Architectural feature trap register
85	 * (CPTR_EL3) is unknown and it must be set to a known state. All
86	 * feature traps are disabled. Some bits in this register are marked as
87	 * Reserved and should not be modified.
88	 *
89	 * CPTR_EL3.TCPAC: This causes a direct access to the CPACR_EL1 from EL1
90	 *  or the CPTR_EL2 from EL2 to trap to EL3 unless it is trapped at EL2.
91	 * CPTR_EL3.TTA: This causes access to the Trace functionality to trap
92	 *  to EL3 when executed from EL0, EL1, EL2, or EL3. If system register
93	 *  access to trace functionality is not supported, this bit is RES0.
94	 * CPTR_EL3.TFP: This causes instructions that access the registers
95	 *  associated with Floating Point and Advanced SIMD execution to trap
96	 *  to EL3 when executed from any exception level, unless trapped to EL1
97	 *  or EL2.
98	 * ---------------------------------------------------------------------
99	 */
100	mrs	x1, cptr_el3
101	bic	w1, w1, #TCPAC_BIT
102	bic	w1, w1, #TTA_BIT
103	bic	w1, w1, #TFP_BIT
104	msr	cptr_el3, x1
105
106#if RESET_TO_BL31
107	/* -------------------------------------------------------
108	 * Will not return from this macro if it is a warm boot.
109	 * -------------------------------------------------------
110	 */
111	wait_for_entrypoint
112	bl	platform_mem_init
113#else
114	/* ---------------------------------------------
115	 * This is BL31 which is expected to be executed
116	 * only by the primary cpu (at least for now).
117	 * So, make sure no secondary has lost its way.
118	 * ---------------------------------------------
119	 */
120	mrs	x0, mpidr_el1
121	bl	platform_is_primary_cpu
122	cbz	x0, _panic
123#endif
124
125	/* ---------------------------------------------
126	 * Zero out NOBITS sections. There are 2 of them:
127	 *   - the .bss section;
128	 *   - the coherent memory section.
129	 * ---------------------------------------------
130	 */
131	ldr	x0, =__BSS_START__
132	ldr	x1, =__BSS_SIZE__
133	bl	zeromem16
134
135	ldr	x0, =__COHERENT_RAM_START__
136	ldr	x1, =__COHERENT_RAM_UNALIGNED_SIZE__
137	bl	zeromem16
138
139	/* ---------------------------------------------
140	 * Initialise cpu_data and crash reporting
141	 * ---------------------------------------------
142	 */
143#if CRASH_REPORTING
144	bl	init_crash_reporting
145#endif
146	bl	init_cpu_data_ptr
147
148	/* ---------------------------------------------
149	 * Use SP_EL0 for the C runtime stack.
150	 * ---------------------------------------------
151	 */
152	msr	spsel, #0
153
154	/* --------------------------------------------
155	 * Allocate a stack whose memory will be marked
156	 * as Normal-IS-WBWA when the MMU is enabled.
157	 * There is no risk of reading stale stack
158	 * memory after enabling the MMU as only the
159	 * primary cpu is running at the moment.
160	 * --------------------------------------------
161	 */
162	mrs	x0, mpidr_el1
163	bl	platform_set_stack
164
165	/* ---------------------------------------------
166	 * Perform platform specific early arch. setup
167	 * ---------------------------------------------
168	 */
169#if RESET_TO_BL31
170	mov	x0, 0
171	mov	x1, 0
172#else
173	mov	x0, x20
174	mov	x1, x21
175#endif
176
177	bl	bl31_early_platform_setup
178	bl	bl31_plat_arch_setup
179
180	/* ---------------------------------------------
181	 * Jump to main function.
182	 * ---------------------------------------------
183	 */
184	bl	bl31_main
185
186	b	el3_exit
187
188_panic:
189	wfi
190	b	_panic
191