xref: /rk3399_ARM-atf/bl31/aarch64/bl31_entrypoint.S (revision 235585b1932d976167f49f7d19a963af8acbc8ac)
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	 * Set the CPU endianness before doing anything
57	 * that might involve memory reads or writes.
58	 * ---------------------------------------------
59	 */
60	mrs	x0, sctlr_el3
61	bic	x0, x0, #SCTLR_EE_BIT
62	msr	sctlr_el3, x0
63	isb
64
65	/* -----------------------------------------------------
66	 * Perform any processor specific actions upon reset
67	 * e.g. cache, tlb invalidations etc. Override the
68	 * Boot ROM(BL0) programming sequence
69	 * -----------------------------------------------------
70	 */
71	bl	reset_handler
72#endif
73	/* ---------------------------------------------
74	 * Enable the instruction cache, stack pointer
75	 * and data access alignment checks
76	 * ---------------------------------------------
77	 */
78	mov	x1, #(SCTLR_I_BIT | SCTLR_A_BIT | SCTLR_SA_BIT)
79	mrs	x0, sctlr_el3
80	orr	x0, x0, x1
81	msr	sctlr_el3, x0
82	isb
83
84	/* ---------------------------------------------
85	 * Initialise cpu_data early to enable crash
86	 * reporting to have access to crash stack.
87	 * Since crash reporting depends on cpu_data to
88	 * report the unhandled exception, not
89	 * doing so can lead to recursive exceptions due
90	 * to a NULL TPIDR_EL3
91	 * ---------------------------------------------
92	 */
93	bl	init_cpu_data_ptr
94
95	/* ---------------------------------------------
96	 * Set the exception vector.
97	 * ---------------------------------------------
98	 */
99	adr	x1, runtime_exceptions
100	msr	vbar_el3, x1
101	isb
102
103	/* ---------------------------------------------
104	 * Enable the SError interrupt now that the
105	 * exception vectors have been setup.
106	 * ---------------------------------------------
107	 */
108	msr	daifclr, #DAIF_ABT_BIT
109
110	/* ---------------------------------------------------------------------
111	 * The initial state of the Architectural feature trap register
112	 * (CPTR_EL3) is unknown and it must be set to a known state. All
113	 * feature traps are disabled. Some bits in this register are marked as
114	 * Reserved and should not be modified.
115	 *
116	 * CPTR_EL3.TCPAC: This causes a direct access to the CPACR_EL1 from EL1
117	 *  or the CPTR_EL2 from EL2 to trap to EL3 unless it is trapped at EL2.
118	 * CPTR_EL3.TTA: This causes access to the Trace functionality to trap
119	 *  to EL3 when executed from EL0, EL1, EL2, or EL3. If system register
120	 *  access to trace functionality is not supported, this bit is RES0.
121	 * CPTR_EL3.TFP: This causes instructions that access the registers
122	 *  associated with Floating Point and Advanced SIMD execution to trap
123	 *  to EL3 when executed from any exception level, unless trapped to EL1
124	 *  or EL2.
125	 * ---------------------------------------------------------------------
126	 */
127	mrs	x1, cptr_el3
128	bic	w1, w1, #TCPAC_BIT
129	bic	w1, w1, #TTA_BIT
130	bic	w1, w1, #TFP_BIT
131	msr	cptr_el3, x1
132
133#if RESET_TO_BL31
134	/* -------------------------------------------------------
135	 * Will not return from this macro if it is a warm boot.
136	 * -------------------------------------------------------
137	 */
138	wait_for_entrypoint
139	bl	platform_mem_init
140#endif
141
142	/* ---------------------------------------------
143	 * Zero out NOBITS sections. There are 2 of them:
144	 *   - the .bss section;
145	 *   - the coherent memory section.
146	 * ---------------------------------------------
147	 */
148	ldr	x0, =__BSS_START__
149	ldr	x1, =__BSS_SIZE__
150	bl	zeromem16
151
152	ldr	x0, =__COHERENT_RAM_START__
153	ldr	x1, =__COHERENT_RAM_UNALIGNED_SIZE__
154	bl	zeromem16
155
156	/* ---------------------------------------------
157	 * Initialize the cpu_ops pointer.
158	 * ---------------------------------------------
159	 */
160	bl	init_cpu_ops
161
162	/* ---------------------------------------------
163	 * Use SP_EL0 for the C runtime stack.
164	 * ---------------------------------------------
165	 */
166	msr	spsel, #0
167
168	/* --------------------------------------------
169	 * Allocate a stack whose memory will be marked
170	 * as Normal-IS-WBWA when the MMU is enabled.
171	 * There is no risk of reading stale stack
172	 * memory after enabling the MMU as only the
173	 * primary cpu is running at the moment.
174	 * --------------------------------------------
175	 */
176	mrs	x0, mpidr_el1
177	bl	platform_set_stack
178
179	/* ---------------------------------------------
180	 * Perform platform specific early arch. setup
181	 * ---------------------------------------------
182	 */
183#if RESET_TO_BL31
184	mov	x0, 0
185	mov	x1, 0
186#else
187	mov	x0, x20
188	mov	x1, x21
189#endif
190
191	bl	bl31_early_platform_setup
192	bl	bl31_plat_arch_setup
193
194	/* ---------------------------------------------
195	 * Jump to main function.
196	 * ---------------------------------------------
197	 */
198	bl	bl31_main
199
200	b	el3_exit
201