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 <arch_helpers.h>
33 #include <assert.h>
34 #include <bl_common.h>
35 #include <bl31.h>
36 #include <context_mgmt.h>
37 #include <debug.h>
38 #include <platform.h>
39 #include <runtime_svc.h>
40 #include <string.h>
41
42 /*******************************************************************************
43 * This function pointer is used to initialise the BL32 image. It's initialized
44 * by SPD calling bl31_register_bl32_init after setting up all things necessary
45 * for SP execution. In cases where both SPD and SP are absent, or when SPD
46 * finds it impossible to execute SP, this pointer is left as NULL
47 ******************************************************************************/
48 static int32_t (*bl32_init)(void);
49
50 /*******************************************************************************
51 * Variable to indicate whether next image to execute after BL31 is BL33
52 * (non-secure & default) or BL32 (secure).
53 ******************************************************************************/
54 static uint32_t next_image_type = NON_SECURE;
55
56 /*******************************************************************************
57 * Simple function to initialise all BL31 helper libraries.
58 ******************************************************************************/
bl31_lib_init(void)59 void bl31_lib_init(void)
60 {
61 cm_init();
62 }
63
64 /*******************************************************************************
65 * BL31 is responsible for setting up the runtime services for the primary cpu
66 * before passing control to the bootloader or an Operating System. This
67 * function calls runtime_svc_init() which initializes all registered runtime
68 * services. The run time services would setup enough context for the core to
69 * swtich to the next exception level. When this function returns, the core will
70 * switch to the programmed exception level via. an ERET.
71 ******************************************************************************/
bl31_main(void)72 void bl31_main(void)
73 {
74 NOTICE("BL3-1: %s\n", version_string);
75 NOTICE("BL3-1: %s\n", build_message);
76
77 /* Perform remaining generic architectural setup from EL3 */
78 bl31_arch_setup();
79
80 /* Perform platform setup in BL1 */
81 bl31_platform_setup();
82
83 /* Initialise helper libraries */
84 bl31_lib_init();
85
86 /* Initialize the runtime services e.g. psci */
87 INFO("BL3-1: Initializing runtime services\n");
88 runtime_svc_init();
89
90 /* Clean caches before re-entering normal world */
91 dcsw_op_all(DCCSW);
92
93 /*
94 * All the cold boot actions on the primary cpu are done. We now need to
95 * decide which is the next image (BL32 or BL33) and how to execute it.
96 * If the SPD runtime service is present, it would want to pass control
97 * to BL32 first in S-EL1. In that case, SPD would have registered a
98 * function to intialize bl32 where it takes responsibility of entering
99 * S-EL1 and returning control back to bl31_main. Once this is done we
100 * can prepare entry into BL33 as normal.
101 */
102
103 /*
104 * If SPD had registerd an init hook, invoke it.
105 */
106 if (bl32_init) {
107 INFO("BL3-1: Initializing BL3-2\n");
108 (*bl32_init)();
109 }
110 /*
111 * We are ready to enter the next EL. Prepare entry into the image
112 * corresponding to the desired security state after the next ERET.
113 */
114 bl31_prepare_next_image_entry();
115 }
116
117 /*******************************************************************************
118 * Accessor functions to help runtime services decide which image should be
119 * executed after BL31. This is BL33 or the non-secure bootloader image by
120 * default but the Secure payload dispatcher could override this by requesting
121 * an entry into BL32 (Secure payload) first. If it does so then it should use
122 * the same API to program an entry into BL33 once BL32 initialisation is
123 * complete.
124 ******************************************************************************/
bl31_set_next_image_type(uint32_t security_state)125 void bl31_set_next_image_type(uint32_t security_state)
126 {
127 assert(sec_state_is_valid(security_state));
128 next_image_type = security_state;
129 }
130
bl31_get_next_image_type(void)131 uint32_t bl31_get_next_image_type(void)
132 {
133 return next_image_type;
134 }
135
136 /*******************************************************************************
137 * This function programs EL3 registers and performs other setup to enable entry
138 * into the next image after BL31 at the next ERET.
139 ******************************************************************************/
bl31_prepare_next_image_entry(void)140 void bl31_prepare_next_image_entry(void)
141 {
142 entry_point_info_t *next_image_info;
143 uint32_t image_type;
144
145 /* Determine which image to execute next */
146 image_type = bl31_get_next_image_type();
147
148 /* Program EL3 registers to enable entry into the next EL */
149 next_image_info = bl31_plat_get_next_image_ep_info(image_type);
150 assert(next_image_info);
151 assert(image_type == GET_SECURITY_STATE(next_image_info->h.attr));
152
153 INFO("BL3-1: Preparing for EL3 exit to %s world\n",
154 (image_type == SECURE) ? "secure" : "normal");
155 INFO("BL3-1: Next image address = 0x%llx\n",
156 (unsigned long long) next_image_info->pc);
157 INFO("BL3-1: Next image spsr = 0x%x\n", next_image_info->spsr);
158 cm_init_context(read_mpidr_el1(), next_image_info);
159 cm_prepare_el3_exit(image_type);
160 }
161
162 /*******************************************************************************
163 * This function initializes the pointer to BL32 init function. This is expected
164 * to be called by the SPD after it finishes all its initialization
165 ******************************************************************************/
bl31_register_bl32_init(int32_t (* func)(void))166 void bl31_register_bl32_init(int32_t (*func)(void))
167 {
168 bl32_init = func;
169 }
170