xref: /rk3399_ARM-atf/bl2/bl2_main.c (revision 29fb905d5f36a415a170a4bffeadf13b5f084345)
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 <bl2.h>
36 #include <debug.h>
37 #include <platform.h>
38 #include <stdio.h>
39 #include "bl2_private.h"
40 
41 /*******************************************************************************
42  * Runs BL31 from the given entry point. It jumps to a higher exception level
43  * through an SMC.
44  ******************************************************************************/
45 static void __dead2 bl2_run_bl31(bl31_args_t *bl2_to_bl31_args,
46 				unsigned long arg1,
47 				unsigned long arg2)
48 {
49 	/* Set the args pointers for X0 and X1 to BL31 */
50 	bl2_to_bl31_args->bl31_image_info.args.arg0 = arg1;
51 	bl2_to_bl31_args->bl31_image_info.args.arg1 = arg2;
52 
53 	/* Flush the entire BL31 args buffer */
54 	flush_dcache_range((unsigned long) bl2_to_bl31_args,
55 			   sizeof(*bl2_to_bl31_args));
56 
57 	smc(RUN_IMAGE, (unsigned long)&bl2_to_bl31_args->bl31_image_info,
58 				0, 0, 0, 0, 0, 0);
59 }
60 
61 
62 /*******************************************************************************
63  * The only thing to do in BL2 is to load further images and pass control to
64  * BL31. The memory occupied by BL2 will be reclaimed by BL3_x stages. BL2 runs
65  * entirely in S-EL1. Since arm standard c libraries are not PIC, printf et al
66  * are not available. We rely on assertions to signal error conditions
67  ******************************************************************************/
68 void bl2_main(void)
69 {
70 	meminfo_t *bl2_tzram_layout;
71 	bl31_args_t *bl2_to_bl31_args;
72 	unsigned long bl31_base, bl32_base = 0, bl33_base, el_status;
73 	unsigned int bl2_load, bl31_load, mode;
74 
75 	/* Perform remaining generic architectural setup in S-El1 */
76 	bl2_arch_setup();
77 
78 	/* Perform platform setup in BL1 */
79 	bl2_platform_setup();
80 
81 	printf("BL2 %s\n\r", build_message);
82 
83 	/* Find out how much free trusted ram remains after BL2 load */
84 	bl2_tzram_layout = bl2_plat_sec_mem_layout();
85 
86 	/*
87 	 * Load BL31. BL1 tells BL2 whether it has been TOP or BOTTOM loaded.
88 	 * To avoid fragmentation of trusted SRAM memory, BL31 is always
89 	 * loaded opposite to BL2. This allows BL31 to reclaim BL2 memory
90 	 * while maintaining its free space in one contiguous chunk.
91 	 */
92 	bl2_load = bl2_tzram_layout->attr & LOAD_MASK;
93 	assert((bl2_load == TOP_LOAD) || (bl2_load == BOT_LOAD));
94 	bl31_load = (bl2_load == TOP_LOAD) ? BOT_LOAD : TOP_LOAD;
95 	bl31_base = load_image(bl2_tzram_layout, BL31_IMAGE_NAME,
96 	                       bl31_load, BL31_BASE);
97 
98 	/* Assert if it has not been possible to load BL31 */
99 	if (bl31_base == 0) {
100 		ERROR("Failed to load BL3-1.\n");
101 		panic();
102 	}
103 
104 	/*
105 	 * Get a pointer to the memory the platform has set aside to pass
106 	 * information to BL31.
107 	 */
108 	bl2_to_bl31_args = bl2_get_bl31_args_ptr();
109 
110 	bl2_to_bl31_args->bl31_image_info.entrypoint = bl31_base;
111 	bl2_to_bl31_args->bl31_image_info.spsr =
112 			SPSR_64(MODE_EL3, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS);
113 
114 	/*
115 	 * Create a new layout of memory for BL31 as seen by BL2. This
116 	 * will gobble up all the BL2 memory.
117 	 */
118 	init_bl31_mem_layout(bl2_tzram_layout,
119 			     &bl2_to_bl31_args->bl31_meminfo,
120 			     bl31_load);
121 
122 	/* Load the BL33 image in non-secure memory provided by the platform */
123 	bl33_base = load_image(&bl2_to_bl31_args->bl33_meminfo,
124 			       BL33_IMAGE_NAME,
125 			       BOT_LOAD,
126 			       plat_get_ns_image_entrypoint());
127 	/* Halt if failed to load normal world firmware. */
128 	if (bl33_base == 0) {
129 		ERROR("Failed to load BL3-3.\n");
130 		panic();
131 	}
132 
133 	/*
134 	 * BL2 also needs to tell BL31 where the non-trusted software image
135 	 * is located.
136 	 */
137 	bl2_to_bl31_args->bl33_image_info.entrypoint = bl33_base;
138 
139 	/* Figure out what mode we enter the non-secure world in */
140 	el_status = read_id_aa64pfr0_el1() >> ID_AA64PFR0_EL2_SHIFT;
141 	el_status &= ID_AA64PFR0_ELX_MASK;
142 
143 	if (el_status)
144 		mode = MODE_EL2;
145 	else
146 		mode = MODE_EL1;
147 
148 	/*
149 	 * TODO: Consider the possibility of specifying the SPSR in
150 	 * the FIP ToC and allowing the platform to have a say as
151 	 * well.
152 	 */
153 	bl2_to_bl31_args->bl33_image_info.spsr =
154 			SPSR_64(mode, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS);
155 	bl2_to_bl31_args->bl33_image_info.security_state = NON_SECURE;
156 
157 	/*
158 	 * Load the BL32 image if there's one. It is upto to platform
159 	 * to specify where BL32 should be loaded if it exists. It
160 	 * could create space in the secure sram or point to a
161 	 * completely different memory. A zero size indicates that the
162 	 * platform does not want to load a BL32 image.
163 	 */
164 	if (bl2_to_bl31_args->bl32_meminfo.total_size)
165 		bl32_base = load_image(&bl2_to_bl31_args->bl32_meminfo,
166 				       BL32_IMAGE_NAME,
167 				       bl2_to_bl31_args->bl32_meminfo.attr &
168 				       LOAD_MASK,
169 				       BL32_BASE);
170 
171 	if (bl32_base) {
172 		/* Fill BL32 image info */
173 		bl2_to_bl31_args->bl32_image_info.entrypoint = bl32_base;
174 		bl2_to_bl31_args->bl32_image_info.security_state = SECURE;
175 
176 		/*
177 		 * The Secure Payload Dispatcher service is responsible for
178 		 * setting the SPSR prior to entry into the BL32 image.
179 		 */
180 		bl2_to_bl31_args->bl32_image_info.spsr = 0;
181 	}
182 
183 	/*
184 	 * Run BL31 via an SMC to BL1. Information on how to pass control to
185 	 * the BL32 (if present) and BL33 software images will be passed to
186 	 * BL31 as an argument.
187 	 */
188 	 bl2_run_bl31(bl2_to_bl31_args, (unsigned long)bl2_to_bl31_args, 0);
189 }
190