1 /*
2  * Copyright (c) 2013-2021, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 
9 #include <arch_helpers.h>
10 #include <arch_features.h>
11 #include <bl1/bl1.h>
12 #include <bl2/bl2.h>
13 #include <common/bl_common.h>
14 #include <common/debug.h>
15 #include <drivers/auth/auth_mod.h>
16 #include <drivers/console.h>
17 #include <drivers/fwu/fwu.h>
18 #if MEASURED_BOOT
19 #include <drivers/measured_boot/measured_boot.h>
20 #endif
21 #include <lib/extensions/pauth.h>
22 #include <plat/common/platform.h>
23 
24 #include "bl2_private.h"
25 
26 #ifdef __aarch64__
27 #define NEXT_IMAGE	"BL31"
28 #else
29 #define NEXT_IMAGE	"BL32"
30 #endif
31 
32 #if !BL2_AT_EL3
33 /*******************************************************************************
34  * Setup function for BL2.
35  ******************************************************************************/
bl2_setup(u_register_t arg0,u_register_t arg1,u_register_t arg2,u_register_t arg3)36 void bl2_setup(u_register_t arg0, u_register_t arg1, u_register_t arg2,
37 	       u_register_t arg3)
38 {
39 	/* Perform early platform-specific setup */
40 	bl2_early_platform_setup2(arg0, arg1, arg2, arg3);
41 
42 	/* Perform late platform-specific setup */
43 	bl2_plat_arch_setup();
44 
45 #if CTX_INCLUDE_PAUTH_REGS
46 	/*
47 	 * Assert that the ARMv8.3-PAuth registers are present or an access
48 	 * fault will be triggered when they are being saved or restored.
49 	 */
50 	assert(is_armv8_3_pauth_present());
51 #endif /* CTX_INCLUDE_PAUTH_REGS */
52 }
53 
54 #else /* if BL2_AT_EL3 */
55 /*******************************************************************************
56  * Setup function for BL2 when BL2_AT_EL3=1.
57  ******************************************************************************/
bl2_el3_setup(u_register_t arg0,u_register_t arg1,u_register_t arg2,u_register_t arg3)58 void bl2_el3_setup(u_register_t arg0, u_register_t arg1, u_register_t arg2,
59 		   u_register_t arg3)
60 {
61 	/* Perform early platform-specific setup */
62 	bl2_el3_early_platform_setup(arg0, arg1, arg2, arg3);
63 
64 	/* Perform late platform-specific setup */
65 	bl2_el3_plat_arch_setup();
66 
67 #if CTX_INCLUDE_PAUTH_REGS
68 	/*
69 	 * Assert that the ARMv8.3-PAuth registers are present or an access
70 	 * fault will be triggered when they are being saved or restored.
71 	 */
72 	assert(is_armv8_3_pauth_present());
73 #endif /* CTX_INCLUDE_PAUTH_REGS */
74 }
75 #endif /* BL2_AT_EL3 */
76 
77 /*******************************************************************************
78  * The only thing to do in BL2 is to load further images and pass control to
79  * next BL. The memory occupied by BL2 will be reclaimed by BL3x stages. BL2
80  * runs entirely in S-EL1.
81  ******************************************************************************/
bl2_main(void)82 void bl2_main(void)
83 {
84 	entry_point_info_t *next_bl_ep_info;
85 
86 	NOTICE("BL2: %s\n", version_string);
87 	NOTICE("BL2: %s\n", build_message);
88 
89 	/* Perform remaining generic architectural setup in S-EL1 */
90 	bl2_arch_setup();
91 
92 #if PSA_FWU_SUPPORT
93 	fwu_init();
94 #endif /* PSA_FWU_SUPPORT */
95 
96 #if TRUSTED_BOARD_BOOT
97 	/* Initialize authentication module */
98 	auth_mod_init();
99 
100 #if MEASURED_BOOT
101 	/* Initialize measured boot module */
102 	measured_boot_init();
103 
104 #endif /* MEASURED_BOOT */
105 #endif /* TRUSTED_BOARD_BOOT */
106 
107 	/* Initialize boot source */
108 	bl2_plat_preload_setup();
109 
110 	/* Load the subsequent bootloader images. */
111 	next_bl_ep_info = bl2_load_images();
112 
113 #if MEASURED_BOOT
114 	/* Finalize measured boot */
115 	measured_boot_finish();
116 #endif /* MEASURED_BOOT */
117 
118 #if !BL2_AT_EL3
119 #ifndef __aarch64__
120 	/*
121 	 * For AArch32 state BL1 and BL2 share the MMU setup.
122 	 * Given that BL2 does not map BL1 regions, MMU needs
123 	 * to be disabled in order to go back to BL1.
124 	 */
125 	disable_mmu_icache_secure();
126 #endif /* !__aarch64__ */
127 
128 	console_flush();
129 
130 #if ENABLE_PAUTH
131 	/*
132 	 * Disable pointer authentication before running next boot image
133 	 */
134 	pauth_disable_el1();
135 #endif /* ENABLE_PAUTH */
136 
137 	/*
138 	 * Run next BL image via an SMC to BL1. Information on how to pass
139 	 * control to the BL32 (if present) and BL33 software images will
140 	 * be passed to next BL image as an argument.
141 	 */
142 	smc(BL1_SMC_RUN_IMAGE, (unsigned long)next_bl_ep_info, 0, 0, 0, 0, 0, 0);
143 #else /* if BL2_AT_EL3 */
144 	NOTICE("BL2: Booting " NEXT_IMAGE "\n");
145 	print_entry_point_info(next_bl_ep_info);
146 	console_flush();
147 
148 #if ENABLE_PAUTH
149 	/*
150 	 * Disable pointer authentication before running next boot image
151 	 */
152 	pauth_disable_el3();
153 #endif /* ENABLE_PAUTH */
154 
155 	bl2_run_next_image(next_bl_ep_info);
156 #endif /* BL2_AT_EL3 */
157 }
158