xref: /rk3399_ARM-atf/bl31/bl31_main.c (revision 40d553cfde38d4f68449c62967cd1ce0d6478750)
1 /*
2  * Copyright (c) 2013-2019, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 #include <string.h>
9 
10 #include <arch.h>
11 #include <arch_helpers.h>
12 #include <bl31/bl31.h>
13 #include <bl31/ehf.h>
14 #include <common/bl_common.h>
15 #include <common/debug.h>
16 #include <common/runtime_svc.h>
17 #include <drivers/console.h>
18 #include <lib/el3_runtime/context_mgmt.h>
19 #include <lib/pmf/pmf.h>
20 #include <lib/runtime_instr.h>
21 #include <plat/common/platform.h>
22 #include <services/std_svc.h>
23 
24 #if ENABLE_RUNTIME_INSTRUMENTATION
25 PMF_REGISTER_SERVICE_SMC(rt_instr_svc, PMF_RT_INSTR_SVC_ID,
26 	RT_INSTR_TOTAL_IDS, PMF_STORE_ENABLE)
27 #endif
28 
29 /*******************************************************************************
30  * This function pointer is used to initialise the BL32 image. It's initialized
31  * by SPD calling bl31_register_bl32_init after setting up all things necessary
32  * for SP execution. In cases where both SPD and SP are absent, or when SPD
33  * finds it impossible to execute SP, this pointer is left as NULL
34  ******************************************************************************/
35 static int32_t (*bl32_init)(void);
36 
37 /*******************************************************************************
38  * Variable to indicate whether next image to execute after BL31 is BL33
39  * (non-secure & default) or BL32 (secure).
40  ******************************************************************************/
41 static uint32_t next_image_type = NON_SECURE;
42 
43 /*
44  * Implement the ARM Standard Service function to get arguments for a
45  * particular service.
46  */
47 uintptr_t get_arm_std_svc_args(unsigned int svc_mask)
48 {
49 	/* Setup the arguments for PSCI Library */
50 	DEFINE_STATIC_PSCI_LIB_ARGS_V1(psci_args, bl31_warm_entrypoint);
51 
52 	/* PSCI is the only ARM Standard Service implemented */
53 	assert(svc_mask == PSCI_FID_MASK);
54 
55 	return (uintptr_t)&psci_args;
56 }
57 
58 /*******************************************************************************
59  * Simple function to initialise all BL31 helper libraries.
60  ******************************************************************************/
61 void __init bl31_lib_init(void)
62 {
63 	cm_init();
64 }
65 
66 /*******************************************************************************
67  * Setup function for BL31.
68  ******************************************************************************/
69 void bl31_setup(u_register_t arg0, u_register_t arg1, u_register_t arg2,
70 		u_register_t arg3)
71 {
72 	/* Perform early platform-specific setup */
73 	bl31_early_platform_setup2(arg0, arg1, arg2, arg3);
74 
75 	/*
76 	 * Update pointer authentication key before the MMU is enabled. It is
77 	 * saved in the rodata section, that can be writen before enabling the
78 	 * MMU. This function must be called after the console is initialized
79 	 * in the early platform setup.
80 	 */
81 	bl_handle_pauth();
82 
83 	/* Perform late platform-specific setup */
84 	bl31_plat_arch_setup();
85 }
86 
87 /*******************************************************************************
88  * BL31 is responsible for setting up the runtime services for the primary cpu
89  * before passing control to the bootloader or an Operating System. This
90  * function calls runtime_svc_init() which initializes all registered runtime
91  * services. The run time services would setup enough context for the core to
92  * switch to the next exception level. When this function returns, the core will
93  * switch to the programmed exception level via an ERET.
94  ******************************************************************************/
95 void bl31_main(void)
96 {
97 	NOTICE("BL31: %s\n", version_string);
98 	NOTICE("BL31: %s\n", build_message);
99 
100 	/* Perform platform setup in BL31 */
101 	bl31_platform_setup();
102 
103 	/* Initialise helper libraries */
104 	bl31_lib_init();
105 
106 #if EL3_EXCEPTION_HANDLING
107 	INFO("BL31: Initialising Exception Handling Framework\n");
108 	ehf_init();
109 #endif
110 
111 	/* Initialize the runtime services e.g. psci. */
112 	INFO("BL31: Initializing runtime services\n");
113 	runtime_svc_init();
114 
115 	/*
116 	 * All the cold boot actions on the primary cpu are done. We now need to
117 	 * decide which is the next image (BL32 or BL33) and how to execute it.
118 	 * If the SPD runtime service is present, it would want to pass control
119 	 * to BL32 first in S-EL1. In that case, SPD would have registered a
120 	 * function to initialize bl32 where it takes responsibility of entering
121 	 * S-EL1 and returning control back to bl31_main. Once this is done we
122 	 * can prepare entry into BL33 as normal.
123 	 */
124 
125 	/*
126 	 * If SPD had registered an init hook, invoke it.
127 	 */
128 	if (bl32_init != NULL) {
129 		INFO("BL31: Initializing BL32\n");
130 
131 		int32_t rc = (*bl32_init)();
132 
133 		if (rc == 0)
134 			WARN("BL31: BL32 initialization failed\n");
135 	}
136 	/*
137 	 * We are ready to enter the next EL. Prepare entry into the image
138 	 * corresponding to the desired security state after the next ERET.
139 	 */
140 	bl31_prepare_next_image_entry();
141 
142 	console_flush();
143 
144 	/*
145 	 * Perform any platform specific runtime setup prior to cold boot exit
146 	 * from BL31
147 	 */
148 	bl31_plat_runtime_setup();
149 }
150 
151 /*******************************************************************************
152  * Accessor functions to help runtime services decide which image should be
153  * executed after BL31. This is BL33 or the non-secure bootloader image by
154  * default but the Secure payload dispatcher could override this by requesting
155  * an entry into BL32 (Secure payload) first. If it does so then it should use
156  * the same API to program an entry into BL33 once BL32 initialisation is
157  * complete.
158  ******************************************************************************/
159 void bl31_set_next_image_type(uint32_t security_state)
160 {
161 	assert(sec_state_is_valid(security_state));
162 	next_image_type = security_state;
163 }
164 
165 uint32_t bl31_get_next_image_type(void)
166 {
167 	return next_image_type;
168 }
169 
170 /*******************************************************************************
171  * This function programs EL3 registers and performs other setup to enable entry
172  * into the next image after BL31 at the next ERET.
173  ******************************************************************************/
174 void __init bl31_prepare_next_image_entry(void)
175 {
176 	entry_point_info_t *next_image_info;
177 	uint32_t image_type;
178 
179 #if CTX_INCLUDE_AARCH32_REGS
180 	/*
181 	 * Ensure that the build flag to save AArch32 system registers in CPU
182 	 * context is not set for AArch64-only platforms.
183 	 */
184 	if (el_implemented(1) == EL_IMPL_A64ONLY) {
185 		ERROR("EL1 supports AArch64-only. Please set build flag "
186 				"CTX_INCLUDE_AARCH32_REGS = 0\n");
187 		panic();
188 	}
189 #endif
190 
191 	/* Determine which image to execute next */
192 	image_type = bl31_get_next_image_type();
193 
194 	/* Program EL3 registers to enable entry into the next EL */
195 	next_image_info = bl31_plat_get_next_image_ep_info(image_type);
196 	assert(next_image_info != NULL);
197 	assert(image_type == GET_SECURITY_STATE(next_image_info->h.attr));
198 
199 	INFO("BL31: Preparing for EL3 exit to %s world\n",
200 		(image_type == SECURE) ? "secure" : "normal");
201 	print_entry_point_info(next_image_info);
202 	cm_init_my_context(next_image_info);
203 	cm_prepare_el3_exit(image_type);
204 }
205 
206 /*******************************************************************************
207  * This function initializes the pointer to BL32 init function. This is expected
208  * to be called by the SPD after it finishes all its initialization
209  ******************************************************************************/
210 void bl31_register_bl32_init(int32_t (*func)(void))
211 {
212 	bl32_init = func;
213 }
214