xref: /rk3399_ARM-atf/bl31/bl31_main.c (revision 530ceda57288aa931d0c8ba7b3066340d587cc9b)
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_features.h>
12 #include <arch_helpers.h>
13 #include <bl31/bl31.h>
14 #include <bl31/ehf.h>
15 #include <common/bl_common.h>
16 #include <common/debug.h>
17 #include <common/runtime_svc.h>
18 #include <drivers/console.h>
19 #include <lib/el3_runtime/context_mgmt.h>
20 #include <lib/pmf/pmf.h>
21 #include <lib/runtime_instr.h>
22 #include <plat/common/platform.h>
23 #include <services/std_svc.h>
24 
25 #if ENABLE_RUNTIME_INSTRUMENTATION
26 PMF_REGISTER_SERVICE_SMC(rt_instr_svc, PMF_RT_INSTR_SVC_ID,
27 	RT_INSTR_TOTAL_IDS, PMF_STORE_ENABLE)
28 #endif
29 
30 /*******************************************************************************
31  * This function pointer is used to initialise the BL32 image. It's initialized
32  * by SPD calling bl31_register_bl32_init after setting up all things necessary
33  * for SP execution. In cases where both SPD and SP are absent, or when SPD
34  * finds it impossible to execute SP, this pointer is left as NULL
35  ******************************************************************************/
36 static int32_t (*bl32_init)(void);
37 
38 /*******************************************************************************
39  * Variable to indicate whether next image to execute after BL31 is BL33
40  * (non-secure & default) or BL32 (secure).
41  ******************************************************************************/
42 static uint32_t next_image_type = NON_SECURE;
43 
44 /*
45  * Implement the ARM Standard Service function to get arguments for a
46  * particular service.
47  */
48 uintptr_t get_arm_std_svc_args(unsigned int svc_mask)
49 {
50 	/* Setup the arguments for PSCI Library */
51 	DEFINE_STATIC_PSCI_LIB_ARGS_V1(psci_args, bl31_warm_entrypoint);
52 
53 	/* PSCI is the only ARM Standard Service implemented */
54 	assert(svc_mask == PSCI_FID_MASK);
55 
56 	return (uintptr_t)&psci_args;
57 }
58 
59 /*******************************************************************************
60  * Simple function to initialise all BL31 helper libraries.
61  ******************************************************************************/
62 void __init bl31_lib_init(void)
63 {
64 	cm_init();
65 }
66 
67 /*******************************************************************************
68  * Setup function for BL31.
69  ******************************************************************************/
70 void bl31_setup(u_register_t arg0, u_register_t arg1, u_register_t arg2,
71 		u_register_t arg3)
72 {
73 	/* Perform early platform-specific setup */
74 	bl31_early_platform_setup2(arg0, arg1, arg2, arg3);
75 
76 	/* Perform late platform-specific setup */
77 	bl31_plat_arch_setup();
78 
79 #if CTX_INCLUDE_PAUTH_REGS
80 	/*
81 	 * Assert that the ARMv8.3-PAuth registers are present or an access
82 	 * fault will be triggered when they are being saved or restored.
83 	 */
84 	assert(is_armv8_3_pauth_present());
85 #endif /* CTX_INCLUDE_PAUTH_REGS */
86 }
87 
88 /*******************************************************************************
89  * BL31 is responsible for setting up the runtime services for the primary cpu
90  * before passing control to the bootloader or an Operating System. This
91  * function calls runtime_svc_init() which initializes all registered runtime
92  * services. The run time services would setup enough context for the core to
93  * switch to the next exception level. When this function returns, the core will
94  * switch to the programmed exception level via an ERET.
95  ******************************************************************************/
96 void bl31_main(void)
97 {
98 	NOTICE("BL31: %s\n", version_string);
99 	NOTICE("BL31: %s\n", build_message);
100 
101 	/* Perform platform setup in BL31 */
102 	bl31_platform_setup();
103 
104 	/* Initialise helper libraries */
105 	bl31_lib_init();
106 
107 #if EL3_EXCEPTION_HANDLING
108 	INFO("BL31: Initialising Exception Handling Framework\n");
109 	ehf_init();
110 #endif
111 
112 	/* Initialize the runtime services e.g. psci. */
113 	INFO("BL31: Initializing runtime services\n");
114 	runtime_svc_init();
115 
116 	/*
117 	 * All the cold boot actions on the primary cpu are done. We now need to
118 	 * decide which is the next image (BL32 or BL33) and how to execute it.
119 	 * If the SPD runtime service is present, it would want to pass control
120 	 * to BL32 first in S-EL1. In that case, SPD would have registered a
121 	 * function to initialize bl32 where it takes responsibility of entering
122 	 * S-EL1 and returning control back to bl31_main. Once this is done we
123 	 * can prepare entry into BL33 as normal.
124 	 */
125 
126 	/*
127 	 * If SPD had registered an init hook, invoke it.
128 	 */
129 	if (bl32_init != NULL) {
130 		INFO("BL31: Initializing BL32\n");
131 
132 		int32_t rc = (*bl32_init)();
133 
134 		if (rc == 0)
135 			WARN("BL31: BL32 initialization failed\n");
136 	}
137 	/*
138 	 * We are ready to enter the next EL. Prepare entry into the image
139 	 * corresponding to the desired security state after the next ERET.
140 	 */
141 	bl31_prepare_next_image_entry();
142 
143 	console_flush();
144 
145 	/*
146 	 * Perform any platform specific runtime setup prior to cold boot exit
147 	 * from BL31
148 	 */
149 	bl31_plat_runtime_setup();
150 }
151 
152 /*******************************************************************************
153  * Accessor functions to help runtime services decide which image should be
154  * executed after BL31. This is BL33 or the non-secure bootloader image by
155  * default but the Secure payload dispatcher could override this by requesting
156  * an entry into BL32 (Secure payload) first. If it does so then it should use
157  * the same API to program an entry into BL33 once BL32 initialisation is
158  * complete.
159  ******************************************************************************/
160 void bl31_set_next_image_type(uint32_t security_state)
161 {
162 	assert(sec_state_is_valid(security_state));
163 	next_image_type = security_state;
164 }
165 
166 uint32_t bl31_get_next_image_type(void)
167 {
168 	return next_image_type;
169 }
170 
171 /*******************************************************************************
172  * This function programs EL3 registers and performs other setup to enable entry
173  * into the next image after BL31 at the next ERET.
174  ******************************************************************************/
175 void __init bl31_prepare_next_image_entry(void)
176 {
177 	entry_point_info_t *next_image_info;
178 	uint32_t image_type;
179 
180 #if CTX_INCLUDE_AARCH32_REGS
181 	/*
182 	 * Ensure that the build flag to save AArch32 system registers in CPU
183 	 * context is not set for AArch64-only platforms.
184 	 */
185 	if (el_implemented(1) == EL_IMPL_A64ONLY) {
186 		ERROR("EL1 supports AArch64-only. Please set build flag "
187 				"CTX_INCLUDE_AARCH32_REGS = 0\n");
188 		panic();
189 	}
190 #endif
191 
192 	/* Determine which image to execute next */
193 	image_type = bl31_get_next_image_type();
194 
195 	/* Program EL3 registers to enable entry into the next EL */
196 	next_image_info = bl31_plat_get_next_image_ep_info(image_type);
197 	assert(next_image_info != NULL);
198 	assert(image_type == GET_SECURITY_STATE(next_image_info->h.attr));
199 
200 	INFO("BL31: Preparing for EL3 exit to %s world\n",
201 		(image_type == SECURE) ? "secure" : "normal");
202 	print_entry_point_info(next_image_info);
203 	cm_init_my_context(next_image_info);
204 	cm_prepare_el3_exit(image_type);
205 }
206 
207 /*******************************************************************************
208  * This function initializes the pointer to BL32 init function. This is expected
209  * to be called by the SPD after it finishes all its initialization
210  ******************************************************************************/
211 void bl31_register_bl32_init(int32_t (*func)(void))
212 {
213 	bl32_init = func;
214 }
215