1 /* 2 * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved. 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 */ 6 7 #include <arch.h> 8 #include <arch_helpers.h> 9 #include <assert.h> 10 #include <bl31.h> 11 #include <bl_common.h> 12 #include <console.h> 13 #include <context_mgmt.h> 14 #include <debug.h> 15 #include <ehf.h> 16 #include <platform.h> 17 #include <pmf.h> 18 #include <runtime_instr.h> 19 #include <runtime_svc.h> 20 #include <std_svc.h> 21 #include <string.h> 22 23 #if ENABLE_RUNTIME_INSTRUMENTATION 24 PMF_REGISTER_SERVICE_SMC(rt_instr_svc, PMF_RT_INSTR_SVC_ID, 25 RT_INSTR_TOTAL_IDS, PMF_STORE_ENABLE) 26 #endif 27 28 /******************************************************************************* 29 * This function pointer is used to initialise the BL32 image. It's initialized 30 * by SPD calling bl31_register_bl32_init after setting up all things necessary 31 * for SP execution. In cases where both SPD and SP are absent, or when SPD 32 * finds it impossible to execute SP, this pointer is left as NULL 33 ******************************************************************************/ 34 static int32_t (*bl32_init)(void); 35 36 /******************************************************************************* 37 * Variable to indicate whether next image to execute after BL31 is BL33 38 * (non-secure & default) or BL32 (secure). 39 ******************************************************************************/ 40 static uint32_t next_image_type = NON_SECURE; 41 42 /* 43 * Implement the ARM Standard Service function to get arguments for a 44 * particular service. 45 */ 46 uintptr_t get_arm_std_svc_args(unsigned int svc_mask) 47 { 48 /* Setup the arguments for PSCI Library */ 49 DEFINE_STATIC_PSCI_LIB_ARGS_V1(psci_args, bl31_warm_entrypoint); 50 51 /* PSCI is the only ARM Standard Service implemented */ 52 assert(svc_mask == PSCI_FID_MASK); 53 54 return (uintptr_t)&psci_args; 55 } 56 57 /******************************************************************************* 58 * Simple function to initialise all BL31 helper libraries. 59 ******************************************************************************/ 60 void bl31_lib_init(void) 61 { 62 cm_init(); 63 } 64 65 /******************************************************************************* 66 * BL31 is responsible for setting up the runtime services for the primary cpu 67 * before passing control to the bootloader or an Operating System. This 68 * function calls runtime_svc_init() which initializes all registered runtime 69 * services. The run time services would setup enough context for the core to 70 * swtich to the next exception level. When this function returns, the core will 71 * switch to the programmed exception level via. an ERET. 72 ******************************************************************************/ 73 void bl31_main(void) 74 { 75 NOTICE("BL31: %s\n", version_string); 76 NOTICE("BL31: %s\n", build_message); 77 78 /* Perform platform setup in BL31 */ 79 bl31_platform_setup(); 80 81 /* Initialise helper libraries */ 82 bl31_lib_init(); 83 84 #if EL3_EXCEPTION_HANDLING 85 INFO("BL31: Initialising Exception Handling Framework\n"); 86 ehf_init(); 87 #endif 88 89 /* Initialize the runtime services e.g. psci. */ 90 INFO("BL31: Initializing runtime services\n"); 91 runtime_svc_init(); 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("BL31: Initializing BL32\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 console_flush(); 117 118 /* 119 * Perform any platform specific runtime setup prior to cold boot exit 120 * from BL31 121 */ 122 bl31_plat_runtime_setup(); 123 } 124 125 /******************************************************************************* 126 * Accessor functions to help runtime services decide which image should be 127 * executed after BL31. This is BL33 or the non-secure bootloader image by 128 * default but the Secure payload dispatcher could override this by requesting 129 * an entry into BL32 (Secure payload) first. If it does so then it should use 130 * the same API to program an entry into BL33 once BL32 initialisation is 131 * complete. 132 ******************************************************************************/ 133 void bl31_set_next_image_type(uint32_t security_state) 134 { 135 assert(sec_state_is_valid(security_state)); 136 next_image_type = security_state; 137 } 138 139 uint32_t bl31_get_next_image_type(void) 140 { 141 return next_image_type; 142 } 143 144 /******************************************************************************* 145 * This function programs EL3 registers and performs other setup to enable entry 146 * into the next image after BL31 at the next ERET. 147 ******************************************************************************/ 148 void bl31_prepare_next_image_entry(void) 149 { 150 entry_point_info_t *next_image_info; 151 uint32_t image_type; 152 153 #if CTX_INCLUDE_AARCH32_REGS 154 /* 155 * Ensure that the build flag to save AArch32 system registers in CPU 156 * context is not set for AArch64-only platforms. 157 */ 158 if (EL_IMPLEMENTED(1) == EL_IMPL_A64ONLY) { 159 ERROR("EL1 supports AArch64-only. Please set build flag " 160 "CTX_INCLUDE_AARCH32_REGS = 0"); 161 panic(); 162 } 163 #endif 164 165 /* Determine which image to execute next */ 166 image_type = bl31_get_next_image_type(); 167 168 /* Program EL3 registers to enable entry into the next EL */ 169 next_image_info = bl31_plat_get_next_image_ep_info(image_type); 170 assert(next_image_info); 171 assert(image_type == GET_SECURITY_STATE(next_image_info->h.attr)); 172 173 INFO("BL31: Preparing for EL3 exit to %s world\n", 174 (image_type == SECURE) ? "secure" : "normal"); 175 print_entry_point_info(next_image_info); 176 cm_init_my_context(next_image_info); 177 cm_prepare_el3_exit(image_type); 178 } 179 180 /******************************************************************************* 181 * This function initializes the pointer to BL32 init function. This is expected 182 * to be called by the SPD after it finishes all its initialization 183 ******************************************************************************/ 184 void bl31_register_bl32_init(int32_t (*func)(void)) 185 { 186 bl32_init = func; 187 } 188