1 /* 2 * Copyright (c) 2013-2017, 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 <string.h> 21 22 #if ENABLE_RUNTIME_INSTRUMENTATION 23 PMF_REGISTER_SERVICE_SMC(rt_instr_svc, PMF_RT_INSTR_SVC_ID, 24 RT_INSTR_TOTAL_IDS, PMF_STORE_ENABLE) 25 #endif 26 27 /******************************************************************************* 28 * This function pointer is used to initialise the BL32 image. It's initialized 29 * by SPD calling bl31_register_bl32_init after setting up all things necessary 30 * for SP execution. In cases where both SPD and SP are absent, or when SPD 31 * finds it impossible to execute SP, this pointer is left as NULL 32 ******************************************************************************/ 33 static int32_t (*bl32_init)(void); 34 35 /******************************************************************************* 36 * Variable to indicate whether next image to execute after BL31 is BL33 37 * (non-secure & default) or BL32 (secure). 38 ******************************************************************************/ 39 static uint32_t next_image_type = NON_SECURE; 40 41 /* 42 * Implement the ARM Standard Service function to get arguments for a 43 * particular service. 44 */ 45 uintptr_t get_arm_std_svc_args(unsigned int svc_mask) 46 { 47 /* Setup the arguments for PSCI Library */ 48 DEFINE_STATIC_PSCI_LIB_ARGS_V1(psci_args, bl31_warm_entrypoint); 49 50 /* PSCI is the only ARM Standard Service implemented */ 51 assert(svc_mask == PSCI_FID_MASK); 52 53 return (uintptr_t)&psci_args; 54 } 55 56 /******************************************************************************* 57 * Simple function to initialise all BL31 helper libraries. 58 ******************************************************************************/ 59 void bl31_lib_init(void) 60 { 61 cm_init(); 62 } 63 64 /******************************************************************************* 65 * BL31 is responsible for setting up the runtime services for the primary cpu 66 * before passing control to the bootloader or an Operating System. This 67 * function calls runtime_svc_init() which initializes all registered runtime 68 * services. The run time services would setup enough context for the core to 69 * swtich to the next exception level. When this function returns, the core will 70 * switch to the programmed exception level via. an ERET. 71 ******************************************************************************/ 72 void bl31_main(void) 73 { 74 NOTICE("BL31: %s\n", version_string); 75 NOTICE("BL31: %s\n", build_message); 76 77 /* Perform platform setup in BL31 */ 78 bl31_platform_setup(); 79 80 /* Initialise helper libraries */ 81 bl31_lib_init(); 82 83 #if EL3_EXCEPTION_HANDLING 84 INFO("BL31: Initialising Exception Handling Framework\n"); 85 ehf_init(); 86 #endif 87 88 /* Initialize the runtime services e.g. psci. */ 89 INFO("BL31: Initializing runtime services\n"); 90 runtime_svc_init(); 91 92 /* 93 * All the cold boot actions on the primary cpu are done. We now need to 94 * decide which is the next image (BL32 or BL33) and how to execute it. 95 * If the SPD runtime service is present, it would want to pass control 96 * to BL32 first in S-EL1. In that case, SPD would have registered a 97 * function to intialize bl32 where it takes responsibility of entering 98 * S-EL1 and returning control back to bl31_main. Once this is done we 99 * can prepare entry into BL33 as normal. 100 */ 101 102 /* 103 * If SPD had registerd an init hook, invoke it. 104 */ 105 if (bl32_init) { 106 INFO("BL31: Initializing BL32\n"); 107 (*bl32_init)(); 108 } 109 /* 110 * We are ready to enter the next EL. Prepare entry into the image 111 * corresponding to the desired security state after the next ERET. 112 */ 113 bl31_prepare_next_image_entry(); 114 115 console_flush(); 116 117 /* 118 * Perform any platform specific runtime setup prior to cold boot exit 119 * from BL31 120 */ 121 bl31_plat_runtime_setup(); 122 } 123 124 /******************************************************************************* 125 * Accessor functions to help runtime services decide which image should be 126 * executed after BL31. This is BL33 or the non-secure bootloader image by 127 * default but the Secure payload dispatcher could override this by requesting 128 * an entry into BL32 (Secure payload) first. If it does so then it should use 129 * the same API to program an entry into BL33 once BL32 initialisation is 130 * complete. 131 ******************************************************************************/ 132 void bl31_set_next_image_type(uint32_t security_state) 133 { 134 assert(sec_state_is_valid(security_state)); 135 next_image_type = security_state; 136 } 137 138 uint32_t bl31_get_next_image_type(void) 139 { 140 return next_image_type; 141 } 142 143 /******************************************************************************* 144 * This function programs EL3 registers and performs other setup to enable entry 145 * into the next image after BL31 at the next ERET. 146 ******************************************************************************/ 147 void bl31_prepare_next_image_entry(void) 148 { 149 entry_point_info_t *next_image_info; 150 uint32_t image_type; 151 152 #if CTX_INCLUDE_AARCH32_REGS 153 /* 154 * Ensure that the build flag to save AArch32 system registers in CPU 155 * context is not set for AArch64-only platforms. 156 */ 157 if (EL_IMPLEMENTED(1) == EL_IMPL_A64ONLY) { 158 ERROR("EL1 supports AArch64-only. Please set build flag " 159 "CTX_INCLUDE_AARCH32_REGS = 0"); 160 panic(); 161 } 162 #endif 163 164 /* Determine which image to execute next */ 165 image_type = bl31_get_next_image_type(); 166 167 /* Program EL3 registers to enable entry into the next EL */ 168 next_image_info = bl31_plat_get_next_image_ep_info(image_type); 169 assert(next_image_info); 170 assert(image_type == GET_SECURITY_STATE(next_image_info->h.attr)); 171 172 INFO("BL31: Preparing for EL3 exit to %s world\n", 173 (image_type == SECURE) ? "secure" : "normal"); 174 print_entry_point_info(next_image_info); 175 cm_init_my_context(next_image_info); 176 cm_prepare_el3_exit(image_type); 177 } 178 179 /******************************************************************************* 180 * This function initializes the pointer to BL32 init function. This is expected 181 * to be called by the SPD after it finishes all its initialization 182 ******************************************************************************/ 183 void bl31_register_bl32_init(int32_t (*func)(void)) 184 { 185 bl32_init = func; 186 } 187