1 /* 2 * Copyright (c) 2013-2020, 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 #ifdef SUPPORT_UNKNOWN_MPID 45 /* 46 * Flag to know whether an unsupported MPID has been detected. To avoid having it 47 * landing on the .bss section, it is initialized to a non-zero value, this way 48 * we avoid potential WAW hazards during system bring up. 49 * */ 50 volatile uint32_t unsupported_mpid_flag = 1; 51 #endif 52 53 /* 54 * Implement the ARM Standard Service function to get arguments for a 55 * particular service. 56 */ 57 uintptr_t get_arm_std_svc_args(unsigned int svc_mask) 58 { 59 /* Setup the arguments for PSCI Library */ 60 DEFINE_STATIC_PSCI_LIB_ARGS_V1(psci_args, bl31_warm_entrypoint); 61 62 /* PSCI is the only ARM Standard Service implemented */ 63 assert(svc_mask == PSCI_FID_MASK); 64 65 return (uintptr_t)&psci_args; 66 } 67 68 /******************************************************************************* 69 * Simple function to initialise all BL31 helper libraries. 70 ******************************************************************************/ 71 void __init bl31_lib_init(void) 72 { 73 cm_init(); 74 } 75 76 /******************************************************************************* 77 * Setup function for BL31. 78 ******************************************************************************/ 79 void bl31_setup(u_register_t arg0, u_register_t arg1, u_register_t arg2, 80 u_register_t arg3) 81 { 82 /* Perform early platform-specific setup */ 83 bl31_early_platform_setup2(arg0, arg1, arg2, arg3); 84 85 /* Perform late platform-specific setup */ 86 bl31_plat_arch_setup(); 87 88 #if ENABLE_FEAT_HCX 89 /* 90 * Assert that FEAT_HCX is supported on this system, without this check 91 * an exception would occur during context save/restore if enabled but 92 * not supported. 93 */ 94 assert(is_feat_hcx_present()); 95 #endif /* ENABLE_FEAT_HCX */ 96 97 #if CTX_INCLUDE_PAUTH_REGS 98 /* 99 * Assert that the ARMv8.3-PAuth registers are present or an access 100 * fault will be triggered when they are being saved or restored. 101 */ 102 assert(is_armv8_3_pauth_present()); 103 #endif /* CTX_INCLUDE_PAUTH_REGS */ 104 } 105 106 /******************************************************************************* 107 * BL31 is responsible for setting up the runtime services for the primary cpu 108 * before passing control to the bootloader or an Operating System. This 109 * function calls runtime_svc_init() which initializes all registered runtime 110 * services. The run time services would setup enough context for the core to 111 * switch to the next exception level. When this function returns, the core will 112 * switch to the programmed exception level via an ERET. 113 ******************************************************************************/ 114 void bl31_main(void) 115 { 116 NOTICE("BL31: %s\n", version_string); 117 NOTICE("BL31: %s\n", build_message); 118 119 #ifdef SUPPORT_UNKNOWN_MPID 120 if (unsupported_mpid_flag == 0) { 121 NOTICE("Unsupported MPID detected!\n"); 122 } 123 #endif 124 125 /* Perform platform setup in BL31 */ 126 bl31_platform_setup(); 127 128 /* Initialise helper libraries */ 129 bl31_lib_init(); 130 131 #if EL3_EXCEPTION_HANDLING 132 INFO("BL31: Initialising Exception Handling Framework\n"); 133 ehf_init(); 134 #endif 135 136 /* Initialize the runtime services e.g. psci. */ 137 INFO("BL31: Initializing runtime services\n"); 138 runtime_svc_init(); 139 140 /* 141 * All the cold boot actions on the primary cpu are done. We now need to 142 * decide which is the next image (BL32 or BL33) and how to execute it. 143 * If the SPD runtime service is present, it would want to pass control 144 * to BL32 first in S-EL1. In that case, SPD would have registered a 145 * function to initialize bl32 where it takes responsibility of entering 146 * S-EL1 and returning control back to bl31_main. Once this is done we 147 * can prepare entry into BL33 as normal. 148 */ 149 150 /* 151 * If SPD had registered an init hook, invoke it. 152 */ 153 if (bl32_init != NULL) { 154 INFO("BL31: Initializing BL32\n"); 155 156 int32_t rc = (*bl32_init)(); 157 158 if (rc == 0) 159 WARN("BL31: BL32 initialization failed\n"); 160 } 161 /* 162 * We are ready to enter the next EL. Prepare entry into the image 163 * corresponding to the desired security state after the next ERET. 164 */ 165 bl31_prepare_next_image_entry(); 166 167 console_flush(); 168 169 /* 170 * Perform any platform specific runtime setup prior to cold boot exit 171 * from BL31 172 */ 173 bl31_plat_runtime_setup(); 174 } 175 176 /******************************************************************************* 177 * Accessor functions to help runtime services decide which image should be 178 * executed after BL31. This is BL33 or the non-secure bootloader image by 179 * default but the Secure payload dispatcher could override this by requesting 180 * an entry into BL32 (Secure payload) first. If it does so then it should use 181 * the same API to program an entry into BL33 once BL32 initialisation is 182 * complete. 183 ******************************************************************************/ 184 void bl31_set_next_image_type(uint32_t security_state) 185 { 186 assert(sec_state_is_valid(security_state)); 187 next_image_type = security_state; 188 } 189 190 uint32_t bl31_get_next_image_type(void) 191 { 192 return next_image_type; 193 } 194 195 /******************************************************************************* 196 * This function programs EL3 registers and performs other setup to enable entry 197 * into the next image after BL31 at the next ERET. 198 ******************************************************************************/ 199 void __init bl31_prepare_next_image_entry(void) 200 { 201 entry_point_info_t *next_image_info; 202 uint32_t image_type; 203 204 #if CTX_INCLUDE_AARCH32_REGS 205 /* 206 * Ensure that the build flag to save AArch32 system registers in CPU 207 * context is not set for AArch64-only platforms. 208 */ 209 if (el_implemented(1) == EL_IMPL_A64ONLY) { 210 ERROR("EL1 supports AArch64-only. Please set build flag " 211 "CTX_INCLUDE_AARCH32_REGS = 0\n"); 212 panic(); 213 } 214 #endif 215 216 /* Determine which image to execute next */ 217 image_type = bl31_get_next_image_type(); 218 219 /* Program EL3 registers to enable entry into the next EL */ 220 next_image_info = bl31_plat_get_next_image_ep_info(image_type); 221 assert(next_image_info != NULL); 222 assert(image_type == GET_SECURITY_STATE(next_image_info->h.attr)); 223 224 INFO("BL31: Preparing for EL3 exit to %s world\n", 225 (image_type == SECURE) ? "secure" : "normal"); 226 print_entry_point_info(next_image_info); 227 cm_init_my_context(next_image_info); 228 cm_prepare_el3_exit(image_type); 229 } 230 231 /******************************************************************************* 232 * This function initializes the pointer to BL32 init function. This is expected 233 * to be called by the SPD after it finishes all its initialization 234 ******************************************************************************/ 235 void bl31_register_bl32_init(int32_t (*func)(void)) 236 { 237 bl32_init = func; 238 } 239