1 /* 2 * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved. 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 */ 6 7 #include <arch.h> 8 #include <asm_macros.S> 9 #include <bl_common.h> 10 11 12 .globl bl2u_entrypoint 13 14 15 func bl2u_entrypoint 16 /*--------------------------------------------- 17 * Store the extents of the tzram available to 18 * BL2U and other platform specific information 19 * for future use. x0 is currently not used. 20 * --------------------------------------------- 21 */ 22 mov x20, x1 23 mov x21, x2 24 25 /* --------------------------------------------- 26 * Set the exception vector to something sane. 27 * --------------------------------------------- 28 */ 29 adr x0, early_exceptions 30 msr vbar_el1, x0 31 isb 32 33 /* --------------------------------------------- 34 * Enable the SError interrupt now that the 35 * exception vectors have been setup. 36 * --------------------------------------------- 37 */ 38 msr daifclr, #DAIF_ABT_BIT 39 40 /* --------------------------------------------- 41 * Enable the instruction cache, stack pointer 42 * and data access alignment checks 43 * --------------------------------------------- 44 */ 45 mov x1, #(SCTLR_I_BIT | SCTLR_A_BIT | SCTLR_SA_BIT) 46 mrs x0, sctlr_el1 47 orr x0, x0, x1 48 msr sctlr_el1, x0 49 isb 50 51 /* --------------------------------------------- 52 * Invalidate the RW memory used by the BL2U 53 * image. This includes the data and NOBITS 54 * sections. This is done to safeguard against 55 * possible corruption of this memory by dirty 56 * cache lines in a system cache as a result of 57 * use by an earlier boot loader stage. 58 * --------------------------------------------- 59 */ 60 adr x0, __RW_START__ 61 adr x1, __RW_END__ 62 sub x1, x1, x0 63 bl inv_dcache_range 64 65 /* --------------------------------------------- 66 * Zero out NOBITS sections. There are 2 of them: 67 * - the .bss section; 68 * - the coherent memory section. 69 * --------------------------------------------- 70 */ 71 ldr x0, =__BSS_START__ 72 ldr x1, =__BSS_SIZE__ 73 bl zeromem 74 75 /* -------------------------------------------- 76 * Allocate a stack whose memory will be marked 77 * as Normal-IS-WBWA when the MMU is enabled. 78 * There is no risk of reading stale stack 79 * memory after enabling the MMU as only the 80 * primary cpu is running at the moment. 81 * -------------------------------------------- 82 */ 83 bl plat_set_my_stack 84 85 /* --------------------------------------------- 86 * Initialize the stack protector canary before 87 * any C code is called. 88 * --------------------------------------------- 89 */ 90 #if STACK_PROTECTOR_ENABLED 91 bl update_stack_protector_canary 92 #endif 93 94 /* --------------------------------------------- 95 * Perform early platform setup & platform 96 * specific early arch. setup e.g. mmu setup 97 * --------------------------------------------- 98 */ 99 mov x0, x20 100 mov x1, x21 101 bl bl2u_early_platform_setup 102 bl bl2u_plat_arch_setup 103 104 /* --------------------------------------------- 105 * Jump to bl2u_main function. 106 * --------------------------------------------- 107 */ 108 bl bl2u_main 109 110 /* --------------------------------------------- 111 * Should never reach this point. 112 * --------------------------------------------- 113 */ 114 no_ret plat_panic_handler 115 116 endfunc bl2u_entrypoint 117
