diff options
Diffstat (limited to '')
-rw-r--r-- | bl2u/aarch64/bl2u_entrypoint.S | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/bl2u/aarch64/bl2u_entrypoint.S b/bl2u/aarch64/bl2u_entrypoint.S new file mode 100644 index 0000000..15978b6 --- /dev/null +++ b/bl2u/aarch64/bl2u_entrypoint.S @@ -0,0 +1,129 @@ +/* + * Copyright (c) 2015-2021, ARM Limited and Contributors. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <arch.h> +#include <asm_macros.S> +#include <common/bl_common.h> + + .globl bl2u_entrypoint + + +func bl2u_entrypoint + /*--------------------------------------------- + * Store the extents of the tzram available to + * BL2U and other platform specific information + * for future use. x0 is currently not used. + * --------------------------------------------- + */ + mov x20, x1 + mov x21, x2 + + /* --------------------------------------------- + * Set the exception vector to something sane. + * --------------------------------------------- + */ + adr x0, early_exceptions + msr vbar_el1, x0 + isb + + /* --------------------------------------------- + * Enable the SError interrupt now that the + * exception vectors have been setup. + * --------------------------------------------- + */ + msr daifclr, #DAIF_ABT_BIT + + /* --------------------------------------------- + * Enable the instruction cache, stack pointer + * and data access alignment checks and disable + * speculative loads. + * --------------------------------------------- + */ + mov x1, #(SCTLR_I_BIT | SCTLR_A_BIT | SCTLR_SA_BIT) + mrs x0, sctlr_el1 + orr x0, x0, x1 + bic x0, x0, #SCTLR_DSSBS_BIT + msr sctlr_el1, x0 + isb + + /* --------------------------------------------- + * Invalidate the RW memory used by the BL2U + * image. This includes the data and NOBITS + * sections. This is done to safeguard against + * possible corruption of this memory by dirty + * cache lines in a system cache as a result of + * use by an earlier boot loader stage. + * --------------------------------------------- + */ + adr x0, __RW_START__ + adr x1, __RW_END__ + sub x1, x1, x0 + bl inv_dcache_range + + /* --------------------------------------------- + * Zero out NOBITS sections. There are 2 of them: + * - the .bss section; + * - the coherent memory section. + * --------------------------------------------- + */ + adrp x0, __BSS_START__ + add x0, x0, :lo12:__BSS_START__ + adrp x1, __BSS_END__ + add x1, x1, :lo12:__BSS_END__ + sub x1, x1, x0 + bl zeromem + + /* -------------------------------------------- + * Allocate a stack whose memory will be marked + * as Normal-IS-WBWA when the MMU is enabled. + * There is no risk of reading stale stack + * memory after enabling the MMU as only the + * primary cpu is running at the moment. + * -------------------------------------------- + */ + bl plat_set_my_stack + + /* --------------------------------------------- + * Initialize the stack protector canary before + * any C code is called. + * --------------------------------------------- + */ +#if STACK_PROTECTOR_ENABLED + bl update_stack_protector_canary +#endif + + /* --------------------------------------------- + * Perform early platform setup & platform + * specific early arch. setup e.g. mmu setup + * --------------------------------------------- + */ + mov x0, x20 + mov x1, x21 + bl bl2u_early_platform_setup + bl bl2u_plat_arch_setup + +#if ENABLE_PAUTH + /* --------------------------------------------- + * Program APIAKey_EL1 + * and enable pointer authentication. + * --------------------------------------------- + */ + bl pauth_init_enable_el1 +#endif + + /* --------------------------------------------- + * Jump to bl2u_main function. + * --------------------------------------------- + */ + bl bl2u_main + + /* --------------------------------------------- + * Should never reach this point. + * --------------------------------------------- + */ + no_ret plat_panic_handler + +endfunc bl2u_entrypoint |