/* * Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved. * * SPDX-License-Identifier: BSD-3-Clause */ #include <arch.h> #include <asm_macros.S> #include <bl1.h> #include <bl_common.h> #include <context.h> /* ----------------------------------------------------------------------------- * Very simple stackless exception handlers used by BL1. * ----------------------------------------------------------------------------- */ .globl bl1_exceptions vector_base bl1_exceptions /* ----------------------------------------------------- * Current EL with SP0 : 0x0 - 0x200 * ----------------------------------------------------- */ vector_entry SynchronousExceptionSP0 mov x0, #SYNC_EXCEPTION_SP_EL0 bl plat_report_exception no_ret plat_panic_handler check_vector_size SynchronousExceptionSP0 vector_entry IrqSP0 mov x0, #IRQ_SP_EL0 bl plat_report_exception no_ret plat_panic_handler check_vector_size IrqSP0 vector_entry FiqSP0 mov x0, #FIQ_SP_EL0 bl plat_report_exception no_ret plat_panic_handler check_vector_size FiqSP0 vector_entry SErrorSP0 mov x0, #SERROR_SP_EL0 bl plat_report_exception no_ret plat_panic_handler check_vector_size SErrorSP0 /* ----------------------------------------------------- * Current EL with SPx: 0x200 - 0x400 * ----------------------------------------------------- */ vector_entry SynchronousExceptionSPx mov x0, #SYNC_EXCEPTION_SP_ELX bl plat_report_exception no_ret plat_panic_handler check_vector_size SynchronousExceptionSPx vector_entry IrqSPx mov x0, #IRQ_SP_ELX bl plat_report_exception no_ret plat_panic_handler check_vector_size IrqSPx vector_entry FiqSPx mov x0, #FIQ_SP_ELX bl plat_report_exception no_ret plat_panic_handler check_vector_size FiqSPx vector_entry SErrorSPx mov x0, #SERROR_SP_ELX bl plat_report_exception no_ret plat_panic_handler check_vector_size SErrorSPx /* ----------------------------------------------------- * Lower EL using AArch64 : 0x400 - 0x600 * ----------------------------------------------------- */ vector_entry SynchronousExceptionA64 /* Enable the SError interrupt */ msr daifclr, #DAIF_ABT_BIT str x30, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR] /* Expect only SMC exceptions */ mrs x30, esr_el3 ubfx x30, x30, #ESR_EC_SHIFT, #ESR_EC_LENGTH cmp x30, #EC_AARCH64_SMC b.ne unexpected_sync_exception b smc_handler64 check_vector_size SynchronousExceptionA64 vector_entry IrqA64 mov x0, #IRQ_AARCH64 bl plat_report_exception no_ret plat_panic_handler check_vector_size IrqA64 vector_entry FiqA64 mov x0, #FIQ_AARCH64 bl plat_report_exception no_ret plat_panic_handler check_vector_size FiqA64 vector_entry SErrorA64 mov x0, #SERROR_AARCH64 bl plat_report_exception no_ret plat_panic_handler check_vector_size SErrorA64 /* ----------------------------------------------------- * Lower EL using AArch32 : 0x600 - 0x800 * ----------------------------------------------------- */ vector_entry SynchronousExceptionA32 mov x0, #SYNC_EXCEPTION_AARCH32 bl plat_report_exception no_ret plat_panic_handler check_vector_size SynchronousExceptionA32 vector_entry IrqA32 mov x0, #IRQ_AARCH32 bl plat_report_exception no_ret plat_panic_handler check_vector_size IrqA32 vector_entry FiqA32 mov x0, #FIQ_AARCH32 bl plat_report_exception no_ret plat_panic_handler check_vector_size FiqA32 vector_entry SErrorA32 mov x0, #SERROR_AARCH32 bl plat_report_exception no_ret plat_panic_handler check_vector_size SErrorA32 func smc_handler64 /* ---------------------------------------------- * Detect if this is a RUN_IMAGE or other SMC. * ---------------------------------------------- */ mov x30, #BL1_SMC_RUN_IMAGE cmp x30, x0 b.ne smc_handler /* ------------------------------------------------ * Make sure only Secure world reaches here. * ------------------------------------------------ */ mrs x30, scr_el3 tst x30, #SCR_NS_BIT b.ne unexpected_sync_exception /* ---------------------------------------------- * Handling RUN_IMAGE SMC. First switch back to * SP_EL0 for the C runtime stack. * ---------------------------------------------- */ ldr x30, [sp, #CTX_EL3STATE_OFFSET + CTX_RUNTIME_SP] msr spsel, #0 mov sp, x30 /* --------------------------------------------------------------------- * Pass EL3 control to next BL image. * Here it expects X1 with the address of a entry_point_info_t * structure describing the next BL image entrypoint. * --------------------------------------------------------------------- */ mov x20, x1 mov x0, x20 bl bl1_print_next_bl_ep_info ldp x0, x1, [x20, #ENTRY_POINT_INFO_PC_OFFSET] msr elr_el3, x0 msr spsr_el3, x1 ubfx x0, x1, #MODE_EL_SHIFT, #2 cmp x0, #MODE_EL3 b.ne unexpected_sync_exception bl disable_mmu_icache_el3 tlbi alle3 #if SPIN_ON_BL1_EXIT bl print_debug_loop_message debug_loop: b debug_loop #endif mov x0, x20 bl bl1_plat_prepare_exit ldp x6, x7, [x20, #(ENTRY_POINT_INFO_ARGS_OFFSET + 0x30)] ldp x4, x5, [x20, #(ENTRY_POINT_INFO_ARGS_OFFSET + 0x20)] ldp x2, x3, [x20, #(ENTRY_POINT_INFO_ARGS_OFFSET + 0x10)] ldp x0, x1, [x20, #(ENTRY_POINT_INFO_ARGS_OFFSET + 0x0)] eret endfunc smc_handler64 unexpected_sync_exception: mov x0, #SYNC_EXCEPTION_AARCH64 bl plat_report_exception no_ret plat_panic_handler /* ----------------------------------------------------- * Save Secure/Normal world context and jump to * BL1 SMC handler. * ----------------------------------------------------- */ smc_handler: /* ----------------------------------------------------- * Save the GP registers x0-x29. * TODO: Revisit to store only SMCC specified registers. * ----------------------------------------------------- */ bl save_gp_registers /* ----------------------------------------------------- * Populate the parameters for the SMC handler. We * already have x0-x4 in place. x5 will point to a * cookie (not used now). x6 will point to the context * structure (SP_EL3) and x7 will contain flags we need * to pass to the handler. * ----------------------------------------------------- */ mov x5, xzr mov x6, sp /* ----------------------------------------------------- * Restore the saved C runtime stack value which will * become the new SP_EL0 i.e. EL3 runtime stack. It was * saved in the 'cpu_context' structure prior to the last * ERET from EL3. * ----------------------------------------------------- */ ldr x12, [x6, #CTX_EL3STATE_OFFSET + CTX_RUNTIME_SP] /* --------------------------------------------- * Switch back to SP_EL0 for the C runtime stack. * --------------------------------------------- */ msr spsel, #0 mov sp, x12 /* ----------------------------------------------------- * Save the SPSR_EL3, ELR_EL3, & SCR_EL3 in case there * is a world switch during SMC handling. * ----------------------------------------------------- */ mrs x16, spsr_el3 mrs x17, elr_el3 mrs x18, scr_el3 stp x16, x17, [x6, #CTX_EL3STATE_OFFSET + CTX_SPSR_EL3] str x18, [x6, #CTX_EL3STATE_OFFSET + CTX_SCR_EL3] /* Copy SCR_EL3.NS bit to the flag to indicate caller's security */ bfi x7, x18, #0, #1 /* ----------------------------------------------------- * Go to BL1 SMC handler. * ----------------------------------------------------- */ bl bl1_smc_handler /* ----------------------------------------------------- * Do the transition to next BL image. * ----------------------------------------------------- */ b el3_exit