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Diffstat (limited to '')
| -rw-r--r-- | bl1/aarch64/bl1_exceptions.S | 287 |
1 files changed, 287 insertions, 0 deletions
diff --git a/bl1/aarch64/bl1_exceptions.S b/bl1/aarch64/bl1_exceptions.S new file mode 100644 index 0000000..eaaf59a --- /dev/null +++ b/bl1/aarch64/bl1_exceptions.S @@ -0,0 +1,287 @@ +/* + * Copyright (c) 2013-2022, ARM Limited and Contributors. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <arch.h> +#include <asm_macros.S> +#include <bl1/bl1.h> +#include <common/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 +end_vector_entry SynchronousExceptionSP0 + +vector_entry IrqSP0 + mov x0, #IRQ_SP_EL0 + bl plat_report_exception + no_ret plat_panic_handler +end_vector_entry IrqSP0 + +vector_entry FiqSP0 + mov x0, #FIQ_SP_EL0 + bl plat_report_exception + no_ret plat_panic_handler +end_vector_entry FiqSP0 + +vector_entry SErrorSP0 + mov x0, #SERROR_SP_EL0 + bl plat_report_exception + no_ret plat_panic_handler +end_vector_entry 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 +end_vector_entry SynchronousExceptionSPx + +vector_entry IrqSPx + mov x0, #IRQ_SP_ELX + bl plat_report_exception + no_ret plat_panic_handler +end_vector_entry IrqSPx + +vector_entry FiqSPx + mov x0, #FIQ_SP_ELX + bl plat_report_exception + no_ret plat_panic_handler +end_vector_entry FiqSPx + +vector_entry SErrorSPx + mov x0, #SERROR_SP_ELX + bl plat_report_exception + no_ret plat_panic_handler +end_vector_entry 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 +end_vector_entry SynchronousExceptionA64 + +vector_entry IrqA64 + mov x0, #IRQ_AARCH64 + bl plat_report_exception + no_ret plat_panic_handler +end_vector_entry IrqA64 + +vector_entry FiqA64 + mov x0, #FIQ_AARCH64 + bl plat_report_exception + no_ret plat_panic_handler +end_vector_entry FiqA64 + +vector_entry SErrorA64 + mov x0, #SERROR_AARCH64 + bl plat_report_exception + no_ret plat_panic_handler +end_vector_entry SErrorA64 + + /* ----------------------------------------------------- + * Lower EL using AArch32 : 0x600 - 0x800 + * ----------------------------------------------------- + */ +vector_entry SynchronousExceptionA32 + mov x0, #SYNC_EXCEPTION_AARCH32 + bl plat_report_exception + no_ret plat_panic_handler +end_vector_entry SynchronousExceptionA32 + +vector_entry IrqA32 + mov x0, #IRQ_AARCH32 + bl plat_report_exception + no_ret plat_panic_handler +end_vector_entry IrqA32 + +vector_entry FiqA32 + mov x0, #FIQ_AARCH32 + bl plat_report_exception + no_ret plat_panic_handler +end_vector_entry FiqA32 + +vector_entry SErrorA32 + mov x0, #SERROR_AARCH32 + bl plat_report_exception + no_ret plat_panic_handler +end_vector_entry 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, #MODE_SP_EL0 + 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 + dsb ish /* ERET implies ISB, so it is not needed here */ + +#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)] + exception_return +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 x0-x29 and ARMv8.3-PAuth (if enabled) registers. + * Save PMCR_EL0 and disable Cycle Counter. + * TODO: Revisit to store only SMCCC specified registers. + * ----------------------------------------------------- + */ + bl prepare_el3_entry + +#if ENABLE_PAUTH + /* ----------------------------------------------------- + * Load and program stored APIAKey firmware key. + * Re-enable pointer authentication in EL3, as it was + * disabled before jumping to the next boot image. + * ----------------------------------------------------- + */ + bl pauth_load_bl1_apiakey_enable +#endif + /* ----------------------------------------------------- + * 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, #MODE_SP_EL0 + 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 |