| /* |
| * Copyright 2020, Data61, CSIRO (ABN 41 687 119 230) |
| * |
| * SPDX-License-Identifier: GPL-2.0-only |
| */ |
| |
| |
| #include <autoconf.h> |
| #include <elfloader/gen_config.h> |
| |
| #ifndef CONFIG_ARM_MONITOR_HOOK |
| #error This file is for CONFIG_ARM_MONITOR_HOOK only |
| #endif |
| |
| #define VECTOR_BASE 0xa7f00000 |
| #define STACK_TOP (VECTOR_BASE + (1 << 20) - 0x10) |
| |
| /* vector table for monitor mode |
| * 0x00: not used |
| * 0x04: not used |
| * 0x08: secure monitor call |
| * 0x0c: prefetch abort |
| * 0x10: data abort |
| * 0x14: not used |
| * 0x18: IRQ interrupt |
| * 0x1c: FIQ interrupt |
| */ |
| |
| .global arm_monitor_vector |
| .global arm_monitor_vector_end |
| .global smc_handler |
| .global smc_halt |
| |
| /* pc contains the current instruction + 8 bytes |
| * use pc-relative addressing so we can copy the |
| * table. only the offset 0x08 is set up to call |
| * smc_handler, other offsets halt the system. |
| */ |
| |
| arm_monitor_vector: |
| ldr pc, [pc, #28] |
| ldr pc, [pc, #24] |
| ldr pc, [pc, #16] |
| ldr pc, [pc, #16] |
| ldr pc, [pc, #12] |
| ldr pc, [pc, #8] |
| ldr pc, [pc, #4] |
| ldr pc, [pc, #0] |
| |
| smc_handler_addr: |
| .word VECTOR_BASE + (smc_handler - arm_monitor_vector) |
| smc_halt_addr: |
| .word VECTOR_BASE + (smc_halt - arm_monitor_vector) |
| smc_stack: |
| .word STACK_TOP |
| |
| /* r0: the start physical address for the code that the |
| * caller wants to execute in monitor mode. I know, a huge |
| * security hole. WARNING: the code to be executed should |
| * not reference memory locations !!! |
| */ |
| smc_handler: |
| /* always have a valid stack */ |
| ldr sp, [pc, #-12] |
| push {lr} |
| blx r0 |
| mrc p15, 0, r12, c1, c1, 0 |
| /* set the NS bit */ |
| orr r12, r12, #1 |
| mcr p15, 0, r12, c1, c1, 0 |
| pop {lr} |
| movs pc, lr |
| |
| /* for all other exceptions, just hang */ |
| smc_halt: |
| ldr pc, [pc, #-48] |
| |
| arm_monitor_vector_end: |
