| // Copyright 2025 Google LLC |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #include <cstdint> |
| |
| extern "C" { |
| |
| void isr_wrapper(void); |
| __attribute__((naked)) void isr_wrapper() { |
| asm volatile( |
| "csrr t0, mepc \n" |
| "addi t0, t0, 2 \n" |
| "csrw mepc, t0 \n" |
| "mret \n"); |
| } |
| void bad_isr(void); |
| __attribute__((naked)) void bad_isr() { asm volatile("ebreak \n"); } |
| |
| __attribute__((naked, aligned(256))) void isr_vector_table() { |
| asm volatile( |
| "j isr_wrapper \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n" |
| "j bad_isr \n"); |
| } |
| |
| int main(int argc, char** argv) { |
| asm volatile("csrw mtvec, %0" ::"rK"((uint32_t)(&isr_vector_table))); |
| asm volatile("ecall"); |
| return 0; |
| } |
| |
| } // extern "C" |
