SquidgeOS/src/kernel/interrupts.c

#include <stddef.h>
#include <stdint.h>
#include <drivers/uart.h>
#include <syscon/syscon.h>
#include "memory.h"

void kpanic(const char *reason)
{
    kputs("\n!!! PANIC !!!\n");
    kputs(reason);
    kputs("\n!!! PANIC !!!\n");
    poweroff();
}

void kpanic_force()
{
    kprint("\n!!! FORCE PANIC !!!\n");

    // 'ebreak' is the standard RISC-V way to trigger a debug trap.
    __asm__ volatile("ebreak");

    kprint("Force panic falled. Power off. \n");
    poweroff();

    kprint("Force panic falled. Power off failed. sleep until interupt. \n");
    while (1)
    {
        __asm__ volatile("wfi");
    }
}

void handle_trap()
{
    kprint("\n!!! HARDWARE EXCEPTION DETECTED !!!\n");

    // Read the 'mcause' register to see WHY we trapped
    unsigned long cause;
    __asm__ volatile("csrr %0, mcause" : "=r"(cause));

    // fault address (if applicable)
    uintptr_t mtval;
    asm volatile("csrr %0, mtval" : "=r"(mtval));

    switch (cause)
    {
    case 0:
        kprint("Reason: Instruction Address Misaligned\n");
        break;
    case 1:
        kprint("Reason: Instruction Access Fault\n");
        break;
    case 2:
        kprint("Reason: Illegal Instruction\n");
        break;
    case 3:
        kprint("Reason: Breakpoint (ebreak)\n");
        break;
    case 4:
        kprint("Reason: Load Address Misaligned\n");
        break;
    case 5:
        kprint("Reason: Load Access Fault\n");
        break;
    case 6:
        kprint("Reason: Store/AMO Address Misaligned\n");
        break;
    case 7:
        kprint("Reason: Store/AMO Access Fault\n");
        break;
    default:
        kprintf("Reason: Unknown Exception Code %d\n", cause);
    }
    kprintf("Faulting Address (if applicable): %x\n", mtval);

    heap_stats();

    poweroff();
}