kernel/start.c


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#include "kernel/lib.h"
#include "kernel/riscv.h"
#include "kernel/kalloc.h"
#include "kernel/vm.h"
#include "kernel/cpu.h"

Cpu cpus[MAX_CPU];

extern uint32_t _bss_start;
extern uint32_t _bss_end;
extern uint32_t _ram_end;

void kstrap()
{
    panic("kstrap");
}

void kstart()
{
    kalloc_init();
    kvm_init();
   
    panic("kstart: end");
}

void kinit()
{
    // @Todo Initialize CPUs
    Cpu null_cpu = {0};
    cpus[0] = null_cpu;

    // Clear the BSS section
    for (uint32_t* ptr = &_bss_start; ptr < &_bss_end; ++ptr)
    {
        *ptr = 0U;
    }

    w_mideleg(0xFFFF);
    w_medeleg(0xFFFF);

    w_sstatus(SSTATUS_SPIE | SSTATUS_SPP_S);
    w_sie(SIE_SEIE);
    w_sepc(&kstart);
    w_stvec(&kstrap);

    w_pmpcfg0(PMPCFG_RW | PMPCFG_X | PMPCFG_TOR);
    w_pmpaddr0(((uint32_t)&_ram_end) >> PMPADDR_SHIFT);

    __asm__ volatile("sret");
}