neobbo/src/smp.c
2026-03-04 07:15:08 +01:00

127 lines
No EOL
2.7 KiB
C

#include <assert.h>
#include <limine.h>
#include <stdbool.h>
#include <stdint.h>
#include <kprint.h>
#include <neobbo.h>
#include <arch/amd64/hal/gdt.h>
#include <smp.h>
#include <arch/amd64/hal/apic.h>
#include <arch/amd64/hal/idt.h>
#include <mm/vmm.h>
#include <mm/kmalloc.h>
#include <lock.h>
#include <arch/amd64/io.h>
#include <string.h>
extern void s_load_idt();
extern void s_load_gdt();
extern volatile struct limine_mp_request smp_request;
static cpu_state *cpus;
static cpu_state bsp_cpu;
/* Returns the CPU structure for this particular CPU */
cpu_state *get_current_cpu_state(){
return (cpu_state*)rdmsr(GSBASE);
}
cpu_state *get_bsp_cpu_state(){
return &bsp_cpu;
}
cpu_state *get_cpu_state(int id){
if(id == 0){
return &bsp_cpu;
}
return &cpus[id];
}
bool get_cpu_state_initialized(){
if(rdmsr(GSBASE) < get_kinfo()->hhdmoffset){
return false;
}
return true;
}
atomic_flag ap_init_lock = ATOMIC_FLAG_INIT;
void ap_init(struct limine_mp_info *smp_info){
acquire_spinlock(&ap_init_lock);
/* Load the GDT */
s_load_gdt();
/* Load the IDT */
s_load_idt();
/* Set the CR3 context */
extern uint64_t *kernel_page_map;
vmm_set_ctx(kernel_page_map);
asm volatile(
"movq %%cr3, %%rax\n\
movq %%rax, %%cr3\n"
: : : "rax"
);
cpu_state cpu_struct = cpus[smp_info->lapic_id];
cpu_struct.id = smp_info->lapic_id;
wrmsr(KERNELGSBASE, (uint64_t)&cpu_struct);
wrmsr(GSBASE, (uint64_t)&cpu_struct);
/* Initialize APIC & APIC timer */
ap_apic_init();
free_spinlock(&ap_init_lock);
while(!bsp_cpu.scheduler_initialized){
__builtin_ia32_pause();
}
scheduler_init();
}
void smp_init(){
struct limine_mp_response *smp_response = smp_request.response;
kprintf("smp: {d} CPUs\n", smp_response->cpu_count);
cpus = (cpu_state *)kzalloc(sizeof(cpu_state) * smp_response->cpu_count);
for(uint64_t i = 1; i < smp_response->cpu_count; i++){
/* Pointer to smp_info is passed in RDI by Limine, so no need to pass any arguments here */
smp_response->cpus[i]->goto_address = &ap_init;
}
bsp_cpu.scheduler_context = (struct context*)kzalloc(sizeof(struct context));
cpus[bsp_cpu.id] = bsp_cpu;
/* If one of the APs has halted, then halt the BSP */
extern bool kernel_killed;
assert(!kernel_killed && "Some APs failed to init!");
}
void bsp_early_init(){
assert(smp_request.response != NULL && "Failed to get SMP request");
struct limine_mp_response *smp_response = smp_request.response;
bsp_cpu.id = smp_response->cpus[0]->lapic_id;
wrmsr(KERNELGSBASE, (uint64_t)&bsp_cpu);
wrmsr(GSBASE, (uint64_t)&bsp_cpu);
}