#include "kernel.h"
#include "log.h"
#include "smp.h"

#include <stdint.h>
#include "gdt.h"
#include "mem.h"
#include "vmem.h"
#include "interrupts.h"
#include "kmalloc.h"
#include "spinlock.h"
#include "asm_x86.h"
#include "asm_pit.h"
#include "asm_smp.h"
#include "apic.h"
#include "vesa.h"
#include "syscalls.h"

void run_smp();

// set cpu private value
void smp_set(uint32_t offset, uint32_t value)
{
    uint32_t *cpu_mem=VMEM_CPU_PRIVATE; 
    cpu_mem[offset]=value;
}

// get cpu private value
uint32_t smp_get(uint32_t offset)
{
    uint32_t *cpu_mem=VMEM_CPU_PRIVATE; 
    return cpu_mem[offset];
}

void smp_main_generic(bool bsp)
{
    if(!bsp) // for the bsp this was already done beforehand
    {
	klog("Install Interrupt Vector Table (IVT) on CPU with lapic_id=0x%x ...",apic_id());
	interrupts_install();

	klog("Install Global Descriptor Table (GDT) on CPU with lapic_id=0x%x ...",apic_id());
	gdt_init();

	klog("Setup Paging on CPU with lapic_id=0x%x ...",apic_id());
	struct pdirectory_struct *dir=vmem_kernel_dir();
	x86_set_page_directory(dir);
	x86_paging_enable();
    }

    // setup stack and jump to kernel_ap();
    uint32_t ebp=VMEM_CPU_STACK_TOP;
    asm volatile("mov %0, %%ebp"::"r"(ebp));
    asm volatile("mov %ebp, %esp");
    asm volatile("jmp run_smp");
}

void smp_main()
{
    smp_main_generic(false);
}

void run_smp()
{
    apic_enable();
    
    klog("Setup the LAPIC Timer on CPU with lapic_id=0x%x ...",apic_id());
    apic_init_timer(1);// freq x HZ

    klog("Enable Interrupts on CPU with lapic_id=0x%x ...",apic_id());
    asm_smp_unlock();

    smp_set(SMP_APIC_ID,apic_id());
    smp_set(1000,'a'+apic_id());
    smp_set(SMP_SCHEDULER_INIT,1);

    x86_sti();

    while(1)asm("hlt"); // wait for scheduler to kick in
}

// this will start all our application processors!
void smp_start_aps(acpi_information *pros)
{
    /*
        for(int i=0;i<pros->processors;i++)
	{
	    if(pros->boot==i)continue; // skib bsp

	    uint8_t dest=pros->local_apic_id[i];
	    klog("starting cpu %d (destination apic id: 0x%x) ",i,dest);
	    apic_sipi(dest,0x7); // start on 0x7000
	}
*/	
	smp_main_generic(true);
}