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#include <ioapic.h>
#include <apic.h>
#include <paging.h>
#include <libk/stdio.h>
void ioapic_eoi()
{
*((volatile uint32_t*)((uint64_t)lapic_addr + 0xB0)) = 0;
}
uint32_t ioapic_read(const uint8_t offset)
{
/* tell IOREGSEL where we want to read from */
*(volatile uint32_t*)(uint64_t)ioapic_addr = offset;
/* return the data from IOWIN */
return *(volatile uint32_t*)((uint64_t)ioapic_addr + 0x10);
}
void ioapic_write(const uint8_t offset, const uint32_t val)
{
/* tell IOREGSEL where we want to write to */
*(volatile uint32_t*)(uint64_t)ioapic_addr = offset;
/* write the value to IOWIN */
*(volatile uint32_t*)((uint64_t)ioapic_addr + 0x10) = val;
}
void ioapic_set_irq(uint8_t irq, uint64_t apic_id, uint8_t vector)
{
const uint32_t low_index = (uint32_t)0x10 + irq*2;
const uint32_t high_index = (uint32_t)0x10 + irq*2 + 1;
uint32_t high = ioapic_read((uint8_t)high_index);
// set APIC ID
high &= (uint32_t)~0xff000000;
high |= (uint32_t)apic_id << 24;
ioapic_write((uint8_t)high_index, high);
uint32_t low = ioapic_read((uint8_t)low_index);
// unmask the IRQ
low &= (uint32_t)~(1<<16);
// set to physical delivery mode
low &= (uint32_t)~(1<<11);
// set to fixed delivery mode
low &= (uint32_t)~0x700;
// set delivery vector
low &= (uint32_t)~0xff;
low |= vector;
ioapic_write((uint8_t)low_index, low);
}
void apic_remap_interrupts()
{
uint8_t bspid = curr_cpu_apic_id();
map_addr(ioapic_addr, ioapic_addr, FLAG_PRESENT);
map_addr(lapic_addr, lapic_addr, FLAG_PRESENT);
// irq is 2 because of gsi remap
ioapic_set_irq(0x2, bspid, 0x20); // timer
ioapic_set_irq(0x1, bspid, 0x21); // keyboard
__asm__ volatile ("sti;");
}
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