90 lines
1.8 KiB
C

#include <apic.h>
#include <mem.h>
#include <debug.h>
#define IOAPIC_BASE 0xFEC00000
#define IOAPIC_DEST_PHYSICAL 0x0
#define IOAPIC_DEST_LOGICAL 0x8
#define IOAPIC_DELIVERY_FIXED 0x0
#define IOAPIC_DELIVERY_LOWEST 0x1
volatile uint32_t *ioregsel = (void *)P2V(IOAPIC_BASE);
volatile uint32_t *iowin = (void *)P2V(IOAPIC_BASE + 0x10);
uint32_t ioapic_read(uint32_t reg)
{
// Read value from APIC register
*ioregsel = reg;
return *iowin;
}
void ioapic_write(uint32_t reg, uint32_t value)
{
// Read value from APIC register
*ioregsel = reg;
*iowin = value;
}
struct ioapic_redirection
{
union
{
struct
{
uint32_t data[2];
}__attribute__((packed));
struct
{
uint8_t vector;
uint8_t mode;
uint8_t mask;
uint32_t reserved;
uint8_t target;
}__attribute__((packed));
};
};
void ioapic_readv(uint8_t irq, struct ioapic_redirection *v)
{
v->data[0] = ioapic_read(0x10 + 2*irq);
v->data[1] = ioapic_read(0x11 + 2*irq);
}
void ioapic_writev(uint8_t irq, struct ioapic_redirection *v)
{
ioapic_write(0x10 + 2*irq, v->data[0]);
ioapic_write(0x11 + 2*irq, v->data[1]);
}
void ioapic_route(uint8_t irq, uint8_t mode, uint8_t target, uint8_t vector)
{
struct ioapic_redirection v;
ioapic_readv(irq, &v);
v.target = target;
v.vector = vector;
v.mode = mode;
ioapic_writev(irq, &v);
}
void ioapic_mask(uint8_t irq)
{
struct ioapic_redirection v;
ioapic_readv(irq, &v);
v.mask |= 1;
ioapic_writev(irq, &v);
}
void ioapic_unmask(uint8_t irq)
{
struct ioapic_redirection v;
ioapic_readv(irq, &v);
v.mask &= 0xFE;
ioapic_writev(irq, &v);
}
void ioapic_init()
{
vmm_set_page(0, (uintptr_t)P2V(IOAPIC_BASE), IOAPIC_BASE, PAGE_PRESENT | PAGE_WRITE);
for(int i = 0; i < 24; i++)
ioapic_route(i, IOAPIC_DEST_LOGICAL | IOAPIC_DELIVERY_LOWEST, 0xFF, INT_IRQ0+i);
}