helos1/driver/irq/pic/pic_init.c

113 lines
3.7 KiB
C

#include "pic.h"
#include "internal.h"
#include "../../../runtime/panic_assert.h"
#include "../../../interrupt/interrupt.h"
#include "../../../runtime/stdio.h"
#include <string.h>
irq_pic_IRQHandlerType irq_pic_IRQHandler[16];
uintptr_t irq_pic_IRQHandler_Data[16];
void * irq_pic_IRQHandlerRaw[16];
bool irq_pic_Enabled;
void irq_pic_Init() {
assert(interrupt_Enabled && "Interrupt must be set up before PIC init");
INTERRUPT_DISABLE;
outb_wait(PIC1_DATA, 0xff); // mask all IRQs
outb_wait(PIC2_DATA, 0xff);
outb_wait(PIC1_COMMAND, ICW1_INIT | ICW1_ICW4);
outb_wait(PIC1_DATA, IRQ_PIC_INT_OFFSET_MASTER); // ICW2: Master PIC interrupt vector offset
outb_wait(PIC1_DATA, 4); // ICW3: tell Master PIC that there is a slave PIC at IRQ2
outb_wait(PIC1_DATA, ICW4_8086);
outb_wait(PIC2_COMMAND, ICW1_INIT | ICW1_ICW4);
outb_wait(PIC2_DATA, IRQ_PIC_INT_OFFSET_SLAVE); // ICW2: Slave PIC interrupt vector offset
outb_wait(PIC2_DATA, 2); // ICW3: tell Slave PIC its cascade identity
outb_wait(PIC2_DATA, ICW4_8086);
outb_wait(PIC1_DATA, 0xfb); // mask all IRQs except IRQ2 (for slave)
outb_wait(PIC2_DATA, 0xff);
memset(irq_pic_IRQHandler, 0, sizeof(irq_pic_IRQHandler)); // reset all IRQ handlers
memset(irq_pic_IRQHandlerRaw, 0, sizeof(irq_pic_IRQHandlerRaw));
// map the IRQ handlers
interrupt_MapHandler(irq_pic_IntHandler20h, 0x20);
interrupt_MapHandler(irq_pic_IntHandler21h, 0x21);
interrupt_MapHandler(irq_pic_IntHandler22h, 0x22);
interrupt_MapHandler(irq_pic_IntHandler23h, 0x23);
interrupt_MapHandler(irq_pic_IntHandler24h, 0x24);
interrupt_MapHandler(irq_pic_IntHandler25h, 0x25);
interrupt_MapHandler(irq_pic_IntHandler26h, 0x26);
interrupt_MapHandler(irq_pic_IntHandler27h, 0x27);
interrupt_MapHandler(irq_pic_IntHandler28h, 0x28);
interrupt_MapHandler(irq_pic_IntHandler29h, 0x29);
interrupt_MapHandler(irq_pic_IntHandler2ah, 0x2a);
interrupt_MapHandler(irq_pic_IntHandler2bh, 0x2b);
interrupt_MapHandler(irq_pic_IntHandler2ch, 0x2c);
interrupt_MapHandler(irq_pic_IntHandler2dh, 0x2d);
interrupt_MapHandler(irq_pic_IntHandler2eh, 0x2e);
interrupt_MapHandler(irq_pic_IntHandler2fh, 0x2f);
irq_pic_Enabled = true;
INTERRUPT_RESTORE;
}
void irq_pic_InitRemap(int offset_master, int offset_slave) {
uint8_t a1, a2; // existing PIC masks
a1 = inb(PIC1_DATA);
a2 = inb(PIC2_DATA);
outb_wait(PIC1_COMMAND, ICW1_INIT | ICW1_ICW4);
outb_wait(PIC2_COMMAND, ICW1_INIT | ICW1_ICW4);
outb_wait(PIC1_DATA, offset_master); // ICW2: Master PIC interrupt vector offset
outb_wait(PIC2_DATA, offset_slave); // ICW2: Slave PIC interrupt vector offset
outb_wait(PIC1_DATA, 4); // ICW3: tell Master PIC that there is a slave PIC at IRQ2 (0000 0100)
outb_wait(PIC2_DATA, 2); // ICW3: tell Slave PIC its cascade identity (0000 0010)
outb_wait(PIC1_DATA, ICW4_8086);
outb_wait(PIC2_DATA, ICW4_8086);
outb_wait(PIC1_DATA, a1); // restore saved masks
outb_wait(PIC2_DATA, a1);
}
void irq_pic_Mask(uint8_t irq_line, bool masked) {
uint16_t port;
if (irq_line < 8)
port = PIC1_DATA;
else {
port = PIC2_DATA;
irq_line -= 8;
}
if (masked)
outb(port, inb(port) | (1 << irq_line));
else
outb(port, inb(port) & ~(1 << irq_line));
}
static inline uint16_t __irq_pic_GetRegister(uint8_t ocw3) {
/* OCW3 to PIC CMD to get the register values. PIC2 is chained, and
* represents IRQs 8-15. PIC1 is IRQs 0-7, with 2 being the chain */
outb_wait(PIC1_COMMAND, ocw3);
outb_wait(PIC2_COMMAND, ocw3);
return ((uint16_t)inb(PIC2_COMMAND) << 8) | inb(PIC1_COMMAND);
}
uint16_t irq_pic_GetIRR() {
return __irq_pic_GetRegister(0x0a); // OCW3 Command: Read IRR
}
uint16_t irq_pic_GetISR() {
return __irq_pic_GetRegister(0x0b); // OCW3 Command: Read ISR
}