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Enable the PIC and add a timer.

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This causes a GP fault after the timer runs for some time.
This commit is contained in:
Drew Galbraith 2023-05-29 21:52:01 -07:00
parent 80d2bf1aaa
commit 629dca278b
6 changed files with 76 additions and 0 deletions
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25
zion/interrupt/interrupt.cpp
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@ -2,6 +2,7 @@
#include <stdint.h>
#include "common/port.h"
#include "debug/debug.h"
#define IDT_INTERRUPT_GATE 0x8E
@ -95,13 +96,37 @@ extern "C" void interrupt_page_fault(InterruptFrame* frame) {
panic("PF");
}
#define PIC1_COMMAND 0x20
#define PIC1_DATA 0x21
#define PIC_EOI 0x20
uint64_t cnt = 0;
extern "C" void isr_timer();
extern "C" void interrupt_timer(InterruptFrame*) {
cnt++;
if (cnt % 1000 == 0) {
dbgln("timer: %u", cnt);
}
outb(PIC1_COMMAND, PIC_EOI);
}
void EnablePic() {
outb(PIC1_COMMAND, 0x11);
outb(PIC1_DATA, 0x20); // PIC1 offset.
outb(PIC1_DATA, 0x4);
outb(PIC1_DATA, 0x1);
}
void InitIdt() {
gIdt[0] = CreateDescriptor(isr_divide_by_zero);
gIdt[13] = CreateDescriptor(isr_protection_fault);
gIdt[14] = CreateDescriptor(isr_page_fault);
gIdt[32] = CreateDescriptor(isr_timer);
InterruptDescriptorTablePointer idtp{
.size = sizeof(gIdt),
.base = reinterpret_cast<uint64_t>(gIdt),
};
asm volatile("lidt %0" ::"m"(idtp));
EnablePic();
}