Include file restructure!

- include/ now has subdirs - standard C headers will be in 'include/c'. Any program can include these - all other header shall only be used by the kernel
2024-05-07 21:01:50 +02:00
parent 41e0b93f52
commit 7826b9b7d4
20 changed files with 33 additions and 83 deletions
@@ -0,0 +1,95 @@
+#ifndef PIC_H
+#define PIC_H
+
+#include <ports/io.h>
+
+// PIC I/O Ports
+#define PIC_1_CMD  0x20
+#define PIC_1_DATA 0x21
+#define PIC_2_CMD  0xA0
+#define PIC_2_DATA 0xA1
+
+// IRQs
+#define NEW_IRQ_0 0x20 // IRQ 0 : int 32
+#define NEW_IRQ_8 0x28 // IRQ 8 : int 40
+
+// Commands
+#define PIC_EOI 0x20 // End Of Interrupt
+#define PIC_DISABLE 0xff
+
+void sendPicEOI(uint8_t irq) {
+    if (irq >= 8) {
+        outb(PIC_2_CMD, PIC_EOI);
+    }
+    outb(PIC_1_CMD, PIC_EOI);
+}
+
+void disableIrqs() {
+    outb(PIC_2_DATA, PIC_DISABLE);
+    outb(PIC_1_DATA, PIC_DISABLE);
+}
+
+void setIrqMask(uint8_t irq) {
+    uint16_t port;
+    uint8_t value;
+
+    if (irq < 8) {
+        port = PIC_1_DATA;
+    } else {
+        irq -= 8;
+        port = PIC_2_DATA;
+    }
+
+    value = inb(port) | (1 << irq);
+    outb(port, value);
+}
+
+void unsetIrqMask(uint8_t irq) {
+    uint16_t port;
+    uint8_t value;
+
+    if (irq < 8) {
+        port = PIC_1_DATA;
+    } else {
+        irq -= 8;
+        port = PIC_2_DATA;
+    }
+
+    value = inb(port) & ~(1 << irq);
+    outb(port, value);
+}
+
+void remapPic() {
+    uint8_t pic1Mask = inb(PIC_1_DATA);
+    uint8_t pic2Mask = inb(PIC_2_DATA);
+
+    // Send Init Control Word 1-4 to both PICs
+    // ICW 1: bit 0 - send up to 4 ICWs, bit 4 - Init PIC
+    outb(PIC_1_CMD, 0x11);
+    ioWait(); // For slower machines
+    outb(PIC_2_CMD, 0x11);
+    ioWait();
+
+    // ICW 2: Where to map IRW bases in IDT
+    outb(PIC_1_DATA, NEW_IRQ_0);
+    ioWait();
+    outb(PIC_2_DATA, NEW_IRQ_8);
+    ioWait();
+
+    // ICW 3: Which IRQ in PIC1 is PIC2; Mapping PIC2 to IRQ 2
+    outb(PIC_1_DATA, 0x04);
+    ioWait();
+    outb(PIC_2_DATA, 0x02);
+    ioWait();
+
+    // ICW 4 - Set x86 mode
+    outb(PIC_1_DATA, 0x01);
+    ioWait();
+    outb(PIC_2_DATA, 0x01);
+    ioWait();
+
+    outb(PIC_1_DATA, pic1Mask);
+    outb(PIC_2_DATA, pic2Mask);
+}
+
+#endif