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Diffstat (limited to 'arch/i386/kernel/pic.c')
-rw-r--r--arch/i386/kernel/pic.c67
1 files changed, 67 insertions, 0 deletions
diff --git a/arch/i386/kernel/pic.c b/arch/i386/kernel/pic.c
new file mode 100644
index 0000000..69a0785
--- /dev/null
+++ b/arch/i386/kernel/pic.c
@@ -0,0 +1,67 @@
+#include <kernel/pic.h>
+
+void pic_eoi(unsigned char irq) {
+ if (irq >= 8)
+ outb(PIC2_COMMAND, 0x20);
+ outb(PIC1_COMMAND, 0x20);
+}
+
+void pic_remap(void) {
+ unsigned char a1 = inb(PIC1_DATA);
+ unsigned char a2 = inb(PIC2_DATA);
+
+ outb(PIC1_COMMAND, ICW1_INIT | ICW1_ICW4);
+ outb(PIC2_COMMAND, ICW1_INIT | ICW1_ICW4);
+ outb(PIC1_DATA, PIC1);
+ outb(PIC2_DATA, PIC2);
+ outb(PIC1_DATA, 4);
+ outb(PIC2_DATA, 2);
+ outb(PIC1_DATA, ICW4_8086);
+ outb(PIC2_DATA, ICW4_8086);
+ outb(PIC1_DATA, a1);
+ outb(PIC2_DATA, a2);
+}
+
+static uint16_t __pic_get_irq_reg(int ocw3) {
+ outb(PIC1_COMMAND, ocw3);
+ outb(PIC2_COMMAND, ocw3);
+ return (inb(PIC2_COMMAND) << 8) | inb(PIC1_COMMAND);
+}
+
+uint16_t pic_get_irr(void) {
+ return __pic_get_irq_reg(PIC_READ_IRR);
+}
+
+uint16_t pic_get_isr(void) {
+ return __pic_get_irq_reg(PIC_READ_ISR);
+}
+
+void irq_set_mask(uint8_t irq) {
+ uint16_t port;
+ uint8_t data;
+
+ if (irq < 8) {
+ port = PIC1_DATA;
+ } else {
+ port = PIC2_DATA;
+ irq -= 8;
+ }
+
+ data = inb(port) | (1 << irq);
+ outb(port, data);
+}
+
+void irq_clear_mask(uint8_t irq) {
+ uint16_t port;
+ uint8_t data;
+
+ if (irq < 8) {
+ port = PIC1_DATA;
+ } else {
+ port = PIC2_DATA;
+ irq -= 8;
+ }
+
+ data = inb(port) & ~(1 << irq);
+ outb(port, data);
+}