Implemented serial driver

kernel/src/system.c

@@ -0,0 +1,39 @@
+#include <kernel.h>
+
+void cpuid(uint32_t* eax, uint32_t* ebx, uint32_t* ecx, uint32_t* edx) {
+	__asm__ volatile ("cpuid"
+		: "=a"(*eax), "=b"(*ebx), "=c"(*ecx), "=d"(*edx)
+		: "a"(*eax)
+		: "memory");
+}
+
+uint8_t inb(uint16_t port) {
+	uint8_t r;
+	__asm__ volatile ("inb %1, %0" : "=a"(r) : "dN"(port));
+	return r;
+}
+
+void outb(uint16_t port, uint8_t data) {
+	__asm__ volatile ("outb %1, %0" :: "dN"(port), "a"(data));
+}
+
+uint16_t inw(uint16_t port) {
+	uint16_t r;
+	__asm__ volatile ("inw %1, %0" : "=a"(r) : "dN"(port));
+	return r;
+}
+
+void outw(uint16_t port, uint16_t data) {
+	__asm__ volatile ("outw %1, %0" :: "dN"(port), "a"(data));
+}
+
+uint32_t inl(uint16_t port) {
+	uint32_t r;
+	__asm__ volatile ("inl %1, %0" : "=a"(r) : "dN"(port));
+	return r;
+}
+
+void outl(uint16_t port, uint32_t data) {
+	__asm__ volatile ("outl %1, %0" :: "dN"(port), "a"(data));
+}
+