Initial download from archive

http://web.archive.org/web/20210423124630/https://github.com/jdah/tetris-os/blob/master/README.md

src/fpu.c

@@ -0,0 +1,15 @@
+#include "fpu.h"
+
+void fpu_init() {
+    size_t t;
+
+    asm("clts");
+    asm("mov %%cr0, %0" : "=r"(t));
+    t &= ~(1 << 2);
+    t |= (1 << 1);
+    asm("mov %0, %%cr0" :: "r"(t));
+    asm("mov %%cr4, %0" : "=r"(t));
+    t |= 3 << 9;
+    asm("mov %0, %%cr4" :: "r"(t));
+    asm("fninit");
+}