[TOOLCHAIN] Building cross compiler, debugger and bootloader

README.md

@@ -2,3 +2,20 @@ MITTOS64
 ========
 
 By Thomas Lovén - 2016
+
+For development, start by sourcing `activate.sh`
+
+    source ./activate.sh
+
+Running `make` will automatically download and compile a cross compiler
+toolchain and the grub bootloader.
+
+It will also download and build objconv, which is required for building grub
+under OSX. This will probably fail if you're not on a mac.
+
+Building the cross compiler requires a c compiler as well as gmp, mpfr and mpc.
+The c compiler installed by xcode command line tools will do. It's installed
+automatically if you install homebrew. The rest of the packages can be
+installed with homebrew. You'll also want homebrews ctags.
+
+    homebrew install gmp mpfr libmpc ctags