First commit, Vystem v0.1

docs/shelter/cpu/asmint.md

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+# ASM instructions
+
+## Introduction
+
+While the Shelter kernel is made in C, somes basic CPU functions require using ASM instructions. For that, we define wrappers that can be used anywhere in the kernel. These wrappers are defined inside the header file `shelter/lib/include/cpu/asm.h` which act as the only place in the entire kernel where the `__asm__` should be used. The subsystem prefix is `sh_asm_`.
+
+## Overview
+
+Here is a list of all the wrappers available. They are all defined as `static inline` function:
+- `inb`: take a `sh_uint16` in input for specifying the port and return the inputed byte
+- `outb`: take a `sh_uint16` for specifying the port and a `sh_uint8` for specifying the byte to output
+- `rdtsc`: take no arguments and return the current TSC as a `sh_uint64`
+- `invlpg`: take a `void *` as an address and return nothing