osdev/portio.hpp

#ifndef PORTIO_HPP
#define PORTIO_HPP

#include <cstdint>

inline void outb(std::uint16_t port, std::uint8_t val)
{
    asm volatile("out %%al, %%dx" :: "a"(val), "Nd"(port) : "memory");
}

inline std::uint8_t inb(std::uint16_t port)
{
    std::uint8_t val;
    asm volatile("inb %%dx" : "=a"(val) : "Nd"(port) : "memory");
    return val;
}

inline void outw(std::uint16_t port, std::uint16_t val)
{
    asm volatile("out %%ax, %%dx" :: "a"(val), "Nd"(port) : "memory");
}

inline std::uint16_t inw(std::uint16_t port)
{
    std::uint16_t val;
    asm volatile("inw %%dx" : "=a"(val) : "Nd"(port) : "memory");
    return val;
}

inline void io_wait()
{
    outb(0x80, 0);
}

template<std::uint16_t Addr>
struct Port
{
    Port() = default;

    template<typename T>
    auto operator=(T val) noexcept {
        if constexpr (sizeof(T) == 1)
            outb(Addr, val);
        else if constexpr (sizeof(T) == 2)
            outw(Addr, val);

        return *this;
    }

    template<typename T>
    operator T() const noexcept {
        if constexpr (sizeof(T) == 1)
            return inb(Addr);
        else if constexpr (sizeof(T) == 2)
            return inw(Addr);
    }

    template<typename T>
    bool operator==(T val) const noexcept {
        T dat = *this;
        return dat == val;
    }

    template<typename T>
    auto operator&(T val) const noexcept {
        T dat = *this;
        return dat & val;
    }
};

#endif // PORTIO_HPP