include/apidoc/arch_x86.h File Reference

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Detailed Description

x86(-64) Specific Functions

Author:

John Hodge (thePowersGang)

Table of Contents

• Port IO
• DMA - Direct Memory Access

Port IO

The x86 architecture has two memory spaces, the first is the system memory accessable using standard loads and stores. The second is the 16-bit IO Bus. This bus is accessed using the in and out opcodes and is used to configure devices attached to the system. A driver should not use in and out directly, but instead use the provided in* and out* functions to access the IO Bus. This allows the kernel to run a driver in userspace if requested without the binary needing to be altered.

DMA - Direct Memory Access

Go to the source code of this file.

Functions
IO Bus Access
Uint8	inb (Uint16 Port)
	Read 1 byte from the IO Bus.
Uint16	inw (Uint16 Port)
	Read 2 bytes from the IO Bus.
Uint32	inl (Uint16 Port)
	Read 4 bytes from the IO Bus.
Uint64	inq (Uint16 Port)
	Read 8 bytes from the IO Bus\.
void	outb (Uint16 Port, Uint8 Value)
	Write 1 byte to the IO Bus.
void	outw (Uint16 Port, Uint16 Value)
	Write 2 bytes to the IO Bus.
void	outl (Uint16 Port, Uint32 Value)
	Write 4 bytes to the IO Bus.
void	outq (Uint16 Port, Uint64 Value)
	Write 8 bytes to the IO Bus.