diff options
Diffstat (limited to 'src/arch/x86_64/asm/io_port.s')
| -rw-r--r-- | src/arch/x86_64/asm/io_port.s | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/src/arch/x86_64/asm/io_port.s b/src/arch/x86_64/asm/io_port.s index e69de29..9ddc4e6 100644 --- a/src/arch/x86_64/asm/io_port.s +++ b/src/arch/x86_64/asm/io_port.s @@ -0,0 +1,71 @@ +;*************************************************************************** +;* Operating-System Construction * +;*---------------------------------------------------------------------------* +;* * +;* I O _ P O R T * +;* * +;*---------------------------------------------------------------------------* +;* The functions defined here encapsulate the machine instructions 'in' and * +;* 'out' for class IO_Port. * +;***************************************************************************** + +; EXPORTED FUNCTIONS + +[GLOBAL outb] +[GLOBAL outw] +[GLOBAL inb] +[GLOBAL inw] + +; FUNCTION IMPLEMENTATIONS + +[SECTION .text] + +; OUTB: Byte-wise output via an I/O port. +; +; C prototype: void outb (int port, int value); + +outb: + push rbp + mov rbp, rsp + mov rdx, rdi + mov rax, rsi + out dx, al + pop rbp + ret + +; OUTW: Word-wise output via an I/O port. +; +; C prototype: void outw (int port, int value); + +outw: + push rbp + mov rbp, rsp + mov rdx, rdi + mov rax, rsi + out dx, ax + pop rbp + ret + +; INB: Byte-wise input via an I/O port. +; +; C prototype: unsigned char inb (int port); + +inb: + push rbp + mov rbp, rsp + mov rdx, rdi + in al, dx + pop rbp + ret + +; INW: Word-wise input via an I/O port. +; +; C prototype: unsigned short inw (int port); + +inw: + push rbp + mov rbp, rsp + mov rdx, rdi + in ax, dx + pop rbp + ret |