mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-27 06:15:08 +07:00
97873a3daf
Based on 1 normalized pattern(s): this file is part of the linux kernel and is made available under the terms of the gnu general public license version 2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 28 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.534229504@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
138 lines
2.3 KiB
C
138 lines
2.3 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/* -*- linux-c -*- ------------------------------------------------------- *
|
|
*
|
|
* Copyright (C) 1991, 1992 Linus Torvalds
|
|
* Copyright 2007 rPath, Inc. - All Rights Reserved
|
|
* Copyright 2009 Intel Corporation; author H. Peter Anvin
|
|
*
|
|
* ----------------------------------------------------------------------- */
|
|
|
|
/*
|
|
* Very simple screen and serial I/O
|
|
*/
|
|
|
|
#include "boot.h"
|
|
|
|
int early_serial_base;
|
|
|
|
#define XMTRDY 0x20
|
|
|
|
#define TXR 0 /* Transmit register (WRITE) */
|
|
#define LSR 5 /* Line Status */
|
|
|
|
/*
|
|
* These functions are in .inittext so they can be used to signal
|
|
* error during initialization.
|
|
*/
|
|
|
|
static void __attribute__((section(".inittext"))) serial_putchar(int ch)
|
|
{
|
|
unsigned timeout = 0xffff;
|
|
|
|
while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
|
|
cpu_relax();
|
|
|
|
outb(ch, early_serial_base + TXR);
|
|
}
|
|
|
|
static void __attribute__((section(".inittext"))) bios_putchar(int ch)
|
|
{
|
|
struct biosregs ireg;
|
|
|
|
initregs(&ireg);
|
|
ireg.bx = 0x0007;
|
|
ireg.cx = 0x0001;
|
|
ireg.ah = 0x0e;
|
|
ireg.al = ch;
|
|
intcall(0x10, &ireg, NULL);
|
|
}
|
|
|
|
void __attribute__((section(".inittext"))) putchar(int ch)
|
|
{
|
|
if (ch == '\n')
|
|
putchar('\r'); /* \n -> \r\n */
|
|
|
|
bios_putchar(ch);
|
|
|
|
if (early_serial_base != 0)
|
|
serial_putchar(ch);
|
|
}
|
|
|
|
void __attribute__((section(".inittext"))) puts(const char *str)
|
|
{
|
|
while (*str)
|
|
putchar(*str++);
|
|
}
|
|
|
|
/*
|
|
* Read the CMOS clock through the BIOS, and return the
|
|
* seconds in BCD.
|
|
*/
|
|
|
|
static u8 gettime(void)
|
|
{
|
|
struct biosregs ireg, oreg;
|
|
|
|
initregs(&ireg);
|
|
ireg.ah = 0x02;
|
|
intcall(0x1a, &ireg, &oreg);
|
|
|
|
return oreg.dh;
|
|
}
|
|
|
|
/*
|
|
* Read from the keyboard
|
|
*/
|
|
int getchar(void)
|
|
{
|
|
struct biosregs ireg, oreg;
|
|
|
|
initregs(&ireg);
|
|
/* ireg.ah = 0x00; */
|
|
intcall(0x16, &ireg, &oreg);
|
|
|
|
return oreg.al;
|
|
}
|
|
|
|
static int kbd_pending(void)
|
|
{
|
|
struct biosregs ireg, oreg;
|
|
|
|
initregs(&ireg);
|
|
ireg.ah = 0x01;
|
|
intcall(0x16, &ireg, &oreg);
|
|
|
|
return !(oreg.eflags & X86_EFLAGS_ZF);
|
|
}
|
|
|
|
void kbd_flush(void)
|
|
{
|
|
for (;;) {
|
|
if (!kbd_pending())
|
|
break;
|
|
getchar();
|
|
}
|
|
}
|
|
|
|
int getchar_timeout(void)
|
|
{
|
|
int cnt = 30;
|
|
int t0, t1;
|
|
|
|
t0 = gettime();
|
|
|
|
while (cnt) {
|
|
if (kbd_pending())
|
|
return getchar();
|
|
|
|
t1 = gettime();
|
|
if (t0 != t1) {
|
|
cnt--;
|
|
t0 = t1;
|
|
}
|
|
}
|
|
|
|
return 0; /* Timeout! */
|
|
}
|
|
|