d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Made the timeouts in gets() machine-independent. Use the BIOS tick

Browse Source 
counter instead of the BIOS time call to save space.

Reworked the anti-noise timeout to avoid duplicating code.  The timeout
in the outer loop is now restarted after every noise timeout, so it is
now possible for the total timeout to be infinite; previously, the maximum
total timeout was 150000 seconds.
This commit is contained in:
bde 1996-03-08 06:11:33 +00:00
parent 501805941c
commit 627e1bd585
1 changed files with 35 additions and 31 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

66
sys/i386/boot/biosboot/io.c
View File

@ -24,7 +24,7 @@
* the rights to redistribute these changes.
*
* from: Mach, Revision 2.2 92/04/04 11:35:57 rpd
* $Id: io.c,v 1.15 1995/06/25 14:02:53 joerg Exp $
* $Id: io.c,v 1.16 1996/01/21 11:30:12 joerg Exp $
*/
#include "boot.h"
@ -161,8 +161,7 @@ loop:
* is not a valid ISA bus address, those machines execute this inb in
* 60 nS :-(.
*
* XXX we need to use BIOS timer calls or something more reliable to
* produce timeouts in the boot code.
* XXX this should be converted to use bios_tick.
*/
void
delay1ms(void)
@ -172,21 +171,34 @@ delay1ms(void)
(void)inb(0x84);
}
static __inline unsigned
pword(unsigned physaddr)
{
unsigned result;
/*
* Give the fs prefix separately because gas omits it for
* "movl %fs:0x46c, %eax".
*/
__asm __volatile("fs; movl %1, %0" : "=r" (result)
: "m" (*(unsigned *)physaddr));
return (result);
}
int
gets(char *buf)
{
int i;
#if TIMEOUT+0 > 0
int j;
#endif
#define bios_tick pword(0x46c)
#define BIOS_TICK_MS 55
unsigned initial_bios_tick;
char *ptr=buf;
#if TIMEOUT+0 == 0
#if BOOTWAIT
for (i = BOOTWAIT; i>0; delay1ms(),i--)
for (initial_bios_tick = bios_tick;
bios_tick - initial_bios_tick < BOOTWAIT / BIOS_TICK_MS;)
#endif
if ((loadflags & RB_SERIAL) ? serial_ischar() : ischar())
for (;;)
for (;;) {
switch(*ptr = getchar(ptr - buf) & 0xff) {
case '\n':
case '\r':
@ -198,28 +210,20 @@ gets(char *buf)
default:
ptr++;
}
#else /* TIMEOUT */
#if BOOTWAIT == 0
# error "TIMEOUT without BOOTWAIT"
#if TIMEOUT + 0
#if !BOOTWAIT
#error "TIMEOUT without BOOTWAIT"
#endif
for (i = BOOTWAIT; i>0; delay1ms(),i--)
if ((loadflags & RB_SERIAL) ? serial_ischar() : ischar())
for (j = TIMEOUT; j>0; delay1ms(),j--)
if ((loadflags & RB_SERIAL) ?
serial_ischar() : ischar())
switch(*ptr = getchar(ptr - buf) &
0xff) {
case '\n':
case '\r':
*ptr = '\0';
return 1;
case '\b':
if (ptr > buf) ptr--;
continue;
default:
ptr++;
}
#endif /* !TIMEOUT */
for (initial_bios_tick = bios_tick;;) {
if ((loadflags & RB_SERIAL) ?
serial_ischar() : ischar())
break;
if (bios_tick - initial_bios_tick >=
TIMEOUT / BIOS_TICK_MS)
return 0;
}
#endif
}
return 0;
}