6f77685609
mainly in the kernel and headers. This split based on work by Ingmar Alting <iaalting@cs.vu.nl> done for his Minix PowerPC architecture port. . kernel does not program the interrupt controller directly, do any other architecture-dependent operations, or contain assembly any more, but uses architecture-dependent functions in arch/$(ARCH)/. . architecture-dependent constants and types defined in arch/$(ARCH)/include. . <ibm/portio.h> moved to <minix/portio.h>, as they have become, for now, architecture-independent functions. . int86, sdevio, readbios, and iopenable are now i386-specific kernel calls and live in arch/i386/do_* now. . i386 arch now supports even less 86 code; e.g. mpx86.s and klib86.s have gone, and 'machine.protected' is gone (and always taken to be 1 in i386). If 86 support is to return, it should be a new architecture. . prototypes for the architecture-dependent functions defined in kernel/arch/$(ARCH)/*.c but used in kernel/ are in kernel/proto.h . /etc/make.conf included in makefiles and shell scripts that need to know the building architecture; it defines ARCH=<arch>, currently only i386. . some basic per-architecture build support outside of the kernel (lib) . in clock.c, only dequeue a process if it was ready . fixes for new include files files deleted: . mpx/klib.s - only for choosing between mpx/klib86 and -386 . klib86.s - only for 86 i386-specific files files moved (or arch-dependent stuff moved) to arch/i386/: . mpx386.s (entry point) . klib386.s . sconst.h . exception.c . protect.c . protect.h . i8269.c
65 lines
2.1 KiB
C
Executable file
65 lines
2.1 KiB
C
Executable file
|
|
/* i386-specific clock functions. */
|
|
|
|
#include <ibm/ports.h>
|
|
#include <minix/portio.h>
|
|
|
|
#include "../../kernel.h"
|
|
|
|
#define CLOCK_ACK_BIT 0x80 /* PS/2 clock interrupt acknowledge bit */
|
|
|
|
/* Clock parameters. */
|
|
#define COUNTER_FREQ (2*TIMER_FREQ) /* counter frequency using square wave */
|
|
#define LATCH_COUNT 0x00 /* cc00xxxx, c = channel, x = any */
|
|
#define SQUARE_WAVE 0x36 /* ccaammmb, a = access, m = mode, b = BCD */
|
|
/* 11x11, 11 = LSB then MSB, x11 = sq wave */
|
|
#define TIMER_FREQ 1193182 /* clock frequency for timer in PC and AT */
|
|
#define TIMER_COUNT (TIMER_FREQ/HZ) /* initial value for counter*/
|
|
|
|
/*===========================================================================*
|
|
* arch_init_clock *
|
|
*===========================================================================*/
|
|
PUBLIC int arch_init_clock(void)
|
|
{
|
|
/* Initialize channel 0 of the 8253A timer to, e.g., 60 Hz,
|
|
* and register the CLOCK task's interrupt handler to be run
|
|
* on every clock tick.
|
|
*/
|
|
outb(TIMER_MODE, SQUARE_WAVE); /* run continuously */
|
|
outb(TIMER0, (TIMER_COUNT & 0xff)); /* timer low byte */
|
|
outb(TIMER0, TIMER_COUNT >> 8); /* timer high byte */
|
|
|
|
return OK;
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* clock_stop *
|
|
*===========================================================================*/
|
|
PUBLIC void clock_stop(void)
|
|
{
|
|
/* Reset the clock to the BIOS rate. (For rebooting.) */
|
|
outb(TIMER_MODE, 0x36);
|
|
outb(TIMER0, 0);
|
|
outb(TIMER0, 0);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* read_clock *
|
|
*===========================================================================*/
|
|
PUBLIC clock_t read_clock(void)
|
|
{
|
|
/* Read the counter of channel 0 of the 8253A timer. This counter
|
|
* counts down at a rate of TIMER_FREQ and restarts at
|
|
* TIMER_COUNT-1 when it reaches zero. A hardware interrupt
|
|
* (clock tick) occurs when the counter gets to zero and restarts
|
|
* its cycle.
|
|
*/
|
|
u32_t count;
|
|
|
|
outb(TIMER_MODE, LATCH_COUNT);
|
|
count = inb(TIMER0);
|
|
count |= (inb(TIMER0) << 8);
|
|
|
|
return count;
|
|
}
|
|
|