xnu-3789.60.24.tar.gz

[apple/xnu.git] / osfmk / console / serial_general.c

/*
 * Copyright (c) 2005-2006 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*
 * @OSF_COPYRIGHT@
 */
/*
 * @APPLE_FREE_COPYRIGHT@
 */

#include <kern/spl.h>
#include <mach/std_types.h>
#include <types.h>
#include <kern/thread.h>
#include <console/serial_protos.h>
#include <libkern/section_keywords.h>

extern void cons_cinput(char ch);		/* The BSD routine that gets characters */

SECURITY_READ_ONLY_LATE(unsigned int) serialmode;				/* Serial mode keyboard and console control */

/*
 *  This routine will start a thread that polls the serial port, listening for
 *  characters that have been typed.
 */

void
serial_keyboard_init(void)
{
	kern_return_t	result;
	thread_t		thread;

	if(!(serialmode & 2)) /* Leave if we do not want a serial console */
		return;

	kprintf("Serial keyboard started\n");
	result = kernel_thread_start_priority((thread_continue_t)serial_keyboard_start, NULL, MAXPRI_KERNEL, &thread);
	if (result != KERN_SUCCESS)
		panic("serial_keyboard_init");

	thread_deallocate(thread);
}

void
serial_keyboard_start(void)
{
	/* Go see if there are any characters pending now */
	serial_keyboard_poll();
	panic("serial_keyboard_start: we can't get back here\n");
}

void
serial_keyboard_poll(void)
{
	int chr;
	uint64_t next;

	while(1) {
		chr = _serial_getc(0, 1, 0, 1);	/* Get a character if there is one */
		if(chr < 0) /* The serial buffer is empty */
			break;
		cons_cinput((char)chr);			/* Buffer up the character */
	}

	clock_interval_to_deadline(16, 1000000, &next);	/* Get time of pop */

	assert_wait_deadline((event_t)serial_keyboard_poll, THREAD_UNINT, next);	/* Show we are "waiting" */
	thread_block((thread_continue_t)serial_keyboard_poll);	/* Wait for it */
	panic("serial_keyboard_poll: Shouldn't never ever get here...\n");
}

boolean_t
console_is_serial(void)
{
	return (cons_ops_index == SERIAL_CONS_OPS);
}

int
switch_to_video_console(void)
{
	int old_cons_ops = cons_ops_index;
	cons_ops_index = VC_CONS_OPS;
	return old_cons_ops;
}

int
switch_to_serial_console(void)
{
	int old_cons_ops = cons_ops_index;
	cons_ops_index = SERIAL_CONS_OPS;
	return old_cons_ops;
}

/* The switch_to_{video,serial,kgdb}_console functions return a cookie that
   can be used to restore the console to whatever it was before, in the
   same way that splwhatever() and splx() work.  */
void
switch_to_old_console(int old_console)
{
	static boolean_t squawked;
	uint32_t ops = old_console;

	if ((ops >= nconsops) && !squawked) {
		squawked = TRUE;
		printf("switch_to_old_console: unknown ops %d\n", ops);
	} else
		cons_ops_index = ops;
}