/* -*- Mode: C; c-basic-offset: 3 -*-
 *
 * timer.c - Interfaces for the various timers available on PC hardware.
 *
 * This file is part of Metalkit, a simple collection of modules for
 * writing software that runs on the bare metal. Get the latest code
 * at http://svn.navi.cx/misc/trunk/metalkit/
 *
 * Copyright (c) 2008-2009 Micah Dowty
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use,
 * copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following
 * conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#include "timer.h"
#include "io.h"

/*
 * Timer_InitPIT --
 *
 *    Set up PIT channel 0 in rate timer mode, with the provided
 *    divisor. It will trigger IRQ 0 at (PIT_HZ / divisor) Hz.
 */

fastcall void
Timer_InitPIT(uint16 divisor)
{
   IO_Out8(0x43, 0x34);
   IO_Out8(0x40, divisor & 0xFF);
   IO_Out8(0x40, divisor >> 8);
}