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/*
* This file is part of the coreboot project.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <console/console.h>
#include <uart.h>
#if CONFIG_USE_OPTION_TABLE
#include <pc80/mc146818rtc.h>
#include "option_table.h"
#endif
unsigned int default_baudrate(void)
{
#if !defined(__SMM__) && CONFIG_USE_OPTION_TABLE
static const unsigned baud[8] =
{ 115200, 57600, 38400, 19200, 9600, 4800, 2400, 1200 };
unsigned b_index = 0;
#if defined(__PRE_RAM__)
b_index = read_option(baud_rate, 0xff);
#else
if (get_option(&b_index, "baud_rate") != CB_SUCCESS)
b_index = 0xff;
#endif
if (b_index < 8)
return baud[b_index];
#endif
return CONFIG_TTYS0_BAUD;
}
/* Calculate divisor. Do not floor but round to nearest integer. */
unsigned int uart_baudrate_divisor(unsigned int baudrate,
unsigned int refclk, unsigned int oversample)
{
return (1 + (2 * refclk) / (baudrate * oversample)) / 2;
}
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