Kyösti Mälkki | 3ee1668 | 2014-02-17 19:37:52 +0200 | [diff] [blame^] | 1 | /* |
| 2 | * This file is part of the coreboot project. |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License as published by |
| 6 | * the Free Software Foundation; version 2 of the License. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 11 | * GNU General Public License for more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU General Public License |
| 14 | * along with this program; if not, write to the Free Software |
| 15 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 16 | */ |
| 17 | |
| 18 | #include <console/console.h> |
| 19 | #include <uart.h> |
| 20 | #if CONFIG_USE_OPTION_TABLE |
| 21 | #include <pc80/mc146818rtc.h> |
| 22 | #include "option_table.h" |
| 23 | #endif |
| 24 | |
| 25 | unsigned int default_baudrate(void) |
| 26 | { |
| 27 | #if !defined(__SMM__) && CONFIG_USE_OPTION_TABLE |
| 28 | static const unsigned baud[8] = |
| 29 | { 115200, 57600, 38400, 19200, 9600, 4800, 2400, 1200 }; |
| 30 | unsigned b_index = 0; |
| 31 | #if defined(__PRE_RAM__) |
| 32 | b_index = read_option(baud_rate, 0xff); |
| 33 | #else |
| 34 | if (get_option(&b_index, "baud_rate") != CB_SUCCESS) |
| 35 | b_index = 0xff; |
| 36 | #endif |
| 37 | if (b_index < 8) |
| 38 | return baud[b_index]; |
| 39 | #endif |
| 40 | return CONFIG_TTYS0_BAUD; |
| 41 | } |
| 42 | |
| 43 | /* Calculate divisor. Do not floor but round to nearest integer. */ |
| 44 | unsigned int uart_baudrate_divisor(unsigned int baudrate, |
| 45 | unsigned int refclk, unsigned int oversample) |
| 46 | { |
| 47 | return (1 + (2 * refclk) / (baudrate * oversample)) / 2; |
| 48 | } |