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-rw-r--r--src/drivers/uart/Makefile.inc6
-rw-r--r--src/drivers/uart/util.c48
2 files changed, 54 insertions, 0 deletions
diff --git a/src/drivers/uart/Makefile.inc b/src/drivers/uart/Makefile.inc
new file mode 100644
index 0000000000..c797d4b44d
--- /dev/null
+++ b/src/drivers/uart/Makefile.inc
@@ -0,0 +1,6 @@
+ifeq ($(CONFIG_CONSOLE_SERIAL),y)
+romstage-y += util.c
+ramstage-y += util.c
+bootblock-y += util.c
+smm-y += util.c
+endif
diff --git a/src/drivers/uart/util.c b/src/drivers/uart/util.c
new file mode 100644
index 0000000000..c577048fb5
--- /dev/null
+++ b/src/drivers/uart/util.c
@@ -0,0 +1,48 @@
+/*
+ * 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;
+}