Use 115200 bps by default for serial communication

9600 was a standard baud rate decades ago, but 115200 is now more common
so choose defaults that are useful to the largest number of users.

Note that boot0sio does not support rates above 9600 so it remains
unchanged.

Reviewed by:	bz, imp, manu
Relnotes:	Yes
Sponsored by:	The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D36295

1 files changed, 12 insertions, 0 deletions

diff --git a/UPDATING b/UPDATING
index c05670e14f7c..705ca6431a32 100644
--- a/UPDATING
+++ b/UPDATING
@@ -27,6 +27,18 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 14.x IS SLOW:
 	world, or to merely disable the most expensive debugging functionality
 	at runtime, run "ln -s 'abort:false,junk:false' /etc/malloc.conf".)
 
+20230817:
+	Serial communication (in boot loaders, kernel, and userland) has
+	been changed to default to 115200 bps, in line with common industry
+	practice and typcial firmware serial console redirection
+	configuration.
+
+	Note that the early x86 BIOS bootloader (i.e., boot0sio) does not
+	support rates above 9600 bps and is not chagned.  boot0sio users may
+	set BOOT_COMCONSOLE_SPEED=9600 to use 9600 for all of the boot
+	components, or use the standard boot0 and have the boot2 stage start
+	with the serial port at 115200.
+
 20230807:
 	Following the general removal of MIPS support, the ath(4) AHB bus-
 	frontend has been removed, too, and building of the PCI support is