The defaults and maximum described here are not right. E.g. the default
for amba-pl* is 38400, and meson_uart is 115200.
Finding out likely defaults can be done with the following grep
$ grep -R 'int\s*baud\s*=\s*[0-9]\+' drivers/tty/serial/
While not all results will be in the .setup function for the console,
many are.
As for maximums, I couldn't trivially find out if 8250 does have a
maximum defined in the kernel driver, but some platforms do go higher,
e.g. the common baud rate for Rockchip hardware is 1500000.
Signed-off-by: Samuel Dionne-Riel <samuel@xxxxxxxxxxxxxxx>
---
Documentation/admin-guide/kernel-parameters.txt | 2 +-
Documentation/admin-guide/serial-console.rst | 5 +++--
2 files changed, 4 insertions(+), 3 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index cb89dbdedc463..6e0f8a8229bca 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -649,7 +649,7 @@
the form "bbbbpnf", where "bbbb" is the baud rate,
"p" is parity ("n", "o", or "e"), "n" is number of
bits, and "f" is flow control ("r" for RTS or
- omit it). Default is "9600n8".
+ omit it). Default depends on the driver.
See Documentation/admin-guide/serial-console.rst for more
information. See
diff --git a/Documentation/admin-guide/serial-console.rst b/Documentation/admin-guide/serial-console.rst
index 58b32832e50aa..41977dd13ab7e 100644
--- a/Documentation/admin-guide/serial-console.rst
+++ b/Documentation/admin-guide/serial-console.rst
@@ -29,8 +29,9 @@ The format of this option is::
defines the baudrate/parity/bits/flow control of
the port, in the format BBBBPNF, where BBBB is the
speed, P is parity (n/o/e), N is number of bits,
- and F is flow control ('r' for RTS). Default is
- 9600n8. The maximum baudrate is 115200.
+ and F is flow control ('r' for RTS). Default depends
+ on the driver. The maximum baudrate depends on the
+ device.
You can specify multiple console= options on the kernel command line.
Output will appear on all of them. The last device will be used when
--
2.32.0
