Commit 5c3a766e authored by Tony Lindgren's avatar Tony Lindgren Committed by Greg Kroah-Hartman
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Documentation: kernel-parameters: Add DEVNAME:0.0 format for serial ports 



Document the console option for DEVNAME:0.0 style addressing for serial
ports.

Suggested-by: default avatarSebastian Reichel <sre@kernel.org>
Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
Reviewed-by: default avatarDhruva Gole <d-gole@ti.com>
Link: https://lore.kernel.org/r/20240327110021.59793-8-tony@atomide.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent a8b04cfe

Documentation/admin-guide/kernel-parameters.txt

+19 −0
Original line number Diff line number Diff line
@@ -785,6 +785,25 @@ 
			Documentation/networking/netconsole.rst for an

			alternative.



		<DEVNAME>:<n>.<n>[,options]

			Use the specified serial port on the serial core bus.

			The addressing uses DEVNAME of the physical serial port

			device, followed by the serial core controller instance,

			and the serial port instance. The options are the same

			as documented for the ttyS addressing above.



			The mapping of the serial ports to the tty instances

			can be viewed with:



			$ ls -d /sys/bus/serial-base/devices/*:*.*/tty/*

			/sys/bus/serial-base/devices/00:04:0.0/tty/ttyS0



			In the above example, the console can be addressed with

			console=00:04:0.0. Note that a console addressed this

			way will only get added when the related device driver

			is ready. The use of an earlycon parameter in addition to

			the console may be desired for console output early on.



		uart[8250],io,<addr>[,options]

		uart[8250],mmio,<addr>[,options]

		uart[8250],mmio16,<addr>[,options]