commit d50d7269ebcb438afa346cdffce0f4e2a1b9e831
author Rob Herring <robh@kernel.org> Fri Apr 18 17:19:58 2014 -0500
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> Thu Apr 24 16:32:27 2014 -0700
tree 7095e7a34467771f9b0e3c2f113cbeb6e7ff5145
parent 0d3c673e7881e691991b2a4745bd4f149603baa2

tty/serial: add arm/arm64 semihosting earlycon

Add earlycon support for the arm/arm64 semihosting debug serial
interface. This allows enabling a debug console when early_params are
processed. This is based on the arm64 earlyprintk smh support and is
intended to replace it.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/kernel-parameters.txt

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 2609ead..4946d8e 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -899,6 +899,8 @@
 			must already be setup and configured. Options are not
 			yet supported.
 
+		smh	Use ARM semihosting calls for early console.
+
 	earlyprintk=	[X86,SH,BLACKFIN,ARM]
 			earlyprintk=vga
 			earlyprintk=efi