Blackfin arch: Initial patch to add earlyprintk support

This allows debugging of problems which happen eary in the kernel
boot process (after bootargs are parsed, but before serial subsystem
is fully initialized)

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 4d175c7..a57c1f2 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -35,6 +35,7 @@
 	APIC	APIC support is enabled.
 	APM	Advanced Power Management support is enabled.
 	AX25	Appropriate AX.25 support is enabled.
+	BLACKFIN Blackfin architecture is enabled.
 	DRM	Direct Rendering Management support is enabled.
 	EDD	BIOS Enhanced Disk Drive Services (EDD) is enabled
 	EFI	EFI Partitioning (GPT) is enabled
@@ -550,7 +551,7 @@
 
 	dtc3181e=	[HW,SCSI]
 
-	earlyprintk=	[X86-32,X86-64,SH]
+	earlyprintk=	[X86-32,X86-64,SH,BLACKFIN]
 			earlyprintk=vga
 			earlyprintk=serial[,ttySn[,baudrate]]