Add EM100 'hyper term' spi console support in ramstage & smm

The EM100Pro allows the debug console to be sent over the SPI bus.
This is not yet working in romstage due to the use of static variables
in the SPI driver code.  It is also not working on chipsets that have
SPI write buffers of less than 10 characters due to the 9 byte
command/header length specified by the EM100 protocol.

While this currently works only with the EM100, it seems like it would
be useful on any logic analyzer with SPI debug - just filter on command
bytes of 0x11.

Change-Id: Icd42ccd96cab0a10a4e70f4b02ecf9de8169564b
Signed-off-by: Martin Roth <>
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <>
diff --git a/src/Kconfig b/src/Kconfig
index 902855e..bab05f2 100644
--- a/src/Kconfig
+++ b/src/Kconfig
@@ -777,6 +777,7 @@
 	bool "Output verbose SMI debug messages"
 	default n
 	depends on HAVE_SMI_HANDLER
 	  This option enables additional SMI related debug messages.