soc/intel/cannonlake: Support Comet Lake v1 and v2 in one build

Define SOC_INTEL_COMETLAKE_1_2, which creates a build supporting both
Comet Lake v1 and v2 by including both sets of FSP binaries and
selecting one based on the CPUID.

A mainboard can select this instead of SOC_INTEL_COMETLAKE_1 or ..._2
to support all CML-U steppings in one build.

Change-Id: Ic8bf444560fd6b57064c47faf038643fabde010e
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/78345
Reviewed-by: Eric Lai <ericllai@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-by: Paul Menzel <paulepanter@mailbox.org>
Reviewed-by: Michał Kopeć <michal.kopec@3mdeb.com>
diff --git a/src/soc/intel/cannonlake/Kconfig b/src/soc/intel/cannonlake/Kconfig
index a42a3c3..fbee465 100644
--- a/src/soc/intel/cannonlake/Kconfig
+++ b/src/soc/intel/cannonlake/Kconfig
@@ -102,6 +102,17 @@
 	bool
 	select SOC_INTEL_COMETLAKE
 
+config SOC_INTEL_COMETLAKE_1_2
+	bool
+	select SOC_INTEL_COMETLAKE
+	select PLATFORM_USES_SECOND_FSP
+	help
+	  Support both CML v1 and v2, for boards that may have either stepping.
+	  Embeds both FSPs and selects the correct one at runtime.  The second
+	  FSP consumes about 800 KiB of flash space.
+
+	  The first FSP is for CML v1, the second is for CML v2.
+
 config SOC_INTEL_COMETLAKE_S
 	bool
 	select SOC_INTEL_COMETLAKE
@@ -285,17 +296,22 @@
 config FSP_HEADER_PATH
 	default "3rdparty/fsp/CoffeeLakeFspBinPkg/Include/" if SOC_INTEL_COFFEELAKE || SOC_INTEL_WHISKEYLAKE
 	default "3rdparty/fsp/CometLakeFspBinPkg/CometLake1/Include/" if SOC_INTEL_COMETLAKE_1
-	default "3rdparty/fsp/CometLakeFspBinPkg/CometLake2/Include/" if SOC_INTEL_COMETLAKE_2
+	# CML v1/v2 headers are equivalent (differ only in comments) so build
+	# against v2 arbitrarily.
+	default "3rdparty/fsp/CometLakeFspBinPkg/CometLake2/Include/" if SOC_INTEL_COMETLAKE_2 || SOC_INTEL_COMETLAKE_1_2
 	default "3rdparty/fsp/CometLakeFspBinPkg/CometLakeS/Include/" if SOC_INTEL_COMETLAKE_S
 	default "3rdparty/fsp/CometLakeFspBinPkg/CometLakeV/Include/" if SOC_INTEL_COMETLAKE_V
 
 config FSP_FD_PATH
 	default "3rdparty/fsp/CoffeeLakeFspBinPkg/Fsp.fd" if SOC_INTEL_COFFEELAKE || SOC_INTEL_WHISKEYLAKE
-	default "3rdparty/fsp/CometLakeFspBinPkg/CometLake1/Fsp.fd" if SOC_INTEL_COMETLAKE_1
+	default "3rdparty/fsp/CometLakeFspBinPkg/CometLake1/Fsp.fd" if SOC_INTEL_COMETLAKE_1 || SOC_INTEL_COMETLAKE_1_2
 	default "3rdparty/fsp/CometLakeFspBinPkg/CometLake2/Fsp.fd" if SOC_INTEL_COMETLAKE_2
 	default "3rdparty/fsp/CometLakeFspBinPkg/CometLakeS/Fsp.fd" if SOC_INTEL_COMETLAKE_S
 	default "3rdparty/fsp/CometLakeFspBinPkg/CometLakeV/Fsp.fd" if SOC_INTEL_COMETLAKE_V
 
+config FSP_FD_PATH_2
+	default "3rdparty/fsp/CometLakeFspBinPkg/CometLake2/Fsp.fd" if SOC_INTEL_COMETLAKE_1_2
+
 config SOC_INTEL_CANNONLAKE_DEBUG_CONSENT
 	int "Debug Consent for CNL"
 	# USB DBC is more common for developers so make this default to 3 if