6 files changed, 23 insertions, 17 deletions

diff --git a/Documentation/mainboard/emulation/qemu-i440fx.md b/Documentation/mainboard/emulation/qemu-i440fx.md
index 059ad123c5f5..a311fddb093e 100644
--- a/Documentation/mainboard/emulation/qemu-i440fx.md
+++ b/Documentation/mainboard/emulation/qemu-i440fx.md
@@ -15,7 +15,7 @@ processor supports x86_64 instructions (long mode).
 The qemu-i440fx mainboard has been ported to x86_64 and will serve as
 reference platform to enable additional platforms.
 
-To enable the support set the Kconfig option ``CONFIG_CPU_QEMU_X86_64=y``.
+To enable the support set the Kconfig option ``CONFIG_USE_EXP_X86_64_SUPPORT=y``.
 
 ## Installing qemu
 
diff --git a/Documentation/mainboard/emulation/qemu-q35.md b/Documentation/mainboard/emulation/qemu-q35.md
index 00163e89fcc7..cebbc637d63b 100644
--- a/Documentation/mainboard/emulation/qemu-q35.md
+++ b/Documentation/mainboard/emulation/qemu-q35.md
@@ -15,7 +15,7 @@ processor supports x86_64 instructions (long mode).
 The qemu-q35 mainboard has been ported to x86_64 and will serve as
 reference platform to enable additional platforms.
 
-To enable the support set the Kconfig option ``CONFIG_CPU_QEMU_X86_64=y``.
+To enable the support set the Kconfig option ``CONFIG_USE_EXP_X86_64_SUPPORT=y``.
 
 ## Installing qemu
 
diff --git a/configs/config.emulation_qemu_x86_i440fx_x86_64 b/configs/config.emulation_qemu_x86_i440fx_x86_64
index 0ddb3f133929..d31bbf2d61de 100644
--- a/configs/config.emulation_qemu_x86_i440fx_x86_64
+++ b/configs/config.emulation_qemu_x86_i440fx_x86_64
@@ -1 +1 @@
-CONFIG_CPU_QEMU_X86_64=y
+CONFIG_USE_EXP_X86_64_SUPPORT=y
diff --git a/src/arch/x86/Kconfig b/src/arch/x86/Kconfig
index 2a42a1c7c71c..ef07a2a03a75 100644
--- a/src/arch/x86/Kconfig
+++ b/src/arch/x86/Kconfig
@@ -63,6 +63,24 @@ config ARCH_ALL_STAGES_X86
 	bool
 	default y
 
+config HAVE_EXP_X86_64_SUPPORT
+	bool
+	help
+	  Enable experimental support to build and run coreboot in 64-bit mode.
+	  When selecting this option for a new platform, it is highly advisable
+	  to provide a config file for Jenkins to build-test the 64-bit option.
+
+config USE_EXP_X86_64_SUPPORT
+	bool "[EXPERIMENTAL] Run coreboot in long (64-bit) mode"
+	depends on HAVE_EXP_X86_64_SUPPORT
+	select ARCH_ALL_STAGES_X86_64
+	help
+	  When set, most of coreboot runs in long (64-bit) mode instead of the
+	  usual protected flat (32-bit) mode. 64-bit CPUs and OSes can be used
+	  irrespective of whether coreboot runs in 32-bit or 64-bit mode. This
+	  is an experimental option: do not enable unless one wants to test it
+	  and has the means to recover a system when coreboot fails to boot.
+
 config ARCH_X86_64_PGTBL_LOC
 	hex "x86_64 page table location in CBFS"
 	depends on ARCH_BOOTBLOCK_X86_64
diff --git a/src/cpu/intel/model_206ax/Kconfig b/src/cpu/intel/model_206ax/Kconfig
index 67fd701c35b0..c168c9bd0148 100644
--- a/src/cpu/intel/model_206ax/Kconfig
+++ b/src/cpu/intel/model_206ax/Kconfig
@@ -3,16 +3,11 @@ config CPU_INTEL_MODEL_206AX
 
 if CPU_INTEL_MODEL_206AX
 
-config ARCH_EXP_X86_64
-	bool "Experimental 64bit support"
-	depends on USE_NATIVE_RAMINIT
-	default n
-
 config CPU_SPECIFIC_OPTIONS
 	def_bool y
-	select ARCH_ALL_STAGES_X86_64 if ARCH_EXP_X86_64
 	select ARCH_X86
 	select BOOT_DEVICE_SPI_FLASH_NO_EARLY_WRITES
+	select HAVE_EXP_X86_64_SUPPORT if USE_NATIVE_RAMINIT
 	select MMX
 	select SSE2
 	select UDELAY_TSC
diff --git a/src/cpu/qemu-x86/Kconfig b/src/cpu/qemu-x86/Kconfig
index 6d897fe5013f..2f961dca9064 100644
--- a/src/cpu/qemu-x86/Kconfig
+++ b/src/cpu/qemu-x86/Kconfig
@@ -3,6 +3,7 @@
 config CPU_QEMU_X86
 	bool
 	select ARCH_X86
+	select HAVE_EXP_X86_64_SUPPORT
 	select UDELAY_TSC
 	select TSC_MONOTONIC_TIMER
 	select UNKNOWN_TSC_RATE
@@ -49,12 +50,4 @@ config MAX_CPUS
 	default 32 if SMM_TSEG
 	default 4
 
-config CPU_QEMU_X86_64
-	bool "Experimental 64bit support"
-	select ARCH_ALL_STAGES_X86_64
-
-config CPU_QEMU_X86_32
-	bool
-	default n if CPU_QEMU_X86_64
-	default y
 endif