14 files changed, 126 insertions, 0 deletions

diff --git a/src/mainboard/example/Kconfig b/src/mainboard/example/Kconfig
new file mode 100644
index 0000000000..5afc8ee5a9
--- /dev/null
+++ b/src/mainboard/example/Kconfig
@@ -0,0 +1,15 @@
+if VENDOR_EXAMPLE
+
+choice
+	prompt "Mainboard model"
+
+source "src/mainboard/example/*/Kconfig.name"
+
+endchoice
+
+source "src/mainboard/example/*/Kconfig"
+
+config MAINBOARD_VENDOR
+	default "Example"
+
+endif # VENDOR_EXAMPLE
diff --git a/src/mainboard/example/Kconfig.name b/src/mainboard/example/Kconfig.name
new file mode 100644
index 0000000000..9ffc1738bc
--- /dev/null
+++ b/src/mainboard/example/Kconfig.name
@@ -0,0 +1,2 @@
+config VENDOR_EXAMPLE
+	bool "Example boards"
diff --git a/src/mainboard/example/min86/Kconfig b/src/mainboard/example/min86/Kconfig
new file mode 100644
index 0000000000..3a962e27f4
--- /dev/null
+++ b/src/mainboard/example/min86/Kconfig
@@ -0,0 +1,14 @@
+if BOARD_EXAMPLE_MIN86
+
+config BOARD_SPECIFIC_OPTIONS
+	def_bool y
+	select SOC_EXAMPLE_MIN86
+	select MISSING_BOARD_RESET
+
+config MAINBOARD_DIR
+	default "example/min86"
+
+config MAINBOARD_PART_NUMBER
+	default "Min86"
+
+endif
diff --git a/src/mainboard/example/min86/Kconfig.name b/src/mainboard/example/min86/Kconfig.name
new file mode 100644
index 0000000000..33131930f5
--- /dev/null
+++ b/src/mainboard/example/min86/Kconfig.name
@@ -0,0 +1,11 @@
+config BOARD_EXAMPLE_MIN86
+	bool "Minimal x86 fake board"
+	help
+	  This example mainboard code along with the example/min86 SoC
+	  should serve as a minimal example how a buildable x86 SoC code
+	  base can look like.
+
+	  This can serve, for instance, as a basis to add new SoCs to
+	  coreboot. Starting with a buildable commit should help with
+	  the review of the actual code, and also avoid any regressions
+	  when common coreboot code changes.
diff --git a/src/mainboard/example/min86/board_info.txt b/src/mainboard/example/min86/board_info.txt
new file mode 100644
index 0000000000..c778859fab
--- /dev/null
+++ b/src/mainboard/example/min86/board_info.txt
@@ -0,0 +1 @@
+Category: misc
diff --git a/src/mainboard/example/min86/devicetree.cb b/src/mainboard/example/min86/devicetree.cb
new file mode 100644
index 0000000000..9af04c091a
--- /dev/null
+++ b/src/mainboard/example/min86/devicetree.cb
@@ -0,0 +1,6 @@
+chip soc/example/min86
+
+	device domain 0 on
+	end
+
+end
diff --git a/src/soc/example/Kconfig b/src/soc/example/Kconfig
new file mode 100644
index 0000000000..5bc004aadb
--- /dev/null
+++ b/src/soc/example/Kconfig
@@ -0,0 +1 @@
+source "src/soc/example/*/Kconfig"
diff --git a/src/soc/example/min86/Kconfig b/src/soc/example/min86/Kconfig
new file mode 100644
index 0000000000..38b23c0dd2
--- /dev/null
+++ b/src/soc/example/min86/Kconfig
@@ -0,0 +1,25 @@
+config SOC_EXAMPLE_MIN86
+	bool
+	help
+	  This example SoC code along with the example/min86 mainboard
+	  should serve as a minimal example how a buildable x86 SoC code
+	  base can look like.
+
+	  This can serve, for instance, as a basis to add new SoCs to
+	  coreboot. Starting with a buildable commit should help with
+	  the review of the actual code, and also avoid any regressions
+	  when common coreboot code changes.
+
+if SOC_EXAMPLE_MIN86
+
+config SOC_SPECIFIC_OPTIONS
+	def_bool y
+	select ARCH_ALL_STAGES_X86_32
+	select NO_MONOTONIC_TIMER
+	select NO_MMCONF_SUPPORT
+	select UNKNOWN_TSC_RATE
+
+config DCACHE_BSP_STACK_SIZE		# required by arch/x86/car.ld
+	default 0x100
+
+endif
diff --git a/src/soc/example/min86/Makefile.inc b/src/soc/example/min86/Makefile.inc
new file mode 100644
index 0000000000..9c1c7f0331
--- /dev/null
+++ b/src/soc/example/min86/Makefile.inc
@@ -0,0 +1,15 @@
+ifeq ($(CONFIG_SOC_EXAMPLE_MIN86),y)
+
+bootblock-y	+= cache_as_ram.S
+bootblock-y	+= ../../../cpu/intel/car/bootblock.c
+
+postcar-y	+= exit_car.S
+
+romstage-y	+= romstage.c
+
+ramstage-y	+= chip.c
+ramstage-y	+= timer.c
+
+subdirs-y	+= ../../../cpu/x86/mtrr
+
+endif
diff --git a/src/soc/example/min86/cache_as_ram.S b/src/soc/example/min86/cache_as_ram.S
new file mode 100644
index 0000000000..a350143834
--- /dev/null
+++ b/src/soc/example/min86/cache_as_ram.S
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+.global bootblock_pre_c_entry
+
+.code32
+bootblock_pre_c_entry:
+	call	bootblock_c_entry_bist
+
+.Lhlt:
+	hlt
+	jmp	.Lhlt
diff --git a/src/soc/example/min86/chip.c b/src/soc/example/min86/chip.c
new file mode 100644
index 0000000000..dd09891e3c
--- /dev/null
+++ b/src/soc/example/min86/chip.c
@@ -0,0 +1,3 @@
+#include <device/device.h>
+
+struct chip_operations soc_example_min86_ops = { NULL };
diff --git a/src/soc/example/min86/exit_car.S b/src/soc/example/min86/exit_car.S
new file mode 100644
index 0000000000..0f1b227c2d
--- /dev/null
+++ b/src/soc/example/min86/exit_car.S
@@ -0,0 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+.global chipset_teardown_car
+
+.code32
+chipset_teardown_car:
+	/* Return to caller. */
+	jmp	*%esp
diff --git a/src/soc/example/min86/romstage.c b/src/soc/example/min86/romstage.c
new file mode 100644
index 0000000000..91074b2012
--- /dev/null
+++ b/src/soc/example/min86/romstage.c
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <arch/cpu.h>
+
+asmlinkage void car_stage_entry(void)
+{
+}
diff --git a/src/soc/example/min86/timer.c b/src/soc/example/min86/timer.c
new file mode 100644
index 0000000000..9054ffd972
--- /dev/null
+++ b/src/soc/example/min86/timer.c
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <delay.h>
+
+void init_timer(void)
+{
+}