[U-Boot] [PATCH 19/39] x86: Build a .rom file which can be flashed to an x86 machine

[Simon Glass]

On x86 machines U-Boot needs to be added to a large ROM image which is
then flashed onto the target board. The ROM has a particular format so it
makes sense for U-Boot to build this image automatically. Unfortunately
it relies on binary blobs so we cannot require this for the default
build as yet.

Create a u-boot.rom output file for this purpose.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

 Makefile                          | 27 ++++++++++++++++++++++++++-
 arch/x86/Kconfig                  |  4 ++++
 include/configs/chromebook_link.h |  2 ++
 3 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index 9c8a580..86d0510 100644
--- a/Makefile
+++ b/Makefile
@@ -743,6 +743,9 @@ ALL-$(CONFIG_SPL) += $(CONFIG_SPL_TARGET:"%"=%)
 endif
 ALL-$(CONFIG_REMAKE_ELF) += u-boot.elf
 
+# We can't do this yet due to the need for binary blobs
+# ALL-$(CONFIG_X86_RESET_VECTOR) += u-boot.rom
+
 # enable combined SPL/u-boot/dtb rules for tegra
 ifneq ($(CONFIG_TEGRA),)
 ifeq ($(CONFIG_SPL),y)
@@ -804,7 +807,8 @@ OBJCOPYFLAGS_u-boot.srec := -O srec
 u-boot.hex u-boot.srec: u-boot FORCE
 	$(call if_changed,objcopy)
 
-OBJCOPYFLAGS_u-boot.bin := -O binary
+OBJCOPYFLAGS_u-boot.bin := -O binary \
+		$(if $(CONFIG_X86_RESET_VECTOR),-R .start16 -R .resetvec)
 
 binary_size_check: u-boot.bin FORCE
 	@file_size=$(shell wc -c u-boot.bin | awk '{print $$1}') ; \
@@ -943,6 +947,27 @@ u-boot-nand.gph: u-boot.bin FORCE
 	$(call if_changed,mkimage)
 	@dd if=/dev/zero bs=8 count=1 2>/dev/null >> $@
 
+# x86 uses a large ROM. We fill it with 0xff, put the 16-bit stuff (including
+# reset vector) at the top, Intel ME at the bottom, and U-Boot in the middle.
+ifneq ($(CONFIG_X86_RESET_VECTOR),)
+rom: u-boot.rom FORCE
+
+u-boot.rom: u-boot-x86-16bit.bin u-boot-dtb.bin \
+		$(srctree)/board/$(BOARDDIR)/descriptor.bin
+	$(objtree)/tools/ifdtool -c -r $(CONFIG_ROM_SIZE) \
+		-D $(srctree)/board/$(BOARDDIR)/descriptor.bin u-boot.tmp
+	$(objtree)/tools/ifdtool -w \
+		$(CONFIG_SYS_TEXT_BASE):$(objtree)/u-boot-dtb.bin u-boot.tmp
+	$(objtree)/tools/ifdtool -w \
+		$(CONFIG_SYS_X86_START16):$(objtree)/u-boot-x86-16bit.bin \
+		u-boot.tmp
+	mv u-boot.tmp $@
+
+OBJCOPYFLAGS_u-boot-x86-16bit.bin := -O binary -j .start16 -j .resetvec
+u-boot-x86-16bit.bin: u-boot FORCE
+	$(call if_changed,objcopy)
+endif
+
 ifneq ($(CONFIG_SUNXI),)
 OBJCOPYFLAGS_u-boot-sunxi-with-spl.bin = -I binary -O binary \
 				   --pad-to=$(CONFIG_SPL_PAD_TO) --gap-fill=0xff
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 07ff149..d9ce129 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -34,6 +34,10 @@ config TARGET_CHROMEBOOK_LINK
 
 endchoice
 
+config ROM_SIZE
+	hex
+	default 0x800000
+
 source "arch/x86/cpu/ivybridge/Kconfig"
 
 source "board/chromebook-x86/coreboot/Kconfig"
diff --git a/include/configs/chromebook_link.h b/include/configs/chromebook_link.h
index 1d6f55b..5e8a747 100644
--- a/include/configs/chromebook_link.h
+++ b/include/configs/chromebook_link.h
@@ -18,8 +18,10 @@
 #define CONFIG_SYS_CAR_ADDR			0xff7e0000
 #define CONFIG_SYS_CAR_SIZE			(128 * 1024)
 #define CONFIG_SYS_MONITOR_LEN			(1 << 20)
+#define CONFIG_SYS_X86_START16			0xfffff800
 #define CONFIG_BOARD_EARLY_INIT_R
 
+#define CONFIG_X86_RESET_VECTOR
 #define CONFIG_NR_DRAM_BANKS			8
 
 /*
-- 
2.1.0.rc2.206.gedb03e5