acpi: Provide a way to build in a boot logo

EFI has a Boot Graphics Record Table which can be used to show a logo
when booting up and shutting down.

Add support for adding this to the image, using a U-Boot logo which
includes the name, since many people will be unfamiliar with the logo.

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

lib/acpi/Makefile

@@ -11,6 +11,8 @@ obj-$(CONFIG_$(PHASE_)ACPIGEN) += acpi_dp.o
 obj-$(CONFIG_$(PHASE_)ACPIGEN) += acpi_table.o
 obj-y += acpi_writer.o
 
+obj-y += bgrt_image.o
+
 # With QEMU the ACPI tables come from there, not from U-Boot
 ifndef CONFIG_QFW_ACPI
 obj-y += base.o

scripts/Makefile.lib

@@ -495,6 +495,24 @@ cmd_S_splash=						\
 $(obj)/%_logo.S: $(src)/%_logo.bmp
 	$(call cmd,S_splash)
 
+# Generate an assembly file to wrap the EFI 'Boot Graphics Resource Table' image
+quiet_cmd_S_bgrt= BGRT    $@
+# Modified for U-Boot
+cmd_S_bgrt=						\
+(							\
+	echo '.section .rodata.bgrt.init,"a"';		\
+	echo '.balign 16';				\
+	echo '.global __$(*F)_image_begin';		\
+	echo '__$(*F)_image_begin:';			\
+	echo '.incbin "$<" ';				\
+	echo '__$(*F)_image_end:';			\
+	echo '.global __$(*F)_image_end';			\
+	echo '.balign 16';				\
+) > $@
+
+$(obj)/%_image.S: $(src)/%_image.bmp
+	$(call cmd,S_bgrt)
+
 # EFI applications
 # A Makefile target *.efi is built as EFI application.
 # A Makefile target *_efi.S wraps *.efi as built-in EFI application.