Hi Geert,
On 21/2/25 00:06, Geert Uytterhoeven wrote:
Hi Greg,
On Tue, 18 Feb 2025 at 13:54, Greg Ungerer <gerg@xxxxxxxxxxxxxx> wrote:
If there is no capability for the boot loader to specify a devicetree
blob then this option allows for it to be embedded within the linux
kernel binary itself. This change specifically adds this embedding
support for the m68knommu targets.
Signed-off-by: Greg Ungerer <gerg@xxxxxxxxxxxxxx>
Thanks for your patch!
--- a/arch/m68k/Kconfig.devices
+++ b/arch/m68k/Kconfig.devices
@@ -144,3 +144,14 @@ config SERIAL_CONSOLE
endmenu
endif
+
+config EMBEDDED_DTB
BUILTIN_DTB
+ bool "Embedded devicetree ELF section"
select GENERIC_BUILTIN_DTB
+ help
+ If there is no capability for the boot loader to specify a
+ devicetree (DTB) then this option allows for it to be embedbed
+ within the linux binary itself. Typically you can do this with
+ something like this:
+
+ objcopy --update-section .embedded_dtb=<filename>.dtb vmlinux
+
--- a/arch/m68k/kernel/vmlinux-nommu.lds
+++ b/arch/m68k/kernel/vmlinux-nommu.lds
@@ -70,6 +70,15 @@ SECTIONS {
INIT_TEXT_SECTION(PAGE_SIZE)
INIT_DATA_SECTION(16)
PERCPU_SECTION(16)
+
+#ifdef CONFIG_EMBEDDED_DTB
+ STRUCT_ALIGN();
+ .embedded_dtb : {
+ embedded_dtb = .;
+ *(.embedded_dtb)
+ KEEP(*(.embedded_dtb))
+ }
+#endif
.m68k_fixup : {
__start_fixup = .;
*(.m68k_fixup)
Please use the existing DTB support in include/asm-generic/vmlinux.lds.h.
Oh yes, that is much better. Using CONFIG_BUILTIN_DTB_NAME simplifies
it all a lot more too. Will use that in the next version.
Thanks
Greg
