xref: /openbmc/linux/usr/initramfs_data.S (revision 0545810f)
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3  initramfs_data includes the compressed binary that is the
4  filesystem used for early user space.
5  Note: Older versions of "as" (prior to binutils 2.11.90.0.23
6  released on 2001-07-14) dit not support .incbin.
7  If you are forced to use older binutils than that then the
8  following trick can be applied to create the resulting binary:
9
10
11  ld -m elf_i386  --format binary --oformat elf32-i386 -r \
12  -T initramfs_data.scr initramfs_data.cpio.gz -o initramfs_data.o
13   ld -m elf_i386  -r -o built-in.a initramfs_data.o
14
15  For including the .init.ramfs sections, see include/asm-generic/vmlinux.lds.
16
17  The above example is for i386 - the parameters vary from architectures.
18  Eventually look up LDFLAGS_BLOB in an older version of the
19  arch/$(ARCH)/Makefile to see the flags used before .incbin was introduced.
20
21  Using .incbin has the advantage over ld that the correct flags are set
22  in the ELF header, as required by certain architectures.
23*/
24
25.section .init.ramfs,"a"
26__irf_start:
27.incbin "usr/initramfs_inc_data"
28__irf_end:
29.section .init.ramfs.info,"a"
30.globl __initramfs_size
31__initramfs_size:
32#ifdef CONFIG_64BIT
33	.quad __irf_end - __irf_start
34#else
35	.long __irf_end - __irf_start
36#endif
37