diff options
| -rw-r--r-- | arch/mips/Kconfig | 18 | ||||
| -rw-r--r-- | arch/mips/boot/compressed/head.S | 16 | ||||
| -rw-r--r-- | arch/mips/boot/compressed/ld.script | 6 |
3 files changed, 39 insertions, 1 deletions
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 7cb5f6d..a2ee09c 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -2702,6 +2702,24 @@ choice look like a DTB header after a reboot if no actual DTB is appended to vmlinux.bin. Do not leave this option active in a production kernel if you don't intend to always append a DTB. + + config MIPS_ZBOOT_APPENDED_DTB + bool "vmlinuz.bin" + depends on SYS_SUPPORTS_ZBOOT + help + With this option, the boot code will look for a device tree binary + DTB) appended to raw vmlinuz.bin (with decompressor). + (e.g. cat vmlinuz.bin <filename>.dtb > vmlinuz_w_dtb). + + This is meant as a backward compatibility convenience for those + systems with a bootloader that can't be upgraded to accommodate + the documented boot protocol using a device tree. + + Beware that there is very little in terms of protection against + this option being confused by leftover garbage in memory that might + look like a DTB header after a reboot if no actual DTB is appended + to vmlinuz.bin. Do not leave this option active in a production kernel + if you don't intend to always append a DTB. endchoice endmenu diff --git a/arch/mips/boot/compressed/head.S b/arch/mips/boot/compressed/head.S index 409cb48..c580e85 100644 --- a/arch/mips/boot/compressed/head.S +++ b/arch/mips/boot/compressed/head.S @@ -25,6 +25,22 @@ start: move s2, a2 move s3, a3 +#ifdef CONFIG_MIPS_ZBOOT_APPENDED_DTB + PTR_LA t0, __appended_dtb +#ifdef CONFIG_CPU_BIG_ENDIAN + li t1, 0xd00dfeed +#else + li t1, 0xedfe0dd0 +#endif + lw t2, (t0) + bne t1, t2, not_found + nop + + move s1, t0 + PTR_LI s0, -2 +not_found: +#endif + /* Clear BSS */ PTR_LA a0, _edata PTR_LA a2, _end diff --git a/arch/mips/boot/compressed/ld.script b/arch/mips/boot/compressed/ld.script index 5a33409..2ed08fb 100644 --- a/arch/mips/boot/compressed/ld.script +++ b/arch/mips/boot/compressed/ld.script @@ -29,8 +29,12 @@ SECTIONS *(.image) __image_end = .; CONSTRUCTORS + . = ALIGN(16); } - . = ALIGN(16); + __appended_dtb = .; + /* leave space for appended DTB */ + . += 0x100000; + _edata = .; /* End of data section */ |