diff options
| -rw-r--r-- | arch/mips/Kconfig | 27 | ||||
| -rw-r--r-- | arch/mips/kernel/head.S | 16 | ||||
| -rw-r--r-- | arch/mips/kernel/vmlinux.lds.S | 8 |
3 files changed, 50 insertions, 1 deletions
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 164d8c73552f..7cb5f6dbaeee 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -2677,6 +2677,33 @@ config USE_OF config BUILTIN_DTB bool +choice + prompt "Kernel appended dtb support" if OF + default MIPS_NO_APPENDED_DTB + + config MIPS_NO_APPENDED_DTB + bool "None" + help + Do not enable appended dtb support. + + config MIPS_RAW_APPENDED_DTB + bool "vmlinux.bin" + help + With this option, the boot code will look for a device tree binary + DTB) appended to raw vmlinux.bin (without decompressor). + (e.g. cat vmlinux.bin <filename>.dtb > vmlinux_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 vmlinux.bin. Do not leave this option active in a production kernel + if you don't intend to always append a DTB. +endchoice + endmenu config LOCKDEP_SUPPORT diff --git a/arch/mips/kernel/head.S b/arch/mips/kernel/head.S index 95afd663cd45..4e4cc5b9a771 100644 --- a/arch/mips/kernel/head.S +++ b/arch/mips/kernel/head.S @@ -94,6 +94,22 @@ NESTED(kernel_entry, 16, sp) # kernel entry point jr t0 0: +#ifdef CONFIG_MIPS_RAW_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 a1, t0 + PTR_LI a0, -2 +not_found: +#endif PTR_LA t0, __bss_start # clear .bss LONG_S zero, (t0) PTR_LA t1, __bss_stop - LONGSIZE diff --git a/arch/mips/kernel/vmlinux.lds.S b/arch/mips/kernel/vmlinux.lds.S index 3b46f7ce9ca7..07d32a4aea60 100644 --- a/arch/mips/kernel/vmlinux.lds.S +++ b/arch/mips/kernel/vmlinux.lds.S @@ -125,8 +125,14 @@ SECTIONS .exit.data : { EXIT_DATA } - +#ifdef CONFIG_SMP PERCPU_SECTION(1 << CONFIG_MIPS_L1_CACHE_SHIFT) +#endif +#ifdef CONFIG_MIPS_RAW_APPENDED_DTB + __appended_dtb = .; + /* leave space for appended DTB */ + . += 0x100000; +#endif /* * Align to 64K in attempt to eliminate holes before the * .bss..swapper_pg_dir section at the start of .bss. This |