MIPS: ZBOOT: copy appended dtb to the end of the kernel

Instead of rewriting the arguments, just move the appended dtb to where
the decompressed kernel expects it. This eliminates the need for special
casing vmlinuz.bin appended dtb files.

Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: John Crispin <john@phrozen.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Alban Bedel <albeu@free.fr>
Cc: Daniel Gimpelevich <daniel@gimpelevich.san-francisco.ca.us>
Cc: Antony Pavlov <antonynpavlov@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13698/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
Jonas Gorski 2016-06-20 11:27:36 +02:00 committed by Ralf Baechle
parent 7997789461
commit b8f54f2cde
3 changed files with 19 additions and 36 deletions

View File

@ -2884,10 +2884,10 @@ choice
the documented boot protocol using a device tree.
config MIPS_RAW_APPENDED_DTB
bool "vmlinux.bin"
bool "vmlinux.bin or vmlinuz.bin"
help
With this option, the boot code will look for a device tree binary
DTB) appended to raw vmlinux.bin (without decompressor).
DTB) appended to raw vmlinux.bin or vmlinuz.bin.
(e.g. cat vmlinux.bin <filename>.dtb > vmlinux_w_dtb).
This is meant as a backward compatibility convenience for those
@ -2899,24 +2899,6 @@ 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
choice

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@ -14,6 +14,7 @@
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/libfdt.h>
#include <asm/addrspace.h>
@ -36,6 +37,8 @@ extern void puthex(unsigned long long val);
#define puthex(val) do {} while (0)
#endif
extern char __appended_dtb[];
void error(char *x)
{
puts("\n\n");
@ -114,6 +117,20 @@ void decompress_kernel(unsigned long boot_heap_start)
__decompress((char *)zimage_start, zimage_size, 0, 0,
(void *)VMLINUX_LOAD_ADDRESS_ULL, 0, 0, error);
if (IS_ENABLED(CONFIG_MIPS_RAW_APPENDED_DTB) &&
fdt_magic((void *)&__appended_dtb) == FDT_MAGIC) {
unsigned int image_size, dtb_size;
dtb_size = fdt_totalsize((void *)&__appended_dtb);
/* last four bytes is always image size in little endian */
image_size = le32_to_cpup((void *)&__image_end - 4);
/* copy dtb to where the booted kernel will expect it */
memcpy((void *)VMLINUX_LOAD_ADDRESS_ULL + image_size,
__appended_dtb, dtb_size);
}
/* FIXME: should we flush cache here? */
puts("Now, booting the kernel...\n");
}

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@ -25,22 +25,6 @@ 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