openwrtv4/target/linux/generic/pending-4.14/332-arc-add-OWRTDTB-section.patch
Hauke Mehrtens b3f95490b9 kernel: generic: Add kernel 4.14 support
This adds initial support for kernel 4.14 based on the patches for
kernel 4.9.

In the configuration I deactivated some of the new possible security
features like:
CONFIG_REFCOUNT_FULL
CONFIG_SLAB_FREELIST_HARDENED
CONFIG_SOFTLOCKUP_DETECTOR
CONFIG_WARN_ALL_UNSEEDED_RANDOM

And these overlay FS options are also deactivated:
CONFIG_OVERLAY_FS_INDEX
CONFIG_OVERLAY_FS_REDIRECT_DIR

I activated this:
CONFIG_FORTIFY_SOURCE
CONFIG_POSIX_TIMERS
CONFIG_SLAB_MERGE_DEFAULT
CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED

I am not sure if I did the porting correct for the following patches:
target/linux/generic/backport-4.14/020-backport_netfilter_rtcache.patch
target/linux/generic/hack-4.14/220-gc_sections.patch
target/linux/generic/hack-4.14/321-powerpc_crtsavres_prereq.patch
target/linux/generic/pending-4.14/305-mips_module_reloc.patch
target/linux/generic/pending-4.14/611-netfilter_match_bypass_default_table.patch
target/linux/generic/pending-4.14/680-NET-skip-GRO-for-foreign-MAC-addresses.patch

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
2017-12-16 22:11:19 +01:00

80 lines
2.2 KiB
Diff

From: Alexey Brodkin <abrodkin@synopsys.com>
Subject: openwrt: arc - add OWRTDTB section
This change allows OpenWRT to patch resulting kernel binary with
external .dtb.
That allows us to re-use exactky the same vmlinux on different boards
given its ARC core configurations match (at least cache line sizes etc).
""patch-dtb" searches for ASCII "OWRTDTB:" strign and copies external
.dtb right after it, keeping the string in place.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
---
arch/arc/kernel/head.S | 10 ++++++++++
arch/arc/kernel/setup.c | 4 +++-
arch/arc/kernel/vmlinux.lds.S | 13 +++++++++++++
3 files changed, 26 insertions(+), 1 deletion(-)
--- a/arch/arc/kernel/head.S
+++ b/arch/arc/kernel/head.S
@@ -49,6 +49,16 @@
1:
.endm
+; Here "patch-dtb" will embed external .dtb
+; Note "patch-dtb" searches for ASCII "OWRTDTB:" string
+; and pastes .dtb right after it, hense the string precedes
+; __image_dtb symbol.
+ .section .owrt, "aw",@progbits
+ .ascii "OWRTDTB:"
+ENTRY(__image_dtb)
+ .fill 0x4000
+END(__image_dtb)
+
.section .init.text, "ax",@progbits
;----------------------------------------------------------------
--- a/arch/arc/kernel/setup.c
+++ b/arch/arc/kernel/setup.c
@@ -421,6 +421,8 @@ static inline int is_kernel(unsigned lon
return 0;
}
+extern struct boot_param_header __image_dtb;
+
void __init setup_arch(char **cmdline_p)
{
#ifdef CONFIG_ARC_UBOOT_SUPPORT
@@ -434,7 +436,7 @@ void __init setup_arch(char **cmdline_p)
#endif
{
/* No, so try the embedded one */
- machine_desc = setup_machine_fdt(__dtb_start);
+ machine_desc = setup_machine_fdt(&__image_dtb);
if (!machine_desc)
panic("Embedded DT invalid\n");
--- a/arch/arc/kernel/vmlinux.lds.S
+++ b/arch/arc/kernel/vmlinux.lds.S
@@ -30,6 +30,19 @@ SECTIONS
. = CONFIG_LINUX_LINK_BASE;
+ /*
+ * In OpenWRT we want to patch built binary embedding .dtb of choice.
+ * This is implemented with "patch-dtb" utility which searches for
+ * "OWRTDTB:" string in first 16k of image and if it is found
+ * copies .dtb right after mentioned string.
+ *
+ * Note: "OWRTDTB:" won't be overwritten with .dtb, .dtb will follow it.
+ */
+ .owrt : {
+ *(.owrt)
+ . = ALIGN(PAGE_SIZE);
+ }
+
_int_vec_base_lds = .;
.vector : {
*(.vector)