openwrt/target/linux/generic/pending-4.19/332-arc-add-OWRTDTB-section.patch
Evgeniy Didin 6c7b49c8b9 kernel: Update arc-add-OWRTDTB-section patch for 4.14
In 4.14.104 commit "e7264579eb80" (ARC: U-boot: check arguments paranoidly)
was introduced, which together with 332-arc-add-OWRTDTB-section.patch
caused build failure.

This commit updates 332-arc-add-OWRTDTB-section.patch.

Fixes:
http://phase1.builds.openwrt.org/builders/archs38%2Fgeneric/builds/1290
http://phase1.builds.openwrt.org/builders/archs38%2Fgeneric/builds/1269

Signed-off-by: Evgeniy Didin <evgeniy.didin@synopsys.com>
[Updated patch for kernel 4.19 in addition]
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Cc: John Crispin <john@phrozen.org>
2019-03-20 18:23:31 +01:00

85 lines
2.5 KiB
Diff

From 34ef04f3845ed2b47d57dd9d3b795b16e1f8185a Mon Sep 17 00:00:00 2001
From: Evgeniy Didin <Evgeniy.Didin@synopsys.com>
Date: Fri, 15 Mar 2019 18:53:38 +0300
Subject: [PATCH] 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: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Evgeniy Didin <Evgeniy.Didin@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
@@ -456,6 +456,8 @@ 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
@@ -469,7 +471,7 @@ 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)