[PATCH v2 2/5] arm: add image header definitions

From: "Łukasz Stelmach" <l.stelmach@samsung.com>
To: Russell King <linux@armlinux.org.uk>,
	Masahiro Yamada <masahiroy@kernel.org>,
	Nick Desaulniers <ndesaulniers@google.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Enrico Weigelt <info@metux.net>,
	Kees Cook <keescook@chromium.org>, Ingo Molnar <mingo@kernel.org>,
	Ben Dooks <ben-linux@fluff.org>,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org
Cc: "AKASHI Takahiro" <takahiro.akashi@linaro.org>,
	"Bartlomiej Zolnierkiewicz" <b.zolnierkie@samsung.com>,
	"Marek Szyprowski" <m.szyprowski@samsung.com>,
	"Łukasz Stelmach" <l.stelmach@samsung.com>
Subject: [PATCH v2 2/5] arm: add image header definitions
Date: Tue,  2 Jun 2020 18:17:28 +0200	[thread overview]
Message-ID: <20200602161731.23033-3-l.stelmach@samsung.com> (raw)
In-Reply-To: <20200602161731.23033-1-l.stelmach@samsung.com>

This structure will be used later by kexec_file loader.

Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
---
 arch/arm/boot/compressed/head.S        |  3 +-
 arch/arm/boot/compressed/vmlinux.lds.S | 13 ++-----
 arch/arm/include/asm/image.h           | 48 ++++++++++++++++++++++++++
 3 files changed, 53 insertions(+), 11 deletions(-)
 create mode 100644 arch/arm/include/asm/image.h

diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S
index 55758264e776..005b172d504f 100644
--- a/arch/arm/boot/compressed/head.S
+++ b/arch/arm/boot/compressed/head.S
@@ -7,6 +7,7 @@
  */
 #include <linux/linkage.h>
 #include <asm/assembler.h>
+#include <asm/image.h>
 #include <asm/v7m.h>
 
 #include "efi-header.S"
@@ -211,7 +212,7 @@ start:
 		.word	_magic_start	@ absolute load/run zImage address
 		.word	_magic_end	@ zImage end address
 		.word	0x04030201	@ endianness flag
-		.word	0x45454545	@ another magic number to indicate
+		.word	ARM_ZIMAGE_MAGIC2 @ another magic number to indicate
 		.word	_magic_table	@ additional data table
 
 		__EFI_HEADER
diff --git a/arch/arm/boot/compressed/vmlinux.lds.S b/arch/arm/boot/compressed/vmlinux.lds.S
index f82b5962d97e..308e9cd6a897 100644
--- a/arch/arm/boot/compressed/vmlinux.lds.S
+++ b/arch/arm/boot/compressed/vmlinux.lds.S
@@ -3,14 +3,7 @@
  *  Copyright (C) 2000 Russell King
  */
 
-#ifdef CONFIG_CPU_ENDIAN_BE8
-#define ZIMAGE_MAGIC(x) ( (((x) >> 24) & 0x000000ff) | \
-			  (((x) >>  8) & 0x0000ff00) | \
-			  (((x) <<  8) & 0x00ff0000) | \
-			  (((x) << 24) & 0xff000000) )
-#else
-#define ZIMAGE_MAGIC(x) (x)
-#endif
+#include <asm/image.h>
 
 OUTPUT_ARCH(arm)
 ENTRY(_start)
@@ -43,7 +36,7 @@ SECTIONS
   .table : ALIGN(4) {
     _table_start = .;
     LONG(ZIMAGE_MAGIC(4))
-    LONG(ZIMAGE_MAGIC(0x5a534c4b))
+    LONG(ARM_ZIMAGE_MAGIC3)
     LONG(ZIMAGE_MAGIC(__piggy_size_addr - _start))
     LONG(ZIMAGE_MAGIC(_kernel_bss_size))
     LONG(0)
@@ -107,7 +100,7 @@ SECTIONS
     _edata_real = .;
   }
 
-  _magic_sig = ZIMAGE_MAGIC(0x016f2818);
+  _magic_sig = ARM_ZIMAGE_MAGIC1;
   _magic_start = ZIMAGE_MAGIC(_start);
   _magic_end = ZIMAGE_MAGIC(_edata);
   _magic_table = ZIMAGE_MAGIC(_table_start - _start);
diff --git a/arch/arm/include/asm/image.h b/arch/arm/include/asm/image.h
new file mode 100644
index 000000000000..d5c18a0f6a34
--- /dev/null
+++ b/arch/arm/include/asm/image.h
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __ASM_IMAGE_H
+#define __ASM_IMAGE_H
+
+#ifdef CONFIG_CPU_ENDIAN_BE8
+#define ZIMAGE_MAGIC(x) ((((x) >> 24) & 0x000000ff) | \
+			 (((x) >>  8) & 0x0000ff00) |  \
+			 (((x) <<  8) & 0x00ff0000) |  \
+			 (((x) << 24) & 0xff000000))
+#else
+#define ZIMAGE_MAGIC(x) (x)
+#endif
+
+#define ARM_ZIMAGE_MAGIC1 ZIMAGE_MAGIC(0x016f2818)
+#define ARM_ZIMAGE_MAGIC2 (0x45454545)
+#define ARM_ZIMAGE_MAGIC3 ZIMAGE_MAGIC(0x5a534c4b)
+
+#ifndef __ASSEMBLY__
+
+#include <linux/types.h>
+#include <asm/setup.h>
+
+/* ARM zImage header format */
+struct arm_zimage_header {
+	__le32 code[9];
+	__le32 magic;
+	__le32 start;
+	__le32 end;
+	__le32 endian;
+	__le32 magic2;
+	__le32 extension_tag_offset;
+};
+
+struct arm_zimage_tag {
+	struct tag_header hdr;
+	union {
+#define ZIMAGE_TAG_KRNL_SIZE ARM_ZIMAGE_MAGIC3
+		struct zimage_krnl_size {
+			__le32 size_ptr;
+			__le32 bss_size;
+		} krnl_size;
+	} u;
+};
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ASM_IMAGE_H */
-- 
2.26.2

