[PATCH 3/5] arm: decompressor: define a new zImage tag

[Åukasz Stelmach]

Add DCSZ tag which holds dynamic memory (stack, bss, malloc pool)
requirements of the decompressor code.

Signed-off-by: Åukasz Stelmach <l.stelmach@xxxxxxxxxxx>
---
 arch/arm/boot/compressed/vmlinux.lds.S |  9 ++++++++-
 arch/arm/include/asm/image.h           | 13 +++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/compressed/vmlinux.lds.S b/arch/arm/boot/compressed/vmlinux.lds.S
index 308e9cd6a897..dcfdb3209c90 100644
--- a/arch/arm/boot/compressed/vmlinux.lds.S
+++ b/arch/arm/boot/compressed/vmlinux.lds.S
@@ -39,6 +39,11 @@ SECTIONS
     LONG(ARM_ZIMAGE_MAGIC3)
     LONG(ZIMAGE_MAGIC(__piggy_size_addr - _start))
     LONG(ZIMAGE_MAGIC(_kernel_bss_size))
+    LONG(ZIMAGE_MAGIC(5))
+    LONG(ARM_ZIMAGE_MAGIC4)
+    LONG(ZIMAGE_MAGIC(_end - __bss_start))
+    LONG(ZIMAGE_MAGIC(_stack_end - _stack_start))
+    LONG(ZIMAGE_MAGIC(_malloc_size))
     LONG(0)
     _table_end = .;
   }
@@ -108,10 +113,12 @@ SECTIONS
   . = BSS_START;
   __bss_start = .;
   .bss			: { *(.bss) }
+  . = ALIGN(8);		/* the stack must be 64-bit aligned and adjoin bss */
   _end = .;
 
-  . = ALIGN(8);		/* the stack must be 64-bit aligned */
+  _stack_start = .;
   .stack		: { *(.stack) }
+  _stack_end = .;
 
   PROVIDE(__pecoff_data_size = ALIGN(512) - ADDR(.data));
   PROVIDE(__pecoff_end = ALIGN(512));
diff --git a/arch/arm/include/asm/image.h b/arch/arm/include/asm/image.h
index d5c18a0f6a34..624438740f23 100644
--- a/arch/arm/include/asm/image.h
+++ b/arch/arm/include/asm/image.h
@@ -15,6 +15,7 @@
 #define ARM_ZIMAGE_MAGIC1 ZIMAGE_MAGIC(0x016f2818)
 #define ARM_ZIMAGE_MAGIC2 (0x45454545)
 #define ARM_ZIMAGE_MAGIC3 ZIMAGE_MAGIC(0x5a534c4b)
+#define ARM_ZIMAGE_MAGIC4 ZIMAGE_MAGIC(0x5a534344)
 
 #ifndef __ASSEMBLY__
 
@@ -43,6 +44,18 @@ struct arm_zimage_tag {
 	} u;
 };
 
+struct arm_zimage_tag_dc {
+	struct tag_header hdr;
+	union {
+#define ZIMAGE_TAG_DECOMP_SIZE ARM_ZIMAGE_MAGIC4
+		struct zimage_decomp_size {
+			__le32 bss_size;
+			__le32 stack_size;
+			__le32 malloc_size;
+		} decomp_size;
+	} u;
+};
+
 #endif /* __ASSEMBLY__ */
 
 #endif /* __ASM_IMAGE_H */
-- 
2.26.2