[PATCH v2 3/5] arm: decompressor: define a new zImage tag

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 3/5] arm: decompressor: define a new zImage tag
Date: Tue,  2 Jun 2020 18:17:29 +0200	[thread overview]
Message-ID: <20200602161731.23033-4-l.stelmach@samsung.com> (raw)
In-Reply-To: <20200602161731.23033-1-l.stelmach@samsung.com>

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

Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
---
 arch/arm/boot/compressed/vmlinux.lds.S | 9 ++++++++-
 arch/arm/include/asm/image.h           | 3 +++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/compressed/vmlinux.lds.S b/arch/arm/boot/compressed/vmlinux.lds.S
index 308e9cd6a897..d15c1269eb5d 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(3))
+    LONG(ARM_ZIMAGE_MAGIC4)
+    LONG(ZIMAGE_MAGIC((_end - __bss_start) +
+                      (_stack_end - _stack_start) +
+                      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..55b51faa6b7e 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__
 
@@ -40,6 +41,8 @@ struct arm_zimage_tag {
 			__le32 size_ptr;
 			__le32 bss_size;
 		} krnl_size;
+#define ZIMAGE_TAG_ZIMAGE_MEM ARM_ZIMAGE_MAGIC4
+		__le32 zimage_mem;
 	} u;
 };
 
-- 
2.26.2

