[PATCH 02/11] x86/xip: Update address of sections in linker script

[Jim Kukunas]

In order to update the LMA for each section, according to
CONFIG_XIP_BASE, this patch uses the preprocessor to change
the arguments passed to the AT keyword. Each LMA is updated
to that symbol's physical address.

The text section is aligned to a page so that the ELF
header at the beginning of XIP_BASE isn't mapped into
the linear address space. Also the initial location counter
is incremented to account for the ELF header.

Signed-off-by: Jim Kukunas <james.t.kukunas@xxxxxxxxxxxxxxx>
---
 arch/x86/include/asm/boot.h   |  4 ++++
 arch/x86/kernel/vmlinux.lds.S | 17 +++++++++++++++--
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/boot.h b/arch/x86/include/asm/boot.h
index 4fa687a..a128c71 100644
--- a/arch/x86/include/asm/boot.h
+++ b/arch/x86/include/asm/boot.h
@@ -10,6 +10,10 @@
 				+ (CONFIG_PHYSICAL_ALIGN - 1)) \
 				& ~(CONFIG_PHYSICAL_ALIGN - 1))
 
+#ifdef CONFIG_XIP_KERNEL
+#define PHYS_XIP_OFFSET (CONFIG_XIP_BASE - (LOAD_OFFSET + LOAD_PHYSICAL_ADDR))
+#endif
+
 /* Minimum kernel alignment, as a power of two */
 #ifdef CONFIG_X86_64
 #define MIN_KERNEL_ALIGN_LG2	PMD_SHIFT
diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 00bf300..414a1ac 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -20,6 +20,15 @@
 #define LOAD_OFFSET __START_KERNEL_map
 #endif
 
+#ifdef CONFIG_XIP_KERNEL
+#define AT(x)	AT(x + LOAD_OFFSET + PHYS_XIP_OFFSET)
+#define TEXT_ALIGN	ALIGN(0x1000)
+#define DATA_ALIGN	ALIGN(0x200000)
+#else
+#define TEXT_ALIGN
+#define DATA_ALIGN
+#endif
+
 #include <asm-generic/vmlinux.lds.h>
 #include <asm/asm-offsets.h>
 #include <asm/thread_info.h>
@@ -89,8 +98,12 @@ SECTIONS
         phys_startup_64 = startup_64 - LOAD_OFFSET;
 #endif
 
+#ifdef CONFIG_XIP_KERNEL
+	. += SIZEOF_HEADERS;
+#endif
+
 	/* Text and read-only data */
-	.text :  AT(ADDR(.text) - LOAD_OFFSET) {
+	.text :  AT(ADDR(.text) - LOAD_OFFSET) TEXT_ALIGN {
 		_text = .;
 		/* bootstrapping code */
 		HEAD_TEXT
@@ -121,7 +134,7 @@ SECTIONS
 	X64_ALIGN_DEBUG_RODATA_END
 
 	/* Data */
-	.data : AT(ADDR(.data) - LOAD_OFFSET) {
+	.data : AT(ADDR(.data) - LOAD_OFFSET) DATA_ALIGN {
 		/* Start of data section */
 		_sdata = .;
 
-- 
2.1.0

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