[POWERPC] Update linker script to properly set physical addresses

We can set LOAD_OFFSET and use the AT attribute on sections and the
linker will properly set the physical address of the LOAD program
header for us.

This allows us to know how the PHYSICAL_START the user configured a
kernel with by just looking at the resulting vmlinux ELF.

This is pretty much stolen from how x86 does things in their linker
scripts.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S
index b5a76bcd95a6437b76630589b9f0d9740877db53..0c3000bf8d75d8919e20df3e44ba9a99d7bb7d14 100644 (file)
--- a/arch/powerpc/kernel/vmlinux.lds.S
+++ b/arch/powerpc/kernel/vmlinux.lds.S
@@ -31,7 +31,7 @@ SECTIONS
  */
 
        /* Text and gots */
-       .text : {
+       .text : AT(ADDR(.text) - LOAD_OFFSET) {
                ALIGN_FUNCTION();
                *(.text.head)
                _text = .;
@@ -56,7 +56,7 @@ SECTIONS
        RODATA
 
        /* Exception & bug tables */
-       __ex_table : {
+       __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
                __start___ex_table = .;
                *(__ex_table)
                __stop___ex_table = .;
@@ -72,7 +72,7 @@ SECTIONS
        . = ALIGN(PAGE_SIZE);
        __init_begin = .;
 
-       .init.text : {
+       .init.text : AT(ADDR(.init.text) - LOAD_OFFSET) {
                _sinittext = .;
                INIT_TEXT
                _einittext = .;
@@ -81,11 +81,11 @@ SECTIONS
        /* .exit.text is discarded at runtime, not link time,
         * to deal with references from __bug_table
         */
-       .exit.text : {
+       .exit.text : AT(ADDR(.exit.text) - LOAD_OFFSET) {
                EXIT_TEXT
        }
 
-       .init.data : {
+       .init.data : AT(ADDR(.init.data) - LOAD_OFFSET) {
                INIT_DATA
                __vtop_table_begin = .;
                *(.vtop_fixup);
@@ -101,19 +101,19 @@ SECTIONS
        }
 
        . = ALIGN(16);
-       .init.setup : {
+       .init.setup : AT(ADDR(.init.setup) - LOAD_OFFSET) {
                __setup_start = .;
                *(.init.setup)
                __setup_end = .;
        }
 
-       .initcall.init : {
+       .initcall.init : AT(ADDR(.initcall.init) - LOAD_OFFSET) {
                __initcall_start = .;
                INITCALLS
                __initcall_end = .;
                }
 
-       .con_initcall.init : {
+       .con_initcall.init : AT(ADDR(.con_initcall.init) - LOAD_OFFSET) {
                __con_initcall_start = .;
                *(.con_initcall.init)
                __con_initcall_end = .;
@@ -122,14 +122,14 @@ SECTIONS
        SECURITY_INIT
 
        . = ALIGN(8);
-       __ftr_fixup : {
+       __ftr_fixup : AT(ADDR(__ftr_fixup) - LOAD_OFFSET) {
                __start___ftr_fixup = .;
                *(__ftr_fixup)
                __stop___ftr_fixup = .;
        }
 #ifdef CONFIG_PPC64
        . = ALIGN(8);
-       __fw_ftr_fixup : {
+       __fw_ftr_fixup : AT(ADDR(__fw_ftr_fixup) - LOAD_OFFSET) {
                __start___fw_ftr_fixup = .;
                *(__fw_ftr_fixup)
                __stop___fw_ftr_fixup = .;
@@ -137,14 +137,14 @@ SECTIONS
 #endif
 #ifdef CONFIG_BLK_DEV_INITRD
        . = ALIGN(PAGE_SIZE);
-       .init.ramfs : {
+       .init.ramfs : AT(ADDR(.init.ramfs) - LOAD_OFFSET) {
                __initramfs_start = .;
                *(.init.ramfs)
                __initramfs_end = .;
        }
 #endif
        . = ALIGN(PAGE_SIZE);
-       .data.percpu : {
+       .data.percpu  : AT(ADDR(.data.percpu) - LOAD_OFFSET) {
                __per_cpu_start = .;
                *(.data.percpu)
                *(.data.percpu.shared_aligned)
@@ -152,7 +152,7 @@ SECTIONS
        }
 
        . = ALIGN(8);
-       .machine.desc : {
+       .machine.desc : AT(ADDR(.machine.desc) - LOAD_OFFSET) {
                __machine_desc_start = . ;
                *(.machine.desc)
                __machine_desc_end = . ;
@@ -170,25 +170,24 @@ SECTIONS
        _sdata = .;
 
 #ifdef CONFIG_PPC32
-       .data    :
-       {
+       .data : AT(ADDR(.data) - LOAD_OFFSET) {
                DATA_DATA
                *(.sdata)
                *(.got.plt) *(.got)
        }
 #else
-       .data : {
+       .data : AT(ADDR(.data) - LOAD_OFFSET) {
                DATA_DATA
                *(.data.rel*)
                *(.toc1)
                *(.branch_lt)
        }
 
-       .opd : {
+       .opd : AT(ADDR(.opd) - LOAD_OFFSET) {
                *(.opd)
        }
 
-       .got : {
+       .got : AT(ADDR(.got) - LOAD_OFFSET) {
                __toc_start = .;
                *(.got)
                *(.toc)
@@ -205,26 +204,26 @@ SECTIONS
 #else
        . = ALIGN(16384);
 #endif
-       .data.init_task : {
+       .data.init_task : AT(ADDR(.data.init_task) - LOAD_OFFSET) {
                *(.data.init_task)
        }
 
        . = ALIGN(PAGE_SIZE);
-       .data.page_aligned : {
+       .data.page_aligned : AT(ADDR(.data.page_aligned) - LOAD_OFFSET) {
                *(.data.page_aligned)
        }
 
-       .data.cacheline_aligned : {
+       .data.cacheline_aligned : AT(ADDR(.data.cacheline_aligned) - LOAD_OFFSET) {
                *(.data.cacheline_aligned)
        }
 
        . = ALIGN(L1_CACHE_BYTES);
-       .data.read_mostly : {
+       .data.read_mostly : AT(ADDR(.data.read_mostly) - LOAD_OFFSET) {
                *(.data.read_mostly)
        }
 
        . = ALIGN(PAGE_SIZE);
-       __data_nosave : {
+       .data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) {
                __nosave_begin = .;
                *(.data.nosave)
                . = ALIGN(PAGE_SIZE);
@@ -235,7 +234,7 @@ SECTIONS
  * And finally the bss
  */
 
-       .bss : {
+       .bss : AT(ADDR(.bss) - LOAD_OFFSET) {
                __bss_start = .;
                *(.sbss) *(.scommon)
                *(.dynbss)

diff --git a/include/asm-powerpc/page.h b/include/asm-powerpc/page.h
index df47bbb6ea1348e6c6ad95898baa911e819823b7..6c850609b847c01900db5ec9fdb7f40cce92eede 100644 (file)
--- a/include/asm-powerpc/page.h
+++ b/include/asm-powerpc/page.h
@@ -53,6 +53,7 @@
 
 #define PAGE_OFFSET     ASM_CONST(CONFIG_KERNEL_START)
 #define KERNELBASE      (PAGE_OFFSET + PHYSICAL_START)
+#define LOAD_OFFSET    PAGE_OFFSET
 
 #ifdef CONFIG_FLATMEM
 #define pfn_valid(pfn)         ((pfn) < max_mapnr)