[POWERPC] Tweak VDSO linker script to avoid upsetting old binutils

This works around bugs in older binutils' objcopy.
The placement of these sections does not really matter,
but it confused the buggy old BFD libraries.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

arch/powerpc/kernel/vdso64/vdso64.lds.S

@@ -43,15 +43,15 @@ SECTIONS
 	.rodata		: { *(.rodata .rodata.* .gnu.linkonce.r.*) }
 	.rodata1	: { *(.rodata1) }
 
+	.dynamic	: { *(.dynamic) }		:text	:dynamic
+
 	.eh_frame_hdr	: { *(.eh_frame_hdr) }		:text	:eh_frame_hdr
 	.eh_frame	: { KEEP (*(.eh_frame)) }	:text
 	.gcc_except_table : { *(.gcc_except_table) }
+	.rela.dyn ALIGN(8) : { *(.rela.dyn) }
 
 	.opd ALIGN(8)	: { KEEP (*(.opd)) }
 	.got ALIGN(8)	: { *(.got .toc) }
-	.rela.dyn ALIGN(8) : { *(.rela.dyn) }
-
-	.dynamic	: { *(.dynamic) }		:text	:dynamic
 
 	_end = .;
 	PROVIDE(end = .);

include/asm-powerpc/ppc_asm.h

@@ -356,6 +356,12 @@ END_FTR_SECTION_IFCLR(CPU_FTR_601)
 #define toreal(rd)
 #define fromreal(rd)
 
+/*
+ * We use addis to ensure compatibility with the "classic" ppc versions of
+ * these macros, which use rs = 0 to get the tophys offset in rd, rather than
+ * converting the address in r0, and so this version has to do that too
+ * (i.e. set register rd to 0 when rs == 0).
+ */
 #define tophys(rd,rs)				\
 	addis	rd,rs,0