[PATCH 3/12] ppc64: Remove unused reloc_offset code

[Michael Ellerman]

In head.S there are several routines that are written to use reloc_offset,
so they can run at a different address to their link address. However, some
of these routines are only ever called after the kernel's moved to it's linked
address, and so the reloc_offset business is redundant.

This patch changes the calling convention for cpu_setup routines, but currently
none of them actually consult their arguments so no further changes are
needed.

Signed-off-by: Michael Ellerman <michael at ellerman.id.au>
---

 arch/ppc64/kernel/head.S |   13 -------------
 arch/ppc64/kernel/misc.S |   10 ++--------
 2 files changed, 2 insertions(+), 21 deletions(-)

Index: work/arch/ppc64/kernel/head.S
===================================================================
--- work.orig/arch/ppc64/kernel/head.S
+++ work/arch/ppc64/kernel/head.S
@@ -1342,7 +1342,6 @@ _STATIC(__start_initialization_iSeries)
 
 	LOADADDR(r3,cpu_specs)
 	LOADADDR(r4,cur_cpu_spec)
-	li	r5,0
 	bl	.identify_cpu
 
 	LOADADDR(r2,__toc_start)
@@ -1689,10 +1688,6 @@ _GLOBAL(enable_64b_mode)
  * This is where the main kernel code starts.
  */
 _STATIC(start_here_multiplatform)
-	/* get a new offset, now that the kernel has moved. */
-	bl	.reloc_offset
-	mr	r26,r3
-
 	/* Clear out the BSS. It may have been done in prom_init,
 	 * already but that's irrelevant since prom_init will soon
 	 * be detached from the kernel completely. Besides, we need
@@ -1738,7 +1733,6 @@ _STATIC(start_here_multiplatform)
 	/* kernel but are still running in real mode. */
 
 	LOADADDR(r3,init_thread_union)
-	sub	r3,r3,r26
 
 	/* set up a stack pointer (physical address) */
 	addi	r1,r3,THREAD_SIZE
@@ -1749,13 +1743,9 @@ _STATIC(start_here_multiplatform)
 	LOADADDR(r2,__toc_start)
 	addi	r2,r2,0x4000
 	addi	r2,r2,0x4000
-	sub	r2,r2,r26
 
 	LOADADDR(r3,cpu_specs)
-	sub	r3,r3,r26
 	LOADADDR(r4,cur_cpu_spec)
-	sub	r4,r4,r26
-	mr	r5,r26
 	bl	.identify_cpu
 
 	/* Save some low level config HIDs of CPU0 to be copied to
@@ -1770,13 +1760,11 @@ _STATIC(start_here_multiplatform)
 	 * code
 	 */
 	LOADADDR(r27, boot_cpuid)
-	sub	r27,r27,r26
 	lwz	r27,0(r27)
 
 	LOADADDR(r24, paca) 		/* Get base vaddr of paca array	 */
 	mulli	r13,r27,PACA_SIZE	/* Calculate vaddr of right paca */
 	add	r13,r13,r24		/* for this processor.		 */
-	sub	r13,r13,r26		/* convert to physical addr	 */
 	mtspr	SPRG3,r13		/* PPPBBB: Temp... -Peter */
 	
 	/* Do very early kernel initializations, including initial hash table,
@@ -1814,7 +1802,6 @@ _STATIC(start_here_multiplatform)
 	andi.	r3,r3,0x1
 	bne	98f
 	LOADADDR(r6,_SDR1)		/* Only if NOT LPAR */
-	sub	r6,r6,r26
 	ld	r6,0(r6)		/* get the value of _SDR1 */
 	mtspr	SDR1,r6			/* set the htab location  */
 98: 
Index: work/arch/ppc64/kernel/misc.S
===================================================================
--- work.orig/arch/ppc64/kernel/misc.S
+++ work/arch/ppc64/kernel/misc.S
@@ -511,7 +511,6 @@ _GLOBAL(cvt_df)
  * identify_cpu and calls setup_cpu
  * In:	r3 = base of the cpu_specs array
  *	r4 = address of cur_cpu_spec
- *	r5 = relocation offset
  */
 _GLOBAL(identify_cpu)
 	mfpvr	r7
@@ -524,16 +523,11 @@ _GLOBAL(identify_cpu)
 	addi	r3,r3,CPU_SPEC_ENTRY_SIZE
 	b	1b
 1:
-	add	r0,r3,r5
-	std	r0,0(r4)
+	std	r3,0(r4)
 	ld	r4,CPU_SPEC_SETUP(r3)
-	sub	r4,r4,r5
 	ld	r4,0(r4)
-	sub	r4,r4,r5
 	mtctr	r4
-	/* Calling convention for cpu setup is r3=offset, r4=cur_cpu_spec */
-	mr	r4,r3
-	mr	r3,r5
+	/* Calling convention for cpu setup is r3 = cur_cpu_spec */
 	bctr
 
 /*