powerpc: Separate PACA fields for server CPUs

This patch has no effect other than re-ordering PACA fields on
current server CPUs. It however is a pre-requisite for future
support of BookE 64-bit processors. Various parts of the PACA
struct are now moved under some ifdef's, either the new
CONFIG_PPC_BOOK3S or CONFIG_PPC_STD_MMU_64, whatever seems more
appropriate.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.craashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/include/asm/paca.h

@@ -43,6 +43,7 @@ struct task_struct;
  * processor.
  */
 struct paca_struct {
+#ifdef CONFIG_PPC_BOOK3S
 	/*
 	 * Because hw_cpu_id, unlike other paca fields, is accessed
 	 * routinely from other CPUs (from the IRQ code), we stick to
@@ -51,7 +52,7 @@ struct paca_struct {
 	 */
 
 	struct lppaca *lppaca_ptr;	/* Pointer to LpPaca for PLIC */
-
+#endif /* CONFIG_PPC_BOOK3S */
 	/*
 	 * MAGIC: the spinlock functions in arch/powerpc/lib/locks.c 
 	 * load lock_token and paca_index with a single lwz
@@ -64,13 +65,16 @@ struct paca_struct {
 	u64 kernel_toc;			/* Kernel TOC address */
 	u64 kernelbase;			/* Base address of kernel */
 	u64 kernel_msr;			/* MSR while running in kernel */
+#ifdef CONFIG_PPC_STD_MMU_64
 	u64 stab_real;			/* Absolute address of segment table */
 	u64 stab_addr;			/* Virtual address of segment table */
+#endif /* CONFIG_PPC_STD_MMU_64 */
 	void *emergency_sp;		/* pointer to emergency stack */
 	u64 data_offset;		/* per cpu data offset */
 	s16 hw_cpu_id;			/* Physical processor number */
 	u8 cpu_start;			/* At startup, processor spins until */
 					/* this becomes non-zero. */
+#ifdef CONFIG_PPC_STD_MMU_64
 	struct slb_shadow *slb_shadow_ptr;
 
 	/*
@@ -81,11 +85,13 @@ struct paca_struct {
 	u64 exmc[10];		/* used for machine checks */
 	u64 exslb[10];		/* used for SLB/segment table misses
  				 * on the linear mapping */
-
-	mm_context_t context;
+	/* SLB related definitions */
 	u16 vmalloc_sllp;
 	u16 slb_cache_ptr;
 	u16 slb_cache[SLB_CACHE_ENTRIES];
+#endif /* CONFIG_PPC_STD_MMU_64 */
+
+	mm_context_t context;
 
 	/*
 	 * then miscellaneous read-write fields