[POWERPC] cell: add spu_64k_pages_available() check

Add a function spu_64k_pages_available(), so that we can abstract the
explicity use of mmu_psize_defs() in lssca_alloc.c
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arch/powerpc/platforms/cell/spu_base.c

@@ -126,6 +126,12 @@ void spu_associate_mm(struct spu *spu, struct mm_struct *mm)
 }
 EXPORT_SYMBOL_GPL(spu_associate_mm);
 
+int spu_64k_pages_available(void)
+{
+	return mmu_psize_defs[MMU_PAGE_64K].shift != 0;
+}
+EXPORT_SYMBOL_GPL(spu_64k_pages_available);
+
 static int __spu_trap_invalid_dma(struct spu *spu)
 {
 	pr_debug("%s\n", __FUNCTION__);

arch/powerpc/platforms/cell/spufs/lscsa_alloc.c

@@ -73,7 +73,7 @@ int spu_alloc_lscsa(struct spu_state *csa)
 	int		i, j, n_4k;
 
 	/* Check availability of 64K pages */
-	if (mmu_psize_defs[MMU_PAGE_64K].shift == 0)
+	if (!spu_64k_pages_available())
 		goto fail;
 
 	csa->use_big_pages = 1;

include/asm-powerpc/spu.h

@@ -214,6 +214,7 @@ static inline void crash_register_spus(struct list_head *list)
 
 extern void spu_invalidate_slbs(struct spu *spu);
 extern void spu_associate_mm(struct spu *spu, struct mm_struct *mm);
+int spu_64k_pages_available(void);
 
 /* Calls from the memory management to the SPU */
 struct mm_struct;