[PATCH v3 43/70] powerpc/mm/radix: Add MMU_FTR_RADIX

[Michael Ellerman]

From: "Aneesh Kumar K.V" <aneesh.kumar at linux.vnet.ibm.com>

We are going to add asm changes in the follow up patches. Add the
feature bit now so that we can get it all build.

mpe: Note that if CONFIG_PPC_RADIX_MMU=n we define MMU_FTR_RADIX to
zero. This has the effect of turning all the radix_enabled() checks into
if (0), which the compiler is smart enough to elide completely.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora at gmail.com>
Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
---
 arch/powerpc/include/asm/book3s/64/mmu.h | 3 ++-
 arch/powerpc/include/asm/mmu.h           | 9 +++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h
index 94d52ff49bbe..5854263d4d6e 100644
--- a/arch/powerpc/include/asm/book3s/64/mmu.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu.h
@@ -23,7 +23,8 @@ struct mmu_psize_def {
 };
 extern struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT];
 
-#define radix_enabled() (0)
+#define radix_enabled() mmu_has_feature(MMU_FTR_RADIX)
+
 #endif /* __ASSEMBLY__ */
 
 /* 64-bit classic hash table MMU */
diff --git a/arch/powerpc/include/asm/mmu.h b/arch/powerpc/include/asm/mmu.h
index 34070e982f1d..d91dc886c90f 100644
--- a/arch/powerpc/include/asm/mmu.h
+++ b/arch/powerpc/include/asm/mmu.h
@@ -88,6 +88,15 @@
  */
 #define MMU_FTR_1T_SEGMENT		ASM_CONST(0x40000000)
 
+/*
+ * Radix page table available
+ */
+#ifdef CONFIG_PPC_RADIX_MMU
+#define MMU_FTR_RADIX                  ASM_CONST(0x80000000)
+#else
+#define MMU_FTR_RADIX                  ASM_CONST(0)
+#endif
+
 /* MMU feature bit sets for various CPUs */
 #define MMU_FTRS_DEFAULT_HPTE_ARCH_V2	\
 	MMU_FTR_HPTE_TABLE | MMU_FTR_PPCAS_ARCH_V2
-- 
2.5.0