powerpc/4xx: Extended DCR support v2

This adds supports to the "extended" DCR addressing via the indirect
mfdcrx/mtdcrx instructions supported by some 4xx cores (440H6 and
later).

I enabled the feature for now only on AMCC 460 chips.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 5 insertions, 2 deletions

diff --git a/arch/powerpc/include/asm/cputable.h b/arch/powerpc/include/asm/cputable.h
index f3d9d7417166..31888322d76a 100644
--- a/arch/powerpc/include/asm/cputable.h
+++ b/arch/powerpc/include/asm/cputable.h
@@ -164,6 +164,7 @@ extern const char *powerpc_base_platform;
 #define CPU_FTR_NEED_PAIRED_STWCX       ASM_CONST(0x0000000004000000)
 #define CPU_FTR_LWSYNC                  ASM_CONST(0x0000000008000000)
 #define CPU_FTR_NOEXECUTE               ASM_CONST(0x0000000010000000)
+#define CPU_FTR_INDEXED_DCR             ASM_CONST(0x0000000020000000)
 
 /*
  * Add the 64-bit processor unique features in the top half of the word;
@@ -369,6 +370,8 @@ extern const char *powerpc_base_platform;
 #define CPU_FTRS_8XX    (CPU_FTR_USE_TB)
 #define CPU_FTRS_40X    (CPU_FTR_USE_TB | CPU_FTR_NODSISRALIGN | CPU_FTR_NOEXECUTE)
 #define CPU_FTRS_44X    (CPU_FTR_USE_TB | CPU_FTR_NODSISRALIGN | CPU_FTR_NOEXECUTE)
+#define CPU_FTRS_440x6  (CPU_FTR_USE_TB | CPU_FTR_NODSISRALIGN | CPU_FTR_NOEXECUTE | \
+            CPU_FTR_INDEXED_DCR)
 #define CPU_FTRS_E200   (CPU_FTR_USE_TB | CPU_FTR_SPE_COMP | \
             CPU_FTR_NODSISRALIGN | CPU_FTR_COHERENT_ICACHE | \
             CPU_FTR_UNIFIED_ID_CACHE | CPU_FTR_NOEXECUTE)
@@ -455,7 +458,7 @@ enum {
             CPU_FTRS_40X |
 #endif
 #ifdef CONFIG_44x
-            CPU_FTRS_44X |
+            CPU_FTRS_44X | CPU_FTRS_440x6 |
 #endif
 #ifdef CONFIG_E200
             CPU_FTRS_E200 |
@@ -495,7 +498,7 @@ enum {
             CPU_FTRS_40X &
 #endif
 #ifdef CONFIG_44x
-            CPU_FTRS_44X &
+            CPU_FTRS_44X & CPU_FTRS_440x6 &
 #endif
 #ifdef CONFIG_E200
             CPU_FTRS_E200 &