[POWERPC] Add DSCR SPR to sysfs

POWER6 adds a new SPR, the data stream control register (DSCR). It can
be used to adjust how agressive the prefetch mechanisms are.

Its possible we may want to context switch this, but for now just export
it to userspace via sysfs so we can adjust it.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 4 insertions, 2 deletions

diff --git a/include/asm-powerpc/cputable.h b/include/asm-powerpc/cputable.h
index 6fe5c9d4ca3b..782adbf1f7aa 100644
--- a/include/asm-powerpc/cputable.h
+++ b/include/asm-powerpc/cputable.h
@@ -152,6 +152,7 @@ extern void do_feature_fixups(unsigned long value, void *fixup_start,
 #define CPU_FTR_PURR                    LONG_ASM_CONST(0x0000400000000000)
 #define CPU_FTR_CELL_TB_BUG             LONG_ASM_CONST(0x0000800000000000)
 #define CPU_FTR_SPURR                   LONG_ASM_CONST(0x0001000000000000)
+#define CPU_FTR_DSCR                    LONG_ASM_CONST(0x0002000000000000)
 
 #ifndef __ASSEMBLY__
 
@@ -330,13 +331,14 @@ extern void do_feature_fixups(unsigned long value, void *fixup_start,
             CPU_FTR_HPTE_TABLE | CPU_FTR_PPCAS_ARCH_V2 | CPU_FTR_CTRL | \
             CPU_FTR_MMCRA | CPU_FTR_SMT | \
             CPU_FTR_COHERENT_ICACHE | CPU_FTR_LOCKLESS_TLBIE | \
-            CPU_FTR_PURR | CPU_FTR_SPURR | CPU_FTR_REAL_LE)
+            CPU_FTR_PURR | CPU_FTR_SPURR | CPU_FTR_REAL_LE | \
+            CPU_FTR_DSCR)
 #define CPU_FTRS_POWER6X (CPU_FTR_SPLIT_ID_CACHE | CPU_FTR_USE_TB | \
             CPU_FTR_HPTE_TABLE | CPU_FTR_PPCAS_ARCH_V2 | CPU_FTR_CTRL | \
             CPU_FTR_MMCRA | CPU_FTR_SMT | \
             CPU_FTR_COHERENT_ICACHE | CPU_FTR_LOCKLESS_TLBIE | \
             CPU_FTR_PURR | CPU_FTR_CI_LARGE_PAGE | \
-            CPU_FTR_SPURR | CPU_FTR_REAL_LE)
+            CPU_FTR_SPURR | CPU_FTR_REAL_LE | CPU_FTR_DSCR)
 #define CPU_FTRS_CELL   (CPU_FTR_SPLIT_ID_CACHE | CPU_FTR_USE_TB | \
             CPU_FTR_HPTE_TABLE | CPU_FTR_PPCAS_ARCH_V2 | CPU_FTR_CTRL | \
             CPU_FTR_ALTIVEC_COMP | CPU_FTR_MMCRA | CPU_FTR_SMT | \