powerpc: Macros for saving/restore PPR
[PATCH 5/6] powerpc: Macros for saving/restore PPR
Several macros are defined for saving and restore user defined PPR value.
Signed-off-by: Haren Myneni <haren@us.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/exception-64s.h b/arch/powerpc/include/asm/exception-64s.h
index ed3cdcb..391e013 100644
--- a/arch/powerpc/include/asm/exception-64s.h
+++ b/arch/powerpc/include/asm/exception-64s.h
@@ -108,6 +108,43 @@
#define RESTORE_LR(reg, area)
#endif
+/*
+ * PPR save/restore macros used in exceptions_64s.S
+ * Used for P7 or later processors
+ */
+#define SAVE_PPR(area, ra, rb) \
+BEGIN_FTR_SECTION_NESTED(940) \
+ ld ra,PACACURRENT(r13); \
+ ld rb,area+EX_PPR(r13); /* Read PPR from paca */ \
+ std rb,TASKTHREADPPR(ra); \
+END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,CPU_FTR_HAS_PPR,940)
+
+#define RESTORE_PPR_PACA(area, ra) \
+BEGIN_FTR_SECTION_NESTED(941) \
+ ld ra,area+EX_PPR(r13); \
+ mtspr SPRN_PPR,ra; \
+END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,CPU_FTR_HAS_PPR,941)
+
+/*
+ * Increase the priority on systems where PPR save/restore is not
+ * implemented/ supported.
+ */
+#define HMT_MEDIUM_PPR_DISCARD \
+BEGIN_FTR_SECTION_NESTED(942) \
+ HMT_MEDIUM; \
+END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,0,942) /*non P7*/
+
+/*
+ * Save PPR in paca whenever some register is available to use.
+ * Then increase the priority.
+ */
+#define HMT_MEDIUM_PPR_SAVE(area, ra) \
+BEGIN_FTR_SECTION_NESTED(943) \
+ mfspr ra,SPRN_PPR; \
+ std ra,area+EX_PPR(r13); \
+ HMT_MEDIUM; \
+END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,CPU_FTR_HAS_PPR,943)
+
#define __EXCEPTION_PROLOG_1(area, extra, vec) \
GET_PACA(r13); \
std r9,area+EX_R9(r13); /* save r9 - r12 */ \