[PATCH stable v4.9 24/35] powerpc/fsl: Add macro to flush the branch predictor

Michael Ellerman
2019-04-11T11:47:11Z

From: Diana Craciun <diana.craciun@nxp.com>

commit 1cbf8990d79ff69da8ad09e8a3df014e1494462b upstream.

The BUCSR register can be used to invalidate the entries in the
branch prediction mechanisms.

Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
arch/powerpc/include/asm/ppc_asm.h | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)

diff --git a/arch/powerpc/include/asm/ppc_asm.h b/arch/powerpc/include/asm/ppc_asm.h
index 24e95be3bfaf..bbd35ba36a22 100644
--- a/arch/powerpc/include/asm/ppc_asm.h
+++ b/arch/powerpc/include/asm/ppc_asm.h
@@ -780,4 +780,25 @@ END_FTR_SECTION_IFCLR(CPU_FTR_601)
.long 0x2400004c /* rfid */
#endif /* !CONFIG_PPC_BOOK3E */
#endif /* __ASSEMBLY__ */
+
+/*
+ * Helper macro for exception table entries
+ */
+#define EX_TABLE(_fault, _target) \
+ stringify_in_c(.section __ex_table,"a";)\
+ stringify_in_c(.balign 4;) \
+ stringify_in_c(.long (_fault) - . ;) \
+ stringify_in_c(.long (_target) - . ;) \
+ stringify_in_c(.previous)
+
+#ifdef CONFIG_PPC_FSL_BOOK3E
+#define BTB_FLUSH(reg) \
+ lis reg,BUCSR_INIT@h; \
+ ori reg,reg,BUCSR_INIT@l; \
+ mtspr SPRN_BUCSR,reg; \
+ isync;
+#else
+#define BTB_FLUSH(reg)
+#endif /* CONFIG_PPC_FSL_BOOK3E */
+
#endif /* _ASM_POWERPC_PPC_ASM_H */
--
2.20.1