New hazard handling function back_to_back_c0_hazard() to handle back to

back mtc0 / mfc0 pairs from the same coprocessor register.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 21 insertions, 0 deletions

diff --git a/include/asm-mips/hazards.h b/include/asm-mips/hazards.h
index f524eaccd5f1..d6e88cf06ba9 100644
--- a/include/asm-mips/hazards.h
+++ b/include/asm-mips/hazards.h
@@ -124,6 +124,9 @@ __asm__(
                 ".set\tmips32\n\t"                                      \
                 "_ssnop; _ssnop; _ssnop; _ssnop\n\t"                    \
                 ".set\tmips0")
+
+#define back_to_back_c0_hazard()        do { } while (0)
+
 #else
 
 /*
@@ -141,6 +144,12 @@ __asm__(
                 "nop; nop; nop; nop; nop; nop;\n\t"                     \
                 ".set reorder\n\t")
 
+#define back_to_back_c0_hazard()                                        \
+        __asm__ __volatile__(                                           \
+        "       .set noreorder                          \n"             \
+        "       nop; nop; nop                           \n"             \
+        "       .set reorder                            \n")
+
 #endif
 
 /*
@@ -170,6 +179,10 @@ __asm__(
         __asm__ __volatile__(                                           \
         "_ehb\t\t\t\t# irq_disable_hazard")
 
+#define back_to_back_c0_hazard()                                        \
+        __asm__ __volatile__(                                           \
+        "_ehb\t\t\t\t# back_to_back_c0_hazard")
+
 #elif defined(CONFIG_CPU_R10000) || defined(CONFIG_CPU_RM9000)
 
 /*
@@ -186,6 +199,8 @@ __asm__(
 #define irq_enable_hazard()     do { } while (0)
 #define irq_disable_hazard()    do { } while (0)
 
+#define back_to_back_c0_hazard()        do { } while (0)
+
 #else
 
 /*
@@ -210,6 +225,12 @@ __asm__(
         __asm__ __volatile__(                                           \
         "_ssnop; _ssnop; _ssnop;\t\t# irq_disable_hazard")
 
+#define back_to_back_c0_hazard()                                        \
+        __asm__ __volatile__(                                           \
+        "       .set noreorder                          \n"             \
+        "       nop; nop; nop                           \n"             \
+        "       .set reorder                            \n")
+
 #endif
 
 #endif /* __ASSEMBLY__ */