arm64: Add macros to manage processor debug state

Add macros to enable and disable to manage PSTATE.D
for debugging. The macros local_dbg_save and local_dbg_restore
are moved to irqflags.h file

KGDB boot tests fail because of PSTATE.D is masked.
unmask it for debugging support

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/arch/arm64/include/asm/irqflags.h b/arch/arm64/include/asm/irqflags.h
index b2fcfbc51ecc..11cc941bd107 100644
--- a/arch/arm64/include/asm/irqflags.h
+++ b/arch/arm64/include/asm/irqflags.h
@@ -90,5 +90,28 @@ static inline int arch_irqs_disabled_flags(unsigned long flags)
         return flags & PSR_I_BIT;
 }
 
+/*
+ * save and restore debug state
+ */
+#define local_dbg_save(flags)                                           \
+        do {                                                            \
+                typecheck(unsigned long, flags);                        \
+                asm volatile(                                           \
+                "mrs    %0, daif                // local_dbg_save\n"    \
+                "msr    daifset, #8"                                    \
+                : "=r" (flags) : : "memory");                           \
+        } while (0)
+
+#define local_dbg_restore(flags)                                        \
+        do {                                                            \
+                typecheck(unsigned long, flags);                        \
+                asm volatile(                                           \
+                "msr    daif, %0                // local_dbg_restore\n" \
+                : : "r" (flags) : "memory");                            \
+        } while (0)
+
+#define local_dbg_enable()      asm("msr        daifclr, #8" : : : "memory")
+#define local_dbg_disable()     asm("msr        daifset, #8" : : : "memory")
+
 #endif
 #endif