From d9676fa152c83b82137af950b1d4f629045d90c9 Mon Sep 17 00:00:00 2001
From: Evgeny Voevodin <evgeny.voevodin@intel.com>
Date: Wed, 23 Mar 2016 12:26:52 +0300
Subject: [PATCH] ARCv2: Enable LOCKDEP
- The asm helpers for calling into irq tracer were missing
- Add calls to above helpers in low level assembly entry code for ARCv2
- irq_save() uses CLRI to disable interrupts and returns the prev interrupt
state (in STATUS32) in a specific encoding (and not the raw value of
STATUS32). This is usable with SETI in irq_restore(). However
save_flags() reads the raw value of STATUS32 which doesn't pair with
irq_save/restore() and thus needs fixing.
Signed-off-by: Evgeny Voevodin <evgeny.voevodin@intel.com>
[vgupta: updated changelog and also added some comments]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
---
arch/arc/include/asm/irqflags-arcv2.h | 36 ++++++++++++++++++++++++++-
arch/arc/kernel/entry-arcv2.S | 10 +++++++-
arch/arc/kernel/entry-compact.S | 3 +++
3 files changed, 47 insertions(+), 2 deletions(-)
diff --git a/arch/arc/include/asm/irqflags-arcv2.h b/arch/arc/include/asm/irqflags-arcv2.h
index 37c2f751eebf0..d1ec7f6b31e0d 100644
--- a/arch/arc/include/asm/irqflags-arcv2.h
+++ b/arch/arc/include/asm/irqflags-arcv2.h
@@ -18,6 +18,12 @@
#define STATUS_AD_MASK (1<<STATUS_AD_BIT)
#define STATUS_IE_MASK (1<<STATUS_IE_BIT)
+/* status32 Bits as encoded/expected by CLRI/SETI */
+#define CLRI_STATUS_IE_BIT 4
+
+#define CLRI_STATUS_E_MASK 0xF
+#define CLRI_STATUS_IE_MASK (1 << CLRI_STATUS_IE_BIT)
+
#define AUX_USER_SP 0x00D
#define AUX_IRQ_CTRL 0x00E
#define AUX_IRQ_ACT 0x043 /* Active Intr across all levels */
@@ -100,6 +106,13 @@ static inline long arch_local_save_flags(void)
:
: "memory");
+ /* To be compatible with irq_save()/irq_restore()
+ * encode the irq bits as expected by CLRI/SETI
+ * (this was needed to make CONFIG_TRACE_IRQFLAGS work)
+ */
+ temp = (1 << 5) |
+ ((!!(temp & STATUS_IE_MASK)) << CLRI_STATUS_IE_BIT) |
+ (temp & CLRI_STATUS_E_MASK);
return temp;
}
@@ -108,7 +121,7 @@ static inline long arch_local_save_flags(void)
*/
static inline int arch_irqs_disabled_flags(unsigned long flags)
{
- return !(flags & (STATUS_IE_MASK));
+ return !(flags & CLRI_STATUS_IE_MASK);
}
static inline int arch_irqs_disabled(void)
@@ -128,11 +141,32 @@ static inline void arc_softirq_clear(int irq)
#else
+#ifdef CONFIG_TRACE_IRQFLAGS
+
+.macro TRACE_ASM_IRQ_DISABLE
+ bl trace_hardirqs_off
+.endm
+
+.macro TRACE_ASM_IRQ_ENABLE
+ bl trace_hardirqs_on
+.endm
+
+#else
+
+.macro TRACE_ASM_IRQ_DISABLE
+.endm
+
+.macro TRACE_ASM_IRQ_ENABLE
+.endm
+
+#endif
.macro IRQ_DISABLE scratch
clri
+ TRACE_ASM_IRQ_DISABLE
.endm
.macro IRQ_ENABLE scratch
+ TRACE_ASM_IRQ_ENABLE
seti
.endm
diff --git a/arch/arc/kernel/entry-arcv2.S b/arch/arc/kernel/entry-arcv2.S
index c1264607bbff3..7a1c124ff021d 100644
--- a/arch/arc/kernel/entry-arcv2.S
+++ b/arch/arc/kernel/entry-arcv2.S
@@ -69,8 +69,11 @@ ENTRY(handle_interrupt)
clri ; To make status32.IE agree with CPU internal state
- lr r0, [ICAUSE]
+#ifdef CONFIG_TRACE_IRQFLAGS
+ TRACE_ASM_IRQ_DISABLE
+#endif
+ lr r0, [ICAUSE]
mov blink, ret_from_exception
b.d arch_do_IRQ
@@ -169,6 +172,11 @@ END(EV_TLBProtV)
.Lrestore_regs:
+ # Interrpts are actually disabled from this point on, but will get
+ # reenabled after we return from interrupt/exception.
+ # But irq tracer needs to be told now...
+ TRACE_ASM_IRQ_ENABLE
+
ld r0, [sp, PT_status32] ; U/K mode at time of entry
lr r10, [AUX_IRQ_ACT]
diff --git a/arch/arc/kernel/entry-compact.S b/arch/arc/kernel/entry-compact.S
index 431433929189c..0cb0abaa0479e 100644
--- a/arch/arc/kernel/entry-compact.S
+++ b/arch/arc/kernel/entry-compact.S
@@ -341,6 +341,9 @@ END(call_do_page_fault)
.Lrestore_regs:
+ # Interrpts are actually disabled from this point on, but will get
+ # reenabled after we return from interrupt/exception.
+ # But irq tracer needs to be told now...
TRACE_ASM_IRQ_ENABLE
lr r10, [status32]
--
2.30.2