[PATCH v4 3/7] alpha: make irqflags helpers operate on IPL state

Alpha interrupt masking is controlled by the PAL IPL value, not by the
full processor status word.  Make arch_local_save_flags() return the
current IPL directly, and make arch_local_irq_restore() and
arch_irqs_disabled_flags() treat their argument as IPL state.

Mask the low IPL bits in the restore and test helpers so callers which
still pass a saved PS value continue to behave as expected.

This prepares the irqflags helpers for lockdep IRQ-state tracking, where
the saved flags value is used to determine whether hard IRQs are enabled
or disabled.

Reviewed-by: Matt Turner <[email protected]>
Tested-by: Matt Turner <[email protected]>
Signed-off-by: Magnus Lindholm <[email protected]>
---
 arch/alpha/include/asm/irqflags.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/alpha/include/asm/irqflags.h b/arch/alpha/include/asm/irqflags.h
index 9f25d4e0d37e..f207544f52de 100644
--- a/arch/alpha/include/asm/irqflags.h
+++ b/arch/alpha/include/asm/irqflags.h
@@ -26,7 +26,7 @@ extern int __min_ipl;
 
 static inline unsigned long arch_local_save_flags(void)
 {
-	return rdps();
+	return getipl();
 }
 
 static inline void arch_local_irq_disable(void)
@@ -51,13 +51,13 @@ static inline void arch_local_irq_enable(void)
 static inline void arch_local_irq_restore(unsigned long flags)
 {
 	barrier();
-	setipl(flags);
+	setipl(flags & 7);
 	barrier();
 }
 
 static inline bool arch_irqs_disabled_flags(unsigned long flags)
 {
-	return flags == IPL_MAX;
+	return (flags & 7) == IPL_MAX;
 }
 
 static inline bool arch_irqs_disabled(void)
-- 
2.53.0