[PATCH] riscv: Fix local irq restore when flags indicates irq disabled

[Xu Lu]

When arch_local_irq_restore() is called with flags indicating irqs
disabled, we need to clear SR_IE bit in CSR_STATUS, whereas current
implementation based on csr_set() function only sets SR_IE bit of
CSR_STATUS when SR_IE bit of flags is high and does nothing when
SR_IE bit of flags is low.

This commit supplies csr clear operation when calling irq restore
function with flags indicating irq disabled.

Fixes: 6d60b6ee0c97 ("RISC-V: Device, timer, IRQs, and the SBI")
Signed-off-by: Xu Lu <luxu.kernel at bytedance.com>
---
 arch/riscv/include/asm/irqflags.h | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/include/asm/irqflags.h b/arch/riscv/include/asm/irqflags.h
index 6fd8cbfcfcc7..f3aad7bfadb7 100644
--- a/arch/riscv/include/asm/irqflags.h
+++ b/arch/riscv/include/asm/irqflags.h
@@ -48,7 +48,10 @@ static inline int arch_irqs_disabled(void)
 /* set interrupt enabled status */
 static inline void arch_local_irq_restore(unsigned long flags)
 {
-	csr_set(CSR_STATUS, flags & SR_IE);
+	if (flags & SR_IE)
+		csr_set(CSR_STATUS, SR_IE);
+	else
+		csr_clear(CSR_STATUS, SR_IE);
 }
 
 #endif /* _ASM_RISCV_IRQFLAGS_H */
-- 
2.20.1