From 5ee2eceb0750ebedace1bd04c1efa6a325038f2a Mon Sep 17 00:00:00 2001 From: Thomas Bogendoerfer Date: Wed, 16 Sep 2020 15:54:37 +0200 Subject: [PATCH] MIPS: SNI: Fix spurious interrupts [ Upstream commit b959b97860d0fee8c8f6a3e641d3c2ad76eab6be ] On A20R machines the interrupt pending bits in cause register need to be updated by requesting the chipset to do it. This needs to be done to find the interrupt cause and after interrupt service. In commit 0b888c7f3a03 ("MIPS: SNI: Convert to new irq_chip functions") the function to do after service update got lost, which caused spurious interrupts. Fixes: 0b888c7f3a03 ("MIPS: SNI: Convert to new irq_chip functions") Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin --- arch/mips/sni/a20r.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/arch/mips/sni/a20r.c b/arch/mips/sni/a20r.c index f9407e170476..c6af7047eb0d 100644 --- a/arch/mips/sni/a20r.c +++ b/arch/mips/sni/a20r.c @@ -143,7 +143,10 @@ static struct platform_device sc26xx_pdev = { }, }; -static u32 a20r_ack_hwint(void) +/* + * Trigger chipset to update CPU's CAUSE IP field + */ +static u32 a20r_update_cause_ip(void) { u32 status = read_c0_status(); @@ -205,12 +208,14 @@ static void a20r_hwint(void) int irq; clear_c0_status(IE_IRQ0); - status = a20r_ack_hwint(); + status = a20r_update_cause_ip(); cause = read_c0_cause(); irq = ffs(((cause & status) >> 8) & 0xf8); if (likely(irq > 0)) do_IRQ(SNI_A20R_IRQ_BASE + irq - 1); + + a20r_update_cause_ip(); set_c0_status(IE_IRQ0); }