linux-kernel - [PATCH V5 3/3] irqchip/irq-csky-mpintc: Remove unnecessary loop in interrupt handler

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Date:   Thu,  6 Jun 2019 15:37:33 +0800
From:   guoren@...nel.org
To:     marc.zyngier@....com, mark.rutland@....com, tglx@...utronix.de
Cc:     linux-kernel@...r.kernel.org, jason@...edaemon.net,
        guoren@...nel.org, linux-csky@...r.kernel.org,
        Guo Ren <ren_guo@...ky.com>
Subject: [PATCH V5 3/3] irqchip/irq-csky-mpintc: Remove unnecessary loop in interrupt handler

From: Guo Ren <ren_guo@...ky.com>

csky_mpintc_handler()
  ->handle_domain_irq()
    ->irq_exit()
      ->invoke_softirq()
        ->__do_softirq()
          ->local_irq_enable()

If new interrupt coming, it'll get into interrupt trap before return to
csky_mpintc_handler(). So there is no need loop in csky_mpintc_handler.

Signed-off-by: Guo Ren <ren_guo@...ky.com>
Cc: Marc Zyngier <marc.zyngier@....com>
---
 drivers/irqchip/irq-csky-mpintc.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/irqchip/irq-csky-mpintc.c b/drivers/irqchip/irq-csky-mpintc.c
index 4457722..806ba0e 100644
--- a/drivers/irqchip/irq-csky-mpintc.c
+++ b/drivers/irqchip/irq-csky-mpintc.c
@@ -34,7 +34,6 @@ static void __iomem *INTCL_base;
 #define INTCL_PICTLR	0x0
 #define INTCL_CFGR	0x14
 #define INTCL_SIGR	0x60
-#define INTCL_HPPIR	0x68
 #define INTCL_RDYIR	0x6c
 #define INTCL_SENR	0xa0
 #define INTCL_CENR	0xa4
@@ -75,11 +74,8 @@ static void csky_mpintc_handler(struct pt_regs *regs)
 {
 	void __iomem *reg_base = this_cpu_read(intcl_reg);
 
-	do {
-		handle_domain_irq(root_domain,
-				  readl_relaxed(reg_base + INTCL_RDYIR),
-				  regs);
-	} while (readl_relaxed(reg_base + INTCL_HPPIR) & BIT(31));
+	handle_domain_irq(root_domain,
+		readl_relaxed(reg_base + INTCL_RDYIR), regs);
 }
 
 static void csky_mpintc_enable(struct irq_data *d)
-- 
2.7.4