From 1ed763b8887616fbac8532895b764daf4d5d4f25 Mon Sep 17 00:00:00 2001
From: Florian Fainelli <florian@openwrt.org>
Date: Thu, 6 Dec 2012 22:40:02 +0000
Subject: [PATCH] cleanup and make interrupt code more robust

Signed-off-by: Florian Fainelli <florian@openwrt.org>

SVN-Revision: 34552
---
 .../adm8668/files/arch/mips/adm8668/irq.c     | 47 +++++++++++++++----
 .../mips/include/asm/mach-adm8668/adm8668.h   |  7 ---
 .../arch/mips/include/asm/mach-adm8668/irq.h  |  4 +-
 3 files changed, 39 insertions(+), 19 deletions(-)

diff --git a/target/linux/adm8668/files/arch/mips/adm8668/irq.c b/target/linux/adm8668/files/arch/mips/adm8668/irq.c
index 9fa9e675e491..62b7d2dc3252 100644
--- a/target/linux/adm8668/files/arch/mips/adm8668/irq.c
+++ b/target/linux/adm8668/files/arch/mips/adm8668/irq.c
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2010 Scott Nicholas <neutronscott@scottn.us>
+ * Copyright (C) 2012 Florian Fainelli <florian@openwrt.org>
  *
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
@@ -20,15 +21,38 @@
 #include <asm/irq.h>
 #include <adm8668.h>
 
+/* interrupt controller */
+#define IRQ_STATUS_REG		0x00	/* Read */
+#define IRQ_ENABLE_REG		0x08	/* Read/Write */
+#define IRQ_DISABLE_REG		0x0C	/* Write */
+
+#define IRQ_MASK		0xffff
+
+static inline void intc_write_reg(u32 val, unsigned int reg)
+{
+	void __iomem *base = (void __iomem *)KSEG1ADDR(ADM8668_INTC_BASE);
+
+	__raw_writel(val, base + reg);
+}
+
+static inline u32 intc_read_reg(unsigned int reg)
+{
+	void __iomem *base = (void __iomem *)KSEG1ADDR(ADM8668_INTC_BASE);
+
+	return __raw_readl(base + reg);
+}
+
 static void adm8668_irq_cascade(void)
 {
-	int i;
-	unsigned long intsrc;
+	int irq;
+	u32 intsrc;
 
-	intsrc = ADM8668_INTC_REG(IRQ_STATUS_REG) & IRQ_MASK;
-	for (i = 0; intsrc; intsrc >>= 1, i++)
-		if (intsrc & 0x1)
-			do_IRQ(i);
+	intsrc = intc_read_reg(IRQ_STATUS_REG) & IRQ_MASK;
+	if (intsrc) {
+		irq = fls(intsrc) - 1;
+		do_IRQ(irq);
+	} else
+		spurious_interrupt();
 }
 
 /*
@@ -43,8 +67,10 @@ void plat_irq_dispatch(void)
 	/* timer interrupt, that we renumbered */
 	if (pending & STATUSF_IP7)
 		do_IRQ(MIPS_CPU_IRQ_BASE + 7);
-	if (pending & STATUSF_IP2)
+	else if (pending & STATUSF_IP2)
 		adm8668_irq_cascade();
+	else
+		spurious_interrupt();
 }
 
 /*
@@ -52,13 +78,13 @@ void plat_irq_dispatch(void)
  */
 static void enable_adm8668_irq(struct irq_data *d)
 {
-	ADM8668_INTC_REG(IRQ_ENABLE_REG) = (1 << d->irq);
+	intc_write_reg((1 << d->irq), IRQ_ENABLE_REG);
 }
 
 
 static void ack_adm8668_irq(struct irq_data *d)
 {
-	ADM8668_INTC_REG(IRQ_DISABLE_REG) = (1 << d->irq);
+	intc_write_reg((1 << d->irq), IRQ_DISABLE_REG);
 }
 
 /*
@@ -79,6 +105,9 @@ static void __init init_adm8668_irqs(void)
 {
 	int i;
 
+	/* disable all interrupts for the moment */
+	intc_write_reg(IRQ_MASK, IRQ_DISABLE_REG);
+
 	for (i = 0; i <= INT_LVL_MAX; i++)
 		irq_set_chip_and_handler(i, &adm8668_irq_type,
 			handle_level_irq);
diff --git a/target/linux/adm8668/files/arch/mips/include/asm/mach-adm8668/adm8668.h b/target/linux/adm8668/files/arch/mips/include/asm/mach-adm8668/adm8668.h
index bb4466c522ad..250447bbf357 100644
--- a/target/linux/adm8668/files/arch/mips/include/asm/mach-adm8668/adm8668.h
+++ b/target/linux/adm8668/files/arch/mips/include/asm/mach-adm8668/adm8668.h
@@ -32,11 +32,6 @@
 /** onboard uart **/
 #define ADM8668_UARTCLK_FREQ	62500000
 
-/* interrupt controller */
-#define IRQ_STATUS_REG		0x00	/* Read */
-#define IRQ_ENABLE_REG		0x08	/* Read/Write */
-#define IRQ_DISABLE_REG		0x0C	/* Write */
-
 /* interrupt levels */
 #define INT_LVL_SWI		1
 #define INT_LVL_COMMS_RX	2
@@ -56,8 +51,6 @@
 #define INT_LVL_MAX		INT_LVL_USB
 
 /* register access macros */
-#define ADM8668_INTC_REG(_reg)	\
-	(*((volatile unsigned long *)(KSEG1ADDR(ADM8668_INTC_BASE + (_reg)))))
 #define ADM8668_LAN_REG(_reg)		\
 	(*((volatile unsigned int *)(KSEG1ADDR(ADM8668_LAN_BASE + (_reg)))))
 #define ADM8668_WAN_REG(_reg)		\
diff --git a/target/linux/adm8668/files/arch/mips/include/asm/mach-adm8668/irq.h b/target/linux/adm8668/files/arch/mips/include/asm/mach-adm8668/irq.h
index 1341309f2bb0..ea859f03af4e 100644
--- a/target/linux/adm8668/files/arch/mips/include/asm/mach-adm8668/irq.h
+++ b/target/linux/adm8668/files/arch/mips/include/asm/mach-adm8668/irq.h
@@ -8,9 +8,7 @@
 #ifndef __ASM_MACH_ADM8668_IRQ_H
 #define __ASM_MACH_ADM8668_IRQ_H
 
-#define	NR_IRQS	32
+#define	NR_IRQS			32
 #define	MIPS_CPU_IRQ_BASE	16
 
-#define IRQ_MASK		0xffff
-
 #endif /* __ASM_MACH_ADM8668_IRQ_H */
-- 
2.30.2