ARM: SAMSUNG: Move IRQ VIC timer handling out to common header files

Move the VIC based timer interrupt handling out of plat-s3c64xx and
into plat-samsung to be re-used for other systems. This also reduces
the code size as we now have a common init routine and use the irq_desc
to store the interrupt number of the timer.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>

4 files changed, 108 insertions, 0 deletions

diff --git a/arch/arm/plat-samsung/Kconfig b/arch/arm/plat-samsung/Kconfig
index 9e7daf29b86a..cedecd87d899 100644
--- a/arch/arm/plat-samsung/Kconfig
+++ b/arch/arm/plat-samsung/Kconfig
@@ -19,6 +19,13 @@ config SAMSUNG_CLKSRC
 	  Select the clock code for the clksrc implementation
 	  used by newer systems such as the S3C64XX.
 
+# options for IRQ support
+
+config SAMSUNG_IRQ_VIC_TIMER
+       bool
+       help
+         Internal configuration to build the VIC timer interrupt code.
+
 # options for gpio configuration support
 
 config S3C_GPIO_CFG_S3C24XX
diff --git a/arch/arm/plat-samsung/Makefile b/arch/arm/plat-samsung/Makefile
index 2c0143713ea9..aa048c7337dd 100644
--- a/arch/arm/plat-samsung/Makefile
+++ b/arch/arm/plat-samsung/Makefile
@@ -17,6 +17,8 @@ obj-y				+= gpio-config.o
 
 obj-$(CONFIG_SAMSUNG_CLKSRC)	+= clock-clksrc.o
 
+obj-$(CONFIG_SAMSUNG_IRQ_VIC_TIMER) += irq-vic-timer.o
+
 # devices
 
 obj-$(CONFIG_S3C_DEV_HSMMC)	+= dev-hsmmc.o
diff --git a/arch/arm/plat-samsung/include/plat/irq-vic-timer.h b/arch/arm/plat-samsung/include/plat/irq-vic-timer.h
new file mode 100644
index 000000000000..a90b53431b5b
--- /dev/null
+++ b/arch/arm/plat-samsung/include/plat/irq-vic-timer.h
@@ -0,0 +1,13 @@
+/* arch/arm/plat-samsung/include/plat/irq-vic-timer.h
+ *
+ * Copyright (c) 2010 Simtec Electronics
+ *	Ben Dooks <ben@simtec.co.uk>
+ *
+ * Header file for Samsung SoC IRQ VIC timer
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+extern void s3c_init_vic_timer_irq(unsigned int vic, unsigned int timer);
diff --git a/arch/arm/plat-samsung/irq-vic-timer.c b/arch/arm/plat-samsung/irq-vic-timer.c
new file mode 100644
index 000000000000..0270519fcabc
--- /dev/null
+++ b/arch/arm/plat-samsung/irq-vic-timer.c
@@ -0,0 +1,86 @@
+/* arch/arm/plat-samsung/irq-vic-timer.c
+ *	originally part of arch/arm/plat-s3c64xx/irq.c
+ *
+ * Copyright 2008 Openmoko, Inc.
+ * Copyright 2008 Simtec Electronics
+ *      Ben Dooks <ben@simtec.co.uk>
+ *      http://armlinux.simtec.co.uk/
+ *
+ * S3C64XX - Interrupt handling
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+
+#include <mach/map.h>
+#include <plat/irq-vic-timer.h>
+#include <plat/regs-timer.h>
+
+static void s3c_irq_demux_vic_timer(unsigned int irq, struct irq_desc *desc)
+{
+	generic_handle_irq((int)desc->handler_data);
+}
+
+/* We assume the IRQ_TIMER0..IRQ_TIMER4 range is continuous. */
+
+static void s3c_irq_timer_mask(unsigned int irq)
+{
+	u32 reg = __raw_readl(S3C64XX_TINT_CSTAT);
+
+	reg &= 0x1f;  /* mask out pending interrupts */
+	reg &= ~(1 << (irq - IRQ_TIMER0));
+	__raw_writel(reg, S3C64XX_TINT_CSTAT);
+}
+
+static void s3c_irq_timer_unmask(unsigned int irq)
+{
+	u32 reg = __raw_readl(S3C64XX_TINT_CSTAT);
+
+	reg &= 0x1f;  /* mask out pending interrupts */
+	reg |= 1 << (irq - IRQ_TIMER0);
+	__raw_writel(reg, S3C64XX_TINT_CSTAT);
+}
+
+static void s3c_irq_timer_ack(unsigned int irq)
+{
+	u32 reg = __raw_readl(S3C64XX_TINT_CSTAT);
+
+	reg &= 0x1f;
+	reg |= (1 << 5) << (irq - IRQ_TIMER0);
+	__raw_writel(reg, S3C64XX_TINT_CSTAT);
+}
+
+static struct irq_chip s3c_irq_timer = {
+	.name		= "s3c-timer",
+	.mask		= s3c_irq_timer_mask,
+	.unmask		= s3c_irq_timer_unmask,
+	.ack		= s3c_irq_timer_ack,
+};
+
+/**
+ * s3c_init_vic_timer_irq() - initialise timer irq chanined off VIC.\
+ * @parent_irq: The parent IRQ on the VIC for the timer.
+ * @timer_irq: The IRQ to be used for the timer.
+ *
+ * Register the necessary IRQ chaining and support for the timer IRQs
+ * chained of the VIC.
+ */
+void __init s3c_init_vic_timer_irq(unsigned int parent_irq,
+				   unsigned int timer_irq)
+{
+	struct irq_desc *desc = irq_to_desc(parent_irq);
+
+	set_irq_chained_handler(parent_irq, s3c_irq_demux_vic_timer);
+
+	set_irq_chip(timer_irq, &s3c_irq_timer);
+	set_irq_handler(timer_irq, handle_level_irq);
+	set_irq_flags(timer_irq, IRQF_VALID);
+
+	desc->handler_data = (void *)timer_irq;
+}