ARM: S5PC100: IRQ and timer

S5PC100 has 3 VICs(Vectored Interrupt Controller). The VICs come from S3C64xx
series, so the driver source code can be shared with S3C families. The S5PC100
has 3 VICs while S3C64xx has only 2.

Signed-off-by: Byungho Min <bhmin@samsung.com>
[ben-linux@fluff.org: subject fixup]
Signed-off-by: Ben Dooks <ben-linux@fluff.org>

1 files changed, 259 insertions, 0 deletions

diff --git a/arch/arm/plat-s5pc1xx/irq.c b/arch/arm/plat-s5pc1xx/irq.c
new file mode 100644
index 000000000000..80d6dd942cb8
--- /dev/null
+++ b/arch/arm/plat-s5pc1xx/irq.c
@@ -0,0 +1,259 @@
+/* arch/arm/plat-s5pc1xx/irq.c
+ *
+ * Copyright 2009 Samsung Electronics Co.
+ *      Byungho Min <bhmin@samsung.com>
+ *
+ * S5PC1XX - Interrupt handling
+ *
+ * Based on plat-s3c64xx/irq.c
+ *
+ * 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 <asm/hardware/vic.h>
+
+#include <mach/map.h>
+#include <plat/regs-timer.h>
+#include <plat/cpu.h>
+
+/* Timer interrupt handling */
+
+static void s3c_irq_demux_timer(unsigned int base_irq, unsigned int sub_irq)
+{
+	generic_handle_irq(sub_irq);
+}
+
+static void s3c_irq_demux_timer0(unsigned int irq, struct irq_desc *desc)
+{
+	s3c_irq_demux_timer(irq, IRQ_TIMER0);
+}
+
+static void s3c_irq_demux_timer1(unsigned int irq, struct irq_desc *desc)
+{
+	s3c_irq_demux_timer(irq, IRQ_TIMER1);
+}
+
+static void s3c_irq_demux_timer2(unsigned int irq, struct irq_desc *desc)
+{
+	s3c_irq_demux_timer(irq, IRQ_TIMER2);
+}
+
+static void s3c_irq_demux_timer3(unsigned int irq, struct irq_desc *desc)
+{
+	s3c_irq_demux_timer(irq, IRQ_TIMER3);
+}
+
+static void s3c_irq_demux_timer4(unsigned int irq, struct irq_desc *desc)
+{
+	s3c_irq_demux_timer(irq, IRQ_TIMER4);
+}
+
+/* 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,
+};
+
+struct uart_irq {
+	void __iomem	*regs;
+	unsigned int	 base_irq;
+	unsigned int	 parent_irq;
+};
+
+/* Note, we make use of the fact that the parent IRQs, IRQ_UART[0..3]
+ * are consecutive when looking up the interrupt in the demux routines.
+ */
+static struct uart_irq uart_irqs[] = {
+	[0] = {
+		.regs		= (void *)S3C_VA_UART0,
+		.base_irq	= IRQ_S3CUART_BASE0,
+		.parent_irq	= IRQ_UART0,
+	},
+	[1] = {
+		.regs		= (void *)S3C_VA_UART1,
+		.base_irq	= IRQ_S3CUART_BASE1,
+		.parent_irq	= IRQ_UART1,
+	},
+	[2] = {
+		.regs		= (void *)S3C_VA_UART2,
+		.base_irq	= IRQ_S3CUART_BASE2,
+		.parent_irq	= IRQ_UART2,
+	},
+	[3] = {
+		.regs		= (void *)S3C_VA_UART3,
+		.base_irq	= IRQ_S3CUART_BASE3,
+		.parent_irq	= IRQ_UART3,
+	},
+};
+
+static inline void __iomem *s3c_irq_uart_base(unsigned int irq)
+{
+	struct uart_irq *uirq = get_irq_chip_data(irq);
+	return uirq->regs;
+}
+
+static inline unsigned int s3c_irq_uart_bit(unsigned int irq)
+{
+	return irq & 3;
+}
+
+/* UART interrupt registers, not worth adding to seperate include header */
+#define S3C64XX_UINTP	0x30
+#define S3C64XX_UINTSP	0x34
+#define S3C64XX_UINTM	0x38
+
+static void s3c_irq_uart_mask(unsigned int irq)
+{
+	void __iomem *regs = s3c_irq_uart_base(irq);
+	unsigned int bit = s3c_irq_uart_bit(irq);
+	u32 reg;
+
+	reg = __raw_readl(regs + S3C64XX_UINTM);
+	reg |= (1 << bit);
+	__raw_writel(reg, regs + S3C64XX_UINTM);
+}
+
+static void s3c_irq_uart_maskack(unsigned int irq)
+{
+	void __iomem *regs = s3c_irq_uart_base(irq);
+	unsigned int bit = s3c_irq_uart_bit(irq);
+	u32 reg;
+
+	reg = __raw_readl(regs + S3C64XX_UINTM);
+	reg |= (1 << bit);
+	__raw_writel(reg, regs + S3C64XX_UINTM);
+	__raw_writel(1 << bit, regs + S3C64XX_UINTP);
+}
+
+static void s3c_irq_uart_unmask(unsigned int irq)
+{
+	void __iomem *regs = s3c_irq_uart_base(irq);
+	unsigned int bit = s3c_irq_uart_bit(irq);
+	u32 reg;
+
+	reg = __raw_readl(regs + S3C64XX_UINTM);
+	reg &= ~(1 << bit);
+	__raw_writel(reg, regs + S3C64XX_UINTM);
+}
+
+static void s3c_irq_uart_ack(unsigned int irq)
+{
+	void __iomem *regs = s3c_irq_uart_base(irq);
+	unsigned int bit = s3c_irq_uart_bit(irq);
+
+	__raw_writel(1 << bit, regs + S3C64XX_UINTP);
+}
+
+static void s3c_irq_demux_uart(unsigned int irq, struct irq_desc *desc)
+{
+	struct uart_irq *uirq = &uart_irqs[irq - IRQ_UART0];
+	u32 pend = __raw_readl(uirq->regs + S3C64XX_UINTP);
+	int base = uirq->base_irq;
+
+	if (pend & (1 << 0))
+		generic_handle_irq(base);
+	if (pend & (1 << 1))
+		generic_handle_irq(base + 1);
+	if (pend & (1 << 2))
+		generic_handle_irq(base + 2);
+	if (pend & (1 << 3))
+		generic_handle_irq(base + 3);
+}
+
+static struct irq_chip s3c_irq_uart = {
+	.name		= "s3c-uart",
+	.mask		= s3c_irq_uart_mask,
+	.unmask		= s3c_irq_uart_unmask,
+	.mask_ack	= s3c_irq_uart_maskack,
+	.ack		= s3c_irq_uart_ack,
+};
+
+static void __init s5pc1xx_uart_irq(struct uart_irq *uirq)
+{
+	void __iomem *reg_base = uirq->regs;
+	unsigned int irq;
+	int offs;
+
+	/* mask all interrupts at the start. */
+	__raw_writel(0xf, reg_base + S3C64XX_UINTM);
+
+	for (offs = 0; offs < 3; offs++) {
+		irq = uirq->base_irq + offs;
+
+		set_irq_chip(irq, &s3c_irq_uart);
+		set_irq_chip_data(irq, uirq);
+		set_irq_handler(irq, handle_level_irq);
+		set_irq_flags(irq, IRQF_VALID);
+	}
+
+	set_irq_chained_handler(uirq->parent_irq, s3c_irq_demux_uart);
+}
+
+void __init s5pc1xx_init_irq(u32 *vic_valid, int num)
+{
+	int i;
+	int uart, irq;
+
+	printk(KERN_DEBUG "%s: initialising interrupts\n", __func__);
+
+	/* initialise the pair of VICs */
+	for (i = 0; i < num; i++)
+		vic_init((void *)S5PC1XX_VA_VIC(i), S3C_IRQ(i * S3C_IRQ_OFFSET),
+				vic_valid[i], 0);
+
+	/* add the timer sub-irqs */
+
+	set_irq_chained_handler(IRQ_TIMER0, s3c_irq_demux_timer0);
+	set_irq_chained_handler(IRQ_TIMER1, s3c_irq_demux_timer1);
+	set_irq_chained_handler(IRQ_TIMER2, s3c_irq_demux_timer2);
+	set_irq_chained_handler(IRQ_TIMER3, s3c_irq_demux_timer3);
+	set_irq_chained_handler(IRQ_TIMER4, s3c_irq_demux_timer4);
+
+	for (irq = IRQ_TIMER0; irq <= IRQ_TIMER4; irq++) {
+		set_irq_chip(irq, &s3c_irq_timer);
+		set_irq_handler(irq, handle_level_irq);
+		set_irq_flags(irq, IRQF_VALID);
+	}
+
+	for (uart = 0; uart < ARRAY_SIZE(uart_irqs); uart++)
+		s5pc1xx_uart_irq(&uart_irqs[uart]);
+}
+
+