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-rw-r--r--arch/arm/plat-s3c64xx/irq.c257
1 files changed, 257 insertions, 0 deletions
diff --git a/arch/arm/plat-s3c64xx/irq.c b/arch/arm/plat-s3c64xx/irq.c
new file mode 100644
index 0000000..a94f1d5
--- /dev/null
+++ b/arch/arm/plat-s3c64xx/irq.c
@@ -0,0 +1,257 @@
+/* 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 <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 = S3C_VA_UART0,
+ .base_irq = IRQ_S3CUART_BASE0,
+ .parent_irq = IRQ_UART0,
+ },
+ [1] = {
+ .regs = S3C_VA_UART1,
+ .base_irq = IRQ_S3CUART_BASE1,
+ .parent_irq = IRQ_UART1,
+ },
+ [2] = {
+ .regs = S3C_VA_UART2,
+ .base_irq = IRQ_S3CUART_BASE2,
+ .parent_irq = IRQ_UART2,
+ },
+ [3] = {
+ .regs = 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 s3c64xx_uart_irq(struct uart_irq *uirq)
+{
+ void *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 s3c64xx_init_irq(u32 vic0_valid, u32 vic1_valid)
+{
+ int uart, irq;
+
+ printk(KERN_DEBUG "%s: initialising interrupts\n", __func__);
+
+ /* initialise the pair of VICs */
+ vic_init(S3C_VA_VIC0, S3C_VIC0_BASE, vic0_valid);
+ vic_init(S3C_VA_VIC1, S3C_VIC1_BASE, vic1_valid);
+
+ /* add the timer sub-irqs */
+
+ set_irq_chained_handler(IRQ_TIMER0_VIC, s3c_irq_demux_timer0);
+ set_irq_chained_handler(IRQ_TIMER1_VIC, s3c_irq_demux_timer1);
+ set_irq_chained_handler(IRQ_TIMER2_VIC, s3c_irq_demux_timer2);
+ set_irq_chained_handler(IRQ_TIMER3_VIC, s3c_irq_demux_timer3);
+ set_irq_chained_handler(IRQ_TIMER4_VIC, 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++)
+ s3c64xx_uart_irq(&uart_irqs[uart]);
+}
+
+
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