1 files changed, 384 insertions, 0 deletions
diff --git a/arch/unicore32/kernel/irq.c b/arch/unicore32/kernel/irq.c
new file mode 100644
index 00000000000..2aa30a364bb
--- /dev/null
+++ b/arch/unicore32/kernel/irq.c
@@ -0,0 +1,384 @@
+/*
+ * linux/arch/unicore32/kernel/irq.c
+ *
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ * Copyright (C) 2001-2010 GUAN Xue-tao
+ *
+ * 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_stat.h>
+#include <linux/module.h>
+#include <linux/signal.h>
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/random.h>
+#include <linux/smp.h>
+#include <linux/init.h>
+#include <linux/seq_file.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+#include <linux/kallsyms.h>
+#include <linux/proc_fs.h>
+#include <linux/sysdev.h>
+#include <linux/gpio.h>
+
+#include <asm/system.h>
+#include <mach/hardware.h>
+
+#include "setup.h"
+
+/*
+ * PKUnity GPIO edge detection for IRQs:
+ * IRQs are generated on Falling-Edge, Rising-Edge, or both.
+ * Use this instead of directly setting GRER/GFER.
+ */
+static int GPIO_IRQ_rising_edge;
+static int GPIO_IRQ_falling_edge;
+static int GPIO_IRQ_mask = 0;
+
+#define GPIO_MASK(irq)		(1 << (irq - IRQ_GPIO0))
+
+static int puv3_gpio_type(struct irq_data *d, unsigned int type)
+{
+	unsigned int mask;
+
+	if (d->irq < IRQ_GPIOHIGH)
+		mask = 1 << d->irq;
+	else
+		mask = GPIO_MASK(d->irq);
+
+	if (type == IRQ_TYPE_PROBE) {
+		if ((GPIO_IRQ_rising_edge | GPIO_IRQ_falling_edge) & mask)
+			return 0;
+		type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
+	}
+
+	if (type & IRQ_TYPE_EDGE_RISING)
+		GPIO_IRQ_rising_edge |= mask;
+	else
+		GPIO_IRQ_rising_edge &= ~mask;
+	if (type & IRQ_TYPE_EDGE_FALLING)
+		GPIO_IRQ_falling_edge |= mask;
+	else
+		GPIO_IRQ_falling_edge &= ~mask;
+
+	writel(GPIO_IRQ_rising_edge & GPIO_IRQ_mask, GPIO_GRER);
+	writel(GPIO_IRQ_falling_edge & GPIO_IRQ_mask, GPIO_GFER);
+
+	return 0;
+}
+
+/*
+ * GPIO IRQs must be acknowledged.  This is for IRQs from 0 to 7.
+ */
+static void puv3_low_gpio_ack(struct irq_data *d)
+{
+	writel((1 << d->irq), GPIO_GEDR);
+}
+
+static void puv3_low_gpio_mask(struct irq_data *d)
+{
+	writel(readl(INTC_ICMR) & ~(1 << d->irq), INTC_ICMR);
+}
+
+static void puv3_low_gpio_unmask(struct irq_data *d)
+{
+	writel(readl(INTC_ICMR) | (1 << d->irq), INTC_ICMR);
+}
+
+static int puv3_low_gpio_wake(struct irq_data *d, unsigned int on)
+{
+	if (on)
+		writel(readl(PM_PWER) | (1 << d->irq), PM_PWER);
+	else
+		writel(readl(PM_PWER) & ~(1 << d->irq), PM_PWER);
+	return 0;
+}
+
+static struct irq_chip puv3_low_gpio_chip = {
+	.name		= "GPIO-low",
+	.irq_ack	= puv3_low_gpio_ack,
+	.irq_mask	= puv3_low_gpio_mask,
+	.irq_unmask	= puv3_low_gpio_unmask,
+	.irq_set_type	= puv3_gpio_type,
+	.irq_set_wake	= puv3_low_gpio_wake,
+};
+
+/*
+ * IRQ8 (GPIO0 through 27) handler.  We enter here with the
+ * irq_controller_lock held, and IRQs disabled.  Decode the IRQ
+ * and call the handler.
+ */
+static void
+puv3_gpio_handler(unsigned int irq, struct irq_desc *desc)
+{
+	unsigned int mask;
+
+	mask = readl(GPIO_GEDR);
+	do {
+		/*
+		 * clear down all currently active IRQ sources.
+		 * We will be processing them all.
+		 */
+		writel(mask, GPIO_GEDR);
+
+		irq = IRQ_GPIO0;
+		do {
+			if (mask & 1)
+				generic_handle_irq(irq);
+			mask >>= 1;
+			irq++;
+		} while (mask);
+		mask = readl(GPIO_GEDR);
+	} while (mask);
+}
+
+/*
+ * GPIO0-27 edge IRQs need to be handled specially.
+ * In addition, the IRQs are all collected up into one bit in the
+ * interrupt controller registers.
+ */
+static void puv3_high_gpio_ack(struct irq_data *d)
+{
+	unsigned int mask = GPIO_MASK(d->irq);
+
+	writel(mask, GPIO_GEDR);
+}
+
+static void puv3_high_gpio_mask(struct irq_data *d)
+{
+	unsigned int mask = GPIO_MASK(d->irq);
+
+	GPIO_IRQ_mask &= ~mask;
+
+	writel(readl(GPIO_GRER) & ~mask, GPIO_GRER);
+	writel(readl(GPIO_GFER) & ~mask, GPIO_GFER);
+}
+
+static void puv3_high_gpio_unmask(struct irq_data *d)
+{
+	unsigned int mask = GPIO_MASK(d->irq);
+
+	GPIO_IRQ_mask |= mask;
+
+	writel(GPIO_IRQ_rising_edge & GPIO_IRQ_mask, GPIO_GRER);
+	writel(GPIO_IRQ_falling_edge & GPIO_IRQ_mask, GPIO_GFER);
+}
+
+static int puv3_high_gpio_wake(struct irq_data *d, unsigned int on)
+{
+	if (on)
+		writel(readl(PM_PWER) | PM_PWER_GPIOHIGH, PM_PWER);
+	else
+		writel(readl(PM_PWER) & ~PM_PWER_GPIOHIGH, PM_PWER);
+	return 0;
+}
+
+static struct irq_chip puv3_high_gpio_chip = {
+	.name		= "GPIO-high",
+	.irq_ack	= puv3_high_gpio_ack,
+	.irq_mask	= puv3_high_gpio_mask,
+	.irq_unmask	= puv3_high_gpio_unmask,
+	.irq_set_type	= puv3_gpio_type,
+	.irq_set_wake	= puv3_high_gpio_wake,
+};
+
+/*
+ * We don't need to ACK IRQs on the PKUnity unless they're GPIOs
+ * this is for internal IRQs i.e. from 8 to 31.
+ */
+static void puv3_mask_irq(struct irq_data *d)
+{
+	writel(readl(INTC_ICMR) & ~(1 << d->irq), INTC_ICMR);
+}
+
+static void puv3_unmask_irq(struct irq_data *d)
+{
+	writel(readl(INTC_ICMR) | (1 << d->irq), INTC_ICMR);
+}
+
+/*
+ * Apart form GPIOs, only the RTC alarm can be a wakeup event.
+ */
+static int puv3_set_wake(struct irq_data *d, unsigned int on)
+{
+	if (d->irq == IRQ_RTCAlarm) {
+		if (on)
+			writel(readl(PM_PWER) | PM_PWER_RTC, PM_PWER);
+		else
+			writel(readl(PM_PWER) & ~PM_PWER_RTC, PM_PWER);
+		return 0;
+	}
+	return -EINVAL;
+}
+
+static struct irq_chip puv3_normal_chip = {
+	.name		= "PKUnity-v3",
+	.irq_ack	= puv3_mask_irq,
+	.irq_mask	= puv3_mask_irq,
+	.irq_unmask	= puv3_unmask_irq,
+	.irq_set_wake	= puv3_set_wake,
+};
+
+static struct resource irq_resource = {
+	.name	= "irqs",
+	.start	= io_v2p(PKUNITY_INTC_BASE),
+	.end	= io_v2p(PKUNITY_INTC_BASE) + 0xFFFFF,
+};
+
+static struct puv3_irq_state {
+	unsigned int	saved;
+	unsigned int	icmr;
+	unsigned int	iclr;
+	unsigned int	iccr;
+} puv3_irq_state;
+
+static int puv3_irq_suspend(struct sys_device *dev, pm_message_t state)
+{
+	struct puv3_irq_state *st = &puv3_irq_state;
+
+	st->saved = 1;
+	st->icmr = readl(INTC_ICMR);
+	st->iclr = readl(INTC_ICLR);
+	st->iccr = readl(INTC_ICCR);
+
+	/*
+	 * Disable all GPIO-based interrupts.
+	 */
+	writel(readl(INTC_ICMR) & ~(0x1ff), INTC_ICMR);
+
+	/*
+	 * Set the appropriate edges for wakeup.
+	 */
+	writel(readl(PM_PWER) & GPIO_IRQ_rising_edge, GPIO_GRER);
+	writel(readl(PM_PWER) & GPIO_IRQ_falling_edge, GPIO_GFER);
+
+	/*
+	 * Clear any pending GPIO interrupts.
+	 */
+	writel(readl(GPIO_GEDR), GPIO_GEDR);
+
+	return 0;
+}
+
+static int puv3_irq_resume(struct sys_device *dev)
+{
+	struct puv3_irq_state *st = &puv3_irq_state;
+
+	if (st->saved) {
+		writel(st->iccr, INTC_ICCR);
+		writel(st->iclr, INTC_ICLR);
+
+		writel(GPIO_IRQ_rising_edge & GPIO_IRQ_mask, GPIO_GRER);
+		writel(GPIO_IRQ_falling_edge & GPIO_IRQ_mask, GPIO_GFER);
+
+		writel(st->icmr, INTC_ICMR);
+	}
+	return 0;
+}
+
+static struct sysdev_class puv3_irq_sysclass = {
+	.name		= "pkunity-irq",
+	.suspend	= puv3_irq_suspend,
+	.resume		= puv3_irq_resume,
+};
+
+static struct sys_device puv3_irq_device = {
+	.id		= 0,
+	.cls		= &puv3_irq_sysclass,
+};
+
+static int __init puv3_irq_init_devicefs(void)
+{
+	sysdev_class_register(&puv3_irq_sysclass);
+	return sysdev_register(&puv3_irq_device);
+}
+
+device_initcall(puv3_irq_init_devicefs);
+
+void __init init_IRQ(void)
+{
+	unsigned int irq;
+
+	request_resource(&iomem_resource, &irq_resource);
+
+	/* disable all IRQs */
+	writel(0, INTC_ICMR);
+
+	/* all IRQs are IRQ, not REAL */
+	writel(0, INTC_ICLR);
+
+	/* clear all GPIO edge detects */
+	writel(FMASK(8, 0) & ~FIELD(1, 1, GPI_SOFF_REQ), GPIO_GPIR);
+	writel(0, GPIO_GFER);
+	writel(0, GPIO_GRER);
+	writel(0x0FFFFFFF, GPIO_GEDR);
+
+	writel(1, INTC_ICCR);
+
+	for (irq = 0; irq < IRQ_GPIOHIGH; irq++) {
+		irq_set_chip(irq, &puv3_low_gpio_chip);
+		irq_set_handler(irq, handle_edge_irq);
+		irq_modify_status(irq,
+			IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN,
+			0);
+	}
+
+	for (irq = IRQ_GPIOHIGH + 1; irq < IRQ_GPIO0; irq++) {
+		irq_set_chip(irq, &puv3_normal_chip);
+		irq_set_handler(irq, handle_level_irq);
+		irq_modify_status(irq,
+			IRQ_NOREQUEST | IRQ_NOAUTOEN,
+			IRQ_NOPROBE);
+	}
+
+	for (irq = IRQ_GPIO0; irq <= IRQ_GPIO27; irq++) {
+		irq_set_chip(irq, &puv3_high_gpio_chip);
+		irq_set_handler(irq, handle_edge_irq);
+		irq_modify_status(irq,
+			IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN,
+			0);
+	}
+
+	/*
+	 * Install handler for GPIO 0-27 edge detect interrupts
+	 */
+	irq_set_chip(IRQ_GPIOHIGH, &puv3_normal_chip);
+	irq_set_chained_handler(IRQ_GPIOHIGH, puv3_gpio_handler);
+
+#ifdef CONFIG_PUV3_GPIO
+	puv3_init_gpio();
+#endif
+}
+
+/*
+ * do_IRQ handles all hardware IRQ's.  Decoded IRQs should not
+ * come via this function.  Instead, they should provide their
+ * own 'handler'
+ */
+asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs)
+{
+	struct pt_regs *old_regs = set_irq_regs(regs);
+
+	irq_enter();
+
+	/*
+	 * Some hardware gives randomly wrong interrupts.  Rather
+	 * than crashing, do something sensible.
+	 */
+	if (unlikely(irq >= nr_irqs)) {
+		if (printk_ratelimit())
+			printk(KERN_WARNING "Bad IRQ%u\n", irq);
+		ack_bad_irq(irq);
+	} else {
+		generic_handle_irq(irq);
+	}
+
+	irq_exit();
+	set_irq_regs(old_regs);
+}
+