From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001
From: André Fabian Silva Delgado <emulatorman@parabola.nu>
Date: Wed, 5 Aug 2015 17:04:01 -0300
Subject: Initial import

---
 arch/arm/mach-sa1100/irq.c | 178 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 178 insertions(+)
 create mode 100644 arch/arm/mach-sa1100/irq.c

(limited to 'arch/arm/mach-sa1100/irq.c')

diff --git a/arch/arm/mach-sa1100/irq.c b/arch/arm/mach-sa1100/irq.c
new file mode 100644
index 000000000..65aebfa66
--- /dev/null
+++ b/arch/arm/mach-sa1100/irq.c
@@ -0,0 +1,178 @@
+/*
+ * linux/arch/arm/mach-sa1100/irq.c
+ *
+ * Copyright (C) 1999-2001 Nicolas Pitre
+ *
+ * Generic IRQ handling for the SA11x0, GPIO 11-27 IRQ demultiplexing.
+ *
+ * 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/init.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/ioport.h>
+#include <linux/syscore_ops.h>
+
+#include <mach/hardware.h>
+#include <mach/irqs.h>
+#include <asm/mach/irq.h>
+#include <asm/exception.h>
+
+#include "generic.h"
+
+
+/*
+ * We don't need to ACK IRQs on the SA1100 unless they're GPIOs
+ * this is for internal IRQs i.e. from IRQ LCD to RTCAlrm.
+ */
+static void sa1100_mask_irq(struct irq_data *d)
+{
+	ICMR &= ~BIT(d->hwirq);
+}
+
+static void sa1100_unmask_irq(struct irq_data *d)
+{
+	ICMR |= BIT(d->hwirq);
+}
+
+/*
+ * Apart form GPIOs, only the RTC alarm can be a wakeup event.
+ */
+static int sa1100_set_wake(struct irq_data *d, unsigned int on)
+{
+	if (BIT(d->hwirq) == IC_RTCAlrm) {
+		if (on)
+			PWER |= PWER_RTC;
+		else
+			PWER &= ~PWER_RTC;
+		return 0;
+	}
+	return -EINVAL;
+}
+
+static struct irq_chip sa1100_normal_chip = {
+	.name		= "SC",
+	.irq_ack	= sa1100_mask_irq,
+	.irq_mask	= sa1100_mask_irq,
+	.irq_unmask	= sa1100_unmask_irq,
+	.irq_set_wake	= sa1100_set_wake,
+};
+
+static int sa1100_normal_irqdomain_map(struct irq_domain *d,
+		unsigned int irq, irq_hw_number_t hwirq)
+{
+	irq_set_chip_and_handler(irq, &sa1100_normal_chip,
+				 handle_level_irq);
+	set_irq_flags(irq, IRQF_VALID);
+
+	return 0;
+}
+
+static struct irq_domain_ops sa1100_normal_irqdomain_ops = {
+	.map = sa1100_normal_irqdomain_map,
+	.xlate = irq_domain_xlate_onetwocell,
+};
+
+static struct irq_domain *sa1100_normal_irqdomain;
+
+static struct resource irq_resource =
+	DEFINE_RES_MEM_NAMED(0x90050000, SZ_64K, "irqs");
+
+static struct sa1100irq_state {
+	unsigned int	saved;
+	unsigned int	icmr;
+	unsigned int	iclr;
+	unsigned int	iccr;
+} sa1100irq_state;
+
+static int sa1100irq_suspend(void)
+{
+	struct sa1100irq_state *st = &sa1100irq_state;
+
+	st->saved = 1;
+	st->icmr = ICMR;
+	st->iclr = ICLR;
+	st->iccr = ICCR;
+
+	/*
+	 * Disable all GPIO-based interrupts.
+	 */
+	ICMR &= ~(IC_GPIO11_27|IC_GPIO10|IC_GPIO9|IC_GPIO8|IC_GPIO7|
+		  IC_GPIO6|IC_GPIO5|IC_GPIO4|IC_GPIO3|IC_GPIO2|
+		  IC_GPIO1|IC_GPIO0);
+
+	return 0;
+}
+
+static void sa1100irq_resume(void)
+{
+	struct sa1100irq_state *st = &sa1100irq_state;
+
+	if (st->saved) {
+		ICCR = st->iccr;
+		ICLR = st->iclr;
+
+		ICMR = st->icmr;
+	}
+}
+
+static struct syscore_ops sa1100irq_syscore_ops = {
+	.suspend	= sa1100irq_suspend,
+	.resume		= sa1100irq_resume,
+};
+
+static int __init sa1100irq_init_devicefs(void)
+{
+	register_syscore_ops(&sa1100irq_syscore_ops);
+	return 0;
+}
+
+device_initcall(sa1100irq_init_devicefs);
+
+static asmlinkage void __exception_irq_entry
+sa1100_handle_irq(struct pt_regs *regs)
+{
+	uint32_t icip, icmr, mask;
+
+	do {
+		icip = (ICIP);
+		icmr = (ICMR);
+		mask = icip & icmr;
+
+		if (mask == 0)
+			break;
+
+		handle_domain_irq(sa1100_normal_irqdomain,
+				ffs(mask) - 1, regs);
+	} while (1);
+}
+
+void __init sa1100_init_irq(void)
+{
+	request_resource(&iomem_resource, &irq_resource);
+
+	/* disable all IRQs */
+	ICMR = 0;
+
+	/* all IRQs are IRQ, not FIQ */
+	ICLR = 0;
+
+	/*
+	 * Whatever the doc says, this has to be set for the wait-on-irq
+	 * instruction to work... on a SA1100 rev 9 at least.
+	 */
+	ICCR = 1;
+
+	sa1100_normal_irqdomain = irq_domain_add_simple(NULL,
+			32, IRQ_GPIO0_SC,
+			&sa1100_normal_irqdomain_ops, NULL);
+
+	set_handle_irq(sa1100_handle_irq);
+
+	sa1100_init_gpio();
+}
-- 
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