irqchip/ath79-misc: Move the MISC driver from arch/mips/ath79/

The driver stays the same but the initialization changes a bit.
For OF boards we now get the memory map from the OF node and use
a linear mapping instead of the legacy mapping. For legacy boards
we still use a legacy mapping and just pass down all the parameters
from the board init code.

Signed-off-by: Alban Bedel <albeu@free.fr>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1453553867-27003-1-git-send-email-albeu@free.fr
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

2 files changed, 190 insertions, 0 deletions

diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 18caacb60d58..b873d4a081b4 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -1,5 +1,6 @@
 obj-$(CONFIG_IRQCHIP)			+= irqchip.o
 
+obj-$(CONFIG_ATH79)			+= irq-ath79-misc.o
 obj-$(CONFIG_ARCH_BCM2835)		+= irq-bcm2835.o
 obj-$(CONFIG_ARCH_BCM2835)		+= irq-bcm2836.o
 obj-$(CONFIG_ARCH_EXYNOS)		+= exynos-combiner.o
diff --git a/drivers/irqchip/irq-ath79-misc.c b/drivers/irqchip/irq-ath79-misc.c
new file mode 100644
index 000000000000..aa7290784636
--- /dev/null
+++ b/drivers/irqchip/irq-ath79-misc.c
@@ -0,0 +1,189 @@
+/*
+ *  Atheros AR71xx/AR724x/AR913x MISC interrupt controller
+ *
+ *  Copyright (C) 2015 Alban Bedel <albeu@free.fr>
+ *  Copyright (C) 2010-2011 Jaiganesh Narayanan <jnarayanan@atheros.com>
+ *  Copyright (C) 2008-2011 Gabor Juhos <juhosg@openwrt.org>
+ *  Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
+ *
+ *  Parts of this file are based on Atheros' 2.6.15/2.6.31 BSP
+ *
+ *  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/irqchip.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define AR71XX_RESET_REG_MISC_INT_STATUS	0
+#define AR71XX_RESET_REG_MISC_INT_ENABLE	4
+
+#define ATH79_MISC_IRQ_COUNT			32
+
+static void ath79_misc_irq_handler(struct irq_desc *desc)
+{
+	struct irq_domain *domain = irq_desc_get_handler_data(desc);
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	void __iomem *base = domain->host_data;
+	u32 pending;
+
+	chained_irq_enter(chip, desc);
+
+	pending = __raw_readl(base + AR71XX_RESET_REG_MISC_INT_STATUS) &
+		  __raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
+
+	if (!pending) {
+		spurious_interrupt();
+		chained_irq_exit(chip, desc);
+		return;
+	}
+
+	while (pending) {
+		int bit = __ffs(pending);
+
+		generic_handle_irq(irq_linear_revmap(domain, bit));
+		pending &= ~BIT(bit);
+	}
+
+	chained_irq_exit(chip, desc);
+}
+
+static void ar71xx_misc_irq_unmask(struct irq_data *d)
+{
+	void __iomem *base = irq_data_get_irq_chip_data(d);
+	unsigned int irq = d->hwirq;
+	u32 t;
+
+	t = __raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
+	__raw_writel(t | BIT(irq), base + AR71XX_RESET_REG_MISC_INT_ENABLE);
+
+	/* flush write */
+	__raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
+}
+
+static void ar71xx_misc_irq_mask(struct irq_data *d)
+{
+	void __iomem *base = irq_data_get_irq_chip_data(d);
+	unsigned int irq = d->hwirq;
+	u32 t;
+
+	t = __raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
+	__raw_writel(t & ~BIT(irq), base + AR71XX_RESET_REG_MISC_INT_ENABLE);
+
+	/* flush write */
+	__raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
+}
+
+static void ar724x_misc_irq_ack(struct irq_data *d)
+{
+	void __iomem *base = irq_data_get_irq_chip_data(d);
+	unsigned int irq = d->hwirq;
+	u32 t;
+
+	t = __raw_readl(base + AR71XX_RESET_REG_MISC_INT_STATUS);
+	__raw_writel(t & ~BIT(irq), base + AR71XX_RESET_REG_MISC_INT_STATUS);
+
+	/* flush write */
+	__raw_readl(base + AR71XX_RESET_REG_MISC_INT_STATUS);
+}
+
+static struct irq_chip ath79_misc_irq_chip = {
+	.name		= "MISC",
+	.irq_unmask	= ar71xx_misc_irq_unmask,
+	.irq_mask	= ar71xx_misc_irq_mask,
+};
+
+static int misc_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw)
+{
+	irq_set_chip_and_handler(irq, &ath79_misc_irq_chip, handle_level_irq);
+	irq_set_chip_data(irq, d->host_data);
+	return 0;
+}
+
+static const struct irq_domain_ops misc_irq_domain_ops = {
+	.xlate = irq_domain_xlate_onecell,
+	.map = misc_map,
+};
+
+static void __init ath79_misc_intc_domain_init(
+	struct irq_domain *domain, int irq)
+{
+	void __iomem *base = domain->host_data;
+
+	/* Disable and clear all interrupts */
+	__raw_writel(0, base + AR71XX_RESET_REG_MISC_INT_ENABLE);
+	__raw_writel(0, base + AR71XX_RESET_REG_MISC_INT_STATUS);
+
+	irq_set_chained_handler_and_data(irq, ath79_misc_irq_handler, domain);
+}
+
+static int __init ath79_misc_intc_of_init(
+	struct device_node *node, struct device_node *parent)
+{
+	struct irq_domain *domain;
+	void __iomem *base;
+	int irq;
+
+	irq = irq_of_parse_and_map(node, 0);
+	if (!irq) {
+		pr_err("Failed to get MISC IRQ\n");
+		return -EINVAL;
+	}
+
+	base = of_iomap(node, 0);
+	if (!base) {
+		pr_err("Failed to get MISC IRQ registers\n");
+		return -ENOMEM;
+	}
+
+	domain = irq_domain_add_linear(node, ATH79_MISC_IRQ_COUNT,
+				&misc_irq_domain_ops, base);
+	if (!domain) {
+		pr_err("Failed to add MISC irqdomain\n");
+		return -EINVAL;
+	}
+
+	ath79_misc_intc_domain_init(domain, irq);
+	return 0;
+}
+
+static int __init ar7100_misc_intc_of_init(
+	struct device_node *node, struct device_node *parent)
+{
+	ath79_misc_irq_chip.irq_mask_ack = ar71xx_misc_irq_mask;
+	return ath79_misc_intc_of_init(node, parent);
+}
+
+IRQCHIP_DECLARE(ar7100_misc_intc, "qca,ar7100-misc-intc",
+		ar7100_misc_intc_of_init);
+
+static int __init ar7240_misc_intc_of_init(
+	struct device_node *node, struct device_node *parent)
+{
+	ath79_misc_irq_chip.irq_ack = ar724x_misc_irq_ack;
+	return ath79_misc_intc_of_init(node, parent);
+}
+
+IRQCHIP_DECLARE(ar7240_misc_intc, "qca,ar7240-misc-intc",
+		ar7240_misc_intc_of_init);
+
+void __init ath79_misc_irq_init(void __iomem *regs, int irq,
+				int irq_base, bool is_ar71xx)
+{
+	struct irq_domain *domain;
+
+	if (is_ar71xx)
+		ath79_misc_irq_chip.irq_mask_ack = ar71xx_misc_irq_mask;
+	else
+		ath79_misc_irq_chip.irq_ack = ar724x_misc_irq_ack;
+
+	domain = irq_domain_add_legacy(NULL, ATH79_MISC_IRQ_COUNT,
+			irq_base, 0, &misc_irq_domain_ops, regs);
+	if (!domain)
+		panic("Failed to create MISC irqdomain");
+
+	ath79_misc_intc_domain_init(domain, irq);
+}