irqchip/faraday: Replace moxa with ftintc010

The Moxa Art interrupt controller is very very likely just an instance
of the Faraday FTINTC010 interrupt controller from Faraday Technology.
An indication would be its close association with the FA526 ARM core
and the fact that the register layout is the same.

The implementation in irq-moxart.c can probably be right off replaced
with the irq-ftintc010.c driver by adding a compatible string, selecting
this irqchip from the machine and run.

As a bonus we have an irqchip driver supporting high/low and
rising/falling edges for the Moxa Art, and shared code with the Gemini
platform.
Acked-by: NOlof Johansson <olof@lixom.net>
Tested-by: NJonas Jensen <jonas.jensen@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

arch/arm/mach-moxart/Kconfig

@@ -3,8 +3,8 @@ menuconfig ARCH_MOXART
 	depends on ARCH_MULTI_V4
 	select CPU_FA526
 	select ARM_DMA_MEM_BUFFERABLE
+	select FARADAY_FTINTC010
 	select MOXART_TIMER
-	select GENERIC_IRQ_CHIP
 	select GPIOLIB
 	select PHYLIB if NETDEVICES
 	help

drivers/irqchip/Makefile

@@ -16,7 +16,6 @@ obj-$(CONFIG_ARCH_S3C24XX)		+= irq-s3c24xx.o
 obj-$(CONFIG_DW_APB_ICTL)		+= irq-dw-apb-ictl.o
 obj-$(CONFIG_METAG)			+= irq-metag-ext.o
 obj-$(CONFIG_METAG_PERFCOUNTER_IRQS)	+= irq-metag.o
-obj-$(CONFIG_ARCH_MOXART)		+= irq-moxart.o
 obj-$(CONFIG_CLPS711X_IRQCHIP)		+= irq-clps711x.o
 obj-$(CONFIG_OR1K_PIC)			+= irq-or1k-pic.o
 obj-$(CONFIG_ORION_IRQCHIP)		+= irq-orion.o

drivers/irqchip/irq-ftintc010.c

@@ -190,3 +190,5 @@ IRQCHIP_DECLARE(faraday, "faraday,ftintc010",
 		ft010_of_init_irq);
 IRQCHIP_DECLARE(gemini, "cortina,gemini-interrupt-controller",
 		ft010_of_init_irq);
+IRQCHIP_DECLARE(moxa, "moxa,moxart-ic",
+		ft010_of_init_irq);

drivers/irqchip/irq-moxart.c

-/*
- * MOXA ART SoCs IRQ chip driver.
- *
- * Copyright (C) 2013 Jonas Jensen
- *
- * Jonas Jensen <jonas.jensen@gmail.com>
- *
- * This file is licensed under the terms of the GNU General Public
- * License version 2.  This program is licensed "as is" without any
- * warranty of any kind, whether express or implied.
- */
-
-#include <linux/io.h>
-#include <linux/irq.h>
-#include <linux/irqchip.h>
-#include <linux/of.h>
-#include <linux/of_address.h>
-#include <linux/of_irq.h>
-#include <linux/irqdomain.h>
-
-#include <asm/exception.h>
-
-#define IRQ_SOURCE_REG		0
-#define IRQ_MASK_REG		0x04
-#define IRQ_CLEAR_REG		0x08
-#define IRQ_MODE_REG		0x0c
-#define IRQ_LEVEL_REG		0x10
-#define IRQ_STATUS_REG		0x14
-
-#define FIQ_SOURCE_REG		0x20
-#define FIQ_MASK_REG		0x24
-#define FIQ_CLEAR_REG		0x28
-#define FIQ_MODE_REG		0x2c
-#define FIQ_LEVEL_REG		0x30
-#define FIQ_STATUS_REG		0x34
-
-
-struct moxart_irq_data {
-	void __iomem *base;
-	struct irq_domain *domain;
-	unsigned int interrupt_mask;
-};
-
-static struct moxart_irq_data intc;
-
-static void __exception_irq_entry handle_irq(struct pt_regs *regs)
-{
-	u32 irqstat;
-	int hwirq;
-
-	irqstat = readl(intc.base + IRQ_STATUS_REG);
-
-	while (irqstat) {
-		hwirq = ffs(irqstat) - 1;
-		handle_IRQ(irq_linear_revmap(intc.domain, hwirq), regs);
-		irqstat &= ~(1 << hwirq);
-	}
-}
-
-static int __init moxart_of_intc_init(struct device_node *node,
-				      struct device_node *parent)
-{
-	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
-	int ret;
-	struct irq_chip_generic *gc;
-
-	intc.base = of_iomap(node, 0);
-	if (!intc.base) {
-		pr_err("%s: unable to map IC registers\n",
-		       node->full_name);
-		return -EINVAL;
-	}
-
-	intc.domain = irq_domain_add_linear(node, 32, &irq_generic_chip_ops,
-					    intc.base);
-	if (!intc.domain) {
-		pr_err("%s: unable to create IRQ domain\n", node->full_name);
-		return -EINVAL;
-	}
-
-	ret = irq_alloc_domain_generic_chips(intc.domain, 32, 1,
-					     "MOXARTINTC", handle_edge_irq,
-					     clr, 0, IRQ_GC_INIT_MASK_CACHE);
-	if (ret) {
-		pr_err("%s: could not allocate generic chip\n",
-		       node->full_name);
-		irq_domain_remove(intc.domain);
-		return -EINVAL;
-	}
-
-	ret = of_property_read_u32(node, "interrupt-mask",
-				   &intc.interrupt_mask);
-	if (ret)
-		pr_err("%s: could not read interrupt-mask DT property\n",
-		       node->full_name);
-
-	gc = irq_get_domain_generic_chip(intc.domain, 0);
-
-	gc->reg_base = intc.base;
-	gc->chip_types[0].regs.mask = IRQ_MASK_REG;
-	gc->chip_types[0].regs.ack = IRQ_CLEAR_REG;
-	gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_bit;
-	gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
-	gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
-
-	writel(0, intc.base + IRQ_MASK_REG);
-	writel(0xffffffff, intc.base + IRQ_CLEAR_REG);
-
-	writel(intc.interrupt_mask, intc.base + IRQ_MODE_REG);
-	writel(intc.interrupt_mask, intc.base + IRQ_LEVEL_REG);
-
-	set_handle_irq(handle_irq);
-
-	return 0;
-}
-IRQCHIP_DECLARE(moxa_moxart_ic, "moxa,moxart-ic", moxart_of_intc_init);