--- zzzz-none-000/linux-3.10.107/arch/openrisc/kernel/irq.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/openrisc/kernel/irq.c	2021-02-04 17:41:59.000000000 +0000
@@ -16,11 +16,10 @@
 
 #include <linux/interrupt.h>
 #include <linux/init.h>
-#include <linux/of.h>
 #include <linux/ftrace.h>
 #include <linux/irq.h>
+#include <linux/irqchip.h>
 #include <linux/export.h>
-#include <linux/irqdomain.h>
 #include <linux/irqflags.h>
 
 /* read interrupt enabled status */
@@ -37,150 +36,19 @@
 }
 EXPORT_SYMBOL(arch_local_irq_restore);
 
-
-/* OR1K PIC implementation */
-
-/* We're a couple of cycles faster than the generic implementations with
- * these 'fast' versions.
- */
-
-static void or1k_pic_mask(struct irq_data *data)
-{
-	mtspr(SPR_PICMR, mfspr(SPR_PICMR) & ~(1UL << data->hwirq));
-}
-
-static void or1k_pic_unmask(struct irq_data *data)
-{
-	mtspr(SPR_PICMR, mfspr(SPR_PICMR) | (1UL << data->hwirq));
-}
-
-static void or1k_pic_ack(struct irq_data *data)
-{
-	/* EDGE-triggered interrupts need to be ack'ed in order to clear
-	 * the latch.
-	 * LEVEL-triggered interrupts do not need to be ack'ed; however,
-	 * ack'ing the interrupt has no ill-effect and is quicker than
-	 * trying to figure out what type it is...
-	 */
-
-	/* The OpenRISC 1000 spec says to write a 1 to the bit to ack the
-	 * interrupt, but the OR1200 does this backwards and requires a 0
-	 * to be written...
-	 */
-
-#ifdef CONFIG_OR1K_1200
-	/* There are two oddities with the OR1200 PIC implementation:
-	 * i)  LEVEL-triggered interrupts are latched and need to be cleared
-	 * ii) the interrupt latch is cleared by writing a 0 to the bit,
-	 *     as opposed to a 1 as mandated by the spec
-	 */
-
-	mtspr(SPR_PICSR, mfspr(SPR_PICSR) & ~(1UL << data->hwirq));
-#else
-	WARN(1, "Interrupt handling possibly broken\n");
-	mtspr(SPR_PICSR, (1UL << data->hwirq));
-#endif
-}
-
-static void or1k_pic_mask_ack(struct irq_data *data)
-{
-	/* Comments for pic_ack apply here, too */
-
-#ifdef CONFIG_OR1K_1200
-	mtspr(SPR_PICMR, mfspr(SPR_PICMR) & ~(1UL << data->hwirq));
-	mtspr(SPR_PICSR, mfspr(SPR_PICSR) & ~(1UL << data->hwirq));
-#else
-	WARN(1, "Interrupt handling possibly broken\n");
-	mtspr(SPR_PICMR, (1UL << data->hwirq));
-	mtspr(SPR_PICSR, (1UL << data->hwirq));
-#endif
-}
-
-#if 0
-static int or1k_pic_set_type(struct irq_data *data, unsigned int flow_type)
-{
-	/* There's nothing to do in the PIC configuration when changing
-	 * flow type.  Level and edge-triggered interrupts are both
-	 * supported, but it's PIC-implementation specific which type
-	 * is handled. */
-
-	return irq_setup_alt_chip(data, flow_type);
-}
-#endif
-
-static struct irq_chip or1k_dev = {
-	.name = "or1k-PIC",
-	.irq_unmask = or1k_pic_unmask,
-	.irq_mask = or1k_pic_mask,
-	.irq_ack = or1k_pic_ack,
-	.irq_mask_ack = or1k_pic_mask_ack,
-};
-
-static struct irq_domain *root_domain;
-
-static inline int pic_get_irq(int first)
+void __init init_IRQ(void)
 {
-	int hwirq;
-
-	hwirq = ffs(mfspr(SPR_PICSR) >> first);
-	if (!hwirq)
-		return NO_IRQ;
-	else
-		hwirq = hwirq + first -1;
-
-	return irq_find_mapping(root_domain, hwirq);
+	irqchip_init();
 }
 
+static void (*handle_arch_irq)(struct pt_regs *);
 
-static int or1k_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw)
+void __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
 {
-	irq_set_chip_and_handler_name(irq, &or1k_dev,
-				      handle_level_irq, "level");
-	irq_set_status_flags(irq, IRQ_LEVEL | IRQ_NOPROBE);
-
-	return 0;
-}
-
-static const struct irq_domain_ops or1k_irq_domain_ops = {
-	.xlate = irq_domain_xlate_onecell,
-	.map = or1k_map,
-};
-
-/*
- * This sets up the IRQ domain for the PIC built in to the OpenRISC
- * 1000 CPU.  This is the "root" domain as these are the interrupts
- * that directly trigger an exception in the CPU.
- */
-static void __init or1k_irq_init(void)
-{
-	struct device_node *intc = NULL;
-
-	/* The interrupt controller device node is mandatory */
-	intc = of_find_compatible_node(NULL, NULL, "opencores,or1k-pic");
-	BUG_ON(!intc);
-
-	/* Disable all interrupts until explicitly requested */
-	mtspr(SPR_PICMR, (0UL));
-
-	root_domain = irq_domain_add_linear(intc, 32,
-					    &or1k_irq_domain_ops, NULL);
-}
-
-void __init init_IRQ(void)
-{
-	or1k_irq_init();
+	handle_arch_irq = handle_irq;
 }
 
 void __irq_entry do_IRQ(struct pt_regs *regs)
 {
-	int irq = -1;
-	struct pt_regs *old_regs = set_irq_regs(regs);
-
-	irq_enter();
-
-	while ((irq = pic_get_irq(irq + 1)) != NO_IRQ)
-		generic_handle_irq(irq);
-
-	irq_exit();
-	set_irq_regs(old_regs);
+	handle_arch_irq(regs);
 }