1/*
2 * IRQ domain support for SH INTC subsystem
3 *
4 * Copyright (C) 2012  Paul Mundt
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License.  See the file "COPYING" in the main directory of this archive
8 * for more details.
9 */
10#define pr_fmt(fmt) "intc: " fmt
11
12#include <linux/irqdomain.h>
13#include <linux/sh_intc.h>
14#include <linux/export.h>
15#include "internals.h"
16
17/**
18 * intc_irq_domain_evt_xlate() - Generic xlate for vectored IRQs.
19 *
20 * This takes care of exception vector to hwirq translation through
21 * by way of evt2irq() translation.
22 *
23 * Note: For platforms that use a flat vector space without INTEVT this
24 * basically just mimics irq_domain_xlate_onecell() by way of a nopped
25 * out evt2irq() implementation.
26 */
27static int intc_evt_xlate(struct irq_domain *d, struct device_node *ctrlr,
28			  const u32 *intspec, unsigned int intsize,
29			  unsigned long *out_hwirq, unsigned int *out_type)
30{
31	if (WARN_ON(intsize < 1))
32		return -EINVAL;
33
34	*out_hwirq = evt2irq(intspec[0]);
35	*out_type = IRQ_TYPE_NONE;
36
37	return 0;
38}
39
40static const struct irq_domain_ops intc_evt_ops = {
41	.xlate		= intc_evt_xlate,
42};
43
44void __init intc_irq_domain_init(struct intc_desc_int *d,
45				 struct intc_hw_desc *hw)
46{
47	unsigned int irq_base, irq_end;
48
49	/*
50	 * Quick linear revmap check
51	 */
52	irq_base = evt2irq(hw->vectors[0].vect);
53	irq_end = evt2irq(hw->vectors[hw->nr_vectors - 1].vect);
54
55	/*
56	 * Linear domains have a hard-wired assertion that IRQs start at
57	 * 0 in order to make some performance optimizations. Lamely
58	 * restrict the linear case to these conditions here, taking the
59	 * tree penalty for linear cases with non-zero hwirq bases.
60	 */
61	if (irq_base == 0 && irq_end == (irq_base + hw->nr_vectors - 1))
62		d->domain = irq_domain_add_linear(NULL, hw->nr_vectors,
63						  &intc_evt_ops, NULL);
64	else
65		d->domain = irq_domain_add_tree(NULL, &intc_evt_ops, NULL);
66
67	BUG_ON(!d->domain);
68}
69