1/*
2 * Copyright 2006-2007, Michael Ellerman, IBM Corporation.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; version 2 of the
7 * License.
8 *
9 */
10
11#include <linux/irq.h>
12#include <linux/bitmap.h>
13#include <linux/msi.h>
14#include <asm/mpic.h>
15#include <asm/prom.h>
16#include <asm/hw_irq.h>
17#include <asm/ppc-pci.h>
18#include <asm/msi_bitmap.h>
19
20#include <sysdev/mpic.h>
21
22void mpic_msi_reserve_hwirq(struct mpic *mpic, irq_hw_number_t hwirq)
23{
24	/* The mpic calls this even when there is no allocator setup */
25	if (!mpic->msi_bitmap.bitmap)
26		return;
27
28	msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, hwirq);
29}
30
31#ifdef CONFIG_MPIC_U3_HT_IRQS
32static int mpic_msi_reserve_u3_hwirqs(struct mpic *mpic)
33{
34	irq_hw_number_t hwirq;
35	const struct irq_domain_ops *ops = mpic->irqhost->ops;
36	struct device_node *np;
37	int flags, index, i;
38	struct of_phandle_args oirq;
39
40	pr_debug("mpic: found U3, guessing msi allocator setup\n");
41
42	/* Reserve source numbers we know are reserved in the HW.
43	 *
44	 * This is a bit of a mix of U3 and U4 reserves but that's going
45	 * to work fine, we have plenty enugh numbers left so let's just
46	 * mark anything we don't like reserved.
47	 */
48	for (i = 0;   i < 8;   i++)
49		msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, i);
50
51	for (i = 42;  i < 46;  i++)
52		msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, i);
53
54	for (i = 100; i < 105; i++)
55		msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, i);
56
57	for (i = 124; i < mpic->num_sources; i++)
58		msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, i);
59
60
61	np = NULL;
62	while ((np = of_find_all_nodes(np))) {
63		pr_debug("mpic: mapping hwirqs for %s\n", np->full_name);
64
65		index = 0;
66		while (of_irq_parse_one(np, index++, &oirq) == 0) {
67			ops->xlate(mpic->irqhost, NULL, oirq.args,
68						oirq.args_count, &hwirq, &flags);
69			msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, hwirq);
70		}
71	}
72
73	return 0;
74}
75#else
76static int mpic_msi_reserve_u3_hwirqs(struct mpic *mpic)
77{
78	return -1;
79}
80#endif
81
82int mpic_msi_init_allocator(struct mpic *mpic)
83{
84	int rc;
85
86	rc = msi_bitmap_alloc(&mpic->msi_bitmap, mpic->num_sources,
87			      mpic->irqhost->of_node);
88	if (rc)
89		return rc;
90
91	rc = msi_bitmap_reserve_dt_hwirqs(&mpic->msi_bitmap);
92	if (rc > 0) {
93		if (mpic->flags & MPIC_U3_HT_IRQS)
94			rc = mpic_msi_reserve_u3_hwirqs(mpic);
95
96		if (rc) {
97			msi_bitmap_free(&mpic->msi_bitmap);
98			return rc;
99		}
100	}
101
102	return 0;
103}
104