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
mpic_msi_reserve_hwirq(struct mpic * mpic,irq_hw_number_t hwirq)22 void 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
mpic_msi_reserve_u3_hwirqs(struct mpic * mpic)32 static 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
mpic_msi_reserve_u3_hwirqs(struct mpic * mpic)76 static int mpic_msi_reserve_u3_hwirqs(struct mpic *mpic)
77 {
78 return -1;
79 }
80 #endif
81
mpic_msi_init_allocator(struct mpic * mpic)82 int mpic_msi_init_allocator(struct mpic *mpic)
83 {
84 int rc;
85
86 rc = msi_bitmap_alloc(&mpic->msi_bitmap, mpic->num_sources,
87 irq_domain_get_of_node(mpic->irqhost));
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