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 struct irq_host_ops *ops = mpic->irqhost->ops;
36 struct device_node *np;
37 int flags, index, i;
38 struct of_irq 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 for (i = 0; i < 8; i++)
44 msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, i);
45
46 for (i = 42; i < 46; i++)
47 msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, i);
48
49 for (i = 100; i < 105; i++)
50 msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, i);
51
52 np = NULL;
53 while ((np = of_find_all_nodes(np))) {
54 pr_debug("mpic: mapping hwirqs for %s\n", np->full_name);
55
56 index = 0;
57 while (of_irq_map_one(np, index++, &oirq) == 0) {
58 ops->xlate(mpic->irqhost, NULL, oirq.specifier,
59 oirq.size, &hwirq, &flags);
60 msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, hwirq);
61 }
62 }
63
64 return 0;
65 }
66 #else
mpic_msi_reserve_u3_hwirqs(struct mpic * mpic)67 static int mpic_msi_reserve_u3_hwirqs(struct mpic *mpic)
68 {
69 return -1;
70 }
71 #endif
72
mpic_msi_init_allocator(struct mpic * mpic)73 int mpic_msi_init_allocator(struct mpic *mpic)
74 {
75 int rc;
76
77 rc = msi_bitmap_alloc(&mpic->msi_bitmap, mpic->irq_count,
78 mpic->irqhost->of_node);
79 if (rc)
80 return rc;
81
82 rc = msi_bitmap_reserve_dt_hwirqs(&mpic->msi_bitmap);
83 if (rc > 0) {
84 if (mpic->flags & MPIC_U3_HT_IRQS)
85 rc = mpic_msi_reserve_u3_hwirqs(mpic);
86
87 if (rc) {
88 msi_bitmap_free(&mpic->msi_bitmap);
89 return rc;
90 }
91 }
92
93 return 0;
94 }
95