1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright 2006-2007, Michael Ellerman, IBM Corporation.
4 */
5
6 #include <linux/irq.h>
7 #include <linux/bitmap.h>
8 #include <linux/msi.h>
9 #include <asm/mpic.h>
10 #include <asm/prom.h>
11 #include <asm/hw_irq.h>
12 #include <asm/ppc-pci.h>
13 #include <asm/msi_bitmap.h>
14
15 #include <sysdev/mpic.h>
16
mpic_msi_reserve_hwirq(struct mpic * mpic,irq_hw_number_t hwirq)17 void mpic_msi_reserve_hwirq(struct mpic *mpic, irq_hw_number_t hwirq)
18 {
19 /* The mpic calls this even when there is no allocator setup */
20 if (!mpic->msi_bitmap.bitmap)
21 return;
22
23 msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, hwirq);
24 }
25
26 #ifdef CONFIG_MPIC_U3_HT_IRQS
mpic_msi_reserve_u3_hwirqs(struct mpic * mpic)27 static int mpic_msi_reserve_u3_hwirqs(struct mpic *mpic)
28 {
29 irq_hw_number_t hwirq;
30 const struct irq_domain_ops *ops = mpic->irqhost->ops;
31 struct device_node *np;
32 int flags, index, i;
33 struct of_phandle_args oirq;
34
35 pr_debug("mpic: found U3, guessing msi allocator setup\n");
36
37 /* Reserve source numbers we know are reserved in the HW.
38 *
39 * This is a bit of a mix of U3 and U4 reserves but that's going
40 * to work fine, we have plenty enugh numbers left so let's just
41 * mark anything we don't like reserved.
42 */
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 for (i = 124; i < mpic->num_sources; i++)
53 msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, i);
54
55
56 np = NULL;
57 while ((np = of_find_all_nodes(np))) {
58 pr_debug("mpic: mapping hwirqs for %pOF\n", np);
59
60 index = 0;
61 while (of_irq_parse_one(np, index++, &oirq) == 0) {
62 ops->xlate(mpic->irqhost, NULL, oirq.args,
63 oirq.args_count, &hwirq, &flags);
64 msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, hwirq);
65 }
66 }
67
68 return 0;
69 }
70 #else
mpic_msi_reserve_u3_hwirqs(struct mpic * mpic)71 static int mpic_msi_reserve_u3_hwirqs(struct mpic *mpic)
72 {
73 return -1;
74 }
75 #endif
76
mpic_msi_init_allocator(struct mpic * mpic)77 int mpic_msi_init_allocator(struct mpic *mpic)
78 {
79 int rc;
80
81 rc = msi_bitmap_alloc(&mpic->msi_bitmap, mpic->num_sources,
82 irq_domain_get_of_node(mpic->irqhost));
83 if (rc)
84 return rc;
85
86 rc = msi_bitmap_reserve_dt_hwirqs(&mpic->msi_bitmap);
87 if (rc > 0) {
88 if (mpic->flags & MPIC_U3_HT_IRQS)
89 rc = mpic_msi_reserve_u3_hwirqs(mpic);
90
91 if (rc) {
92 msi_bitmap_free(&mpic->msi_bitmap);
93 return rc;
94 }
95 }
96
97 return 0;
98 }
99
