1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
|
/*
* Dynamic IRQ management
*
* Copyright (C) 2010 Paul Mundt
*
* Modelled after arch/x86/kernel/apic/io_apic.c
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#define pr_fmt(fmt) "intc: " fmt
#include <linux/irq.h>
#include <linux/bitmap.h>
#include <linux/spinlock.h>
#include "internals.h" /* only for activate_irq() damage.. */
/*
* The intc_irq_map provides a global map of bound IRQ vectors for a
* given platform. Allocation of IRQs are either static through the CPU
* vector map, or dynamic in the case of board mux vectors or MSI.
*
* As this is a central point for all IRQ controllers on the system,
* each of the available sources are mapped out here. This combined with
* sparseirq makes it quite trivial to keep the vector map tightly packed
* when dynamically creating IRQs, as well as tying in to otherwise
* unused irq_desc positions in the sparse array.
*/
static DECLARE_BITMAP(intc_irq_map, NR_IRQS);
static DEFINE_RAW_SPINLOCK(vector_lock);
/*
* Dynamic IRQ allocation and deallocation
*/
unsigned int create_irq_nr(unsigned int irq_want, int node)
{
unsigned int irq = 0, new;
unsigned long flags;
struct irq_desc *desc;
raw_spin_lock_irqsave(&vector_lock, flags);
/*
* First try the wanted IRQ
*/
if (test_and_set_bit(irq_want, intc_irq_map) == 0) {
new = irq_want;
} else {
/* .. then fall back to scanning. */
new = find_first_zero_bit(intc_irq_map, nr_irqs);
if (unlikely(new == nr_irqs))
goto out_unlock;
__set_bit(new, intc_irq_map);
}
desc = irq_to_desc_alloc_node(new, node);
if (unlikely(!desc)) {
pr_err("can't get irq_desc for %d\n", new);
goto out_unlock;
}
desc = move_irq_desc(desc, node);
irq = new;
out_unlock:
raw_spin_unlock_irqrestore(&vector_lock, flags);
if (irq > 0) {
dynamic_irq_init(irq);
activate_irq(irq);
}
return irq;
}
int create_irq(void)
{
int nid = cpu_to_node(smp_processor_id());
int irq;
irq = create_irq_nr(NR_IRQS_LEGACY, nid);
if (irq == 0)
irq = -1;
return irq;
}
void destroy_irq(unsigned int irq)
{
unsigned long flags;
dynamic_irq_cleanup(irq);
raw_spin_lock_irqsave(&vector_lock, flags);
__clear_bit(irq, intc_irq_map);
raw_spin_unlock_irqrestore(&vector_lock, flags);
}
int reserve_irq_vector(unsigned int irq)
{
unsigned long flags;
int ret = 0;
raw_spin_lock_irqsave(&vector_lock, flags);
if (test_and_set_bit(irq, intc_irq_map))
ret = -EBUSY;
raw_spin_unlock_irqrestore(&vector_lock, flags);
return ret;
}
void reserve_intc_vectors(struct intc_vect *vectors, unsigned int nr_vecs)
{
unsigned long flags;
int i;
raw_spin_lock_irqsave(&vector_lock, flags);
for (i = 0; i < nr_vecs; i++)
__set_bit(evt2irq(vectors[i].vect), intc_irq_map);
raw_spin_unlock_irqrestore(&vector_lock, flags);
}
void reserve_irq_legacy(void)
{
unsigned long flags;
int i, j;
raw_spin_lock_irqsave(&vector_lock, flags);
j = find_first_bit(intc_irq_map, nr_irqs);
for (i = 0; i < j; i++)
__set_bit(i, intc_irq_map);
raw_spin_unlock_irqrestore(&vector_lock, flags);
}
|
