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
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
|
/*
* File: htirq.c
* Purpose: Hypertransport Interrupt Capability
*
* Copyright (C) 2006 Linux Networx
* Copyright (C) Eric Biederman <ebiederman@lnxi.com>
*/
#include <linux/irq.h>
#include <linux/pci.h>
#include <linux/spinlock.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/htirq.h>
/* Global ht irq lock.
*
* This is needed to serialize access to the data port in hypertransport
* irq capability.
*
* With multiple simultaneous hypertransport irq devices it might pay
* to make this more fine grained. But start with simple, stupid, and correct.
*/
static DEFINE_SPINLOCK(ht_irq_lock);
struct ht_irq_cfg {
struct pci_dev *dev;
/* Update callback used to cope with buggy hardware */
ht_irq_update_t *update;
unsigned pos;
unsigned idx;
struct ht_irq_msg msg;
};
void write_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg)
{
struct ht_irq_cfg *cfg = irq_get_handler_data(irq);
unsigned long flags;
spin_lock_irqsave(&ht_irq_lock, flags);
if (cfg->msg.address_lo != msg->address_lo) {
pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx);
pci_write_config_dword(cfg->dev, cfg->pos + 4, msg->address_lo);
}
if (cfg->msg.address_hi != msg->address_hi) {
pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx + 1);
pci_write_config_dword(cfg->dev, cfg->pos + 4, msg->address_hi);
}
if (cfg->update)
cfg->update(cfg->dev, irq, msg);
spin_unlock_irqrestore(&ht_irq_lock, flags);
cfg->msg = *msg;
}
void fetch_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg)
{
struct ht_irq_cfg *cfg = irq_get_handler_data(irq);
*msg = cfg->msg;
}
void mask_ht_irq(struct irq_data *data)
{
struct ht_irq_cfg *cfg = irq_data_get_irq_handler_data(data);
struct ht_irq_msg msg = cfg->msg;
msg.address_lo |= 1;
write_ht_irq_msg(data->irq, &msg);
}
void unmask_ht_irq(struct irq_data *data)
{
struct ht_irq_cfg *cfg = irq_data_get_irq_handler_data(data);
struct ht_irq_msg msg = cfg->msg;
msg.address_lo &= ~1;
write_ht_irq_msg(data->irq, &msg);
}
/**
* __ht_create_irq - create an irq and attach it to a device.
* @dev: The hypertransport device to find the irq capability on.
* @idx: Which of the possible irqs to attach to.
* @update: Function to be called when changing the htirq message
*
* The irq number of the new irq or a negative error value is returned.
*/
int __ht_create_irq(struct pci_dev *dev, int idx, ht_irq_update_t *update)
{
struct ht_irq_cfg *cfg;
unsigned long flags;
u32 data;
int max_irq;
int pos;
int irq;
int node;
pos = pci_find_ht_capability(dev, HT_CAPTYPE_IRQ);
if (!pos)
return -EINVAL;
/* Verify the idx I want to use is in range */
spin_lock_irqsave(&ht_irq_lock, flags);
pci_write_config_byte(dev, pos + 2, 1);
pci_read_config_dword(dev, pos + 4, &data);
spin_unlock_irqrestore(&ht_irq_lock, flags);
max_irq = (data >> 16) & 0xff;
if ( idx > max_irq)
return -EINVAL;
cfg = kmalloc(sizeof(*cfg), GFP_KERNEL);
if (!cfg)
return -ENOMEM;
cfg->dev = dev;
cfg->update = update;
cfg->pos = pos;
cfg->idx = 0x10 + (idx * 2);
/* Initialize msg to a value that will never match the first write. */
cfg->msg.address_lo = 0xffffffff;
cfg->msg.address_hi = 0xffffffff;
node = dev_to_node(&dev->dev);
irq = create_irq_nr(0, node);
if (irq <= 0) {
kfree(cfg);
return -EBUSY;
}
irq_set_handler_data(irq, cfg);
if (arch_setup_ht_irq(irq, dev) < 0) {
ht_destroy_irq(irq);
return -EBUSY;
}
return irq;
}
/**
* ht_create_irq - create an irq and attach it to a device.
* @dev: The hypertransport device to find the irq capability on.
* @idx: Which of the possible irqs to attach to.
*
* ht_create_irq needs to be called for all hypertransport devices
* that generate irqs.
*
* The irq number of the new irq or a negative error value is returned.
*/
int ht_create_irq(struct pci_dev *dev, int idx)
{
return __ht_create_irq(dev, idx, NULL);
}
/**
* ht_destroy_irq - destroy an irq created with ht_create_irq
* @irq: irq to be destroyed
*
* This reverses ht_create_irq removing the specified irq from
* existence. The irq should be free before this happens.
*/
void ht_destroy_irq(unsigned int irq)
{
struct ht_irq_cfg *cfg;
cfg = irq_get_handler_data(irq);
irq_set_chip(irq, NULL);
irq_set_handler_data(irq, NULL);
destroy_irq(irq);
kfree(cfg);
}
EXPORT_SYMBOL(__ht_create_irq);
EXPORT_SYMBOL(ht_create_irq);
EXPORT_SYMBOL(ht_destroy_irq);
|
