blob: db057b6fe0c8bccf12710cee1c488d77def872f9 [file] [log] [blame]
Eric W. Biederman8b955b02006-10-04 02:16:55 -07001/*
2 * File: htirq.c
3 * Purpose: Hypertransport Interrupt Capability
4 *
5 * Copyright (C) 2006 Linux Networx
6 * Copyright (C) Eric Biederman <ebiederman@lnxi.com>
7 */
8
9#include <linux/irq.h>
10#include <linux/pci.h>
11#include <linux/spinlock.h>
12#include <linux/slab.h>
Eric W. Biederman95d77882006-10-04 02:17:01 -070013#include <linux/htirq.h>
Eric W. Biederman8b955b02006-10-04 02:16:55 -070014
15/* Global ht irq lock.
16 *
17 * This is needed to serialize access to the data port in hypertransport
18 * irq capability.
19 *
20 * With multiple simultaneous hypertransport irq devices it might pay
21 * to make this more fine grained. But start with simple, stupid, and correct.
22 */
23static DEFINE_SPINLOCK(ht_irq_lock);
24
25struct ht_irq_cfg {
26 struct pci_dev *dev;
Eric W. Biederman43539c382006-11-08 17:44:57 -080027 /* Update callback used to cope with buggy hardware */
28 ht_irq_update_t *update;
Eric W. Biederman8b955b02006-10-04 02:16:55 -070029 unsigned pos;
30 unsigned idx;
Eric W. Biedermanec683072006-11-08 17:44:57 -080031 struct ht_irq_msg msg;
Eric W. Biederman8b955b02006-10-04 02:16:55 -070032};
33
Eric W. Biedermanec683072006-11-08 17:44:57 -080034
35void write_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg)
Eric W. Biederman8b955b02006-10-04 02:16:55 -070036{
Thomas Gleixnerdced35a2011-03-28 17:49:12 +020037 struct ht_irq_cfg *cfg = irq_get_handler_data(irq);
Eric W. Biederman8b955b02006-10-04 02:16:55 -070038 unsigned long flags;
39 spin_lock_irqsave(&ht_irq_lock, flags);
Eric W. Biedermanec683072006-11-08 17:44:57 -080040 if (cfg->msg.address_lo != msg->address_lo) {
41 pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx);
42 pci_write_config_dword(cfg->dev, cfg->pos + 4, msg->address_lo);
43 }
44 if (cfg->msg.address_hi != msg->address_hi) {
45 pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx + 1);
46 pci_write_config_dword(cfg->dev, cfg->pos + 4, msg->address_hi);
47 }
Eric W. Biederman43539c382006-11-08 17:44:57 -080048 if (cfg->update)
49 cfg->update(cfg->dev, irq, msg);
Eric W. Biederman8b955b02006-10-04 02:16:55 -070050 spin_unlock_irqrestore(&ht_irq_lock, flags);
Eric W. Biedermanec683072006-11-08 17:44:57 -080051 cfg->msg = *msg;
Eric W. Biederman8b955b02006-10-04 02:16:55 -070052}
53
Eric W. Biedermanec683072006-11-08 17:44:57 -080054void fetch_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg)
Eric W. Biederman8b955b02006-10-04 02:16:55 -070055{
Thomas Gleixnerdced35a2011-03-28 17:49:12 +020056 struct ht_irq_cfg *cfg = irq_get_handler_data(irq);
Eric W. Biedermanec683072006-11-08 17:44:57 -080057 *msg = cfg->msg;
Eric W. Biederman8b955b02006-10-04 02:16:55 -070058}
59
Thomas Gleixnere9f7ac62010-09-28 17:22:09 +020060void mask_ht_irq(struct irq_data *data)
Eric W. Biederman8b955b02006-10-04 02:16:55 -070061{
Thomas Gleixnerdced35a2011-03-28 17:49:12 +020062 struct ht_irq_cfg *cfg = irq_data_get_irq_handler_data(data);
Thomas Gleixnere9f7ac62010-09-28 17:22:09 +020063 struct ht_irq_msg msg = cfg->msg;
Eric W. Biederman8b955b02006-10-04 02:16:55 -070064
Eric W. Biedermanec683072006-11-08 17:44:57 -080065 msg.address_lo |= 1;
Thomas Gleixnere9f7ac62010-09-28 17:22:09 +020066 write_ht_irq_msg(data->irq, &msg);
Eric W. Biederman8b955b02006-10-04 02:16:55 -070067}
68
Thomas Gleixnere9f7ac62010-09-28 17:22:09 +020069void unmask_ht_irq(struct irq_data *data)
Eric W. Biederman8b955b02006-10-04 02:16:55 -070070{
Thomas Gleixnerdced35a2011-03-28 17:49:12 +020071 struct ht_irq_cfg *cfg = irq_data_get_irq_handler_data(data);
Thomas Gleixnere9f7ac62010-09-28 17:22:09 +020072 struct ht_irq_msg msg = cfg->msg;
Eric W. Biederman8b955b02006-10-04 02:16:55 -070073
Eric W. Biedermanec683072006-11-08 17:44:57 -080074 msg.address_lo &= ~1;
Thomas Gleixnere9f7ac62010-09-28 17:22:09 +020075 write_ht_irq_msg(data->irq, &msg);
Eric W. Biederman8b955b02006-10-04 02:16:55 -070076}
77
78/**
Eric W. Biederman43539c382006-11-08 17:44:57 -080079 * __ht_create_irq - create an irq and attach it to a device.
Eric W. Biederman8b955b02006-10-04 02:16:55 -070080 * @dev: The hypertransport device to find the irq capability on.
81 * @idx: Which of the possible irqs to attach to.
Eric W. Biederman43539c382006-11-08 17:44:57 -080082 * @update: Function to be called when changing the htirq message
Eric W. Biederman8b955b02006-10-04 02:16:55 -070083 *
84 * The irq number of the new irq or a negative error value is returned.
85 */
Eric W. Biederman43539c382006-11-08 17:44:57 -080086int __ht_create_irq(struct pci_dev *dev, int idx, ht_irq_update_t *update)
Eric W. Biederman8b955b02006-10-04 02:16:55 -070087{
88 struct ht_irq_cfg *cfg;
89 unsigned long flags;
90 u32 data;
91 int max_irq;
92 int pos;
Yinghai Lu1f3addc2008-09-05 10:03:37 -070093 int irq;
Yinghai Lu56b581e2009-04-27 18:02:46 -070094 int node;
Eric W. Biederman8b955b02006-10-04 02:16:55 -070095
Michael Ellerman120a50d2006-11-22 18:26:19 +110096 pos = pci_find_ht_capability(dev, HT_CAPTYPE_IRQ);
Eric W. Biederman8b955b02006-10-04 02:16:55 -070097 if (!pos)
98 return -EINVAL;
99
100 /* Verify the idx I want to use is in range */
101 spin_lock_irqsave(&ht_irq_lock, flags);
102 pci_write_config_byte(dev, pos + 2, 1);
103 pci_read_config_dword(dev, pos + 4, &data);
104 spin_unlock_irqrestore(&ht_irq_lock, flags);
105
106 max_irq = (data >> 16) & 0xff;
107 if ( idx > max_irq)
108 return -EINVAL;
109
110 cfg = kmalloc(sizeof(*cfg), GFP_KERNEL);
111 if (!cfg)
112 return -ENOMEM;
113
114 cfg->dev = dev;
Eric W. Biederman43539c382006-11-08 17:44:57 -0800115 cfg->update = update;
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700116 cfg->pos = pos;
117 cfg->idx = 0x10 + (idx * 2);
Eric W. Biedermanec683072006-11-08 17:44:57 -0800118 /* Initialize msg to a value that will never match the first write. */
119 cfg->msg.address_lo = 0xffffffff;
120 cfg->msg.address_hi = 0xffffffff;
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700121
Yinghai Lu56b581e2009-04-27 18:02:46 -0700122 node = dev_to_node(&dev->dev);
123 irq = create_irq_nr(0, node);
Thomas Gleixner2cc21ef2008-10-15 14:16:55 +0200124
Dean Nelsone65ef882008-09-05 09:07:20 -0500125 if (irq <= 0) {
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700126 kfree(cfg);
127 return -EBUSY;
128 }
Thomas Gleixnerdced35a2011-03-28 17:49:12 +0200129 irq_set_handler_data(irq, cfg);
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700130
131 if (arch_setup_ht_irq(irq, dev) < 0) {
132 ht_destroy_irq(irq);
133 return -EBUSY;
134 }
135
136 return irq;
137}
138
139/**
Eric W. Biederman43539c382006-11-08 17:44:57 -0800140 * ht_create_irq - create an irq and attach it to a device.
141 * @dev: The hypertransport device to find the irq capability on.
142 * @idx: Which of the possible irqs to attach to.
143 *
144 * ht_create_irq needs to be called for all hypertransport devices
145 * that generate irqs.
146 *
147 * The irq number of the new irq or a negative error value is returned.
148 */
149int ht_create_irq(struct pci_dev *dev, int idx)
150{
151 return __ht_create_irq(dev, idx, NULL);
152}
153
154/**
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700155 * ht_destroy_irq - destroy an irq created with ht_create_irq
Randy Dunlapcffb2fa2009-04-10 15:17:50 -0700156 * @irq: irq to be destroyed
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700157 *
158 * This reverses ht_create_irq removing the specified irq from
159 * existence. The irq should be free before this happens.
160 */
161void ht_destroy_irq(unsigned int irq)
162{
163 struct ht_irq_cfg *cfg;
164
Thomas Gleixnerdced35a2011-03-28 17:49:12 +0200165 cfg = irq_get_handler_data(irq);
166 irq_set_chip(irq, NULL);
167 irq_set_handler_data(irq, NULL);
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700168 destroy_irq(irq);
169
170 kfree(cfg);
171}
172
Eric W. Biederman43539c382006-11-08 17:44:57 -0800173EXPORT_SYMBOL(__ht_create_irq);
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700174EXPORT_SYMBOL(ht_create_irq);
175EXPORT_SYMBOL(ht_destroy_irq);