blob: 6e373ea57b32834df2076b26b4f0d72941933644 [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>
Paul Gortmaker363c75d2011-05-27 09:37:25 -040012#include <linux/export.h>
Eric W. Biederman8b955b02006-10-04 02:16:55 -070013#include <linux/slab.h>
Eric W. Biederman95d77882006-10-04 02:17:01 -070014#include <linux/htirq.h>
Eric W. Biederman8b955b02006-10-04 02:16:55 -070015
16/* Global ht irq lock.
17 *
18 * This is needed to serialize access to the data port in hypertransport
19 * irq capability.
20 *
21 * With multiple simultaneous hypertransport irq devices it might pay
22 * to make this more fine grained. But start with simple, stupid, and correct.
23 */
24static DEFINE_SPINLOCK(ht_irq_lock);
25
26struct ht_irq_cfg {
27 struct pci_dev *dev;
Eric W. Biederman43539c32006-11-08 17:44:57 -080028 /* Update callback used to cope with buggy hardware */
29 ht_irq_update_t *update;
Eric W. Biederman8b955b02006-10-04 02:16:55 -070030 unsigned pos;
31 unsigned idx;
Eric W. Biedermanec683072006-11-08 17:44:57 -080032 struct ht_irq_msg msg;
Eric W. Biederman8b955b02006-10-04 02:16:55 -070033};
34
Eric W. Biedermanec683072006-11-08 17:44:57 -080035
36void write_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg)
Eric W. Biederman8b955b02006-10-04 02:16:55 -070037{
Thomas Gleixnerdced35a2011-03-28 17:49:12 +020038 struct ht_irq_cfg *cfg = irq_get_handler_data(irq);
Eric W. Biederman8b955b02006-10-04 02:16:55 -070039 unsigned long flags;
40 spin_lock_irqsave(&ht_irq_lock, flags);
Eric W. Biedermanec683072006-11-08 17:44:57 -080041 if (cfg->msg.address_lo != msg->address_lo) {
42 pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx);
43 pci_write_config_dword(cfg->dev, cfg->pos + 4, msg->address_lo);
44 }
45 if (cfg->msg.address_hi != msg->address_hi) {
46 pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx + 1);
47 pci_write_config_dword(cfg->dev, cfg->pos + 4, msg->address_hi);
48 }
Eric W. Biederman43539c32006-11-08 17:44:57 -080049 if (cfg->update)
50 cfg->update(cfg->dev, irq, msg);
Eric W. Biederman8b955b02006-10-04 02:16:55 -070051 spin_unlock_irqrestore(&ht_irq_lock, flags);
Eric W. Biedermanec683072006-11-08 17:44:57 -080052 cfg->msg = *msg;
Eric W. Biederman8b955b02006-10-04 02:16:55 -070053}
54
Eric W. Biedermanec683072006-11-08 17:44:57 -080055void fetch_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg)
Eric W. Biederman8b955b02006-10-04 02:16:55 -070056{
Thomas Gleixnerdced35a2011-03-28 17:49:12 +020057 struct ht_irq_cfg *cfg = irq_get_handler_data(irq);
Eric W. Biedermanec683072006-11-08 17:44:57 -080058 *msg = cfg->msg;
Eric W. Biederman8b955b02006-10-04 02:16:55 -070059}
60
Thomas Gleixnere9f7ac62010-09-28 17:22:09 +020061void mask_ht_irq(struct irq_data *data)
Eric W. Biederman8b955b02006-10-04 02:16:55 -070062{
Thomas Gleixnerdced35a2011-03-28 17:49:12 +020063 struct ht_irq_cfg *cfg = irq_data_get_irq_handler_data(data);
Thomas Gleixnere9f7ac62010-09-28 17:22:09 +020064 struct ht_irq_msg msg = cfg->msg;
Eric W. Biederman8b955b02006-10-04 02:16:55 -070065
Eric W. Biedermanec683072006-11-08 17:44:57 -080066 msg.address_lo |= 1;
Thomas Gleixnere9f7ac62010-09-28 17:22:09 +020067 write_ht_irq_msg(data->irq, &msg);
Eric W. Biederman8b955b02006-10-04 02:16:55 -070068}
69
Thomas Gleixnere9f7ac62010-09-28 17:22:09 +020070void unmask_ht_irq(struct irq_data *data)
Eric W. Biederman8b955b02006-10-04 02:16:55 -070071{
Thomas Gleixnerdced35a2011-03-28 17:49:12 +020072 struct ht_irq_cfg *cfg = irq_data_get_irq_handler_data(data);
Thomas Gleixnere9f7ac62010-09-28 17:22:09 +020073 struct ht_irq_msg msg = cfg->msg;
Eric W. Biederman8b955b02006-10-04 02:16:55 -070074
Eric W. Biedermanec683072006-11-08 17:44:57 -080075 msg.address_lo &= ~1;
Thomas Gleixnere9f7ac62010-09-28 17:22:09 +020076 write_ht_irq_msg(data->irq, &msg);
Eric W. Biederman8b955b02006-10-04 02:16:55 -070077}
78
79/**
Eric W. Biederman43539c32006-11-08 17:44:57 -080080 * __ht_create_irq - create an irq and attach it to a device.
Eric W. Biederman8b955b02006-10-04 02:16:55 -070081 * @dev: The hypertransport device to find the irq capability on.
82 * @idx: Which of the possible irqs to attach to.
Eric W. Biederman43539c32006-11-08 17:44:57 -080083 * @update: Function to be called when changing the htirq message
Eric W. Biederman8b955b02006-10-04 02:16:55 -070084 *
85 * The irq number of the new irq or a negative error value is returned.
86 */
Eric W. Biederman43539c32006-11-08 17:44:57 -080087int __ht_create_irq(struct pci_dev *dev, int idx, ht_irq_update_t *update)
Eric W. Biederman8b955b02006-10-04 02:16:55 -070088{
89 struct ht_irq_cfg *cfg;
90 unsigned long flags;
91 u32 data;
92 int max_irq;
93 int pos;
Yinghai Lu1f3addc2008-09-05 10:03:37 -070094 int irq;
Yinghai Lu56b581e2009-04-27 18:02:46 -070095 int node;
Eric W. Biederman8b955b02006-10-04 02:16:55 -070096
Michael Ellerman120a50d2006-11-22 18:26:19 +110097 pos = pci_find_ht_capability(dev, HT_CAPTYPE_IRQ);
Eric W. Biederman8b955b02006-10-04 02:16:55 -070098 if (!pos)
99 return -EINVAL;
100
101 /* Verify the idx I want to use is in range */
102 spin_lock_irqsave(&ht_irq_lock, flags);
103 pci_write_config_byte(dev, pos + 2, 1);
104 pci_read_config_dword(dev, pos + 4, &data);
105 spin_unlock_irqrestore(&ht_irq_lock, flags);
106
107 max_irq = (data >> 16) & 0xff;
108 if ( idx > max_irq)
109 return -EINVAL;
110
111 cfg = kmalloc(sizeof(*cfg), GFP_KERNEL);
112 if (!cfg)
113 return -ENOMEM;
114
115 cfg->dev = dev;
Eric W. Biederman43539c32006-11-08 17:44:57 -0800116 cfg->update = update;
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700117 cfg->pos = pos;
118 cfg->idx = 0x10 + (idx * 2);
Eric W. Biedermanec683072006-11-08 17:44:57 -0800119 /* Initialize msg to a value that will never match the first write. */
120 cfg->msg.address_lo = 0xffffffff;
121 cfg->msg.address_hi = 0xffffffff;
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700122
Yinghai Lu56b581e2009-04-27 18:02:46 -0700123 node = dev_to_node(&dev->dev);
124 irq = create_irq_nr(0, node);
Thomas Gleixner2cc21ef2008-10-15 14:16:55 +0200125
Dean Nelsone65ef882008-09-05 09:07:20 -0500126 if (irq <= 0) {
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700127 kfree(cfg);
128 return -EBUSY;
129 }
Thomas Gleixnerdced35a2011-03-28 17:49:12 +0200130 irq_set_handler_data(irq, cfg);
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700131
132 if (arch_setup_ht_irq(irq, dev) < 0) {
133 ht_destroy_irq(irq);
134 return -EBUSY;
135 }
136
137 return irq;
138}
139
140/**
Eric W. Biederman43539c32006-11-08 17:44:57 -0800141 * ht_create_irq - create an irq and attach it to a device.
142 * @dev: The hypertransport device to find the irq capability on.
143 * @idx: Which of the possible irqs to attach to.
144 *
145 * ht_create_irq needs to be called for all hypertransport devices
146 * that generate irqs.
147 *
148 * The irq number of the new irq or a negative error value is returned.
149 */
150int ht_create_irq(struct pci_dev *dev, int idx)
151{
152 return __ht_create_irq(dev, idx, NULL);
153}
154
155/**
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700156 * ht_destroy_irq - destroy an irq created with ht_create_irq
Randy Dunlapcffb2fa2009-04-10 15:17:50 -0700157 * @irq: irq to be destroyed
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700158 *
159 * This reverses ht_create_irq removing the specified irq from
160 * existence. The irq should be free before this happens.
161 */
162void ht_destroy_irq(unsigned int irq)
163{
164 struct ht_irq_cfg *cfg;
165
Thomas Gleixnerdced35a2011-03-28 17:49:12 +0200166 cfg = irq_get_handler_data(irq);
167 irq_set_chip(irq, NULL);
168 irq_set_handler_data(irq, NULL);
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700169 destroy_irq(irq);
170
171 kfree(cfg);
172}
173
Eric W. Biederman43539c32006-11-08 17:44:57 -0800174EXPORT_SYMBOL(__ht_create_irq);
Eric W. Biederman8b955b02006-10-04 02:16:55 -0700175EXPORT_SYMBOL(ht_create_irq);
176EXPORT_SYMBOL(ht_destroy_irq);