3 * Purpose: Hypertransport Interrupt Capability
5 * Copyright (C) 2006 Linux Networx
6 * Copyright (C) Eric Biederman <ebiederman@lnxi.com>
10 #include <linux/pci.h>
11 #include <linux/spinlock.h>
12 #include <linux/slab.h>
13 #include <linux/gfp.h>
14 #include <linux/htirq.h>
16 /* Global ht irq lock.
18 * This is needed to serialize access to the data port in hypertransport
21 * With multiple simultaneous hypertransport irq devices it might pay
22 * to make this more fine grained. But start with simple, stupid, and correct.
24 static DEFINE_SPINLOCK(ht_irq_lock);
28 /* Update callback used to cope with buggy hardware */
29 ht_irq_update_t *update;
32 struct ht_irq_msg msg;
36 void write_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg)
38 struct ht_irq_cfg *cfg = get_irq_data(irq);
40 spin_lock_irqsave(&ht_irq_lock, flags);
41 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);
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);
50 cfg->update(cfg->dev, irq, msg);
51 spin_unlock_irqrestore(&ht_irq_lock, flags);
55 void fetch_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg)
57 struct ht_irq_cfg *cfg = get_irq_data(irq);
61 void mask_ht_irq(unsigned int irq)
63 struct ht_irq_cfg *cfg;
64 struct ht_irq_msg msg;
66 cfg = get_irq_data(irq);
70 write_ht_irq_msg(irq, &msg);
73 void unmask_ht_irq(unsigned int irq)
75 struct ht_irq_cfg *cfg;
76 struct ht_irq_msg msg;
78 cfg = get_irq_data(irq);
82 write_ht_irq_msg(irq, &msg);
85 static unsigned int build_irq_for_pci_dev(struct pci_dev *dev)
89 irq = dev->bus->number;
98 * __ht_create_irq - create an irq and attach it to a device.
99 * @dev: The hypertransport device to find the irq capability on.
100 * @idx: Which of the possible irqs to attach to.
101 * @update: Function to be called when changing the htirq message
103 * The irq number of the new irq or a negative error value is returned.
105 int __ht_create_irq(struct pci_dev *dev, int idx, ht_irq_update_t *update)
107 struct ht_irq_cfg *cfg;
113 unsigned int irq_want;
115 pos = pci_find_ht_capability(dev, HT_CAPTYPE_IRQ);
119 /* Verify the idx I want to use is in range */
120 spin_lock_irqsave(&ht_irq_lock, flags);
121 pci_write_config_byte(dev, pos + 2, 1);
122 pci_read_config_dword(dev, pos + 4, &data);
123 spin_unlock_irqrestore(&ht_irq_lock, flags);
125 max_irq = (data >> 16) & 0xff;
129 cfg = kmalloc(sizeof(*cfg), GFP_KERNEL);
134 cfg->update = update;
136 cfg->idx = 0x10 + (idx * 2);
137 /* Initialize msg to a value that will never match the first write. */
138 cfg->msg.address_lo = 0xffffffff;
139 cfg->msg.address_hi = 0xffffffff;
141 irq_want= build_irq_for_pci_dev(dev);
142 #ifdef CONFIG_HAVE_SPARSE_IRQ
143 irq = create_irq_nr(irq_want + idx);
151 set_irq_data(irq, cfg);
153 if (arch_setup_ht_irq(irq, dev) < 0) {
162 * ht_create_irq - create an irq and attach it to a device.
163 * @dev: The hypertransport device to find the irq capability on.
164 * @idx: Which of the possible irqs to attach to.
166 * ht_create_irq needs to be called for all hypertransport devices
167 * that generate irqs.
169 * The irq number of the new irq or a negative error value is returned.
171 int ht_create_irq(struct pci_dev *dev, int idx)
173 return __ht_create_irq(dev, idx, NULL);
177 * ht_destroy_irq - destroy an irq created with ht_create_irq
179 * This reverses ht_create_irq removing the specified irq from
180 * existence. The irq should be free before this happens.
182 void ht_destroy_irq(unsigned int irq)
184 struct ht_irq_cfg *cfg;
186 cfg = get_irq_data(irq);
187 set_irq_chip(irq, NULL);
188 set_irq_data(irq, NULL);
194 EXPORT_SYMBOL(__ht_create_irq);
195 EXPORT_SYMBOL(ht_create_irq);
196 EXPORT_SYMBOL(ht_destroy_irq);