[linux-2.6-block.git] / drivers / pci / htirq.c

/*
 * 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/slab.h>
#include <linux/gfp.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;
	unsigned pos;
	unsigned idx;
};

void write_ht_irq_low(unsigned int irq, u32 data)
{
	struct ht_irq_cfg *cfg = get_irq_data(irq);
	unsigned long flags;
	spin_lock_irqsave(&ht_irq_lock, flags);
	pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx);
	pci_write_config_dword(cfg->dev, cfg->pos + 4, data);
	spin_unlock_irqrestore(&ht_irq_lock, flags);
}

void write_ht_irq_high(unsigned int irq, u32 data)
{
	struct ht_irq_cfg *cfg = get_irq_data(irq);
	unsigned long flags;
	spin_lock_irqsave(&ht_irq_lock, flags);
	pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx + 1);
	pci_write_config_dword(cfg->dev, cfg->pos + 4, data);
	spin_unlock_irqrestore(&ht_irq_lock, flags);
}

u32 read_ht_irq_low(unsigned int irq)
{
	struct ht_irq_cfg *cfg = get_irq_data(irq);
	unsigned long flags;
	u32 data;
	spin_lock_irqsave(&ht_irq_lock, flags);
	pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx);
	pci_read_config_dword(cfg->dev, cfg->pos + 4, &data);
	spin_unlock_irqrestore(&ht_irq_lock, flags);
	return data;
}

u32 read_ht_irq_high(unsigned int irq)
{
	struct ht_irq_cfg *cfg = get_irq_data(irq);
	unsigned long flags;
	u32 data;
	spin_lock_irqsave(&ht_irq_lock, flags);
	pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx + 1);
	pci_read_config_dword(cfg->dev, cfg->pos + 4, &data);
	spin_unlock_irqrestore(&ht_irq_lock, flags);
	return data;
}

void mask_ht_irq(unsigned int irq)
{
	struct ht_irq_cfg *cfg;
	unsigned long flags;
	u32 data;

	cfg = get_irq_data(irq);

	spin_lock_irqsave(&ht_irq_lock, flags);
	pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx);
	pci_read_config_dword(cfg->dev, cfg->pos + 4, &data);
	data |= 1;
	pci_write_config_dword(cfg->dev, cfg->pos + 4, data);
	spin_unlock_irqrestore(&ht_irq_lock, flags);
}

void unmask_ht_irq(unsigned int irq)
{
	struct ht_irq_cfg *cfg;
	unsigned long flags;
	u32 data;

	cfg = get_irq_data(irq);

	spin_lock_irqsave(&ht_irq_lock, flags);
	pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx);
	pci_read_config_dword(cfg->dev, cfg->pos + 4, &data);
	data &= ~1;
	pci_write_config_dword(cfg->dev, cfg->pos + 4, data);
	spin_unlock_irqrestore(&ht_irq_lock, flags);
}

/**
 * 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 is 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)
{
	struct ht_irq_cfg *cfg;
	unsigned long flags;
	u32 data;
	int max_irq;
	int pos;
	int irq;

	pos = pci_find_capability(dev, PCI_CAP_ID_HT);
	while (pos) {
		u8 subtype;
		pci_read_config_byte(dev, pos + 3, &subtype);
		if (subtype == HT_CAPTYPE_IRQ)
			break;
		pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_HT);
	}
	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->pos = pos;
	cfg->idx = 0x10 + (idx * 2);

	irq = create_irq();
	if (irq < 0) {
		kfree(cfg);
		return -EBUSY;
	}
	set_irq_data(irq, cfg);

	if (arch_setup_ht_irq(irq, dev) < 0) {
		ht_destroy_irq(irq);
		return -EBUSY;
	}

	return irq;
}

/**
 * ht_destroy_irq - destroy an irq created with ht_create_irq
 *
 * 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 = get_irq_data(irq);
	set_irq_chip(irq, NULL);
	set_irq_data(irq, NULL);
	destroy_irq(irq);

	kfree(cfg);
}

EXPORT_SYMBOL(ht_create_irq);
EXPORT_SYMBOL(ht_destroy_irq);
Commit	Line	Data
8b955b0d EB	1	/*
	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>
	13	#include <linux/gfp.h>
	14
	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	*/
	23	static DEFINE_SPINLOCK(ht_irq_lock);
	24
	25	struct ht_irq_cfg {
	26	struct pci_dev *dev;
	27	unsigned pos;
	28	unsigned idx;
	29	};
	30
	31	void write_ht_irq_low(unsigned int irq, u32 data)
	32	{
	33	struct ht_irq_cfg *cfg = get_irq_data(irq);
	34	unsigned long flags;
	35	spin_lock_irqsave(&ht_irq_lock, flags);
	36	pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx);
	37	pci_write_config_dword(cfg->dev, cfg->pos + 4, data);
	38	spin_unlock_irqrestore(&ht_irq_lock, flags);
	39	}
	40
	41	void write_ht_irq_high(unsigned int irq, u32 data)
	42	{
	43	struct ht_irq_cfg *cfg = get_irq_data(irq);
	44	unsigned long flags;
	45	spin_lock_irqsave(&ht_irq_lock, flags);
	46	pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx + 1);
	47	pci_write_config_dword(cfg->dev, cfg->pos + 4, data);
	48	spin_unlock_irqrestore(&ht_irq_lock, flags);
	49	}
	50
	51	u32 read_ht_irq_low(unsigned int irq)
	52	{
	53	struct ht_irq_cfg *cfg = get_irq_data(irq);
	54	unsigned long flags;
	55	u32 data;
	56	spin_lock_irqsave(&ht_irq_lock, flags);
	57	pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx);
	58	pci_read_config_dword(cfg->dev, cfg->pos + 4, &data);
	59	spin_unlock_irqrestore(&ht_irq_lock, flags);
	60	return data;
	61	}
	62
	63	u32 read_ht_irq_high(unsigned int irq)
	64	{
65	struct ht_irq_cfg *cfg = get_irq_data(irq);
66	unsigned long flags;
67	u32 data;
68	spin_lock_irqsave(&ht_irq_lock, flags);
69	pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx + 1);
70	pci_read_config_dword(cfg->dev, cfg->pos + 4, &data);
71	spin_unlock_irqrestore(&ht_irq_lock, flags);
72	return data;
73	}
74
75	void mask_ht_irq(unsigned int irq)
76	{
77	struct ht_irq_cfg *cfg;
78	unsigned long flags;
79	u32 data;
80
81	cfg = get_irq_data(irq);
82
83	spin_lock_irqsave(&ht_irq_lock, flags);
84	pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx);
85	pci_read_config_dword(cfg->dev, cfg->pos + 4, &data);
86	data \|= 1;
87	pci_write_config_dword(cfg->dev, cfg->pos + 4, data);
88	spin_unlock_irqrestore(&ht_irq_lock, flags);
89	}
90
91	void unmask_ht_irq(unsigned int irq)
92	{
93	struct ht_irq_cfg *cfg;
94	unsigned long flags;
95	u32 data;
96
97	cfg = get_irq_data(irq);
98
99	spin_lock_irqsave(&ht_irq_lock, flags);
100	pci_write_config_byte(cfg->dev, cfg->pos + 2, cfg->idx);
101	pci_read_config_dword(cfg->dev, cfg->pos + 4, &data);
102	data &= ~1;
103	pci_write_config_dword(cfg->dev, cfg->pos + 4, data);
104	spin_unlock_irqrestore(&ht_irq_lock, flags);
105	}
106
107	/**
108	* ht_create_irq - create an irq and attach it to a device.
109	* @dev: The hypertransport device to find the irq capability on.
110	* @idx: Which of the possible irqs to attach to.
111	*
112	* ht_create_irq is needs to be called for all hypertransport devices
113	* that generate irqs.
114	*
115	* The irq number of the new irq or a negative error value is returned.
116	*/
117	int ht_create_irq(struct pci_dev *dev, int idx)
118	{
119	struct ht_irq_cfg *cfg;
120	unsigned long flags;
121	u32 data;
122	int max_irq;
123	int pos;
124	int irq;
125
126	pos = pci_find_capability(dev, PCI_CAP_ID_HT);
127	while (pos) {
128	u8 subtype;
129	pci_read_config_byte(dev, pos + 3, &subtype);
130	if (subtype == HT_CAPTYPE_IRQ)
131	break;
132	pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_HT);
133	}
134	if (!pos)
135	return -EINVAL;
136
137	/* Verify the idx I want to use is in range */
138	spin_lock_irqsave(&ht_irq_lock, flags);
139	pci_write_config_byte(dev, pos + 2, 1);
140	pci_read_config_dword(dev, pos + 4, &data);
141	spin_unlock_irqrestore(&ht_irq_lock, flags);
142
143	max_irq = (data >> 16) & 0xff;
144	if ( idx > max_irq)
145	return -EINVAL;
146
147	cfg = kmalloc(sizeof(*cfg), GFP_KERNEL);
148	if (!cfg)
149	return -ENOMEM;
150
151	cfg->dev = dev;
152	cfg->pos = pos;
153	cfg->idx = 0x10 + (idx * 2);
154
155	irq = create_irq();
156	if (irq < 0) {
157	kfree(cfg);
158	return -EBUSY;
159	}
160	set_irq_data(irq, cfg);
161
162	if (arch_setup_ht_irq(irq, dev) < 0) {
163	ht_destroy_irq(irq);
164	return -EBUSY;
165	}
166
167	return irq;
168	}
169
170	/**
171	* ht_destroy_irq - destroy an irq created with ht_create_irq
172	*
173	* This reverses ht_create_irq removing the specified irq from
174	* existence. The irq should be free before this happens.
175	*/
176	void ht_destroy_irq(unsigned int irq)
177	{
178	struct ht_irq_cfg *cfg;
179
180	cfg = get_irq_data(irq);
181	set_irq_chip(irq, NULL);
182	set_irq_data(irq, NULL);
183	destroy_irq(irq);
184
185	kfree(cfg);
186	}
187
188	EXPORT_SYMBOL(ht_create_irq);
189	EXPORT_SYMBOL(ht_destroy_irq);