summaryrefslogtreecommitdiff
path: root/arch/powerpc/platforms/cell/beat_interrupt.c
blob: 55015e1f69398f6f306c596ea1b877508a7410d4 (plain)
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
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
/*
 * Celleb/Beat Interrupt controller
 *
 * (C) Copyright 2006-2007 TOSHIBA CORPORATION
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/percpu.h>
#include <linux/types.h>

#include <asm/machdep.h>

#include "beat_interrupt.h"
#include "beat_wrapper.h"

#define	MAX_IRQS	NR_IRQS
static DEFINE_RAW_SPINLOCK(beatic_irq_mask_lock);
static uint64_t	beatic_irq_mask_enable[(MAX_IRQS+255)/64];
static uint64_t	beatic_irq_mask_ack[(MAX_IRQS+255)/64];

static struct irq_host *beatic_host;

/*
 * In this implementation, "virq" == "IRQ plug number",
 * "(irq_hw_number_t)hwirq" == "IRQ outlet number".
 */

/* assumption: locked */
static inline void beatic_update_irq_mask(unsigned int irq_plug)
{
	int off;
	unsigned long masks[4];

	off = (irq_plug / 256) * 4;
	masks[0] = beatic_irq_mask_enable[off + 0]
		& beatic_irq_mask_ack[off + 0];
	masks[1] = beatic_irq_mask_enable[off + 1]
		& beatic_irq_mask_ack[off + 1];
	masks[2] = beatic_irq_mask_enable[off + 2]
		& beatic_irq_mask_ack[off + 2];
	masks[3] = beatic_irq_mask_enable[off + 3]
		& beatic_irq_mask_ack[off + 3];
	if (beat_set_interrupt_mask(irq_plug&~255UL,
		masks[0], masks[1], masks[2], masks[3]) != 0)
		panic("Failed to set mask IRQ!");
}

static void beatic_mask_irq(struct irq_data *d)
{
	unsigned long flags;

	raw_spin_lock_irqsave(&beatic_irq_mask_lock, flags);
	beatic_irq_mask_enable[d->irq/64] &= ~(1UL << (63 - (d->irq%64)));
	beatic_update_irq_mask(d->irq);
	raw_spin_unlock_irqrestore(&beatic_irq_mask_lock, flags);
}

static void beatic_unmask_irq(struct irq_data *d)
{
	unsigned long flags;

	raw_spin_lock_irqsave(&beatic_irq_mask_lock, flags);
	beatic_irq_mask_enable[d->irq/64] |= 1UL << (63 - (d->irq%64));
	beatic_update_irq_mask(d->irq);
	raw_spin_unlock_irqrestore(&beatic_irq_mask_lock, flags);
}

static void beatic_ack_irq(struct irq_data *d)
{
	unsigned long flags;

	raw_spin_lock_irqsave(&beatic_irq_mask_lock, flags);
	beatic_irq_mask_ack[d->irq/64] &= ~(1UL << (63 - (d->irq%64)));
	beatic_update_irq_mask(d->irq);
	raw_spin_unlock_irqrestore(&beatic_irq_mask_lock, flags);
}

static void beatic_end_irq(struct irq_data *d)
{
	s64 err;
	unsigned long flags;

	err = beat_downcount_of_interrupt(d->irq);
	if (err != 0) {
		if ((err & 0xFFFFFFFF) != 0xFFFFFFF5) /* -11: wrong state */
			panic("Failed to downcount IRQ! Error = %16llx", err);

		printk(KERN_ERR "IRQ over-downcounted, plug %d\n", d->irq);
	}
	raw_spin_lock_irqsave(&beatic_irq_mask_lock, flags);
	beatic_irq_mask_ack[d->irq/64] |= 1UL << (63 - (d->irq%64));
	beatic_update_irq_mask(d->irq);
	raw_spin_unlock_irqrestore(&beatic_irq_mask_lock, flags);
}

static struct irq_chip beatic_pic = {
	.name = "CELL-BEAT",
	.irq_unmask = beatic_unmask_irq,
	.irq_mask = beatic_mask_irq,
	.irq_eoi = beatic_end_irq,
};

/*
 * Dispose binding hardware IRQ number (hw) and Virtuql IRQ number (virq),
 * update flags.
 *
 * Note that the number (virq) is already assigned at upper layer.
 */
static void beatic_pic_host_unmap(struct irq_host *h, unsigned int virq)
{
	beat_destruct_irq_plug(virq);
}

/*
 * Create or update binding hardware IRQ number (hw) and Virtuql
 * IRQ number (virq). This is called only once for a given mapping.
 *
 * Note that the number (virq) is already assigned at upper layer.
 */
static int beatic_pic_host_map(struct irq_host *h, unsigned int virq,
			       irq_hw_number_t hw)
{
	int64_t	err;

	err = beat_construct_and_connect_irq_plug(virq, hw);
	if (err < 0)
		return -EIO;

	irq_set_status_flags(virq, IRQ_LEVEL);
	irq_set_chip_and_handler(virq, &beatic_pic, handle_fasteoi_irq);
	return 0;
}

/*
 * Translate device-tree interrupt spec to irq_hw_number_t style (ulong),
 * to pass away to irq_create_mapping().
 *
 * Called from irq_create_of_mapping() only.
 * Note: We have only 1 entry to translate.
 */
static int beatic_pic_host_xlate(struct irq_host *h, struct device_node *ct,
				 const u32 *intspec, unsigned int intsize,
				 irq_hw_number_t *out_hwirq,
				 unsigned int *out_flags)
{
	const u64 *intspec2 = (const u64 *)intspec;

	*out_hwirq = *intspec2;
	*out_flags |= IRQ_TYPE_LEVEL_LOW;
	return 0;
}

static int beatic_pic_host_match(struct irq_host *h, struct device_node *np)
{
	/* Match all */
	return 1;
}

static struct irq_host_ops beatic_pic_host_ops = {
	.map = beatic_pic_host_map,
	.unmap = beatic_pic_host_unmap,
	.xlate = beatic_pic_host_xlate,
	.match = beatic_pic_host_match,
};

/*
 * Get an IRQ number
 * Note: returns VIRQ
 */
static inline unsigned int beatic_get_irq_plug(void)
{
	int i;
	uint64_t	pending[4], ub;

	for (i = 0; i < MAX_IRQS; i += 256) {
		beat_detect_pending_interrupts(i, pending);
		__asm__ ("cntlzd %0,%1":"=r"(ub):
			"r"(pending[0] & beatic_irq_mask_enable[i/64+0]
				       & beatic_irq_mask_ack[i/64+0]));
		if (ub != 64)
			return i + ub + 0;
		__asm__ ("cntlzd %0,%1":"=r"(ub):
			"r"(pending[1] & beatic_irq_mask_enable[i/64+1]
				       & beatic_irq_mask_ack[i/64+1]));
		if (ub != 64)
			return i + ub + 64;
		__asm__ ("cntlzd %0,%1":"=r"(ub):
			"r"(pending[2] & beatic_irq_mask_enable[i/64+2]
				       & beatic_irq_mask_ack[i/64+2]));
		if (ub != 64)
			return i + ub + 128;
		__asm__ ("cntlzd %0,%1":"=r"(ub):
			"r"(pending[3] & beatic_irq_mask_enable[i/64+3]
				       & beatic_irq_mask_ack[i/64+3]));
		if (ub != 64)
			return i + ub + 192;
	}

	return NO_IRQ;
}
unsigned int beatic_get_irq(void)
{
	unsigned int ret;

	ret = beatic_get_irq_plug();
	if (ret != NO_IRQ)
		beatic_ack_irq(irq_get_irq_data(ret));
	return ret;
}

/*
 */
void __init beatic_init_IRQ(void)
{
	int	i;

	memset(beatic_irq_mask_enable, 0, sizeof(beatic_irq_mask_enable));
	memset(beatic_irq_mask_ack, 255, sizeof(beatic_irq_mask_ack));
	for (i = 0; i < MAX_IRQS; i += 256)
		beat_set_interrupt_mask(i, 0L, 0L, 0L, 0L);

	/* Set out get_irq function */
	ppc_md.get_irq = beatic_get_irq;

	/* Allocate an irq host */
	beatic_host = irq_alloc_host(NULL, IRQ_HOST_MAP_NOMAP, 0,
				     &beatic_pic_host_ops,
					 0);
	BUG_ON(beatic_host == NULL);
	irq_set_default_host(beatic_host);
}

void beatic_deinit_IRQ(void)
{
	int	i;

	for (i = 1; i < NR_IRQS; i++)
		beat_destruct_irq_plug(i);
}