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
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
|
/*
* Copyright (C) 2008 Ilya Yanok, Emcraft Systems
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/irq.h>
#include <linux/of_platform.h>
#include <linux/io.h>
/*
* The FPGA supports 9 interrupt sources, which can be routed to 3
* interrupt request lines of the MPIC. The line to be used can be
* specified through the third cell of FDT property "interrupts".
*/
#define SOCRATES_FPGA_NUM_IRQS 9
#define FPGA_PIC_IRQCFG (0x0)
#define FPGA_PIC_IRQMASK(n) (0x4 + 0x4 * (n))
#define SOCRATES_FPGA_IRQ_MASK ((1 << SOCRATES_FPGA_NUM_IRQS) - 1)
struct socrates_fpga_irq_info {
unsigned int irq_line;
int type;
};
/*
* Interrupt routing and type table
*
* IRQ_TYPE_NONE means the interrupt type is configurable,
* otherwise it's fixed to the specified value.
*/
static struct socrates_fpga_irq_info fpga_irqs[SOCRATES_FPGA_NUM_IRQS] = {
[0] = {0, IRQ_TYPE_NONE},
[1] = {0, IRQ_TYPE_LEVEL_HIGH},
[2] = {0, IRQ_TYPE_LEVEL_LOW},
[3] = {0, IRQ_TYPE_NONE},
[4] = {0, IRQ_TYPE_NONE},
[5] = {0, IRQ_TYPE_NONE},
[6] = {0, IRQ_TYPE_NONE},
[7] = {0, IRQ_TYPE_NONE},
[8] = {0, IRQ_TYPE_LEVEL_HIGH},
};
static DEFINE_RAW_SPINLOCK(socrates_fpga_pic_lock);
static void __iomem *socrates_fpga_pic_iobase;
static struct irq_host *socrates_fpga_pic_irq_host;
static unsigned int socrates_fpga_irqs[3];
static inline uint32_t socrates_fpga_pic_read(int reg)
{
return in_be32(socrates_fpga_pic_iobase + reg);
}
static inline void socrates_fpga_pic_write(int reg, uint32_t val)
{
out_be32(socrates_fpga_pic_iobase + reg, val);
}
static inline unsigned int socrates_fpga_pic_get_irq(unsigned int irq)
{
uint32_t cause;
unsigned long flags;
int i;
/* Check irq line routed to the MPIC */
for (i = 0; i < 3; i++) {
if (irq == socrates_fpga_irqs[i])
break;
}
if (i == 3)
return NO_IRQ;
raw_spin_lock_irqsave(&socrates_fpga_pic_lock, flags);
cause = socrates_fpga_pic_read(FPGA_PIC_IRQMASK(i));
raw_spin_unlock_irqrestore(&socrates_fpga_pic_lock, flags);
for (i = SOCRATES_FPGA_NUM_IRQS - 1; i >= 0; i--) {
if (cause >> (i + 16))
break;
}
return irq_linear_revmap(socrates_fpga_pic_irq_host,
(irq_hw_number_t)i);
}
void socrates_fpga_pic_cascade(unsigned int irq, struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
unsigned int cascade_irq;
/*
* See if we actually have an interrupt, call generic handling code if
* we do.
*/
cascade_irq = socrates_fpga_pic_get_irq(irq);
if (cascade_irq != NO_IRQ)
generic_handle_irq(cascade_irq);
chip->irq_eoi(&desc->irq_data);
}
static void socrates_fpga_pic_ack(struct irq_data *d)
{
unsigned long flags;
unsigned int irq_line, hwirq = irqd_to_hwirq(d);
uint32_t mask;
irq_line = fpga_irqs[hwirq].irq_line;
raw_spin_lock_irqsave(&socrates_fpga_pic_lock, flags);
mask = socrates_fpga_pic_read(FPGA_PIC_IRQMASK(irq_line))
& SOCRATES_FPGA_IRQ_MASK;
mask |= (1 << (hwirq + 16));
socrates_fpga_pic_write(FPGA_PIC_IRQMASK(irq_line), mask);
raw_spin_unlock_irqrestore(&socrates_fpga_pic_lock, flags);
}
static void socrates_fpga_pic_mask(struct irq_data *d)
{
unsigned long flags;
unsigned int hwirq = irqd_to_hwirq(d);
int irq_line;
u32 mask;
irq_line = fpga_irqs[hwirq].irq_line;
raw_spin_lock_irqsave(&socrates_fpga_pic_lock, flags);
mask = socrates_fpga_pic_read(FPGA_PIC_IRQMASK(irq_line))
& SOCRATES_FPGA_IRQ_MASK;
mask &= ~(1 << hwirq);
socrates_fpga_pic_write(FPGA_PIC_IRQMASK(irq_line), mask);
raw_spin_unlock_irqrestore(&socrates_fpga_pic_lock, flags);
}
static void socrates_fpga_pic_mask_ack(struct irq_data *d)
{
unsigned long flags;
unsigned int hwirq = irqd_to_hwirq(d);
int irq_line;
u32 mask;
irq_line = fpga_irqs[hwirq].irq_line;
raw_spin_lock_irqsave(&socrates_fpga_pic_lock, flags);
mask = socrates_fpga_pic_read(FPGA_PIC_IRQMASK(irq_line))
& SOCRATES_FPGA_IRQ_MASK;
mask &= ~(1 << hwirq);
mask |= (1 << (hwirq + 16));
socrates_fpga_pic_write(FPGA_PIC_IRQMASK(irq_line), mask);
raw_spin_unlock_irqrestore(&socrates_fpga_pic_lock, flags);
}
static void socrates_fpga_pic_unmask(struct irq_data *d)
{
unsigned long flags;
unsigned int hwirq = irqd_to_hwirq(d);
int irq_line;
u32 mask;
irq_line = fpga_irqs[hwirq].irq_line;
raw_spin_lock_irqsave(&socrates_fpga_pic_lock, flags);
mask = socrates_fpga_pic_read(FPGA_PIC_IRQMASK(irq_line))
& SOCRATES_FPGA_IRQ_MASK;
mask |= (1 << hwirq);
socrates_fpga_pic_write(FPGA_PIC_IRQMASK(irq_line), mask);
raw_spin_unlock_irqrestore(&socrates_fpga_pic_lock, flags);
}
static void socrates_fpga_pic_eoi(struct irq_data *d)
{
unsigned long flags;
unsigned int hwirq = irqd_to_hwirq(d);
int irq_line;
u32 mask;
irq_line = fpga_irqs[hwirq].irq_line;
raw_spin_lock_irqsave(&socrates_fpga_pic_lock, flags);
mask = socrates_fpga_pic_read(FPGA_PIC_IRQMASK(irq_line))
& SOCRATES_FPGA_IRQ_MASK;
mask |= (1 << (hwirq + 16));
socrates_fpga_pic_write(FPGA_PIC_IRQMASK(irq_line), mask);
raw_spin_unlock_irqrestore(&socrates_fpga_pic_lock, flags);
}
static int socrates_fpga_pic_set_type(struct irq_data *d,
unsigned int flow_type)
{
unsigned long flags;
unsigned int hwirq = irqd_to_hwirq(d);
int polarity;
u32 mask;
if (fpga_irqs[hwirq].type != IRQ_TYPE_NONE)
return -EINVAL;
switch (flow_type & IRQ_TYPE_SENSE_MASK) {
case IRQ_TYPE_LEVEL_HIGH:
polarity = 1;
break;
case IRQ_TYPE_LEVEL_LOW:
polarity = 0;
break;
default:
return -EINVAL;
}
raw_spin_lock_irqsave(&socrates_fpga_pic_lock, flags);
mask = socrates_fpga_pic_read(FPGA_PIC_IRQCFG);
if (polarity)
mask |= (1 << hwirq);
else
mask &= ~(1 << hwirq);
socrates_fpga_pic_write(FPGA_PIC_IRQCFG, mask);
raw_spin_unlock_irqrestore(&socrates_fpga_pic_lock, flags);
return 0;
}
static struct irq_chip socrates_fpga_pic_chip = {
.name = "FPGA-PIC",
.irq_ack = socrates_fpga_pic_ack,
.irq_mask = socrates_fpga_pic_mask,
.irq_mask_ack = socrates_fpga_pic_mask_ack,
.irq_unmask = socrates_fpga_pic_unmask,
.irq_eoi = socrates_fpga_pic_eoi,
.irq_set_type = socrates_fpga_pic_set_type,
};
static int socrates_fpga_pic_host_map(struct irq_host *h, unsigned int virq,
irq_hw_number_t hwirq)
{
/* All interrupts are LEVEL sensitive */
irq_set_status_flags(virq, IRQ_LEVEL);
irq_set_chip_and_handler(virq, &socrates_fpga_pic_chip,
handle_fasteoi_irq);
return 0;
}
static int socrates_fpga_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)
{
struct socrates_fpga_irq_info *fpga_irq = &fpga_irqs[intspec[0]];
*out_hwirq = intspec[0];
if (fpga_irq->type == IRQ_TYPE_NONE) {
/* type is configurable */
if (intspec[1] != IRQ_TYPE_LEVEL_LOW &&
intspec[1] != IRQ_TYPE_LEVEL_HIGH) {
pr_warning("FPGA PIC: invalid irq type, "
"setting default active low\n");
*out_flags = IRQ_TYPE_LEVEL_LOW;
} else {
*out_flags = intspec[1];
}
} else {
/* type is fixed */
*out_flags = fpga_irq->type;
}
/* Use specified interrupt routing */
if (intspec[2] <= 2)
fpga_irq->irq_line = intspec[2];
else
pr_warning("FPGA PIC: invalid irq routing\n");
return 0;
}
static struct irq_host_ops socrates_fpga_pic_host_ops = {
.map = socrates_fpga_pic_host_map,
.xlate = socrates_fpga_pic_host_xlate,
};
void socrates_fpga_pic_init(struct device_node *pic)
{
unsigned long flags;
int i;
/* Setup an irq_host structure */
socrates_fpga_pic_irq_host = irq_alloc_host(pic, IRQ_HOST_MAP_LINEAR,
SOCRATES_FPGA_NUM_IRQS, &socrates_fpga_pic_host_ops,
SOCRATES_FPGA_NUM_IRQS);
if (socrates_fpga_pic_irq_host == NULL) {
pr_err("FPGA PIC: Unable to allocate host\n");
return;
}
for (i = 0; i < 3; i++) {
socrates_fpga_irqs[i] = irq_of_parse_and_map(pic, i);
if (socrates_fpga_irqs[i] == NO_IRQ) {
pr_warning("FPGA PIC: can't get irq%d.\n", i);
continue;
}
irq_set_chained_handler(socrates_fpga_irqs[i],
socrates_fpga_pic_cascade);
}
socrates_fpga_pic_iobase = of_iomap(pic, 0);
raw_spin_lock_irqsave(&socrates_fpga_pic_lock, flags);
socrates_fpga_pic_write(FPGA_PIC_IRQMASK(0),
SOCRATES_FPGA_IRQ_MASK << 16);
socrates_fpga_pic_write(FPGA_PIC_IRQMASK(1),
SOCRATES_FPGA_IRQ_MASK << 16);
socrates_fpga_pic_write(FPGA_PIC_IRQMASK(2),
SOCRATES_FPGA_IRQ_MASK << 16);
raw_spin_unlock_irqrestore(&socrates_fpga_pic_lock, flags);
pr_info("FPGA PIC: Setting up Socrates FPGA PIC\n");
}
|
