xref: /openbmc/linux/drivers/soc/fsl/qe/qe_ic.c (revision f3539c12)
1 /*
2  * arch/powerpc/sysdev/qe_lib/qe_ic.c
3  *
4  * Copyright (C) 2006 Freescale Semiconductor, Inc.  All rights reserved.
5  *
6  * Author: Li Yang <leoli@freescale.com>
7  * Based on code from Shlomi Gridish <gridish@freescale.com>
8  *
9  * QUICC ENGINE Interrupt Controller
10  *
11  * This program is free software; you can redistribute  it and/or modify it
12  * under  the terms of  the GNU General  Public License as published by the
13  * Free Software Foundation;  either version 2 of the  License, or (at your
14  * option) any later version.
15  */
16 
17 #include <linux/of_irq.h>
18 #include <linux/of_address.h>
19 #include <linux/kernel.h>
20 #include <linux/init.h>
21 #include <linux/errno.h>
22 #include <linux/reboot.h>
23 #include <linux/slab.h>
24 #include <linux/stddef.h>
25 #include <linux/sched.h>
26 #include <linux/signal.h>
27 #include <linux/device.h>
28 #include <linux/spinlock.h>
29 #include <asm/irq.h>
30 #include <asm/io.h>
31 #include <soc/fsl/qe/qe_ic.h>
32 
33 #include "qe_ic.h"
34 
35 static DEFINE_RAW_SPINLOCK(qe_ic_lock);
36 
37 static struct qe_ic_info qe_ic_info[] = {
38 	[1] = {
39 	       .mask = 0x00008000,
40 	       .mask_reg = QEIC_CIMR,
41 	       .pri_code = 0,
42 	       .pri_reg = QEIC_CIPWCC,
43 	       },
44 	[2] = {
45 	       .mask = 0x00004000,
46 	       .mask_reg = QEIC_CIMR,
47 	       .pri_code = 1,
48 	       .pri_reg = QEIC_CIPWCC,
49 	       },
50 	[3] = {
51 	       .mask = 0x00002000,
52 	       .mask_reg = QEIC_CIMR,
53 	       .pri_code = 2,
54 	       .pri_reg = QEIC_CIPWCC,
55 	       },
56 	[10] = {
57 		.mask = 0x00000040,
58 		.mask_reg = QEIC_CIMR,
59 		.pri_code = 1,
60 		.pri_reg = QEIC_CIPZCC,
61 		},
62 	[11] = {
63 		.mask = 0x00000020,
64 		.mask_reg = QEIC_CIMR,
65 		.pri_code = 2,
66 		.pri_reg = QEIC_CIPZCC,
67 		},
68 	[12] = {
69 		.mask = 0x00000010,
70 		.mask_reg = QEIC_CIMR,
71 		.pri_code = 3,
72 		.pri_reg = QEIC_CIPZCC,
73 		},
74 	[13] = {
75 		.mask = 0x00000008,
76 		.mask_reg = QEIC_CIMR,
77 		.pri_code = 4,
78 		.pri_reg = QEIC_CIPZCC,
79 		},
80 	[14] = {
81 		.mask = 0x00000004,
82 		.mask_reg = QEIC_CIMR,
83 		.pri_code = 5,
84 		.pri_reg = QEIC_CIPZCC,
85 		},
86 	[15] = {
87 		.mask = 0x00000002,
88 		.mask_reg = QEIC_CIMR,
89 		.pri_code = 6,
90 		.pri_reg = QEIC_CIPZCC,
91 		},
92 	[20] = {
93 		.mask = 0x10000000,
94 		.mask_reg = QEIC_CRIMR,
95 		.pri_code = 3,
96 		.pri_reg = QEIC_CIPRTA,
97 		},
98 	[25] = {
99 		.mask = 0x00800000,
100 		.mask_reg = QEIC_CRIMR,
101 		.pri_code = 0,
102 		.pri_reg = QEIC_CIPRTB,
103 		},
104 	[26] = {
105 		.mask = 0x00400000,
106 		.mask_reg = QEIC_CRIMR,
107 		.pri_code = 1,
108 		.pri_reg = QEIC_CIPRTB,
109 		},
110 	[27] = {
111 		.mask = 0x00200000,
112 		.mask_reg = QEIC_CRIMR,
113 		.pri_code = 2,
114 		.pri_reg = QEIC_CIPRTB,
115 		},
116 	[28] = {
117 		.mask = 0x00100000,
118 		.mask_reg = QEIC_CRIMR,
119 		.pri_code = 3,
120 		.pri_reg = QEIC_CIPRTB,
121 		},
122 	[32] = {
123 		.mask = 0x80000000,
124 		.mask_reg = QEIC_CIMR,
125 		.pri_code = 0,
126 		.pri_reg = QEIC_CIPXCC,
127 		},
128 	[33] = {
129 		.mask = 0x40000000,
130 		.mask_reg = QEIC_CIMR,
131 		.pri_code = 1,
132 		.pri_reg = QEIC_CIPXCC,
133 		},
134 	[34] = {
135 		.mask = 0x20000000,
136 		.mask_reg = QEIC_CIMR,
137 		.pri_code = 2,
138 		.pri_reg = QEIC_CIPXCC,
139 		},
140 	[35] = {
141 		.mask = 0x10000000,
142 		.mask_reg = QEIC_CIMR,
143 		.pri_code = 3,
144 		.pri_reg = QEIC_CIPXCC,
145 		},
146 	[36] = {
147 		.mask = 0x08000000,
148 		.mask_reg = QEIC_CIMR,
149 		.pri_code = 4,
150 		.pri_reg = QEIC_CIPXCC,
151 		},
152 	[40] = {
153 		.mask = 0x00800000,
154 		.mask_reg = QEIC_CIMR,
155 		.pri_code = 0,
156 		.pri_reg = QEIC_CIPYCC,
157 		},
158 	[41] = {
159 		.mask = 0x00400000,
160 		.mask_reg = QEIC_CIMR,
161 		.pri_code = 1,
162 		.pri_reg = QEIC_CIPYCC,
163 		},
164 	[42] = {
165 		.mask = 0x00200000,
166 		.mask_reg = QEIC_CIMR,
167 		.pri_code = 2,
168 		.pri_reg = QEIC_CIPYCC,
169 		},
170 	[43] = {
171 		.mask = 0x00100000,
172 		.mask_reg = QEIC_CIMR,
173 		.pri_code = 3,
174 		.pri_reg = QEIC_CIPYCC,
175 		},
176 };
177 
178 static inline u32 qe_ic_read(volatile __be32  __iomem * base, unsigned int reg)
179 {
180 	return in_be32(base + (reg >> 2));
181 }
182 
183 static inline void qe_ic_write(volatile __be32  __iomem * base, unsigned int reg,
184 			       u32 value)
185 {
186 	out_be32(base + (reg >> 2), value);
187 }
188 
189 static inline struct qe_ic *qe_ic_from_irq(unsigned int virq)
190 {
191 	return irq_get_chip_data(virq);
192 }
193 
194 static inline struct qe_ic *qe_ic_from_irq_data(struct irq_data *d)
195 {
196 	return irq_data_get_irq_chip_data(d);
197 }
198 
199 static void qe_ic_unmask_irq(struct irq_data *d)
200 {
201 	struct qe_ic *qe_ic = qe_ic_from_irq_data(d);
202 	unsigned int src = irqd_to_hwirq(d);
203 	unsigned long flags;
204 	u32 temp;
205 
206 	raw_spin_lock_irqsave(&qe_ic_lock, flags);
207 
208 	temp = qe_ic_read(qe_ic->regs, qe_ic_info[src].mask_reg);
209 	qe_ic_write(qe_ic->regs, qe_ic_info[src].mask_reg,
210 		    temp | qe_ic_info[src].mask);
211 
212 	raw_spin_unlock_irqrestore(&qe_ic_lock, flags);
213 }
214 
215 static void qe_ic_mask_irq(struct irq_data *d)
216 {
217 	struct qe_ic *qe_ic = qe_ic_from_irq_data(d);
218 	unsigned int src = irqd_to_hwirq(d);
219 	unsigned long flags;
220 	u32 temp;
221 
222 	raw_spin_lock_irqsave(&qe_ic_lock, flags);
223 
224 	temp = qe_ic_read(qe_ic->regs, qe_ic_info[src].mask_reg);
225 	qe_ic_write(qe_ic->regs, qe_ic_info[src].mask_reg,
226 		    temp & ~qe_ic_info[src].mask);
227 
228 	/* Flush the above write before enabling interrupts; otherwise,
229 	 * spurious interrupts will sometimes happen.  To be 100% sure
230 	 * that the write has reached the device before interrupts are
231 	 * enabled, the mask register would have to be read back; however,
232 	 * this is not required for correctness, only to avoid wasting
233 	 * time on a large number of spurious interrupts.  In testing,
234 	 * a sync reduced the observed spurious interrupts to zero.
235 	 */
236 	mb();
237 
238 	raw_spin_unlock_irqrestore(&qe_ic_lock, flags);
239 }
240 
241 static struct irq_chip qe_ic_irq_chip = {
242 	.name = "QEIC",
243 	.irq_unmask = qe_ic_unmask_irq,
244 	.irq_mask = qe_ic_mask_irq,
245 	.irq_mask_ack = qe_ic_mask_irq,
246 };
247 
248 static int qe_ic_host_match(struct irq_domain *h, struct device_node *node,
249 			    enum irq_domain_bus_token bus_token)
250 {
251 	/* Exact match, unless qe_ic node is NULL */
252 	struct device_node *of_node = irq_domain_get_of_node(h);
253 	return of_node == NULL || of_node == node;
254 }
255 
256 static int qe_ic_host_map(struct irq_domain *h, unsigned int virq,
257 			  irq_hw_number_t hw)
258 {
259 	struct qe_ic *qe_ic = h->host_data;
260 	struct irq_chip *chip;
261 
262 	if (hw >= ARRAY_SIZE(qe_ic_info)) {
263 		pr_err("%s: Invalid hw irq number for QEIC\n", __func__);
264 		return -EINVAL;
265 	}
266 
267 	if (qe_ic_info[hw].mask == 0) {
268 		printk(KERN_ERR "Can't map reserved IRQ\n");
269 		return -EINVAL;
270 	}
271 	/* Default chip */
272 	chip = &qe_ic->hc_irq;
273 
274 	irq_set_chip_data(virq, qe_ic);
275 	irq_set_status_flags(virq, IRQ_LEVEL);
276 
277 	irq_set_chip_and_handler(virq, chip, handle_level_irq);
278 
279 	return 0;
280 }
281 
282 static const struct irq_domain_ops qe_ic_host_ops = {
283 	.match = qe_ic_host_match,
284 	.map = qe_ic_host_map,
285 	.xlate = irq_domain_xlate_onetwocell,
286 };
287 
288 /* Return an interrupt vector or NO_IRQ if no interrupt is pending. */
289 unsigned int qe_ic_get_low_irq(struct qe_ic *qe_ic)
290 {
291 	int irq;
292 
293 	BUG_ON(qe_ic == NULL);
294 
295 	/* get the interrupt source vector. */
296 	irq = qe_ic_read(qe_ic->regs, QEIC_CIVEC) >> 26;
297 
298 	if (irq == 0)
299 		return NO_IRQ;
300 
301 	return irq_linear_revmap(qe_ic->irqhost, irq);
302 }
303 
304 /* Return an interrupt vector or NO_IRQ if no interrupt is pending. */
305 unsigned int qe_ic_get_high_irq(struct qe_ic *qe_ic)
306 {
307 	int irq;
308 
309 	BUG_ON(qe_ic == NULL);
310 
311 	/* get the interrupt source vector. */
312 	irq = qe_ic_read(qe_ic->regs, QEIC_CHIVEC) >> 26;
313 
314 	if (irq == 0)
315 		return NO_IRQ;
316 
317 	return irq_linear_revmap(qe_ic->irqhost, irq);
318 }
319 
320 void __init qe_ic_init(struct device_node *node, unsigned int flags,
321 		       void (*low_handler)(struct irq_desc *desc),
322 		       void (*high_handler)(struct irq_desc *desc))
323 {
324 	struct qe_ic *qe_ic;
325 	struct resource res;
326 	u32 temp = 0, ret, high_active = 0;
327 
328 	ret = of_address_to_resource(node, 0, &res);
329 	if (ret)
330 		return;
331 
332 	qe_ic = kzalloc(sizeof(*qe_ic), GFP_KERNEL);
333 	if (qe_ic == NULL)
334 		return;
335 
336 	qe_ic->irqhost = irq_domain_add_linear(node, NR_QE_IC_INTS,
337 					       &qe_ic_host_ops, qe_ic);
338 	if (qe_ic->irqhost == NULL) {
339 		kfree(qe_ic);
340 		return;
341 	}
342 
343 	qe_ic->regs = ioremap(res.start, resource_size(&res));
344 
345 	qe_ic->hc_irq = qe_ic_irq_chip;
346 
347 	qe_ic->virq_high = irq_of_parse_and_map(node, 0);
348 	qe_ic->virq_low = irq_of_parse_and_map(node, 1);
349 
350 	if (qe_ic->virq_low == NO_IRQ) {
351 		printk(KERN_ERR "Failed to map QE_IC low IRQ\n");
352 		kfree(qe_ic);
353 		return;
354 	}
355 
356 	/* default priority scheme is grouped. If spread mode is    */
357 	/* required, configure cicr accordingly.                    */
358 	if (flags & QE_IC_SPREADMODE_GRP_W)
359 		temp |= CICR_GWCC;
360 	if (flags & QE_IC_SPREADMODE_GRP_X)
361 		temp |= CICR_GXCC;
362 	if (flags & QE_IC_SPREADMODE_GRP_Y)
363 		temp |= CICR_GYCC;
364 	if (flags & QE_IC_SPREADMODE_GRP_Z)
365 		temp |= CICR_GZCC;
366 	if (flags & QE_IC_SPREADMODE_GRP_RISCA)
367 		temp |= CICR_GRTA;
368 	if (flags & QE_IC_SPREADMODE_GRP_RISCB)
369 		temp |= CICR_GRTB;
370 
371 	/* choose destination signal for highest priority interrupt */
372 	if (flags & QE_IC_HIGH_SIGNAL) {
373 		temp |= (SIGNAL_HIGH << CICR_HPIT_SHIFT);
374 		high_active = 1;
375 	}
376 
377 	qe_ic_write(qe_ic->regs, QEIC_CICR, temp);
378 
379 	irq_set_handler_data(qe_ic->virq_low, qe_ic);
380 	irq_set_chained_handler(qe_ic->virq_low, low_handler);
381 
382 	if (qe_ic->virq_high != NO_IRQ &&
383 			qe_ic->virq_high != qe_ic->virq_low) {
384 		irq_set_handler_data(qe_ic->virq_high, qe_ic);
385 		irq_set_chained_handler(qe_ic->virq_high, high_handler);
386 	}
387 }
388 
389 void qe_ic_set_highest_priority(unsigned int virq, int high)
390 {
391 	struct qe_ic *qe_ic = qe_ic_from_irq(virq);
392 	unsigned int src = virq_to_hw(virq);
393 	u32 temp = 0;
394 
395 	temp = qe_ic_read(qe_ic->regs, QEIC_CICR);
396 
397 	temp &= ~CICR_HP_MASK;
398 	temp |= src << CICR_HP_SHIFT;
399 
400 	temp &= ~CICR_HPIT_MASK;
401 	temp |= (high ? SIGNAL_HIGH : SIGNAL_LOW) << CICR_HPIT_SHIFT;
402 
403 	qe_ic_write(qe_ic->regs, QEIC_CICR, temp);
404 }
405 
406 /* Set Priority level within its group, from 1 to 8 */
407 int qe_ic_set_priority(unsigned int virq, unsigned int priority)
408 {
409 	struct qe_ic *qe_ic = qe_ic_from_irq(virq);
410 	unsigned int src = virq_to_hw(virq);
411 	u32 temp;
412 
413 	if (priority > 8 || priority == 0)
414 		return -EINVAL;
415 	if (WARN_ONCE(src >= ARRAY_SIZE(qe_ic_info),
416 		      "%s: Invalid hw irq number for QEIC\n", __func__))
417 		return -EINVAL;
418 	if (qe_ic_info[src].pri_reg == 0)
419 		return -EINVAL;
420 
421 	temp = qe_ic_read(qe_ic->regs, qe_ic_info[src].pri_reg);
422 
423 	if (priority < 4) {
424 		temp &= ~(0x7 << (32 - priority * 3));
425 		temp |= qe_ic_info[src].pri_code << (32 - priority * 3);
426 	} else {
427 		temp &= ~(0x7 << (24 - priority * 3));
428 		temp |= qe_ic_info[src].pri_code << (24 - priority * 3);
429 	}
430 
431 	qe_ic_write(qe_ic->regs, qe_ic_info[src].pri_reg, temp);
432 
433 	return 0;
434 }
435 
436 /* Set a QE priority to use high irq, only priority 1~2 can use high irq */
437 int qe_ic_set_high_priority(unsigned int virq, unsigned int priority, int high)
438 {
439 	struct qe_ic *qe_ic = qe_ic_from_irq(virq);
440 	unsigned int src = virq_to_hw(virq);
441 	u32 temp, control_reg = QEIC_CICNR, shift = 0;
442 
443 	if (priority > 2 || priority == 0)
444 		return -EINVAL;
445 	if (WARN_ONCE(src >= ARRAY_SIZE(qe_ic_info),
446 		      "%s: Invalid hw irq number for QEIC\n", __func__))
447 		return -EINVAL;
448 
449 	switch (qe_ic_info[src].pri_reg) {
450 	case QEIC_CIPZCC:
451 		shift = CICNR_ZCC1T_SHIFT;
452 		break;
453 	case QEIC_CIPWCC:
454 		shift = CICNR_WCC1T_SHIFT;
455 		break;
456 	case QEIC_CIPYCC:
457 		shift = CICNR_YCC1T_SHIFT;
458 		break;
459 	case QEIC_CIPXCC:
460 		shift = CICNR_XCC1T_SHIFT;
461 		break;
462 	case QEIC_CIPRTA:
463 		shift = CRICR_RTA1T_SHIFT;
464 		control_reg = QEIC_CRICR;
465 		break;
466 	case QEIC_CIPRTB:
467 		shift = CRICR_RTB1T_SHIFT;
468 		control_reg = QEIC_CRICR;
469 		break;
470 	default:
471 		return -EINVAL;
472 	}
473 
474 	shift += (2 - priority) * 2;
475 	temp = qe_ic_read(qe_ic->regs, control_reg);
476 	temp &= ~(SIGNAL_MASK << shift);
477 	temp |= (high ? SIGNAL_HIGH : SIGNAL_LOW) << shift;
478 	qe_ic_write(qe_ic->regs, control_reg, temp);
479 
480 	return 0;
481 }
482 
483 static struct bus_type qe_ic_subsys = {
484 	.name = "qe_ic",
485 	.dev_name = "qe_ic",
486 };
487 
488 static struct device device_qe_ic = {
489 	.id = 0,
490 	.bus = &qe_ic_subsys,
491 };
492 
493 static int __init init_qe_ic_sysfs(void)
494 {
495 	int rc;
496 
497 	printk(KERN_DEBUG "Registering qe_ic with sysfs...\n");
498 
499 	rc = subsys_system_register(&qe_ic_subsys, NULL);
500 	if (rc) {
501 		printk(KERN_ERR "Failed registering qe_ic sys class\n");
502 		return -ENODEV;
503 	}
504 	rc = device_register(&device_qe_ic);
505 	if (rc) {
506 		printk(KERN_ERR "Failed registering qe_ic sys device\n");
507 		return -ENODEV;
508 	}
509 	return 0;
510 }
511 
512 subsys_initcall(init_qe_ic_sysfs);
513