xref: /openbmc/linux/drivers/soc/fsl/qe/qe_ic.c (revision 8dde5715)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * arch/powerpc/sysdev/qe_lib/qe_ic.c
4  *
5  * Copyright (C) 2006 Freescale Semiconductor, Inc.  All rights reserved.
6  *
7  * Author: Li Yang <leoli@freescale.com>
8  * Based on code from Shlomi Gridish <gridish@freescale.com>
9  *
10  * QUICC ENGINE Interrupt Controller
11  */
12 
13 #include <linux/of_irq.h>
14 #include <linux/of_address.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/errno.h>
18 #include <linux/reboot.h>
19 #include <linux/slab.h>
20 #include <linux/stddef.h>
21 #include <linux/sched.h>
22 #include <linux/signal.h>
23 #include <linux/device.h>
24 #include <linux/spinlock.h>
25 #include <asm/irq.h>
26 #include <asm/io.h>
27 #include <soc/fsl/qe/qe_ic.h>
28 
29 #include "qe_ic.h"
30 
31 static DEFINE_RAW_SPINLOCK(qe_ic_lock);
32 
33 static struct qe_ic_info qe_ic_info[] = {
34 	[1] = {
35 	       .mask = 0x00008000,
36 	       .mask_reg = QEIC_CIMR,
37 	       .pri_code = 0,
38 	       .pri_reg = QEIC_CIPWCC,
39 	       },
40 	[2] = {
41 	       .mask = 0x00004000,
42 	       .mask_reg = QEIC_CIMR,
43 	       .pri_code = 1,
44 	       .pri_reg = QEIC_CIPWCC,
45 	       },
46 	[3] = {
47 	       .mask = 0x00002000,
48 	       .mask_reg = QEIC_CIMR,
49 	       .pri_code = 2,
50 	       .pri_reg = QEIC_CIPWCC,
51 	       },
52 	[10] = {
53 		.mask = 0x00000040,
54 		.mask_reg = QEIC_CIMR,
55 		.pri_code = 1,
56 		.pri_reg = QEIC_CIPZCC,
57 		},
58 	[11] = {
59 		.mask = 0x00000020,
60 		.mask_reg = QEIC_CIMR,
61 		.pri_code = 2,
62 		.pri_reg = QEIC_CIPZCC,
63 		},
64 	[12] = {
65 		.mask = 0x00000010,
66 		.mask_reg = QEIC_CIMR,
67 		.pri_code = 3,
68 		.pri_reg = QEIC_CIPZCC,
69 		},
70 	[13] = {
71 		.mask = 0x00000008,
72 		.mask_reg = QEIC_CIMR,
73 		.pri_code = 4,
74 		.pri_reg = QEIC_CIPZCC,
75 		},
76 	[14] = {
77 		.mask = 0x00000004,
78 		.mask_reg = QEIC_CIMR,
79 		.pri_code = 5,
80 		.pri_reg = QEIC_CIPZCC,
81 		},
82 	[15] = {
83 		.mask = 0x00000002,
84 		.mask_reg = QEIC_CIMR,
85 		.pri_code = 6,
86 		.pri_reg = QEIC_CIPZCC,
87 		},
88 	[20] = {
89 		.mask = 0x10000000,
90 		.mask_reg = QEIC_CRIMR,
91 		.pri_code = 3,
92 		.pri_reg = QEIC_CIPRTA,
93 		},
94 	[25] = {
95 		.mask = 0x00800000,
96 		.mask_reg = QEIC_CRIMR,
97 		.pri_code = 0,
98 		.pri_reg = QEIC_CIPRTB,
99 		},
100 	[26] = {
101 		.mask = 0x00400000,
102 		.mask_reg = QEIC_CRIMR,
103 		.pri_code = 1,
104 		.pri_reg = QEIC_CIPRTB,
105 		},
106 	[27] = {
107 		.mask = 0x00200000,
108 		.mask_reg = QEIC_CRIMR,
109 		.pri_code = 2,
110 		.pri_reg = QEIC_CIPRTB,
111 		},
112 	[28] = {
113 		.mask = 0x00100000,
114 		.mask_reg = QEIC_CRIMR,
115 		.pri_code = 3,
116 		.pri_reg = QEIC_CIPRTB,
117 		},
118 	[32] = {
119 		.mask = 0x80000000,
120 		.mask_reg = QEIC_CIMR,
121 		.pri_code = 0,
122 		.pri_reg = QEIC_CIPXCC,
123 		},
124 	[33] = {
125 		.mask = 0x40000000,
126 		.mask_reg = QEIC_CIMR,
127 		.pri_code = 1,
128 		.pri_reg = QEIC_CIPXCC,
129 		},
130 	[34] = {
131 		.mask = 0x20000000,
132 		.mask_reg = QEIC_CIMR,
133 		.pri_code = 2,
134 		.pri_reg = QEIC_CIPXCC,
135 		},
136 	[35] = {
137 		.mask = 0x10000000,
138 		.mask_reg = QEIC_CIMR,
139 		.pri_code = 3,
140 		.pri_reg = QEIC_CIPXCC,
141 		},
142 	[36] = {
143 		.mask = 0x08000000,
144 		.mask_reg = QEIC_CIMR,
145 		.pri_code = 4,
146 		.pri_reg = QEIC_CIPXCC,
147 		},
148 	[40] = {
149 		.mask = 0x00800000,
150 		.mask_reg = QEIC_CIMR,
151 		.pri_code = 0,
152 		.pri_reg = QEIC_CIPYCC,
153 		},
154 	[41] = {
155 		.mask = 0x00400000,
156 		.mask_reg = QEIC_CIMR,
157 		.pri_code = 1,
158 		.pri_reg = QEIC_CIPYCC,
159 		},
160 	[42] = {
161 		.mask = 0x00200000,
162 		.mask_reg = QEIC_CIMR,
163 		.pri_code = 2,
164 		.pri_reg = QEIC_CIPYCC,
165 		},
166 	[43] = {
167 		.mask = 0x00100000,
168 		.mask_reg = QEIC_CIMR,
169 		.pri_code = 3,
170 		.pri_reg = QEIC_CIPYCC,
171 		},
172 };
173 
174 static inline u32 qe_ic_read(volatile __be32  __iomem * base, unsigned int reg)
175 {
176 	return in_be32(base + (reg >> 2));
177 }
178 
179 static inline void qe_ic_write(volatile __be32  __iomem * base, unsigned int reg,
180 			       u32 value)
181 {
182 	out_be32(base + (reg >> 2), value);
183 }
184 
185 static inline struct qe_ic *qe_ic_from_irq(unsigned int virq)
186 {
187 	return irq_get_chip_data(virq);
188 }
189 
190 static inline struct qe_ic *qe_ic_from_irq_data(struct irq_data *d)
191 {
192 	return irq_data_get_irq_chip_data(d);
193 }
194 
195 static void qe_ic_unmask_irq(struct irq_data *d)
196 {
197 	struct qe_ic *qe_ic = qe_ic_from_irq_data(d);
198 	unsigned int src = irqd_to_hwirq(d);
199 	unsigned long flags;
200 	u32 temp;
201 
202 	raw_spin_lock_irqsave(&qe_ic_lock, flags);
203 
204 	temp = qe_ic_read(qe_ic->regs, qe_ic_info[src].mask_reg);
205 	qe_ic_write(qe_ic->regs, qe_ic_info[src].mask_reg,
206 		    temp | qe_ic_info[src].mask);
207 
208 	raw_spin_unlock_irqrestore(&qe_ic_lock, flags);
209 }
210 
211 static void qe_ic_mask_irq(struct irq_data *d)
212 {
213 	struct qe_ic *qe_ic = qe_ic_from_irq_data(d);
214 	unsigned int src = irqd_to_hwirq(d);
215 	unsigned long flags;
216 	u32 temp;
217 
218 	raw_spin_lock_irqsave(&qe_ic_lock, flags);
219 
220 	temp = qe_ic_read(qe_ic->regs, qe_ic_info[src].mask_reg);
221 	qe_ic_write(qe_ic->regs, qe_ic_info[src].mask_reg,
222 		    temp & ~qe_ic_info[src].mask);
223 
224 	/* Flush the above write before enabling interrupts; otherwise,
225 	 * spurious interrupts will sometimes happen.  To be 100% sure
226 	 * that the write has reached the device before interrupts are
227 	 * enabled, the mask register would have to be read back; however,
228 	 * this is not required for correctness, only to avoid wasting
229 	 * time on a large number of spurious interrupts.  In testing,
230 	 * a sync reduced the observed spurious interrupts to zero.
231 	 */
232 	mb();
233 
234 	raw_spin_unlock_irqrestore(&qe_ic_lock, flags);
235 }
236 
237 static struct irq_chip qe_ic_irq_chip = {
238 	.name = "QEIC",
239 	.irq_unmask = qe_ic_unmask_irq,
240 	.irq_mask = qe_ic_mask_irq,
241 	.irq_mask_ack = qe_ic_mask_irq,
242 };
243 
244 static int qe_ic_host_match(struct irq_domain *h, struct device_node *node,
245 			    enum irq_domain_bus_token bus_token)
246 {
247 	/* Exact match, unless qe_ic node is NULL */
248 	struct device_node *of_node = irq_domain_get_of_node(h);
249 	return of_node == NULL || of_node == node;
250 }
251 
252 static int qe_ic_host_map(struct irq_domain *h, unsigned int virq,
253 			  irq_hw_number_t hw)
254 {
255 	struct qe_ic *qe_ic = h->host_data;
256 	struct irq_chip *chip;
257 
258 	if (hw >= ARRAY_SIZE(qe_ic_info)) {
259 		pr_err("%s: Invalid hw irq number for QEIC\n", __func__);
260 		return -EINVAL;
261 	}
262 
263 	if (qe_ic_info[hw].mask == 0) {
264 		printk(KERN_ERR "Can't map reserved IRQ\n");
265 		return -EINVAL;
266 	}
267 	/* Default chip */
268 	chip = &qe_ic->hc_irq;
269 
270 	irq_set_chip_data(virq, qe_ic);
271 	irq_set_status_flags(virq, IRQ_LEVEL);
272 
273 	irq_set_chip_and_handler(virq, chip, handle_level_irq);
274 
275 	return 0;
276 }
277 
278 static const struct irq_domain_ops qe_ic_host_ops = {
279 	.match = qe_ic_host_match,
280 	.map = qe_ic_host_map,
281 	.xlate = irq_domain_xlate_onetwocell,
282 };
283 
284 /* Return an interrupt vector or NO_IRQ if no interrupt is pending. */
285 unsigned int qe_ic_get_low_irq(struct qe_ic *qe_ic)
286 {
287 	int irq;
288 
289 	BUG_ON(qe_ic == NULL);
290 
291 	/* get the interrupt source vector. */
292 	irq = qe_ic_read(qe_ic->regs, QEIC_CIVEC) >> 26;
293 
294 	if (irq == 0)
295 		return NO_IRQ;
296 
297 	return irq_linear_revmap(qe_ic->irqhost, irq);
298 }
299 
300 /* Return an interrupt vector or NO_IRQ if no interrupt is pending. */
301 unsigned int qe_ic_get_high_irq(struct qe_ic *qe_ic)
302 {
303 	int irq;
304 
305 	BUG_ON(qe_ic == NULL);
306 
307 	/* get the interrupt source vector. */
308 	irq = qe_ic_read(qe_ic->regs, QEIC_CHIVEC) >> 26;
309 
310 	if (irq == 0)
311 		return NO_IRQ;
312 
313 	return irq_linear_revmap(qe_ic->irqhost, irq);
314 }
315 
316 void __init qe_ic_init(struct device_node *node, unsigned int flags,
317 		       void (*low_handler)(struct irq_desc *desc),
318 		       void (*high_handler)(struct irq_desc *desc))
319 {
320 	struct qe_ic *qe_ic;
321 	struct resource res;
322 	u32 temp = 0, ret, high_active = 0;
323 
324 	ret = of_address_to_resource(node, 0, &res);
325 	if (ret)
326 		return;
327 
328 	qe_ic = kzalloc(sizeof(*qe_ic), GFP_KERNEL);
329 	if (qe_ic == NULL)
330 		return;
331 
332 	qe_ic->irqhost = irq_domain_add_linear(node, NR_QE_IC_INTS,
333 					       &qe_ic_host_ops, qe_ic);
334 	if (qe_ic->irqhost == NULL) {
335 		kfree(qe_ic);
336 		return;
337 	}
338 
339 	qe_ic->regs = ioremap(res.start, resource_size(&res));
340 
341 	qe_ic->hc_irq = qe_ic_irq_chip;
342 
343 	qe_ic->virq_high = irq_of_parse_and_map(node, 0);
344 	qe_ic->virq_low = irq_of_parse_and_map(node, 1);
345 
346 	if (qe_ic->virq_low == NO_IRQ) {
347 		printk(KERN_ERR "Failed to map QE_IC low IRQ\n");
348 		kfree(qe_ic);
349 		return;
350 	}
351 
352 	/* default priority scheme is grouped. If spread mode is    */
353 	/* required, configure cicr accordingly.                    */
354 	if (flags & QE_IC_SPREADMODE_GRP_W)
355 		temp |= CICR_GWCC;
356 	if (flags & QE_IC_SPREADMODE_GRP_X)
357 		temp |= CICR_GXCC;
358 	if (flags & QE_IC_SPREADMODE_GRP_Y)
359 		temp |= CICR_GYCC;
360 	if (flags & QE_IC_SPREADMODE_GRP_Z)
361 		temp |= CICR_GZCC;
362 	if (flags & QE_IC_SPREADMODE_GRP_RISCA)
363 		temp |= CICR_GRTA;
364 	if (flags & QE_IC_SPREADMODE_GRP_RISCB)
365 		temp |= CICR_GRTB;
366 
367 	/* choose destination signal for highest priority interrupt */
368 	if (flags & QE_IC_HIGH_SIGNAL) {
369 		temp |= (SIGNAL_HIGH << CICR_HPIT_SHIFT);
370 		high_active = 1;
371 	}
372 
373 	qe_ic_write(qe_ic->regs, QEIC_CICR, temp);
374 
375 	irq_set_handler_data(qe_ic->virq_low, qe_ic);
376 	irq_set_chained_handler(qe_ic->virq_low, low_handler);
377 
378 	if (qe_ic->virq_high != NO_IRQ &&
379 			qe_ic->virq_high != qe_ic->virq_low) {
380 		irq_set_handler_data(qe_ic->virq_high, qe_ic);
381 		irq_set_chained_handler(qe_ic->virq_high, high_handler);
382 	}
383 }
384 
385 void qe_ic_set_highest_priority(unsigned int virq, int high)
386 {
387 	struct qe_ic *qe_ic = qe_ic_from_irq(virq);
388 	unsigned int src = virq_to_hw(virq);
389 	u32 temp = 0;
390 
391 	temp = qe_ic_read(qe_ic->regs, QEIC_CICR);
392 
393 	temp &= ~CICR_HP_MASK;
394 	temp |= src << CICR_HP_SHIFT;
395 
396 	temp &= ~CICR_HPIT_MASK;
397 	temp |= (high ? SIGNAL_HIGH : SIGNAL_LOW) << CICR_HPIT_SHIFT;
398 
399 	qe_ic_write(qe_ic->regs, QEIC_CICR, temp);
400 }
401 
402 /* Set Priority level within its group, from 1 to 8 */
403 int qe_ic_set_priority(unsigned int virq, unsigned int priority)
404 {
405 	struct qe_ic *qe_ic = qe_ic_from_irq(virq);
406 	unsigned int src = virq_to_hw(virq);
407 	u32 temp;
408 
409 	if (priority > 8 || priority == 0)
410 		return -EINVAL;
411 	if (WARN_ONCE(src >= ARRAY_SIZE(qe_ic_info),
412 		      "%s: Invalid hw irq number for QEIC\n", __func__))
413 		return -EINVAL;
414 	if (qe_ic_info[src].pri_reg == 0)
415 		return -EINVAL;
416 
417 	temp = qe_ic_read(qe_ic->regs, qe_ic_info[src].pri_reg);
418 
419 	if (priority < 4) {
420 		temp &= ~(0x7 << (32 - priority * 3));
421 		temp |= qe_ic_info[src].pri_code << (32 - priority * 3);
422 	} else {
423 		temp &= ~(0x7 << (24 - priority * 3));
424 		temp |= qe_ic_info[src].pri_code << (24 - priority * 3);
425 	}
426 
427 	qe_ic_write(qe_ic->regs, qe_ic_info[src].pri_reg, temp);
428 
429 	return 0;
430 }
431 
432 /* Set a QE priority to use high irq, only priority 1~2 can use high irq */
433 int qe_ic_set_high_priority(unsigned int virq, unsigned int priority, int high)
434 {
435 	struct qe_ic *qe_ic = qe_ic_from_irq(virq);
436 	unsigned int src = virq_to_hw(virq);
437 	u32 temp, control_reg = QEIC_CICNR, shift = 0;
438 
439 	if (priority > 2 || priority == 0)
440 		return -EINVAL;
441 	if (WARN_ONCE(src >= ARRAY_SIZE(qe_ic_info),
442 		      "%s: Invalid hw irq number for QEIC\n", __func__))
443 		return -EINVAL;
444 
445 	switch (qe_ic_info[src].pri_reg) {
446 	case QEIC_CIPZCC:
447 		shift = CICNR_ZCC1T_SHIFT;
448 		break;
449 	case QEIC_CIPWCC:
450 		shift = CICNR_WCC1T_SHIFT;
451 		break;
452 	case QEIC_CIPYCC:
453 		shift = CICNR_YCC1T_SHIFT;
454 		break;
455 	case QEIC_CIPXCC:
456 		shift = CICNR_XCC1T_SHIFT;
457 		break;
458 	case QEIC_CIPRTA:
459 		shift = CRICR_RTA1T_SHIFT;
460 		control_reg = QEIC_CRICR;
461 		break;
462 	case QEIC_CIPRTB:
463 		shift = CRICR_RTB1T_SHIFT;
464 		control_reg = QEIC_CRICR;
465 		break;
466 	default:
467 		return -EINVAL;
468 	}
469 
470 	shift += (2 - priority) * 2;
471 	temp = qe_ic_read(qe_ic->regs, control_reg);
472 	temp &= ~(SIGNAL_MASK << shift);
473 	temp |= (high ? SIGNAL_HIGH : SIGNAL_LOW) << shift;
474 	qe_ic_write(qe_ic->regs, control_reg, temp);
475 
476 	return 0;
477 }
478 
479 static struct bus_type qe_ic_subsys = {
480 	.name = "qe_ic",
481 	.dev_name = "qe_ic",
482 };
483 
484 static struct device device_qe_ic = {
485 	.id = 0,
486 	.bus = &qe_ic_subsys,
487 };
488 
489 static int __init init_qe_ic_sysfs(void)
490 {
491 	int rc;
492 
493 	printk(KERN_DEBUG "Registering qe_ic with sysfs...\n");
494 
495 	rc = subsys_system_register(&qe_ic_subsys, NULL);
496 	if (rc) {
497 		printk(KERN_ERR "Failed registering qe_ic sys class\n");
498 		return -ENODEV;
499 	}
500 	rc = device_register(&device_qe_ic);
501 	if (rc) {
502 		printk(KERN_ERR "Failed registering qe_ic sys device\n");
503 		return -ENODEV;
504 	}
505 	return 0;
506 }
507 
508 subsys_initcall(init_qe_ic_sysfs);
509