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