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/bootmem.h>
27#include <linux/spinlock.h>
28#include <asm/irq.h>
29#include <asm/io.h>
30#include <asm/prom.h>
31#include <asm/qe_ic.h>
32
33#include "qe_ic.h"
34
35static DEFINE_RAW_SPINLOCK(qe_ic_lock);
36
37static 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
178static inline u32 qe_ic_read(volatile __be32  __iomem * base, unsigned int reg)
179{
180	return in_be32(base + (reg >> 2));
181}
182
183static 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
189static inline struct qe_ic *qe_ic_from_irq(unsigned int virq)
190{
191	return irq_get_chip_data(virq);
192}
193
194static 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
199static 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
215static 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
241static 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
248static int qe_ic_host_match(struct irq_domain *h, struct device_node *node)
249{
250	/* Exact match, unless qe_ic node is NULL */
251	return h->of_node == NULL || h->of_node == node;
252}
253
254static int qe_ic_host_map(struct irq_domain *h, unsigned int virq,
255			  irq_hw_number_t hw)
256{
257	struct qe_ic *qe_ic = h->host_data;
258	struct irq_chip *chip;
259
260	if (qe_ic_info[hw].mask == 0) {
261		printk(KERN_ERR "Can't map reserved IRQ\n");
262		return -EINVAL;
263	}
264	/* Default chip */
265	chip = &qe_ic->hc_irq;
266
267	irq_set_chip_data(virq, qe_ic);
268	irq_set_status_flags(virq, IRQ_LEVEL);
269
270	irq_set_chip_and_handler(virq, chip, handle_level_irq);
271
272	return 0;
273}
274
275static struct irq_domain_ops qe_ic_host_ops = {
276	.match = qe_ic_host_match,
277	.map = qe_ic_host_map,
278	.xlate = irq_domain_xlate_onetwocell,
279};
280
281/* Return an interrupt vector or NO_IRQ if no interrupt is pending. */
282unsigned int qe_ic_get_low_irq(struct qe_ic *qe_ic)
283{
284	int irq;
285
286	BUG_ON(qe_ic == NULL);
287
288	/* get the interrupt source vector. */
289	irq = qe_ic_read(qe_ic->regs, QEIC_CIVEC) >> 26;
290
291	if (irq == 0)
292		return NO_IRQ;
293
294	return irq_linear_revmap(qe_ic->irqhost, irq);
295}
296
297/* Return an interrupt vector or NO_IRQ if no interrupt is pending. */
298unsigned int qe_ic_get_high_irq(struct qe_ic *qe_ic)
299{
300	int irq;
301
302	BUG_ON(qe_ic == NULL);
303
304	/* get the interrupt source vector. */
305	irq = qe_ic_read(qe_ic->regs, QEIC_CHIVEC) >> 26;
306
307	if (irq == 0)
308		return NO_IRQ;
309
310	return irq_linear_revmap(qe_ic->irqhost, irq);
311}
312
313void __init qe_ic_init(struct device_node *node, unsigned int flags,
314		void (*low_handler)(unsigned int irq, struct irq_desc *desc),
315		void (*high_handler)(unsigned int irq, struct irq_desc *desc))
316{
317	struct qe_ic *qe_ic;
318	struct resource res;
319	u32 temp = 0, ret, high_active = 0;
320
321	ret = of_address_to_resource(node, 0, &res);
322	if (ret)
323		return;
324
325	qe_ic = kzalloc(sizeof(*qe_ic), GFP_KERNEL);
326	if (qe_ic == NULL)
327		return;
328
329	qe_ic->irqhost = irq_domain_add_linear(node, NR_QE_IC_INTS,
330					       &qe_ic_host_ops, qe_ic);
331	if (qe_ic->irqhost == NULL) {
332		kfree(qe_ic);
333		return;
334	}
335
336	qe_ic->regs = ioremap(res.start, resource_size(&res));
337
338	qe_ic->hc_irq = qe_ic_irq_chip;
339
340	qe_ic->virq_high = irq_of_parse_and_map(node, 0);
341	qe_ic->virq_low = irq_of_parse_and_map(node, 1);
342
343	if (qe_ic->virq_low == NO_IRQ) {
344		printk(KERN_ERR "Failed to map QE_IC low IRQ\n");
345		kfree(qe_ic);
346		return;
347	}
348
349	/* default priority scheme is grouped. If spread mode is    */
350	/* required, configure cicr accordingly.                    */
351	if (flags & QE_IC_SPREADMODE_GRP_W)
352		temp |= CICR_GWCC;
353	if (flags & QE_IC_SPREADMODE_GRP_X)
354		temp |= CICR_GXCC;
355	if (flags & QE_IC_SPREADMODE_GRP_Y)
356		temp |= CICR_GYCC;
357	if (flags & QE_IC_SPREADMODE_GRP_Z)
358		temp |= CICR_GZCC;
359	if (flags & QE_IC_SPREADMODE_GRP_RISCA)
360		temp |= CICR_GRTA;
361	if (flags & QE_IC_SPREADMODE_GRP_RISCB)
362		temp |= CICR_GRTB;
363
364	/* choose destination signal for highest priority interrupt */
365	if (flags & QE_IC_HIGH_SIGNAL) {
366		temp |= (SIGNAL_HIGH << CICR_HPIT_SHIFT);
367		high_active = 1;
368	}
369
370	qe_ic_write(qe_ic->regs, QEIC_CICR, temp);
371
372	irq_set_handler_data(qe_ic->virq_low, qe_ic);
373	irq_set_chained_handler(qe_ic->virq_low, low_handler);
374
375	if (qe_ic->virq_high != NO_IRQ &&
376			qe_ic->virq_high != qe_ic->virq_low) {
377		irq_set_handler_data(qe_ic->virq_high, qe_ic);
378		irq_set_chained_handler(qe_ic->virq_high, high_handler);
379	}
380}
381
382void qe_ic_set_highest_priority(unsigned int virq, int high)
383{
384	struct qe_ic *qe_ic = qe_ic_from_irq(virq);
385	unsigned int src = virq_to_hw(virq);
386	u32 temp = 0;
387
388	temp = qe_ic_read(qe_ic->regs, QEIC_CICR);
389
390	temp &= ~CICR_HP_MASK;
391	temp |= src << CICR_HP_SHIFT;
392
393	temp &= ~CICR_HPIT_MASK;
394	temp |= (high ? SIGNAL_HIGH : SIGNAL_LOW) << CICR_HPIT_SHIFT;
395
396	qe_ic_write(qe_ic->regs, QEIC_CICR, temp);
397}
398
399/* Set Priority level within its group, from 1 to 8 */
400int qe_ic_set_priority(unsigned int virq, unsigned int priority)
401{
402	struct qe_ic *qe_ic = qe_ic_from_irq(virq);
403	unsigned int src = virq_to_hw(virq);
404	u32 temp;
405
406	if (priority > 8 || priority == 0)
407		return -EINVAL;
408	if (src > 127)
409		return -EINVAL;
410	if (qe_ic_info[src].pri_reg == 0)
411		return -EINVAL;
412
413	temp = qe_ic_read(qe_ic->regs, qe_ic_info[src].pri_reg);
414
415	if (priority < 4) {
416		temp &= ~(0x7 << (32 - priority * 3));
417		temp |= qe_ic_info[src].pri_code << (32 - priority * 3);
418	} else {
419		temp &= ~(0x7 << (24 - priority * 3));
420		temp |= qe_ic_info[src].pri_code << (24 - priority * 3);
421	}
422
423	qe_ic_write(qe_ic->regs, qe_ic_info[src].pri_reg, temp);
424
425	return 0;
426}
427
428/* Set a QE priority to use high irq, only priority 1~2 can use high irq */
429int qe_ic_set_high_priority(unsigned int virq, unsigned int priority, int high)
430{
431	struct qe_ic *qe_ic = qe_ic_from_irq(virq);
432	unsigned int src = virq_to_hw(virq);
433	u32 temp, control_reg = QEIC_CICNR, shift = 0;
434
435	if (priority > 2 || priority == 0)
436		return -EINVAL;
437
438	switch (qe_ic_info[src].pri_reg) {
439	case QEIC_CIPZCC:
440		shift = CICNR_ZCC1T_SHIFT;
441		break;
442	case QEIC_CIPWCC:
443		shift = CICNR_WCC1T_SHIFT;
444		break;
445	case QEIC_CIPYCC:
446		shift = CICNR_YCC1T_SHIFT;
447		break;
448	case QEIC_CIPXCC:
449		shift = CICNR_XCC1T_SHIFT;
450		break;
451	case QEIC_CIPRTA:
452		shift = CRICR_RTA1T_SHIFT;
453		control_reg = QEIC_CRICR;
454		break;
455	case QEIC_CIPRTB:
456		shift = CRICR_RTB1T_SHIFT;
457		control_reg = QEIC_CRICR;
458		break;
459	default:
460		return -EINVAL;
461	}
462
463	shift += (2 - priority) * 2;
464	temp = qe_ic_read(qe_ic->regs, control_reg);
465	temp &= ~(SIGNAL_MASK << shift);
466	temp |= (high ? SIGNAL_HIGH : SIGNAL_LOW) << shift;
467	qe_ic_write(qe_ic->regs, control_reg, temp);
468
469	return 0;
470}
471
472static struct bus_type qe_ic_subsys = {
473	.name = "qe_ic",
474	.dev_name = "qe_ic",
475};
476
477static struct device device_qe_ic = {
478	.id = 0,
479	.bus = &qe_ic_subsys,
480};
481
482static int __init init_qe_ic_sysfs(void)
483{
484	int rc;
485
486	printk(KERN_DEBUG "Registering qe_ic with sysfs...\n");
487
488	rc = subsys_system_register(&qe_ic_subsys, NULL);
489	if (rc) {
490		printk(KERN_ERR "Failed registering qe_ic sys class\n");
491		return -ENODEV;
492	}
493	rc = device_register(&device_qe_ic);
494	if (rc) {
495		printk(KERN_ERR "Failed registering qe_ic sys device\n");
496		return -ENODEV;
497	}
498	return 0;
499}
500
501subsys_initcall(init_qe_ic_sysfs);
502