1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2015 Endless Mobile, Inc.
4 * Author: Carlo Caione <carlo@endlessm.com>
5 * Copyright (c) 2016 BayLibre, SAS.
6 * Author: Jerome Brunet <jbrunet@baylibre.com>
7 */
8
9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10
11#include <linux/io.h>
12#include <linux/module.h>
13#include <linux/irq.h>
14#include <linux/irqdomain.h>
15#include <linux/irqchip.h>
16#include <linux/of.h>
17#include <linux/of_address.h>
18
19#define MAX_NUM_CHANNEL 64
20#define MAX_INPUT_MUX 256
21
22#define REG_EDGE_POL	0x00
23#define REG_PIN_03_SEL	0x04
24#define REG_PIN_47_SEL	0x08
25#define REG_FILTER_SEL	0x0c
26
27/* use for A1 like chips */
28#define REG_PIN_A1_SEL	0x04
29/* Used for s4 chips */
30#define REG_EDGE_POL_S4	0x1c
31
32/*
33 * Note: The S905X3 datasheet reports that BOTH_EDGE is controlled by
34 * bits 24 to 31. Tests on the actual HW show that these bits are
35 * stuck at 0. Bits 8 to 15 are responsive and have the expected
36 * effect.
37 */
38#define REG_EDGE_POL_EDGE(params, x)	BIT((params)->edge_single_offset + (x))
39#define REG_EDGE_POL_LOW(params, x)	BIT((params)->pol_low_offset + (x))
40#define REG_BOTH_EDGE(params, x)	BIT((params)->edge_both_offset + (x))
41#define REG_EDGE_POL_MASK(params, x)    (	\
42		REG_EDGE_POL_EDGE(params, x) |	\
43		REG_EDGE_POL_LOW(params, x)  |	\
44		REG_BOTH_EDGE(params, x))
45#define REG_PIN_SEL_SHIFT(x)	(((x) % 4) * 8)
46#define REG_FILTER_SEL_SHIFT(x)	((x) * 4)
47
48struct meson_gpio_irq_controller;
49static void meson8_gpio_irq_sel_pin(struct meson_gpio_irq_controller *ctl,
50				    unsigned int channel, unsigned long hwirq);
51static void meson_gpio_irq_init_dummy(struct meson_gpio_irq_controller *ctl);
52static void meson_a1_gpio_irq_sel_pin(struct meson_gpio_irq_controller *ctl,
53				      unsigned int channel,
54				      unsigned long hwirq);
55static void meson_a1_gpio_irq_init(struct meson_gpio_irq_controller *ctl);
56static int meson8_gpio_irq_set_type(struct meson_gpio_irq_controller *ctl,
57				    unsigned int type, u32 *channel_hwirq);
58static int meson_s4_gpio_irq_set_type(struct meson_gpio_irq_controller *ctl,
59				      unsigned int type, u32 *channel_hwirq);
60
61struct irq_ctl_ops {
62	void (*gpio_irq_sel_pin)(struct meson_gpio_irq_controller *ctl,
63				 unsigned int channel, unsigned long hwirq);
64	void (*gpio_irq_init)(struct meson_gpio_irq_controller *ctl);
65	int (*gpio_irq_set_type)(struct meson_gpio_irq_controller *ctl,
66				 unsigned int type, u32 *channel_hwirq);
67};
68
69struct meson_gpio_irq_params {
70	unsigned int nr_hwirq;
71	unsigned int nr_channels;
72	bool support_edge_both;
73	unsigned int edge_both_offset;
74	unsigned int edge_single_offset;
75	unsigned int pol_low_offset;
76	unsigned int pin_sel_mask;
77	struct irq_ctl_ops ops;
78};
79
80#define INIT_MESON_COMMON(irqs, init, sel, type)		\
81	.nr_hwirq = irqs,					\
82	.ops = {						\
83		.gpio_irq_init = init,				\
84		.gpio_irq_sel_pin = sel,			\
85		.gpio_irq_set_type = type,			\
86	},
87
88#define INIT_MESON8_COMMON_DATA(irqs)				\
89	INIT_MESON_COMMON(irqs, meson_gpio_irq_init_dummy,	\
90			  meson8_gpio_irq_sel_pin,		\
91			  meson8_gpio_irq_set_type)		\
92	.edge_single_offset = 0,				\
93	.pol_low_offset = 16,					\
94	.pin_sel_mask = 0xff,					\
95	.nr_channels = 8,					\
96
97#define INIT_MESON_A1_COMMON_DATA(irqs)				\
98	INIT_MESON_COMMON(irqs, meson_a1_gpio_irq_init,		\
99			  meson_a1_gpio_irq_sel_pin,		\
100			  meson8_gpio_irq_set_type)		\
101	.support_edge_both = true,				\
102	.edge_both_offset = 16,					\
103	.edge_single_offset = 8,				\
104	.pol_low_offset = 0,					\
105	.pin_sel_mask = 0x7f,					\
106	.nr_channels = 8,					\
107
108#define INIT_MESON_S4_COMMON_DATA(irqs)				\
109	INIT_MESON_COMMON(irqs, meson_a1_gpio_irq_init,		\
110			  meson_a1_gpio_irq_sel_pin,		\
111			  meson_s4_gpio_irq_set_type)		\
112	.support_edge_both = true,				\
113	.edge_both_offset = 0,					\
114	.edge_single_offset = 12,				\
115	.pol_low_offset = 0,					\
116	.pin_sel_mask = 0xff,					\
117	.nr_channels = 12,					\
118
119static const struct meson_gpio_irq_params meson8_params = {
120	INIT_MESON8_COMMON_DATA(134)
121};
122
123static const struct meson_gpio_irq_params meson8b_params = {
124	INIT_MESON8_COMMON_DATA(119)
125};
126
127static const struct meson_gpio_irq_params gxbb_params = {
128	INIT_MESON8_COMMON_DATA(133)
129};
130
131static const struct meson_gpio_irq_params gxl_params = {
132	INIT_MESON8_COMMON_DATA(110)
133};
134
135static const struct meson_gpio_irq_params axg_params = {
136	INIT_MESON8_COMMON_DATA(100)
137};
138
139static const struct meson_gpio_irq_params sm1_params = {
140	INIT_MESON8_COMMON_DATA(100)
141	.support_edge_both = true,
142	.edge_both_offset = 8,
143};
144
145static const struct meson_gpio_irq_params a1_params = {
146	INIT_MESON_A1_COMMON_DATA(62)
147};
148
149static const struct meson_gpio_irq_params s4_params = {
150	INIT_MESON_S4_COMMON_DATA(82)
151};
152
153static const struct meson_gpio_irq_params c3_params = {
154	INIT_MESON_S4_COMMON_DATA(55)
155};
156
157static const struct meson_gpio_irq_params t7_params = {
158	INIT_MESON_S4_COMMON_DATA(157)
159};
160
161static const struct of_device_id meson_irq_gpio_matches[] __maybe_unused = {
162	{ .compatible = "amlogic,meson8-gpio-intc", .data = &meson8_params },
163	{ .compatible = "amlogic,meson8b-gpio-intc", .data = &meson8b_params },
164	{ .compatible = "amlogic,meson-gxbb-gpio-intc", .data = &gxbb_params },
165	{ .compatible = "amlogic,meson-gxl-gpio-intc", .data = &gxl_params },
166	{ .compatible = "amlogic,meson-axg-gpio-intc", .data = &axg_params },
167	{ .compatible = "amlogic,meson-g12a-gpio-intc", .data = &axg_params },
168	{ .compatible = "amlogic,meson-sm1-gpio-intc", .data = &sm1_params },
169	{ .compatible = "amlogic,meson-a1-gpio-intc", .data = &a1_params },
170	{ .compatible = "amlogic,meson-s4-gpio-intc", .data = &s4_params },
171	{ .compatible = "amlogic,c3-gpio-intc", .data = &c3_params },
172	{ .compatible = "amlogic,t7-gpio-intc", .data = &t7_params },
173	{ }
174};
175
176struct meson_gpio_irq_controller {
177	const struct meson_gpio_irq_params *params;
178	void __iomem *base;
179	u32 channel_irqs[MAX_NUM_CHANNEL];
180	DECLARE_BITMAP(channel_map, MAX_NUM_CHANNEL);
181	spinlock_t lock;
182};
183
184static void meson_gpio_irq_update_bits(struct meson_gpio_irq_controller *ctl,
185				       unsigned int reg, u32 mask, u32 val)
186{
187	unsigned long flags;
188	u32 tmp;
189
190	spin_lock_irqsave(&ctl->lock, flags);
191
192	tmp = readl_relaxed(ctl->base + reg);
193	tmp &= ~mask;
194	tmp |= val;
195	writel_relaxed(tmp, ctl->base + reg);
196
197	spin_unlock_irqrestore(&ctl->lock, flags);
198}
199
200static void meson_gpio_irq_init_dummy(struct meson_gpio_irq_controller *ctl)
201{
202}
203
204static void meson8_gpio_irq_sel_pin(struct meson_gpio_irq_controller *ctl,
205				    unsigned int channel, unsigned long hwirq)
206{
207	unsigned int reg_offset;
208	unsigned int bit_offset;
209
210	reg_offset = (channel < 4) ? REG_PIN_03_SEL : REG_PIN_47_SEL;
211	bit_offset = REG_PIN_SEL_SHIFT(channel);
212
213	meson_gpio_irq_update_bits(ctl, reg_offset,
214				   ctl->params->pin_sel_mask << bit_offset,
215				   hwirq << bit_offset);
216}
217
218static void meson_a1_gpio_irq_sel_pin(struct meson_gpio_irq_controller *ctl,
219				      unsigned int channel,
220				      unsigned long hwirq)
221{
222	unsigned int reg_offset;
223	unsigned int bit_offset;
224
225	bit_offset = ((channel % 2) == 0) ? 0 : 16;
226	reg_offset = REG_PIN_A1_SEL + ((channel / 2) << 2);
227
228	meson_gpio_irq_update_bits(ctl, reg_offset,
229				   ctl->params->pin_sel_mask << bit_offset,
230				   hwirq << bit_offset);
231}
232
233/* For a1 or later chips like a1 there is a switch to enable/disable irq */
234static void meson_a1_gpio_irq_init(struct meson_gpio_irq_controller *ctl)
235{
236	meson_gpio_irq_update_bits(ctl, REG_EDGE_POL, BIT(31), BIT(31));
237}
238
239static int
240meson_gpio_irq_request_channel(struct meson_gpio_irq_controller *ctl,
241			       unsigned long  hwirq,
242			       u32 **channel_hwirq)
243{
244	unsigned long flags;
245	unsigned int idx;
246
247	spin_lock_irqsave(&ctl->lock, flags);
248
249	/* Find a free channel */
250	idx = find_first_zero_bit(ctl->channel_map, ctl->params->nr_channels);
251	if (idx >= ctl->params->nr_channels) {
252		spin_unlock_irqrestore(&ctl->lock, flags);
253		pr_err("No channel available\n");
254		return -ENOSPC;
255	}
256
257	/* Mark the channel as used */
258	set_bit(idx, ctl->channel_map);
259
260	spin_unlock_irqrestore(&ctl->lock, flags);
261
262	/*
263	 * Setup the mux of the channel to route the signal of the pad
264	 * to the appropriate input of the GIC
265	 */
266	ctl->params->ops.gpio_irq_sel_pin(ctl, idx, hwirq);
267
268	/*
269	 * Get the hwirq number assigned to this channel through
270	 * a pointer the channel_irq table. The added benefit of this
271	 * method is that we can also retrieve the channel index with
272	 * it, using the table base.
273	 */
274	*channel_hwirq = &(ctl->channel_irqs[idx]);
275
276	pr_debug("hwirq %lu assigned to channel %d - irq %u\n",
277		 hwirq, idx, **channel_hwirq);
278
279	return 0;
280}
281
282static unsigned int
283meson_gpio_irq_get_channel_idx(struct meson_gpio_irq_controller *ctl,
284			       u32 *channel_hwirq)
285{
286	return channel_hwirq - ctl->channel_irqs;
287}
288
289static void
290meson_gpio_irq_release_channel(struct meson_gpio_irq_controller *ctl,
291			       u32 *channel_hwirq)
292{
293	unsigned int idx;
294
295	idx = meson_gpio_irq_get_channel_idx(ctl, channel_hwirq);
296	clear_bit(idx, ctl->channel_map);
297}
298
299static int meson8_gpio_irq_set_type(struct meson_gpio_irq_controller *ctl,
300				    unsigned int type, u32 *channel_hwirq)
301{
302	u32 val = 0;
303	unsigned int idx;
304	const struct meson_gpio_irq_params *params;
305
306	params = ctl->params;
307	idx = meson_gpio_irq_get_channel_idx(ctl, channel_hwirq);
308
309	/*
310	 * The controller has a filter block to operate in either LEVEL or
311	 * EDGE mode, then signal is sent to the GIC. To enable LEVEL_LOW and
312	 * EDGE_FALLING support (which the GIC does not support), the filter
313	 * block is also able to invert the input signal it gets before
314	 * providing it to the GIC.
315	 */
316	type &= IRQ_TYPE_SENSE_MASK;
317
318	/*
319	 * New controller support EDGE_BOTH trigger. This setting takes
320	 * precedence over the other edge/polarity settings
321	 */
322	if (type == IRQ_TYPE_EDGE_BOTH) {
323		if (!params->support_edge_both)
324			return -EINVAL;
325
326		val |= REG_BOTH_EDGE(params, idx);
327	} else {
328		if (type & (IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING))
329			val |= REG_EDGE_POL_EDGE(params, idx);
330
331		if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_EDGE_FALLING))
332			val |= REG_EDGE_POL_LOW(params, idx);
333	}
334
335	meson_gpio_irq_update_bits(ctl, REG_EDGE_POL,
336				   REG_EDGE_POL_MASK(params, idx), val);
337
338	return 0;
339}
340
341/*
342 * gpio irq relative registers for s4
343 * -PADCTRL_GPIO_IRQ_CTRL0
344 * bit[31]:    enable/disable all the irq lines
345 * bit[12-23]: single edge trigger
346 * bit[0-11]:  polarity trigger
347 *
348 * -PADCTRL_GPIO_IRQ_CTRL[X]
349 * bit[0-16]: 7 bits to choose gpio source for irq line 2*[X] - 2
350 * bit[16-22]:7 bits to choose gpio source for irq line 2*[X] - 1
351 * where X = 1-6
352 *
353 * -PADCTRL_GPIO_IRQ_CTRL[7]
354 * bit[0-11]: both edge trigger
355 */
356static int meson_s4_gpio_irq_set_type(struct meson_gpio_irq_controller *ctl,
357				      unsigned int type, u32 *channel_hwirq)
358{
359	u32 val = 0;
360	unsigned int idx;
361
362	idx = meson_gpio_irq_get_channel_idx(ctl, channel_hwirq);
363
364	type &= IRQ_TYPE_SENSE_MASK;
365
366	meson_gpio_irq_update_bits(ctl, REG_EDGE_POL_S4, BIT(idx), 0);
367
368	if (type == IRQ_TYPE_EDGE_BOTH) {
369		val |= BIT(ctl->params->edge_both_offset + idx);
370		meson_gpio_irq_update_bits(ctl, REG_EDGE_POL_S4,
371					   BIT(ctl->params->edge_both_offset + idx), val);
372		return 0;
373	}
374
375	if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_EDGE_FALLING))
376		val |= BIT(ctl->params->pol_low_offset + idx);
377
378	if (type & (IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING))
379		val |= BIT(ctl->params->edge_single_offset + idx);
380
381	meson_gpio_irq_update_bits(ctl, REG_EDGE_POL,
382				   BIT(idx) | BIT(12 + idx), val);
383	return 0;
384};
385
386static unsigned int meson_gpio_irq_type_output(unsigned int type)
387{
388	unsigned int sense = type & IRQ_TYPE_SENSE_MASK;
389
390	type &= ~IRQ_TYPE_SENSE_MASK;
391
392	/*
393	 * The polarity of the signal provided to the GIC should always
394	 * be high.
395	 */
396	if (sense & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
397		type |= IRQ_TYPE_LEVEL_HIGH;
398	else
399		type |= IRQ_TYPE_EDGE_RISING;
400
401	return type;
402}
403
404static int meson_gpio_irq_set_type(struct irq_data *data, unsigned int type)
405{
406	struct meson_gpio_irq_controller *ctl = data->domain->host_data;
407	u32 *channel_hwirq = irq_data_get_irq_chip_data(data);
408	int ret;
409
410	ret = ctl->params->ops.gpio_irq_set_type(ctl, type, channel_hwirq);
411	if (ret)
412		return ret;
413
414	return irq_chip_set_type_parent(data,
415					meson_gpio_irq_type_output(type));
416}
417
418static struct irq_chip meson_gpio_irq_chip = {
419	.name			= "meson-gpio-irqchip",
420	.irq_mask		= irq_chip_mask_parent,
421	.irq_unmask		= irq_chip_unmask_parent,
422	.irq_eoi		= irq_chip_eoi_parent,
423	.irq_set_type		= meson_gpio_irq_set_type,
424	.irq_retrigger		= irq_chip_retrigger_hierarchy,
425#ifdef CONFIG_SMP
426	.irq_set_affinity	= irq_chip_set_affinity_parent,
427#endif
428	.flags			= IRQCHIP_SET_TYPE_MASKED,
429};
430
431static int meson_gpio_irq_domain_translate(struct irq_domain *domain,
432					   struct irq_fwspec *fwspec,
433					   unsigned long *hwirq,
434					   unsigned int *type)
435{
436	if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
437		*hwirq	= fwspec->param[0];
438		*type	= fwspec->param[1];
439		return 0;
440	}
441
442	return -EINVAL;
443}
444
445static int meson_gpio_irq_allocate_gic_irq(struct irq_domain *domain,
446					   unsigned int virq,
447					   u32 hwirq,
448					   unsigned int type)
449{
450	struct irq_fwspec fwspec;
451
452	fwspec.fwnode = domain->parent->fwnode;
453	fwspec.param_count = 3;
454	fwspec.param[0] = 0;	/* SPI */
455	fwspec.param[1] = hwirq;
456	fwspec.param[2] = meson_gpio_irq_type_output(type);
457
458	return irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
459}
460
461static int meson_gpio_irq_domain_alloc(struct irq_domain *domain,
462				       unsigned int virq,
463				       unsigned int nr_irqs,
464				       void *data)
465{
466	struct irq_fwspec *fwspec = data;
467	struct meson_gpio_irq_controller *ctl = domain->host_data;
468	unsigned long hwirq;
469	u32 *channel_hwirq;
470	unsigned int type;
471	int ret;
472
473	if (WARN_ON(nr_irqs != 1))
474		return -EINVAL;
475
476	ret = meson_gpio_irq_domain_translate(domain, fwspec, &hwirq, &type);
477	if (ret)
478		return ret;
479
480	ret = meson_gpio_irq_request_channel(ctl, hwirq, &channel_hwirq);
481	if (ret)
482		return ret;
483
484	ret = meson_gpio_irq_allocate_gic_irq(domain, virq,
485					      *channel_hwirq, type);
486	if (ret < 0) {
487		pr_err("failed to allocate gic irq %u\n", *channel_hwirq);
488		meson_gpio_irq_release_channel(ctl, channel_hwirq);
489		return ret;
490	}
491
492	irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
493				      &meson_gpio_irq_chip, channel_hwirq);
494
495	return 0;
496}
497
498static void meson_gpio_irq_domain_free(struct irq_domain *domain,
499				       unsigned int virq,
500				       unsigned int nr_irqs)
501{
502	struct meson_gpio_irq_controller *ctl = domain->host_data;
503	struct irq_data *irq_data;
504	u32 *channel_hwirq;
505
506	if (WARN_ON(nr_irqs != 1))
507		return;
508
509	irq_domain_free_irqs_parent(domain, virq, 1);
510
511	irq_data = irq_domain_get_irq_data(domain, virq);
512	channel_hwirq = irq_data_get_irq_chip_data(irq_data);
513
514	meson_gpio_irq_release_channel(ctl, channel_hwirq);
515}
516
517static const struct irq_domain_ops meson_gpio_irq_domain_ops = {
518	.alloc		= meson_gpio_irq_domain_alloc,
519	.free		= meson_gpio_irq_domain_free,
520	.translate	= meson_gpio_irq_domain_translate,
521};
522
523static int meson_gpio_irq_parse_dt(struct device_node *node, struct meson_gpio_irq_controller *ctl)
524{
525	const struct of_device_id *match;
526	int ret;
527
528	match = of_match_node(meson_irq_gpio_matches, node);
529	if (!match)
530		return -ENODEV;
531
532	ctl->params = match->data;
533
534	ret = of_property_read_variable_u32_array(node,
535						  "amlogic,channel-interrupts",
536						  ctl->channel_irqs,
537						  ctl->params->nr_channels,
538						  ctl->params->nr_channels);
539	if (ret < 0) {
540		pr_err("can't get %d channel interrupts\n", ctl->params->nr_channels);
541		return ret;
542	}
543
544	ctl->params->ops.gpio_irq_init(ctl);
545
546	return 0;
547}
548
549static int meson_gpio_irq_of_init(struct device_node *node, struct device_node *parent)
550{
551	struct irq_domain *domain, *parent_domain;
552	struct meson_gpio_irq_controller *ctl;
553	int ret;
554
555	if (!parent) {
556		pr_err("missing parent interrupt node\n");
557		return -ENODEV;
558	}
559
560	parent_domain = irq_find_host(parent);
561	if (!parent_domain) {
562		pr_err("unable to obtain parent domain\n");
563		return -ENXIO;
564	}
565
566	ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
567	if (!ctl)
568		return -ENOMEM;
569
570	spin_lock_init(&ctl->lock);
571
572	ctl->base = of_iomap(node, 0);
573	if (!ctl->base) {
574		ret = -ENOMEM;
575		goto free_ctl;
576	}
577
578	ret = meson_gpio_irq_parse_dt(node, ctl);
579	if (ret)
580		goto free_channel_irqs;
581
582	domain = irq_domain_create_hierarchy(parent_domain, 0,
583					     ctl->params->nr_hwirq,
584					     of_node_to_fwnode(node),
585					     &meson_gpio_irq_domain_ops,
586					     ctl);
587	if (!domain) {
588		pr_err("failed to add domain\n");
589		ret = -ENODEV;
590		goto free_channel_irqs;
591	}
592
593	pr_info("%d to %d gpio interrupt mux initialized\n",
594		ctl->params->nr_hwirq, ctl->params->nr_channels);
595
596	return 0;
597
598free_channel_irqs:
599	iounmap(ctl->base);
600free_ctl:
601	kfree(ctl);
602
603	return ret;
604}
605
606IRQCHIP_PLATFORM_DRIVER_BEGIN(meson_gpio_intc)
607IRQCHIP_MATCH("amlogic,meson-gpio-intc", meson_gpio_irq_of_init)
608IRQCHIP_PLATFORM_DRIVER_END(meson_gpio_intc)
609
610MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
611MODULE_LICENSE("GPL v2");
612MODULE_ALIAS("platform:meson-gpio-intc");
613