xref: /openbmc/linux/drivers/irqchip/irq-sun6i-r.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * The R_INTC in Allwinner A31 and newer SoCs manages several types of
4  * interrupts, as shown below:
5  *
6  *             NMI IRQ                DIRECT IRQs           MUXED IRQs
7  *              bit 0                  bits 1-15^           bits 19-31
8  *
9  *   +---------+                      +---------+    +---------+  +---------+
10  *   | NMI Pad |                      |  IRQ d  |    |  IRQ m  |  | IRQ m+7 |
11  *   +---------+                      +---------+    +---------+  +---------+
12  *        |                             |     |         |    |      |    |
13  *        |                             |     |         |    |......|    |
14  * +------V------+ +------------+       |     |         | +--V------V--+ |
15  * |   Invert/   | | Write 1 to |       |     |         | |  AND with  | |
16  * | Edge Detect | | PENDING[0] |       |     |         | |  MUX[m/8]  | |
17  * +-------------+ +------------+       |     |         | +------------+ |
18  *            |       |                 |     |         |       |        |
19  *         +--V-------V--+           +--V--+  |      +--V--+    |     +--V--+
20  *         | Set    Reset|           | GIC |  |      | GIC |    |     | GIC |
21  *         |    Latch    |           | SPI |  |      | SPI |... |  ...| SPI |
22  *         +-------------+           | N+d |  |      |  m  |    |     | m+7 |
23  *             |     |               +-----+  |      +-----+    |     +-----+
24  *             |     |                        |                 |
25  *     +-------V-+ +-V----------+   +---------V--+     +--------V--------+
26  *     | GIC SPI | |  AND with  |   |  AND with  |     |    AND with     |
27  *     | N (=32) | |  ENABLE[0] |   |  ENABLE[d] |     |  ENABLE[19+m/8] |
28  *     +---------+ +------------+   +------------+     +-----------------+
29  *                        |                |                    |
30  *                 +------V-----+   +------V-----+     +--------V--------+
31  *                 |    Read    |   |    Read    |     |     Read        |
32  *                 | PENDING[0] |   | PENDING[d] |     | PENDING[19+m/8] |
33  *                 +------------+   +------------+     +-----------------+
34  *
35  * ^ bits 16-18 are direct IRQs for peripherals with banked interrupts, such as
36  *   the MSGBOX. These IRQs do not map to any GIC SPI.
37  *
38  * The H6 variant adds two more (banked) direct IRQs and implements the full
39  * set of 128 mux bits. This requires a second set of top-level registers.
40  */
41 
42 #include <linux/bitmap.h>
43 #include <linux/interrupt.h>
44 #include <linux/irq.h>
45 #include <linux/irqchip.h>
46 #include <linux/irqdomain.h>
47 #include <linux/of.h>
48 #include <linux/of_address.h>
49 #include <linux/of_irq.h>
50 #include <linux/syscore_ops.h>
51 
52 #include <dt-bindings/interrupt-controller/arm-gic.h>
53 
54 #define SUN6I_NMI_CTRL			(0x0c)
55 #define SUN6I_IRQ_PENDING(n)		(0x10 + 4 * (n))
56 #define SUN6I_IRQ_ENABLE(n)		(0x40 + 4 * (n))
57 #define SUN6I_MUX_ENABLE(n)		(0xc0 + 4 * (n))
58 
59 #define SUN6I_NMI_SRC_TYPE_LEVEL_LOW	0
60 #define SUN6I_NMI_SRC_TYPE_EDGE_FALLING	1
61 #define SUN6I_NMI_SRC_TYPE_LEVEL_HIGH	2
62 #define SUN6I_NMI_SRC_TYPE_EDGE_RISING	3
63 
64 #define SUN6I_NMI_BIT			BIT(0)
65 
66 #define SUN6I_NMI_NEEDS_ACK		((void *)1)
67 
68 #define SUN6I_NR_TOP_LEVEL_IRQS		64
69 #define SUN6I_NR_DIRECT_IRQS		16
70 #define SUN6I_NR_MUX_BITS		128
71 
72 struct sun6i_r_intc_variant {
73 	u32		first_mux_irq;
74 	u32		nr_mux_irqs;
75 	u32		mux_valid[BITS_TO_U32(SUN6I_NR_MUX_BITS)];
76 };
77 
78 static void __iomem *base;
79 static irq_hw_number_t nmi_hwirq;
80 static DECLARE_BITMAP(wake_irq_enabled, SUN6I_NR_TOP_LEVEL_IRQS);
81 static DECLARE_BITMAP(wake_mux_enabled, SUN6I_NR_MUX_BITS);
82 static DECLARE_BITMAP(wake_mux_valid, SUN6I_NR_MUX_BITS);
83 
84 static void sun6i_r_intc_ack_nmi(void)
85 {
86 	writel_relaxed(SUN6I_NMI_BIT, base + SUN6I_IRQ_PENDING(0));
87 }
88 
89 static void sun6i_r_intc_nmi_ack(struct irq_data *data)
90 {
91 	if (irqd_get_trigger_type(data) & IRQ_TYPE_EDGE_BOTH)
92 		sun6i_r_intc_ack_nmi();
93 	else
94 		data->chip_data = SUN6I_NMI_NEEDS_ACK;
95 }
96 
97 static void sun6i_r_intc_nmi_eoi(struct irq_data *data)
98 {
99 	/* For oneshot IRQs, delay the ack until the IRQ is unmasked. */
100 	if (data->chip_data == SUN6I_NMI_NEEDS_ACK && !irqd_irq_masked(data)) {
101 		data->chip_data = NULL;
102 		sun6i_r_intc_ack_nmi();
103 	}
104 
105 	irq_chip_eoi_parent(data);
106 }
107 
108 static void sun6i_r_intc_nmi_unmask(struct irq_data *data)
109 {
110 	if (data->chip_data == SUN6I_NMI_NEEDS_ACK) {
111 		data->chip_data = NULL;
112 		sun6i_r_intc_ack_nmi();
113 	}
114 
115 	irq_chip_unmask_parent(data);
116 }
117 
118 static int sun6i_r_intc_nmi_set_type(struct irq_data *data, unsigned int type)
119 {
120 	u32 nmi_src_type;
121 
122 	switch (type) {
123 	case IRQ_TYPE_EDGE_RISING:
124 		nmi_src_type = SUN6I_NMI_SRC_TYPE_EDGE_RISING;
125 		break;
126 	case IRQ_TYPE_EDGE_FALLING:
127 		nmi_src_type = SUN6I_NMI_SRC_TYPE_EDGE_FALLING;
128 		break;
129 	case IRQ_TYPE_LEVEL_HIGH:
130 		nmi_src_type = SUN6I_NMI_SRC_TYPE_LEVEL_HIGH;
131 		break;
132 	case IRQ_TYPE_LEVEL_LOW:
133 		nmi_src_type = SUN6I_NMI_SRC_TYPE_LEVEL_LOW;
134 		break;
135 	default:
136 		return -EINVAL;
137 	}
138 
139 	writel_relaxed(nmi_src_type, base + SUN6I_NMI_CTRL);
140 
141 	/*
142 	 * The "External NMI" GIC input connects to a latch inside R_INTC, not
143 	 * directly to the pin. So the GIC trigger type does not depend on the
144 	 * NMI pin trigger type.
145 	 */
146 	return irq_chip_set_type_parent(data, IRQ_TYPE_LEVEL_HIGH);
147 }
148 
149 static int sun6i_r_intc_nmi_set_irqchip_state(struct irq_data *data,
150 					      enum irqchip_irq_state which,
151 					      bool state)
152 {
153 	if (which == IRQCHIP_STATE_PENDING && !state)
154 		sun6i_r_intc_ack_nmi();
155 
156 	return irq_chip_set_parent_state(data, which, state);
157 }
158 
159 static int sun6i_r_intc_irq_set_wake(struct irq_data *data, unsigned int on)
160 {
161 	unsigned long offset_from_nmi = data->hwirq - nmi_hwirq;
162 
163 	if (offset_from_nmi < SUN6I_NR_DIRECT_IRQS)
164 		assign_bit(offset_from_nmi, wake_irq_enabled, on);
165 	else if (test_bit(data->hwirq, wake_mux_valid))
166 		assign_bit(data->hwirq, wake_mux_enabled, on);
167 	else
168 		/* Not wakeup capable. */
169 		return -EPERM;
170 
171 	return 0;
172 }
173 
174 static struct irq_chip sun6i_r_intc_nmi_chip = {
175 	.name			= "sun6i-r-intc",
176 	.irq_ack		= sun6i_r_intc_nmi_ack,
177 	.irq_mask		= irq_chip_mask_parent,
178 	.irq_unmask		= sun6i_r_intc_nmi_unmask,
179 	.irq_eoi		= sun6i_r_intc_nmi_eoi,
180 	.irq_set_affinity	= irq_chip_set_affinity_parent,
181 	.irq_set_type		= sun6i_r_intc_nmi_set_type,
182 	.irq_set_irqchip_state	= sun6i_r_intc_nmi_set_irqchip_state,
183 	.irq_set_wake		= sun6i_r_intc_irq_set_wake,
184 	.flags			= IRQCHIP_SET_TYPE_MASKED,
185 };
186 
187 static struct irq_chip sun6i_r_intc_wakeup_chip = {
188 	.name			= "sun6i-r-intc",
189 	.irq_mask		= irq_chip_mask_parent,
190 	.irq_unmask		= irq_chip_unmask_parent,
191 	.irq_eoi		= irq_chip_eoi_parent,
192 	.irq_set_affinity	= irq_chip_set_affinity_parent,
193 	.irq_set_type		= irq_chip_set_type_parent,
194 	.irq_set_wake		= sun6i_r_intc_irq_set_wake,
195 	.flags			= IRQCHIP_SET_TYPE_MASKED,
196 };
197 
198 static int sun6i_r_intc_domain_translate(struct irq_domain *domain,
199 					 struct irq_fwspec *fwspec,
200 					 unsigned long *hwirq,
201 					 unsigned int *type)
202 {
203 	/* Accept the old two-cell binding for the NMI only. */
204 	if (fwspec->param_count == 2 && fwspec->param[0] == 0) {
205 		*hwirq = nmi_hwirq;
206 		*type  = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
207 		return 0;
208 	}
209 
210 	/* Otherwise this binding should match the GIC SPI binding. */
211 	if (fwspec->param_count < 3)
212 		return -EINVAL;
213 	if (fwspec->param[0] != GIC_SPI)
214 		return -EINVAL;
215 
216 	*hwirq = fwspec->param[1];
217 	*type  = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
218 
219 	return 0;
220 }
221 
222 static int sun6i_r_intc_domain_alloc(struct irq_domain *domain,
223 				     unsigned int virq,
224 				     unsigned int nr_irqs, void *arg)
225 {
226 	struct irq_fwspec *fwspec = arg;
227 	struct irq_fwspec gic_fwspec;
228 	unsigned long hwirq;
229 	unsigned int type;
230 	int i, ret;
231 
232 	ret = sun6i_r_intc_domain_translate(domain, fwspec, &hwirq, &type);
233 	if (ret)
234 		return ret;
235 	if (hwirq + nr_irqs > SUN6I_NR_MUX_BITS)
236 		return -EINVAL;
237 
238 	/* Construct a GIC-compatible fwspec from this fwspec. */
239 	gic_fwspec = (struct irq_fwspec) {
240 		.fwnode      = domain->parent->fwnode,
241 		.param_count = 3,
242 		.param       = { GIC_SPI, hwirq, type },
243 	};
244 
245 	ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &gic_fwspec);
246 	if (ret)
247 		return ret;
248 
249 	for (i = 0; i < nr_irqs; ++i, ++hwirq, ++virq) {
250 		if (hwirq == nmi_hwirq) {
251 			irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
252 						      &sun6i_r_intc_nmi_chip, 0);
253 			irq_set_handler(virq, handle_fasteoi_ack_irq);
254 		} else {
255 			irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
256 						      &sun6i_r_intc_wakeup_chip, 0);
257 		}
258 	}
259 
260 	return 0;
261 }
262 
263 static const struct irq_domain_ops sun6i_r_intc_domain_ops = {
264 	.translate	= sun6i_r_intc_domain_translate,
265 	.alloc		= sun6i_r_intc_domain_alloc,
266 	.free		= irq_domain_free_irqs_common,
267 };
268 
269 static int sun6i_r_intc_suspend(void)
270 {
271 	u32 buf[BITS_TO_U32(max(SUN6I_NR_TOP_LEVEL_IRQS, SUN6I_NR_MUX_BITS))];
272 	int i;
273 
274 	/* Wake IRQs are enabled during system sleep and shutdown. */
275 	bitmap_to_arr32(buf, wake_irq_enabled, SUN6I_NR_TOP_LEVEL_IRQS);
276 	for (i = 0; i < BITS_TO_U32(SUN6I_NR_TOP_LEVEL_IRQS); ++i)
277 		writel_relaxed(buf[i], base + SUN6I_IRQ_ENABLE(i));
278 	bitmap_to_arr32(buf, wake_mux_enabled, SUN6I_NR_MUX_BITS);
279 	for (i = 0; i < BITS_TO_U32(SUN6I_NR_MUX_BITS); ++i)
280 		writel_relaxed(buf[i], base + SUN6I_MUX_ENABLE(i));
281 
282 	return 0;
283 }
284 
285 static void sun6i_r_intc_resume(void)
286 {
287 	int i;
288 
289 	/* Only the NMI is relevant during normal operation. */
290 	writel_relaxed(SUN6I_NMI_BIT, base + SUN6I_IRQ_ENABLE(0));
291 	for (i = 1; i < BITS_TO_U32(SUN6I_NR_TOP_LEVEL_IRQS); ++i)
292 		writel_relaxed(0, base + SUN6I_IRQ_ENABLE(i));
293 }
294 
295 static void sun6i_r_intc_shutdown(void)
296 {
297 	sun6i_r_intc_suspend();
298 }
299 
300 static struct syscore_ops sun6i_r_intc_syscore_ops = {
301 	.suspend	= sun6i_r_intc_suspend,
302 	.resume		= sun6i_r_intc_resume,
303 	.shutdown	= sun6i_r_intc_shutdown,
304 };
305 
306 static int __init sun6i_r_intc_init(struct device_node *node,
307 				    struct device_node *parent,
308 				    const struct sun6i_r_intc_variant *v)
309 {
310 	struct irq_domain *domain, *parent_domain;
311 	struct of_phandle_args nmi_parent;
312 	int ret;
313 
314 	/* Extract the NMI hwirq number from the OF node. */
315 	ret = of_irq_parse_one(node, 0, &nmi_parent);
316 	if (ret)
317 		return ret;
318 	if (nmi_parent.args_count < 3 ||
319 	    nmi_parent.args[0] != GIC_SPI ||
320 	    nmi_parent.args[2] != IRQ_TYPE_LEVEL_HIGH)
321 		return -EINVAL;
322 	nmi_hwirq = nmi_parent.args[1];
323 
324 	bitmap_set(wake_irq_enabled, v->first_mux_irq, v->nr_mux_irqs);
325 	bitmap_from_arr32(wake_mux_valid, v->mux_valid, SUN6I_NR_MUX_BITS);
326 
327 	parent_domain = irq_find_host(parent);
328 	if (!parent_domain) {
329 		pr_err("%pOF: Failed to obtain parent domain\n", node);
330 		return -ENXIO;
331 	}
332 
333 	base = of_io_request_and_map(node, 0, NULL);
334 	if (IS_ERR(base)) {
335 		pr_err("%pOF: Failed to map MMIO region\n", node);
336 		return PTR_ERR(base);
337 	}
338 
339 	domain = irq_domain_add_hierarchy(parent_domain, 0, 0, node,
340 					  &sun6i_r_intc_domain_ops, NULL);
341 	if (!domain) {
342 		pr_err("%pOF: Failed to allocate domain\n", node);
343 		iounmap(base);
344 		return -ENOMEM;
345 	}
346 
347 	register_syscore_ops(&sun6i_r_intc_syscore_ops);
348 
349 	sun6i_r_intc_ack_nmi();
350 	sun6i_r_intc_resume();
351 
352 	return 0;
353 }
354 
355 static const struct sun6i_r_intc_variant sun6i_a31_r_intc_variant __initconst = {
356 	.first_mux_irq	= 19,
357 	.nr_mux_irqs	= 13,
358 	.mux_valid	= { 0xffffffff, 0xfff80000, 0xffffffff, 0x0000000f },
359 };
360 
361 static int __init sun6i_a31_r_intc_init(struct device_node *node,
362 					struct device_node *parent)
363 {
364 	return sun6i_r_intc_init(node, parent, &sun6i_a31_r_intc_variant);
365 }
366 IRQCHIP_DECLARE(sun6i_a31_r_intc, "allwinner,sun6i-a31-r-intc", sun6i_a31_r_intc_init);
367 
368 static const struct sun6i_r_intc_variant sun50i_h6_r_intc_variant __initconst = {
369 	.first_mux_irq	= 21,
370 	.nr_mux_irqs	= 16,
371 	.mux_valid	= { 0xffffffff, 0xffffffff, 0xffffffff, 0xffffffff },
372 };
373 
374 static int __init sun50i_h6_r_intc_init(struct device_node *node,
375 					struct device_node *parent)
376 {
377 	return sun6i_r_intc_init(node, parent, &sun50i_h6_r_intc_variant);
378 }
379 IRQCHIP_DECLARE(sun50i_h6_r_intc, "allwinner,sun50i-h6-r-intc", sun50i_h6_r_intc_init);
380