xref: /openbmc/linux/drivers/irqchip/irq-tegra.c (revision 7f6964c5)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Driver code for Tegra's Legacy Interrupt Controller
4  *
5  * Author: Marc Zyngier <marc.zyngier@arm.com>
6  *
7  * Heavily based on the original arch/arm/mach-tegra/irq.c code:
8  * Copyright (C) 2011 Google, Inc.
9  *
10  * Author:
11  *	Colin Cross <ccross@android.com>
12  *
13  * Copyright (C) 2010,2013, NVIDIA Corporation
14  */
15 
16 #include <linux/io.h>
17 #include <linux/irq.h>
18 #include <linux/irqchip.h>
19 #include <linux/irqdomain.h>
20 #include <linux/of_address.h>
21 #include <linux/slab.h>
22 #include <linux/syscore_ops.h>
23 
24 #include <dt-bindings/interrupt-controller/arm-gic.h>
25 
26 #define ICTLR_CPU_IEP_VFIQ	0x08
27 #define ICTLR_CPU_IEP_FIR	0x14
28 #define ICTLR_CPU_IEP_FIR_SET	0x18
29 #define ICTLR_CPU_IEP_FIR_CLR	0x1c
30 
31 #define ICTLR_CPU_IER		0x20
32 #define ICTLR_CPU_IER_SET	0x24
33 #define ICTLR_CPU_IER_CLR	0x28
34 #define ICTLR_CPU_IEP_CLASS	0x2C
35 
36 #define ICTLR_COP_IER		0x30
37 #define ICTLR_COP_IER_SET	0x34
38 #define ICTLR_COP_IER_CLR	0x38
39 #define ICTLR_COP_IEP_CLASS	0x3c
40 
41 #define TEGRA_MAX_NUM_ICTLRS	6
42 
43 static unsigned int num_ictlrs;
44 
45 struct tegra_ictlr_soc {
46 	unsigned int num_ictlrs;
47 };
48 
49 static const struct tegra_ictlr_soc tegra20_ictlr_soc = {
50 	.num_ictlrs = 4,
51 };
52 
53 static const struct tegra_ictlr_soc tegra30_ictlr_soc = {
54 	.num_ictlrs = 5,
55 };
56 
57 static const struct tegra_ictlr_soc tegra210_ictlr_soc = {
58 	.num_ictlrs = 6,
59 };
60 
61 static const struct of_device_id ictlr_matches[] = {
62 	{ .compatible = "nvidia,tegra210-ictlr", .data = &tegra210_ictlr_soc },
63 	{ .compatible = "nvidia,tegra30-ictlr", .data = &tegra30_ictlr_soc },
64 	{ .compatible = "nvidia,tegra20-ictlr", .data = &tegra20_ictlr_soc },
65 	{ }
66 };
67 
68 struct tegra_ictlr_info {
69 	void __iomem *base[TEGRA_MAX_NUM_ICTLRS];
70 #ifdef CONFIG_PM_SLEEP
71 	u32 cop_ier[TEGRA_MAX_NUM_ICTLRS];
72 	u32 cop_iep[TEGRA_MAX_NUM_ICTLRS];
73 	u32 cpu_ier[TEGRA_MAX_NUM_ICTLRS];
74 	u32 cpu_iep[TEGRA_MAX_NUM_ICTLRS];
75 
76 	u32 ictlr_wake_mask[TEGRA_MAX_NUM_ICTLRS];
77 #endif
78 };
79 
80 static struct tegra_ictlr_info *lic;
81 
82 static inline void tegra_ictlr_write_mask(struct irq_data *d, unsigned long reg)
83 {
84 	void __iomem *base = (void __iomem __force *)d->chip_data;
85 	u32 mask;
86 
87 	mask = BIT(d->hwirq % 32);
88 	writel_relaxed(mask, base + reg);
89 }
90 
91 static void tegra_mask(struct irq_data *d)
92 {
93 	tegra_ictlr_write_mask(d, ICTLR_CPU_IER_CLR);
94 	irq_chip_mask_parent(d);
95 }
96 
97 static void tegra_unmask(struct irq_data *d)
98 {
99 	tegra_ictlr_write_mask(d, ICTLR_CPU_IER_SET);
100 	irq_chip_unmask_parent(d);
101 }
102 
103 static void tegra_eoi(struct irq_data *d)
104 {
105 	tegra_ictlr_write_mask(d, ICTLR_CPU_IEP_FIR_CLR);
106 	irq_chip_eoi_parent(d);
107 }
108 
109 static int tegra_retrigger(struct irq_data *d)
110 {
111 	tegra_ictlr_write_mask(d, ICTLR_CPU_IEP_FIR_SET);
112 	return irq_chip_retrigger_hierarchy(d);
113 }
114 
115 #ifdef CONFIG_PM_SLEEP
116 static int tegra_set_wake(struct irq_data *d, unsigned int enable)
117 {
118 	u32 irq = d->hwirq;
119 	u32 index, mask;
120 
121 	index = (irq / 32);
122 	mask = BIT(irq % 32);
123 	if (enable)
124 		lic->ictlr_wake_mask[index] |= mask;
125 	else
126 		lic->ictlr_wake_mask[index] &= ~mask;
127 
128 	/*
129 	 * Do *not* call into the parent, as the GIC doesn't have any
130 	 * wake-up facility...
131 	 */
132 	return 0;
133 }
134 
135 static int tegra_ictlr_suspend(void)
136 {
137 	unsigned long flags;
138 	unsigned int i;
139 
140 	local_irq_save(flags);
141 	for (i = 0; i < num_ictlrs; i++) {
142 		void __iomem *ictlr = lic->base[i];
143 
144 		/* Save interrupt state */
145 		lic->cpu_ier[i] = readl_relaxed(ictlr + ICTLR_CPU_IER);
146 		lic->cpu_iep[i] = readl_relaxed(ictlr + ICTLR_CPU_IEP_CLASS);
147 		lic->cop_ier[i] = readl_relaxed(ictlr + ICTLR_COP_IER);
148 		lic->cop_iep[i] = readl_relaxed(ictlr + ICTLR_COP_IEP_CLASS);
149 
150 		/* Disable COP interrupts */
151 		writel_relaxed(~0ul, ictlr + ICTLR_COP_IER_CLR);
152 
153 		/* Disable CPU interrupts */
154 		writel_relaxed(~0ul, ictlr + ICTLR_CPU_IER_CLR);
155 
156 		/* Enable the wakeup sources of ictlr */
157 		writel_relaxed(lic->ictlr_wake_mask[i], ictlr + ICTLR_CPU_IER_SET);
158 	}
159 	local_irq_restore(flags);
160 
161 	return 0;
162 }
163 
164 static void tegra_ictlr_resume(void)
165 {
166 	unsigned long flags;
167 	unsigned int i;
168 
169 	local_irq_save(flags);
170 	for (i = 0; i < num_ictlrs; i++) {
171 		void __iomem *ictlr = lic->base[i];
172 
173 		writel_relaxed(lic->cpu_iep[i],
174 			       ictlr + ICTLR_CPU_IEP_CLASS);
175 		writel_relaxed(~0ul, ictlr + ICTLR_CPU_IER_CLR);
176 		writel_relaxed(lic->cpu_ier[i],
177 			       ictlr + ICTLR_CPU_IER_SET);
178 		writel_relaxed(lic->cop_iep[i],
179 			       ictlr + ICTLR_COP_IEP_CLASS);
180 		writel_relaxed(~0ul, ictlr + ICTLR_COP_IER_CLR);
181 		writel_relaxed(lic->cop_ier[i],
182 			       ictlr + ICTLR_COP_IER_SET);
183 	}
184 	local_irq_restore(flags);
185 }
186 
187 static struct syscore_ops tegra_ictlr_syscore_ops = {
188 	.suspend	= tegra_ictlr_suspend,
189 	.resume		= tegra_ictlr_resume,
190 };
191 
192 static void tegra_ictlr_syscore_init(void)
193 {
194 	register_syscore_ops(&tegra_ictlr_syscore_ops);
195 }
196 #else
197 #define tegra_set_wake	NULL
198 static inline void tegra_ictlr_syscore_init(void) {}
199 #endif
200 
201 static struct irq_chip tegra_ictlr_chip = {
202 	.name			= "LIC",
203 	.irq_eoi		= tegra_eoi,
204 	.irq_mask		= tegra_mask,
205 	.irq_unmask		= tegra_unmask,
206 	.irq_retrigger		= tegra_retrigger,
207 	.irq_set_wake		= tegra_set_wake,
208 	.irq_set_type		= irq_chip_set_type_parent,
209 	.flags			= IRQCHIP_MASK_ON_SUSPEND,
210 #ifdef CONFIG_SMP
211 	.irq_set_affinity	= irq_chip_set_affinity_parent,
212 #endif
213 };
214 
215 static int tegra_ictlr_domain_translate(struct irq_domain *d,
216 					struct irq_fwspec *fwspec,
217 					unsigned long *hwirq,
218 					unsigned int *type)
219 {
220 	if (is_of_node(fwspec->fwnode)) {
221 		if (fwspec->param_count != 3)
222 			return -EINVAL;
223 
224 		/* No PPI should point to this domain */
225 		if (fwspec->param[0] != 0)
226 			return -EINVAL;
227 
228 		*hwirq = fwspec->param[1];
229 		*type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
230 		return 0;
231 	}
232 
233 	return -EINVAL;
234 }
235 
236 static int tegra_ictlr_domain_alloc(struct irq_domain *domain,
237 				    unsigned int virq,
238 				    unsigned int nr_irqs, void *data)
239 {
240 	struct irq_fwspec *fwspec = data;
241 	struct irq_fwspec parent_fwspec;
242 	struct tegra_ictlr_info *info = domain->host_data;
243 	irq_hw_number_t hwirq;
244 	unsigned int i;
245 
246 	if (fwspec->param_count != 3)
247 		return -EINVAL;	/* Not GIC compliant */
248 	if (fwspec->param[0] != GIC_SPI)
249 		return -EINVAL;	/* No PPI should point to this domain */
250 
251 	hwirq = fwspec->param[1];
252 	if (hwirq >= (num_ictlrs * 32))
253 		return -EINVAL;
254 
255 	for (i = 0; i < nr_irqs; i++) {
256 		int ictlr = (hwirq + i) / 32;
257 
258 		irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
259 					      &tegra_ictlr_chip,
260 					      (void __force *)info->base[ictlr]);
261 	}
262 
263 	parent_fwspec = *fwspec;
264 	parent_fwspec.fwnode = domain->parent->fwnode;
265 	return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
266 					    &parent_fwspec);
267 }
268 
269 static const struct irq_domain_ops tegra_ictlr_domain_ops = {
270 	.translate	= tegra_ictlr_domain_translate,
271 	.alloc		= tegra_ictlr_domain_alloc,
272 	.free		= irq_domain_free_irqs_common,
273 };
274 
275 static int __init tegra_ictlr_init(struct device_node *node,
276 				   struct device_node *parent)
277 {
278 	struct irq_domain *parent_domain, *domain;
279 	const struct of_device_id *match;
280 	const struct tegra_ictlr_soc *soc;
281 	unsigned int i;
282 	int err;
283 
284 	if (!parent) {
285 		pr_err("%pOF: no parent, giving up\n", node);
286 		return -ENODEV;
287 	}
288 
289 	parent_domain = irq_find_host(parent);
290 	if (!parent_domain) {
291 		pr_err("%pOF: unable to obtain parent domain\n", node);
292 		return -ENXIO;
293 	}
294 
295 	match = of_match_node(ictlr_matches, node);
296 	if (!match)		/* Should never happen... */
297 		return -ENODEV;
298 
299 	soc = match->data;
300 
301 	lic = kzalloc(sizeof(*lic), GFP_KERNEL);
302 	if (!lic)
303 		return -ENOMEM;
304 
305 	for (i = 0; i < TEGRA_MAX_NUM_ICTLRS; i++) {
306 		void __iomem *base;
307 
308 		base = of_iomap(node, i);
309 		if (!base)
310 			break;
311 
312 		lic->base[i] = base;
313 
314 		/* Disable all interrupts */
315 		writel_relaxed(~0UL, base + ICTLR_CPU_IER_CLR);
316 		/* All interrupts target IRQ */
317 		writel_relaxed(0, base + ICTLR_CPU_IEP_CLASS);
318 
319 		num_ictlrs++;
320 	}
321 
322 	if (!num_ictlrs) {
323 		pr_err("%pOF: no valid regions, giving up\n", node);
324 		err = -ENOMEM;
325 		goto out_free;
326 	}
327 
328 	WARN(num_ictlrs != soc->num_ictlrs,
329 	     "%pOF: Found %u interrupt controllers in DT; expected %u.\n",
330 	     node, num_ictlrs, soc->num_ictlrs);
331 
332 
333 	domain = irq_domain_add_hierarchy(parent_domain, 0, num_ictlrs * 32,
334 					  node, &tegra_ictlr_domain_ops,
335 					  lic);
336 	if (!domain) {
337 		pr_err("%pOF: failed to allocated domain\n", node);
338 		err = -ENOMEM;
339 		goto out_unmap;
340 	}
341 
342 	tegra_ictlr_syscore_init();
343 
344 	pr_info("%pOF: %d interrupts forwarded to %pOF\n",
345 		node, num_ictlrs * 32, parent);
346 
347 	return 0;
348 
349 out_unmap:
350 	for (i = 0; i < num_ictlrs; i++)
351 		iounmap(lic->base[i]);
352 out_free:
353 	kfree(lic);
354 	return err;
355 }
356 
357 IRQCHIP_DECLARE(tegra20_ictlr, "nvidia,tegra20-ictlr", tegra_ictlr_init);
358 IRQCHIP_DECLARE(tegra30_ictlr, "nvidia,tegra30-ictlr", tegra_ictlr_init);
359 IRQCHIP_DECLARE(tegra210_ictlr, "nvidia,tegra210-ictlr", tegra_ictlr_init);
360