xref: /openbmc/linux/drivers/irqchip/irq-tegra.c (revision eb3fcf007fffe5830d815e713591f3e858f2a365)
1 /*
2  * Driver code for Tegra's Legacy Interrupt Controller
3  *
4  * Author: Marc Zyngier <marc.zyngier@arm.com>
5  *
6  * Heavily based on the original arch/arm/mach-tegra/irq.c code:
7  * Copyright (C) 2011 Google, Inc.
8  *
9  * Author:
10  *	Colin Cross <ccross@android.com>
11  *
12  * Copyright (C) 2010,2013, NVIDIA Corporation
13  *
14  * This software is licensed under the terms of the GNU General Public
15  * License version 2, as published by the Free Software Foundation, and
16  * may be copied, distributed, and modified under those terms.
17  *
18  * This program is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  * GNU General Public License for more details.
22  *
23  */
24 
25 #include <linux/io.h>
26 #include <linux/irq.h>
27 #include <linux/irqchip.h>
28 #include <linux/irqdomain.h>
29 #include <linux/of_address.h>
30 #include <linux/slab.h>
31 #include <linux/syscore_ops.h>
32 
33 #include <dt-bindings/interrupt-controller/arm-gic.h>
34 
35 #define ICTLR_CPU_IEP_VFIQ	0x08
36 #define ICTLR_CPU_IEP_FIR	0x14
37 #define ICTLR_CPU_IEP_FIR_SET	0x18
38 #define ICTLR_CPU_IEP_FIR_CLR	0x1c
39 
40 #define ICTLR_CPU_IER		0x20
41 #define ICTLR_CPU_IER_SET	0x24
42 #define ICTLR_CPU_IER_CLR	0x28
43 #define ICTLR_CPU_IEP_CLASS	0x2C
44 
45 #define ICTLR_COP_IER		0x30
46 #define ICTLR_COP_IER_SET	0x34
47 #define ICTLR_COP_IER_CLR	0x38
48 #define ICTLR_COP_IEP_CLASS	0x3c
49 
50 #define TEGRA_MAX_NUM_ICTLRS	6
51 
52 static unsigned int num_ictlrs;
53 
54 struct tegra_ictlr_soc {
55 	unsigned int num_ictlrs;
56 };
57 
58 static const struct tegra_ictlr_soc tegra20_ictlr_soc = {
59 	.num_ictlrs = 4,
60 };
61 
62 static const struct tegra_ictlr_soc tegra30_ictlr_soc = {
63 	.num_ictlrs = 5,
64 };
65 
66 static const struct tegra_ictlr_soc tegra210_ictlr_soc = {
67 	.num_ictlrs = 6,
68 };
69 
70 static const struct of_device_id ictlr_matches[] = {
71 	{ .compatible = "nvidia,tegra210-ictlr", .data = &tegra210_ictlr_soc },
72 	{ .compatible = "nvidia,tegra30-ictlr", .data = &tegra30_ictlr_soc },
73 	{ .compatible = "nvidia,tegra20-ictlr", .data = &tegra20_ictlr_soc },
74 	{ }
75 };
76 
77 struct tegra_ictlr_info {
78 	void __iomem *base[TEGRA_MAX_NUM_ICTLRS];
79 #ifdef CONFIG_PM_SLEEP
80 	u32 cop_ier[TEGRA_MAX_NUM_ICTLRS];
81 	u32 cop_iep[TEGRA_MAX_NUM_ICTLRS];
82 	u32 cpu_ier[TEGRA_MAX_NUM_ICTLRS];
83 	u32 cpu_iep[TEGRA_MAX_NUM_ICTLRS];
84 
85 	u32 ictlr_wake_mask[TEGRA_MAX_NUM_ICTLRS];
86 #endif
87 };
88 
89 static struct tegra_ictlr_info *lic;
90 
91 static inline void tegra_ictlr_write_mask(struct irq_data *d, unsigned long reg)
92 {
93 	void __iomem *base = d->chip_data;
94 	u32 mask;
95 
96 	mask = BIT(d->hwirq % 32);
97 	writel_relaxed(mask, base + reg);
98 }
99 
100 static void tegra_mask(struct irq_data *d)
101 {
102 	tegra_ictlr_write_mask(d, ICTLR_CPU_IER_CLR);
103 	irq_chip_mask_parent(d);
104 }
105 
106 static void tegra_unmask(struct irq_data *d)
107 {
108 	tegra_ictlr_write_mask(d, ICTLR_CPU_IER_SET);
109 	irq_chip_unmask_parent(d);
110 }
111 
112 static void tegra_eoi(struct irq_data *d)
113 {
114 	tegra_ictlr_write_mask(d, ICTLR_CPU_IEP_FIR_CLR);
115 	irq_chip_eoi_parent(d);
116 }
117 
118 static int tegra_retrigger(struct irq_data *d)
119 {
120 	tegra_ictlr_write_mask(d, ICTLR_CPU_IEP_FIR_SET);
121 	return irq_chip_retrigger_hierarchy(d);
122 }
123 
124 #ifdef CONFIG_PM_SLEEP
125 static int tegra_set_wake(struct irq_data *d, unsigned int enable)
126 {
127 	u32 irq = d->hwirq;
128 	u32 index, mask;
129 
130 	index = (irq / 32);
131 	mask = BIT(irq % 32);
132 	if (enable)
133 		lic->ictlr_wake_mask[index] |= mask;
134 	else
135 		lic->ictlr_wake_mask[index] &= ~mask;
136 
137 	/*
138 	 * Do *not* call into the parent, as the GIC doesn't have any
139 	 * wake-up facility...
140 	 */
141 	return 0;
142 }
143 
144 static int tegra_ictlr_suspend(void)
145 {
146 	unsigned long flags;
147 	unsigned int i;
148 
149 	local_irq_save(flags);
150 	for (i = 0; i < num_ictlrs; i++) {
151 		void __iomem *ictlr = lic->base[i];
152 
153 		/* Save interrupt state */
154 		lic->cpu_ier[i] = readl_relaxed(ictlr + ICTLR_CPU_IER);
155 		lic->cpu_iep[i] = readl_relaxed(ictlr + ICTLR_CPU_IEP_CLASS);
156 		lic->cop_ier[i] = readl_relaxed(ictlr + ICTLR_COP_IER);
157 		lic->cop_iep[i] = readl_relaxed(ictlr + ICTLR_COP_IEP_CLASS);
158 
159 		/* Disable COP interrupts */
160 		writel_relaxed(~0ul, ictlr + ICTLR_COP_IER_CLR);
161 
162 		/* Disable CPU interrupts */
163 		writel_relaxed(~0ul, ictlr + ICTLR_CPU_IER_CLR);
164 
165 		/* Enable the wakeup sources of ictlr */
166 		writel_relaxed(lic->ictlr_wake_mask[i], ictlr + ICTLR_CPU_IER_SET);
167 	}
168 	local_irq_restore(flags);
169 
170 	return 0;
171 }
172 
173 static void tegra_ictlr_resume(void)
174 {
175 	unsigned long flags;
176 	unsigned int i;
177 
178 	local_irq_save(flags);
179 	for (i = 0; i < num_ictlrs; i++) {
180 		void __iomem *ictlr = lic->base[i];
181 
182 		writel_relaxed(lic->cpu_iep[i],
183 			       ictlr + ICTLR_CPU_IEP_CLASS);
184 		writel_relaxed(~0ul, ictlr + ICTLR_CPU_IER_CLR);
185 		writel_relaxed(lic->cpu_ier[i],
186 			       ictlr + ICTLR_CPU_IER_SET);
187 		writel_relaxed(lic->cop_iep[i],
188 			       ictlr + ICTLR_COP_IEP_CLASS);
189 		writel_relaxed(~0ul, ictlr + ICTLR_COP_IER_CLR);
190 		writel_relaxed(lic->cop_ier[i],
191 			       ictlr + ICTLR_COP_IER_SET);
192 	}
193 	local_irq_restore(flags);
194 }
195 
196 static struct syscore_ops tegra_ictlr_syscore_ops = {
197 	.suspend	= tegra_ictlr_suspend,
198 	.resume		= tegra_ictlr_resume,
199 };
200 
201 static void tegra_ictlr_syscore_init(void)
202 {
203 	register_syscore_ops(&tegra_ictlr_syscore_ops);
204 }
205 #else
206 #define tegra_set_wake	NULL
207 static inline void tegra_ictlr_syscore_init(void) {}
208 #endif
209 
210 static struct irq_chip tegra_ictlr_chip = {
211 	.name			= "LIC",
212 	.irq_eoi		= tegra_eoi,
213 	.irq_mask		= tegra_mask,
214 	.irq_unmask		= tegra_unmask,
215 	.irq_retrigger		= tegra_retrigger,
216 	.irq_set_wake		= tegra_set_wake,
217 	.flags			= IRQCHIP_MASK_ON_SUSPEND,
218 #ifdef CONFIG_SMP
219 	.irq_set_affinity	= irq_chip_set_affinity_parent,
220 #endif
221 };
222 
223 static int tegra_ictlr_domain_xlate(struct irq_domain *domain,
224 				    struct device_node *controller,
225 				    const u32 *intspec,
226 				    unsigned int intsize,
227 				    unsigned long *out_hwirq,
228 				    unsigned int *out_type)
229 {
230 	if (domain->of_node != controller)
231 		return -EINVAL;	/* Shouldn't happen, really... */
232 	if (intsize != 3)
233 		return -EINVAL;	/* Not GIC compliant */
234 	if (intspec[0] != GIC_SPI)
235 		return -EINVAL;	/* No PPI should point to this domain */
236 
237 	*out_hwirq = intspec[1];
238 	*out_type = intspec[2];
239 	return 0;
240 }
241 
242 static int tegra_ictlr_domain_alloc(struct irq_domain *domain,
243 				    unsigned int virq,
244 				    unsigned int nr_irqs, void *data)
245 {
246 	struct of_phandle_args *args = data;
247 	struct of_phandle_args parent_args;
248 	struct tegra_ictlr_info *info = domain->host_data;
249 	irq_hw_number_t hwirq;
250 	unsigned int i;
251 
252 	if (args->args_count != 3)
253 		return -EINVAL;	/* Not GIC compliant */
254 	if (args->args[0] != GIC_SPI)
255 		return -EINVAL;	/* No PPI should point to this domain */
256 
257 	hwirq = args->args[1];
258 	if (hwirq >= (num_ictlrs * 32))
259 		return -EINVAL;
260 
261 	for (i = 0; i < nr_irqs; i++) {
262 		int ictlr = (hwirq + i) / 32;
263 
264 		irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
265 					      &tegra_ictlr_chip,
266 					      info->base[ictlr]);
267 	}
268 
269 	parent_args = *args;
270 	parent_args.np = domain->parent->of_node;
271 	return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &parent_args);
272 }
273 
274 static void tegra_ictlr_domain_free(struct irq_domain *domain,
275 				    unsigned int virq,
276 				    unsigned int nr_irqs)
277 {
278 	unsigned int i;
279 
280 	for (i = 0; i < nr_irqs; i++) {
281 		struct irq_data *d = irq_domain_get_irq_data(domain, virq + i);
282 		irq_domain_reset_irq_data(d);
283 	}
284 }
285 
286 static const struct irq_domain_ops tegra_ictlr_domain_ops = {
287 	.xlate	= tegra_ictlr_domain_xlate,
288 	.alloc	= tegra_ictlr_domain_alloc,
289 	.free	= tegra_ictlr_domain_free,
290 };
291 
292 static int __init tegra_ictlr_init(struct device_node *node,
293 				   struct device_node *parent)
294 {
295 	struct irq_domain *parent_domain, *domain;
296 	const struct of_device_id *match;
297 	const struct tegra_ictlr_soc *soc;
298 	unsigned int i;
299 	int err;
300 
301 	if (!parent) {
302 		pr_err("%s: no parent, giving up\n", node->full_name);
303 		return -ENODEV;
304 	}
305 
306 	parent_domain = irq_find_host(parent);
307 	if (!parent_domain) {
308 		pr_err("%s: unable to obtain parent domain\n", node->full_name);
309 		return -ENXIO;
310 	}
311 
312 	match = of_match_node(ictlr_matches, node);
313 	if (!match)		/* Should never happen... */
314 		return -ENODEV;
315 
316 	soc = match->data;
317 
318 	lic = kzalloc(sizeof(*lic), GFP_KERNEL);
319 	if (!lic)
320 		return -ENOMEM;
321 
322 	for (i = 0; i < TEGRA_MAX_NUM_ICTLRS; i++) {
323 		void __iomem *base;
324 
325 		base = of_iomap(node, i);
326 		if (!base)
327 			break;
328 
329 		lic->base[i] = base;
330 
331 		/* Disable all interrupts */
332 		writel_relaxed(~0UL, base + ICTLR_CPU_IER_CLR);
333 		/* All interrupts target IRQ */
334 		writel_relaxed(0, base + ICTLR_CPU_IEP_CLASS);
335 
336 		num_ictlrs++;
337 	}
338 
339 	if (!num_ictlrs) {
340 		pr_err("%s: no valid regions, giving up\n", node->full_name);
341 		err = -ENOMEM;
342 		goto out_free;
343 	}
344 
345 	WARN(num_ictlrs != soc->num_ictlrs,
346 	     "%s: Found %u interrupt controllers in DT; expected %u.\n",
347 	     node->full_name, num_ictlrs, soc->num_ictlrs);
348 
349 
350 	domain = irq_domain_add_hierarchy(parent_domain, 0, num_ictlrs * 32,
351 					  node, &tegra_ictlr_domain_ops,
352 					  lic);
353 	if (!domain) {
354 		pr_err("%s: failed to allocated domain\n", node->full_name);
355 		err = -ENOMEM;
356 		goto out_unmap;
357 	}
358 
359 	tegra_ictlr_syscore_init();
360 
361 	pr_info("%s: %d interrupts forwarded to %s\n",
362 		node->full_name, num_ictlrs * 32, parent->full_name);
363 
364 	return 0;
365 
366 out_unmap:
367 	for (i = 0; i < num_ictlrs; i++)
368 		iounmap(lic->base[i]);
369 out_free:
370 	kfree(lic);
371 	return err;
372 }
373 
374 IRQCHIP_DECLARE(tegra20_ictlr, "nvidia,tegra20-ictlr", tegra_ictlr_init);
375 IRQCHIP_DECLARE(tegra30_ictlr, "nvidia,tegra30-ictlr", tegra_ictlr_init);
376 IRQCHIP_DECLARE(tegra210_ictlr, "nvidia,tegra210-ictlr", tegra_ictlr_init);
377