xref: /openbmc/linux/drivers/irqchip/irq-tegra.c (revision 827634ad)
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/irqdomain.h>
28 #include <linux/of_address.h>
29 #include <linux/slab.h>
30 #include <linux/syscore_ops.h>
31 
32 #include <dt-bindings/interrupt-controller/arm-gic.h>
33 
34 #include "irqchip.h"
35 
36 #define ICTLR_CPU_IEP_VFIQ	0x08
37 #define ICTLR_CPU_IEP_FIR	0x14
38 #define ICTLR_CPU_IEP_FIR_SET	0x18
39 #define ICTLR_CPU_IEP_FIR_CLR	0x1c
40 
41 #define ICTLR_CPU_IER		0x20
42 #define ICTLR_CPU_IER_SET	0x24
43 #define ICTLR_CPU_IER_CLR	0x28
44 #define ICTLR_CPU_IEP_CLASS	0x2C
45 
46 #define ICTLR_COP_IER		0x30
47 #define ICTLR_COP_IER_SET	0x34
48 #define ICTLR_COP_IER_CLR	0x38
49 #define ICTLR_COP_IEP_CLASS	0x3c
50 
51 #define TEGRA_MAX_NUM_ICTLRS	6
52 
53 static unsigned int num_ictlrs;
54 
55 struct tegra_ictlr_soc {
56 	unsigned int num_ictlrs;
57 };
58 
59 static const struct tegra_ictlr_soc tegra20_ictlr_soc = {
60 	.num_ictlrs = 4,
61 };
62 
63 static const struct tegra_ictlr_soc tegra30_ictlr_soc = {
64 	.num_ictlrs = 5,
65 };
66 
67 static const struct tegra_ictlr_soc tegra210_ictlr_soc = {
68 	.num_ictlrs = 6,
69 };
70 
71 static const struct of_device_id ictlr_matches[] = {
72 	{ .compatible = "nvidia,tegra210-ictlr", .data = &tegra210_ictlr_soc },
73 	{ .compatible = "nvidia,tegra30-ictlr", .data = &tegra30_ictlr_soc },
74 	{ .compatible = "nvidia,tegra20-ictlr", .data = &tegra20_ictlr_soc },
75 	{ }
76 };
77 
78 struct tegra_ictlr_info {
79 	void __iomem *base[TEGRA_MAX_NUM_ICTLRS];
80 #ifdef CONFIG_PM_SLEEP
81 	u32 cop_ier[TEGRA_MAX_NUM_ICTLRS];
82 	u32 cop_iep[TEGRA_MAX_NUM_ICTLRS];
83 	u32 cpu_ier[TEGRA_MAX_NUM_ICTLRS];
84 	u32 cpu_iep[TEGRA_MAX_NUM_ICTLRS];
85 
86 	u32 ictlr_wake_mask[TEGRA_MAX_NUM_ICTLRS];
87 #endif
88 };
89 
90 static struct tegra_ictlr_info *lic;
91 
92 static inline void tegra_ictlr_write_mask(struct irq_data *d, unsigned long reg)
93 {
94 	void __iomem *base = d->chip_data;
95 	u32 mask;
96 
97 	mask = BIT(d->hwirq % 32);
98 	writel_relaxed(mask, base + reg);
99 }
100 
101 static void tegra_mask(struct irq_data *d)
102 {
103 	tegra_ictlr_write_mask(d, ICTLR_CPU_IER_CLR);
104 	irq_chip_mask_parent(d);
105 }
106 
107 static void tegra_unmask(struct irq_data *d)
108 {
109 	tegra_ictlr_write_mask(d, ICTLR_CPU_IER_SET);
110 	irq_chip_unmask_parent(d);
111 }
112 
113 static void tegra_eoi(struct irq_data *d)
114 {
115 	tegra_ictlr_write_mask(d, ICTLR_CPU_IEP_FIR_CLR);
116 	irq_chip_eoi_parent(d);
117 }
118 
119 static int tegra_retrigger(struct irq_data *d)
120 {
121 	tegra_ictlr_write_mask(d, ICTLR_CPU_IEP_FIR_SET);
122 	return irq_chip_retrigger_hierarchy(d);
123 }
124 
125 #ifdef CONFIG_PM_SLEEP
126 static int tegra_set_wake(struct irq_data *d, unsigned int enable)
127 {
128 	u32 irq = d->hwirq;
129 	u32 index, mask;
130 
131 	index = (irq / 32);
132 	mask = BIT(irq % 32);
133 	if (enable)
134 		lic->ictlr_wake_mask[index] |= mask;
135 	else
136 		lic->ictlr_wake_mask[index] &= ~mask;
137 
138 	/*
139 	 * Do *not* call into the parent, as the GIC doesn't have any
140 	 * wake-up facility...
141 	 */
142 	return 0;
143 }
144 
145 static int tegra_ictlr_suspend(void)
146 {
147 	unsigned long flags;
148 	unsigned int i;
149 
150 	local_irq_save(flags);
151 	for (i = 0; i < num_ictlrs; i++) {
152 		void __iomem *ictlr = lic->base[i];
153 
154 		/* Save interrupt state */
155 		lic->cpu_ier[i] = readl_relaxed(ictlr + ICTLR_CPU_IER);
156 		lic->cpu_iep[i] = readl_relaxed(ictlr + ICTLR_CPU_IEP_CLASS);
157 		lic->cop_ier[i] = readl_relaxed(ictlr + ICTLR_COP_IER);
158 		lic->cop_iep[i] = readl_relaxed(ictlr + ICTLR_COP_IEP_CLASS);
159 
160 		/* Disable COP interrupts */
161 		writel_relaxed(~0ul, ictlr + ICTLR_COP_IER_CLR);
162 
163 		/* Disable CPU interrupts */
164 		writel_relaxed(~0ul, ictlr + ICTLR_CPU_IER_CLR);
165 
166 		/* Enable the wakeup sources of ictlr */
167 		writel_relaxed(lic->ictlr_wake_mask[i], ictlr + ICTLR_CPU_IER_SET);
168 	}
169 	local_irq_restore(flags);
170 
171 	return 0;
172 }
173 
174 static void tegra_ictlr_resume(void)
175 {
176 	unsigned long flags;
177 	unsigned int i;
178 
179 	local_irq_save(flags);
180 	for (i = 0; i < num_ictlrs; i++) {
181 		void __iomem *ictlr = lic->base[i];
182 
183 		writel_relaxed(lic->cpu_iep[i],
184 			       ictlr + ICTLR_CPU_IEP_CLASS);
185 		writel_relaxed(~0ul, ictlr + ICTLR_CPU_IER_CLR);
186 		writel_relaxed(lic->cpu_ier[i],
187 			       ictlr + ICTLR_CPU_IER_SET);
188 		writel_relaxed(lic->cop_iep[i],
189 			       ictlr + ICTLR_COP_IEP_CLASS);
190 		writel_relaxed(~0ul, ictlr + ICTLR_COP_IER_CLR);
191 		writel_relaxed(lic->cop_ier[i],
192 			       ictlr + ICTLR_COP_IER_SET);
193 	}
194 	local_irq_restore(flags);
195 }
196 
197 static struct syscore_ops tegra_ictlr_syscore_ops = {
198 	.suspend	= tegra_ictlr_suspend,
199 	.resume		= tegra_ictlr_resume,
200 };
201 
202 static void tegra_ictlr_syscore_init(void)
203 {
204 	register_syscore_ops(&tegra_ictlr_syscore_ops);
205 }
206 #else
207 #define tegra_set_wake	NULL
208 static inline void tegra_ictlr_syscore_init(void) {}
209 #endif
210 
211 static struct irq_chip tegra_ictlr_chip = {
212 	.name			= "LIC",
213 	.irq_eoi		= tegra_eoi,
214 	.irq_mask		= tegra_mask,
215 	.irq_unmask		= tegra_unmask,
216 	.irq_retrigger		= tegra_retrigger,
217 	.irq_set_wake		= tegra_set_wake,
218 	.flags			= IRQCHIP_MASK_ON_SUSPEND,
219 #ifdef CONFIG_SMP
220 	.irq_set_affinity	= irq_chip_set_affinity_parent,
221 #endif
222 };
223 
224 static int tegra_ictlr_domain_xlate(struct irq_domain *domain,
225 				    struct device_node *controller,
226 				    const u32 *intspec,
227 				    unsigned int intsize,
228 				    unsigned long *out_hwirq,
229 				    unsigned int *out_type)
230 {
231 	if (domain->of_node != controller)
232 		return -EINVAL;	/* Shouldn't happen, really... */
233 	if (intsize != 3)
234 		return -EINVAL;	/* Not GIC compliant */
235 	if (intspec[0] != GIC_SPI)
236 		return -EINVAL;	/* No PPI should point to this domain */
237 
238 	*out_hwirq = intspec[1];
239 	*out_type = intspec[2];
240 	return 0;
241 }
242 
243 static int tegra_ictlr_domain_alloc(struct irq_domain *domain,
244 				    unsigned int virq,
245 				    unsigned int nr_irqs, void *data)
246 {
247 	struct of_phandle_args *args = data;
248 	struct of_phandle_args parent_args;
249 	struct tegra_ictlr_info *info = domain->host_data;
250 	irq_hw_number_t hwirq;
251 	unsigned int i;
252 
253 	if (args->args_count != 3)
254 		return -EINVAL;	/* Not GIC compliant */
255 	if (args->args[0] != GIC_SPI)
256 		return -EINVAL;	/* No PPI should point to this domain */
257 
258 	hwirq = args->args[1];
259 	if (hwirq >= (num_ictlrs * 32))
260 		return -EINVAL;
261 
262 	for (i = 0; i < nr_irqs; i++) {
263 		int ictlr = (hwirq + i) / 32;
264 
265 		irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
266 					      &tegra_ictlr_chip,
267 					      &info->base[ictlr]);
268 	}
269 
270 	parent_args = *args;
271 	parent_args.np = domain->parent->of_node;
272 	return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &parent_args);
273 }
274 
275 static void tegra_ictlr_domain_free(struct irq_domain *domain,
276 				    unsigned int virq,
277 				    unsigned int nr_irqs)
278 {
279 	unsigned int i;
280 
281 	for (i = 0; i < nr_irqs; i++) {
282 		struct irq_data *d = irq_domain_get_irq_data(domain, virq + i);
283 		irq_domain_reset_irq_data(d);
284 	}
285 }
286 
287 static const struct irq_domain_ops tegra_ictlr_domain_ops = {
288 	.xlate	= tegra_ictlr_domain_xlate,
289 	.alloc	= tegra_ictlr_domain_alloc,
290 	.free	= tegra_ictlr_domain_free,
291 };
292 
293 static int __init tegra_ictlr_init(struct device_node *node,
294 				   struct device_node *parent)
295 {
296 	struct irq_domain *parent_domain, *domain;
297 	const struct of_device_id *match;
298 	const struct tegra_ictlr_soc *soc;
299 	unsigned int i;
300 	int err;
301 
302 	if (!parent) {
303 		pr_err("%s: no parent, giving up\n", node->full_name);
304 		return -ENODEV;
305 	}
306 
307 	parent_domain = irq_find_host(parent);
308 	if (!parent_domain) {
309 		pr_err("%s: unable to obtain parent domain\n", node->full_name);
310 		return -ENXIO;
311 	}
312 
313 	match = of_match_node(ictlr_matches, node);
314 	if (!match)		/* Should never happen... */
315 		return -ENODEV;
316 
317 	soc = match->data;
318 
319 	lic = kzalloc(sizeof(*lic), GFP_KERNEL);
320 	if (!lic)
321 		return -ENOMEM;
322 
323 	for (i = 0; i < TEGRA_MAX_NUM_ICTLRS; i++) {
324 		void __iomem *base;
325 
326 		base = of_iomap(node, i);
327 		if (!base)
328 			break;
329 
330 		lic->base[i] = base;
331 
332 		/* Disable all interrupts */
333 		writel_relaxed(~0UL, base + ICTLR_CPU_IER_CLR);
334 		/* All interrupts target IRQ */
335 		writel_relaxed(0, base + ICTLR_CPU_IEP_CLASS);
336 
337 		num_ictlrs++;
338 	}
339 
340 	if (!num_ictlrs) {
341 		pr_err("%s: no valid regions, giving up\n", node->full_name);
342 		err = -ENOMEM;
343 		goto out_free;
344 	}
345 
346 	WARN(num_ictlrs != soc->num_ictlrs,
347 	     "%s: Found %u interrupt controllers in DT; expected %u.\n",
348 	     node->full_name, num_ictlrs, soc->num_ictlrs);
349 
350 
351 	domain = irq_domain_add_hierarchy(parent_domain, 0, num_ictlrs * 32,
352 					  node, &tegra_ictlr_domain_ops,
353 					  lic);
354 	if (!domain) {
355 		pr_err("%s: failed to allocated domain\n", node->full_name);
356 		err = -ENOMEM;
357 		goto out_unmap;
358 	}
359 
360 	tegra_ictlr_syscore_init();
361 
362 	pr_info("%s: %d interrupts forwarded to %s\n",
363 		node->full_name, num_ictlrs * 32, parent->full_name);
364 
365 	return 0;
366 
367 out_unmap:
368 	for (i = 0; i < num_ictlrs; i++)
369 		iounmap(lic->base[i]);
370 out_free:
371 	kfree(lic);
372 	return err;
373 }
374 
375 IRQCHIP_DECLARE(tegra20_ictlr, "nvidia,tegra20-ictlr", tegra_ictlr_init);
376 IRQCHIP_DECLARE(tegra30_ictlr, "nvidia,tegra30-ictlr", tegra_ictlr_init);
377 IRQCHIP_DECLARE(tegra210_ictlr, "nvidia,tegra210-ictlr", tegra_ictlr_init);
378