1 /*
2  * Atmel AT91 AIC5 (Advanced Interrupt Controller) driver
3  *
4  *  Copyright (C) 2004 SAN People
5  *  Copyright (C) 2004 ATMEL
6  *  Copyright (C) Rick Bronson
7  *  Copyright (C) 2014 Free Electrons
8  *
9  *  Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
10  *
11  * This file is licensed under the terms of the GNU General Public
12  * License version 2.  This program is licensed "as is" without any
13  * warranty of any kind, whether express or implied.
14  */
15 
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <linux/mm.h>
19 #include <linux/bitmap.h>
20 #include <linux/types.h>
21 #include <linux/irq.h>
22 #include <linux/irqchip.h>
23 #include <linux/of.h>
24 #include <linux/of_address.h>
25 #include <linux/of_irq.h>
26 #include <linux/irqdomain.h>
27 #include <linux/err.h>
28 #include <linux/slab.h>
29 #include <linux/io.h>
30 
31 #include <asm/exception.h>
32 #include <asm/mach/irq.h>
33 
34 #include "irq-atmel-aic-common.h"
35 
36 /* Number of irq lines managed by AIC */
37 #define NR_AIC5_IRQS	128
38 
39 #define AT91_AIC5_SSR		0x0
40 #define AT91_AIC5_INTSEL_MSK	(0x7f << 0)
41 
42 #define AT91_AIC5_SMR			0x4
43 
44 #define AT91_AIC5_SVR			0x8
45 #define AT91_AIC5_IVR			0x10
46 #define AT91_AIC5_FVR			0x14
47 #define AT91_AIC5_ISR			0x18
48 
49 #define AT91_AIC5_IPR0			0x20
50 #define AT91_AIC5_IPR1			0x24
51 #define AT91_AIC5_IPR2			0x28
52 #define AT91_AIC5_IPR3			0x2c
53 #define AT91_AIC5_IMR			0x30
54 #define AT91_AIC5_CISR			0x34
55 
56 #define AT91_AIC5_IECR			0x40
57 #define AT91_AIC5_IDCR			0x44
58 #define AT91_AIC5_ICCR			0x48
59 #define AT91_AIC5_ISCR			0x4c
60 #define AT91_AIC5_EOICR			0x38
61 #define AT91_AIC5_SPU			0x3c
62 #define AT91_AIC5_DCR			0x6c
63 
64 #define AT91_AIC5_FFER			0x50
65 #define AT91_AIC5_FFDR			0x54
66 #define AT91_AIC5_FFSR			0x58
67 
68 static struct irq_domain *aic5_domain;
69 
70 static asmlinkage void __exception_irq_entry
71 aic5_handle(struct pt_regs *regs)
72 {
73 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(aic5_domain, 0);
74 	u32 irqnr;
75 	u32 irqstat;
76 
77 	irqnr = irq_reg_readl(bgc, AT91_AIC5_IVR);
78 	irqstat = irq_reg_readl(bgc, AT91_AIC5_ISR);
79 
80 	if (!irqstat)
81 		irq_reg_writel(bgc, 0, AT91_AIC5_EOICR);
82 	else
83 		handle_domain_irq(aic5_domain, irqnr, regs);
84 }
85 
86 static void aic5_mask(struct irq_data *d)
87 {
88 	struct irq_domain *domain = d->domain;
89 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
90 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
91 
92 	/*
93 	 * Disable interrupt on AIC5. We always take the lock of the
94 	 * first irq chip as all chips share the same registers.
95 	 */
96 	irq_gc_lock(bgc);
97 	irq_reg_writel(gc, d->hwirq, AT91_AIC5_SSR);
98 	irq_reg_writel(gc, 1, AT91_AIC5_IDCR);
99 	gc->mask_cache &= ~d->mask;
100 	irq_gc_unlock(bgc);
101 }
102 
103 static void aic5_unmask(struct irq_data *d)
104 {
105 	struct irq_domain *domain = d->domain;
106 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
107 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
108 
109 	/*
110 	 * Enable interrupt on AIC5. We always take the lock of the
111 	 * first irq chip as all chips share the same registers.
112 	 */
113 	irq_gc_lock(bgc);
114 	irq_reg_writel(gc, d->hwirq, AT91_AIC5_SSR);
115 	irq_reg_writel(gc, 1, AT91_AIC5_IECR);
116 	gc->mask_cache |= d->mask;
117 	irq_gc_unlock(bgc);
118 }
119 
120 static int aic5_retrigger(struct irq_data *d)
121 {
122 	struct irq_domain *domain = d->domain;
123 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
124 
125 	/* Enable interrupt on AIC5 */
126 	irq_gc_lock(bgc);
127 	irq_reg_writel(bgc, d->hwirq, AT91_AIC5_SSR);
128 	irq_reg_writel(bgc, 1, AT91_AIC5_ISCR);
129 	irq_gc_unlock(bgc);
130 
131 	return 0;
132 }
133 
134 static int aic5_set_type(struct irq_data *d, unsigned type)
135 {
136 	struct irq_domain *domain = d->domain;
137 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
138 	unsigned int smr;
139 	int ret;
140 
141 	irq_gc_lock(bgc);
142 	irq_reg_writel(bgc, d->hwirq, AT91_AIC5_SSR);
143 	smr = irq_reg_readl(bgc, AT91_AIC5_SMR);
144 	ret = aic_common_set_type(d, type, &smr);
145 	if (!ret)
146 		irq_reg_writel(bgc, smr, AT91_AIC5_SMR);
147 	irq_gc_unlock(bgc);
148 
149 	return ret;
150 }
151 
152 #ifdef CONFIG_PM
153 static void aic5_suspend(struct irq_data *d)
154 {
155 	struct irq_domain *domain = d->domain;
156 	struct irq_domain_chip_generic *dgc = domain->gc;
157 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
158 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
159 	int i;
160 	u32 mask;
161 
162 	irq_gc_lock(bgc);
163 	for (i = 0; i < dgc->irqs_per_chip; i++) {
164 		mask = 1 << i;
165 		if ((mask & gc->mask_cache) == (mask & gc->wake_active))
166 			continue;
167 
168 		irq_reg_writel(bgc, i + gc->irq_base, AT91_AIC5_SSR);
169 		if (mask & gc->wake_active)
170 			irq_reg_writel(bgc, 1, AT91_AIC5_IECR);
171 		else
172 			irq_reg_writel(bgc, 1, AT91_AIC5_IDCR);
173 	}
174 	irq_gc_unlock(bgc);
175 }
176 
177 static void aic5_resume(struct irq_data *d)
178 {
179 	struct irq_domain *domain = d->domain;
180 	struct irq_domain_chip_generic *dgc = domain->gc;
181 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
182 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
183 	int i;
184 	u32 mask;
185 
186 	irq_gc_lock(bgc);
187 	for (i = 0; i < dgc->irqs_per_chip; i++) {
188 		mask = 1 << i;
189 		if ((mask & gc->mask_cache) == (mask & gc->wake_active))
190 			continue;
191 
192 		irq_reg_writel(bgc, i + gc->irq_base, AT91_AIC5_SSR);
193 		if (mask & gc->mask_cache)
194 			irq_reg_writel(bgc, 1, AT91_AIC5_IECR);
195 		else
196 			irq_reg_writel(bgc, 1, AT91_AIC5_IDCR);
197 	}
198 	irq_gc_unlock(bgc);
199 }
200 
201 static void aic5_pm_shutdown(struct irq_data *d)
202 {
203 	struct irq_domain *domain = d->domain;
204 	struct irq_domain_chip_generic *dgc = domain->gc;
205 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
206 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
207 	int i;
208 
209 	irq_gc_lock(bgc);
210 	for (i = 0; i < dgc->irqs_per_chip; i++) {
211 		irq_reg_writel(bgc, i + gc->irq_base, AT91_AIC5_SSR);
212 		irq_reg_writel(bgc, 1, AT91_AIC5_IDCR);
213 		irq_reg_writel(bgc, 1, AT91_AIC5_ICCR);
214 	}
215 	irq_gc_unlock(bgc);
216 }
217 #else
218 #define aic5_suspend		NULL
219 #define aic5_resume		NULL
220 #define aic5_pm_shutdown	NULL
221 #endif /* CONFIG_PM */
222 
223 static void __init aic5_hw_init(struct irq_domain *domain)
224 {
225 	struct irq_chip_generic *gc = irq_get_domain_generic_chip(domain, 0);
226 	int i;
227 
228 	/*
229 	 * Perform 8 End Of Interrupt Command to make sure AIC
230 	 * will not Lock out nIRQ
231 	 */
232 	for (i = 0; i < 8; i++)
233 		irq_reg_writel(gc, 0, AT91_AIC5_EOICR);
234 
235 	/*
236 	 * Spurious Interrupt ID in Spurious Vector Register.
237 	 * When there is no current interrupt, the IRQ Vector Register
238 	 * reads the value stored in AIC_SPU
239 	 */
240 	irq_reg_writel(gc, 0xffffffff, AT91_AIC5_SPU);
241 
242 	/* No debugging in AIC: Debug (Protect) Control Register */
243 	irq_reg_writel(gc, 0, AT91_AIC5_DCR);
244 
245 	/* Disable and clear all interrupts initially */
246 	for (i = 0; i < domain->revmap_size; i++) {
247 		irq_reg_writel(gc, i, AT91_AIC5_SSR);
248 		irq_reg_writel(gc, i, AT91_AIC5_SVR);
249 		irq_reg_writel(gc, 1, AT91_AIC5_IDCR);
250 		irq_reg_writel(gc, 1, AT91_AIC5_ICCR);
251 	}
252 }
253 
254 static int aic5_irq_domain_xlate(struct irq_domain *d,
255 				 struct device_node *ctrlr,
256 				 const u32 *intspec, unsigned int intsize,
257 				 irq_hw_number_t *out_hwirq,
258 				 unsigned int *out_type)
259 {
260 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(d, 0);
261 	unsigned smr;
262 	int ret;
263 
264 	if (!bgc)
265 		return -EINVAL;
266 
267 	ret = aic_common_irq_domain_xlate(d, ctrlr, intspec, intsize,
268 					  out_hwirq, out_type);
269 	if (ret)
270 		return ret;
271 
272 	irq_gc_lock(bgc);
273 	irq_reg_writel(bgc, *out_hwirq, AT91_AIC5_SSR);
274 	smr = irq_reg_readl(bgc, AT91_AIC5_SMR);
275 	aic_common_set_priority(intspec[2], &smr);
276 	irq_reg_writel(bgc, smr, AT91_AIC5_SMR);
277 	irq_gc_unlock(bgc);
278 
279 	return ret;
280 }
281 
282 static const struct irq_domain_ops aic5_irq_ops = {
283 	.map	= irq_map_generic_chip,
284 	.xlate	= aic5_irq_domain_xlate,
285 };
286 
287 static void __init sama5d3_aic_irq_fixup(struct device_node *root)
288 {
289 	aic_common_rtc_irq_fixup(root);
290 }
291 
292 static const struct of_device_id aic5_irq_fixups[] __initconst = {
293 	{ .compatible = "atmel,sama5d3", .data = sama5d3_aic_irq_fixup },
294 	{ .compatible = "atmel,sama5d4", .data = sama5d3_aic_irq_fixup },
295 	{ /* sentinel */ },
296 };
297 
298 static int __init aic5_of_init(struct device_node *node,
299 			       struct device_node *parent,
300 			       int nirqs)
301 {
302 	struct irq_chip_generic *gc;
303 	struct irq_domain *domain;
304 	int nchips;
305 	int i;
306 
307 	if (nirqs > NR_AIC5_IRQS)
308 		return -EINVAL;
309 
310 	if (aic5_domain)
311 		return -EEXIST;
312 
313 	domain = aic_common_of_init(node, &aic5_irq_ops, "atmel-aic5",
314 				    nirqs, aic5_irq_fixups);
315 	if (IS_ERR(domain))
316 		return PTR_ERR(domain);
317 
318 	aic5_domain = domain;
319 	nchips = aic5_domain->revmap_size / 32;
320 	for (i = 0; i < nchips; i++) {
321 		gc = irq_get_domain_generic_chip(domain, i * 32);
322 
323 		gc->chip_types[0].regs.eoi = AT91_AIC5_EOICR;
324 		gc->chip_types[0].chip.irq_mask = aic5_mask;
325 		gc->chip_types[0].chip.irq_unmask = aic5_unmask;
326 		gc->chip_types[0].chip.irq_retrigger = aic5_retrigger;
327 		gc->chip_types[0].chip.irq_set_type = aic5_set_type;
328 		gc->chip_types[0].chip.irq_suspend = aic5_suspend;
329 		gc->chip_types[0].chip.irq_resume = aic5_resume;
330 		gc->chip_types[0].chip.irq_pm_shutdown = aic5_pm_shutdown;
331 	}
332 
333 	aic5_hw_init(domain);
334 	set_handle_irq(aic5_handle);
335 
336 	return 0;
337 }
338 
339 #define NR_SAMA5D2_IRQS		77
340 
341 static int __init sama5d2_aic5_of_init(struct device_node *node,
342 				       struct device_node *parent)
343 {
344 	return aic5_of_init(node, parent, NR_SAMA5D2_IRQS);
345 }
346 IRQCHIP_DECLARE(sama5d2_aic5, "atmel,sama5d2-aic", sama5d2_aic5_of_init);
347 
348 #define NR_SAMA5D3_IRQS		48
349 
350 static int __init sama5d3_aic5_of_init(struct device_node *node,
351 				       struct device_node *parent)
352 {
353 	return aic5_of_init(node, parent, NR_SAMA5D3_IRQS);
354 }
355 IRQCHIP_DECLARE(sama5d3_aic5, "atmel,sama5d3-aic", sama5d3_aic5_of_init);
356 
357 #define NR_SAMA5D4_IRQS		68
358 
359 static int __init sama5d4_aic5_of_init(struct device_node *node,
360 				       struct device_node *parent)
361 {
362 	return aic5_of_init(node, parent, NR_SAMA5D4_IRQS);
363 }
364 IRQCHIP_DECLARE(sama5d4_aic5, "atmel,sama5d4-aic", sama5d4_aic5_of_init);
365