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/of.h>
23 #include <linux/of_address.h>
24 #include <linux/of_irq.h>
25 #include <linux/irqdomain.h>
26 #include <linux/err.h>
27 #include <linux/slab.h>
28 #include <linux/io.h>
29 
30 #include <asm/exception.h>
31 #include <asm/mach/irq.h>
32 
33 #include "irq-atmel-aic-common.h"
34 #include "irqchip.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_domain_chip_generic *dgc = aic5_domain->gc;
74 	struct irq_chip_generic *gc = dgc->gc[0];
75 	u32 irqnr;
76 	u32 irqstat;
77 
78 	irqnr = irq_reg_readl(gc->reg_base + AT91_AIC5_IVR);
79 	irqstat = irq_reg_readl(gc->reg_base + AT91_AIC5_ISR);
80 
81 	if (!irqstat)
82 		irq_reg_writel(0, gc->reg_base + AT91_AIC5_EOICR);
83 	else
84 		handle_domain_irq(aic5_domain, irqnr, regs);
85 }
86 
87 static void aic5_mask(struct irq_data *d)
88 {
89 	struct irq_domain *domain = d->domain;
90 	struct irq_domain_chip_generic *dgc = domain->gc;
91 	struct irq_chip_generic *gc = dgc->gc[0];
92 
93 	/* Disable interrupt on AIC5 */
94 	irq_gc_lock(gc);
95 	irq_reg_writel(d->hwirq, gc->reg_base + AT91_AIC5_SSR);
96 	irq_reg_writel(1, gc->reg_base + AT91_AIC5_IDCR);
97 	gc->mask_cache &= ~d->mask;
98 	irq_gc_unlock(gc);
99 }
100 
101 static void aic5_unmask(struct irq_data *d)
102 {
103 	struct irq_domain *domain = d->domain;
104 	struct irq_domain_chip_generic *dgc = domain->gc;
105 	struct irq_chip_generic *gc = dgc->gc[0];
106 
107 	/* Enable interrupt on AIC5 */
108 	irq_gc_lock(gc);
109 	irq_reg_writel(d->hwirq, gc->reg_base + AT91_AIC5_SSR);
110 	irq_reg_writel(1, gc->reg_base + AT91_AIC5_IECR);
111 	gc->mask_cache |= d->mask;
112 	irq_gc_unlock(gc);
113 }
114 
115 static int aic5_retrigger(struct irq_data *d)
116 {
117 	struct irq_domain *domain = d->domain;
118 	struct irq_domain_chip_generic *dgc = domain->gc;
119 	struct irq_chip_generic *gc = dgc->gc[0];
120 
121 	/* Enable interrupt on AIC5 */
122 	irq_gc_lock(gc);
123 	irq_reg_writel(d->hwirq, gc->reg_base + AT91_AIC5_SSR);
124 	irq_reg_writel(1, gc->reg_base + AT91_AIC5_ISCR);
125 	irq_gc_unlock(gc);
126 
127 	return 0;
128 }
129 
130 static int aic5_set_type(struct irq_data *d, unsigned type)
131 {
132 	struct irq_domain *domain = d->domain;
133 	struct irq_domain_chip_generic *dgc = domain->gc;
134 	struct irq_chip_generic *gc = dgc->gc[0];
135 	unsigned int smr;
136 	int ret;
137 
138 	irq_gc_lock(gc);
139 	irq_reg_writel(d->hwirq, gc->reg_base + AT91_AIC5_SSR);
140 	smr = irq_reg_readl(gc->reg_base + AT91_AIC5_SMR);
141 	ret = aic_common_set_type(d, type, &smr);
142 	if (!ret)
143 		irq_reg_writel(smr, gc->reg_base + AT91_AIC5_SMR);
144 	irq_gc_unlock(gc);
145 
146 	return ret;
147 }
148 
149 #ifdef CONFIG_PM
150 static void aic5_suspend(struct irq_data *d)
151 {
152 	struct irq_domain *domain = d->domain;
153 	struct irq_domain_chip_generic *dgc = domain->gc;
154 	struct irq_chip_generic *bgc = dgc->gc[0];
155 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
156 	int i;
157 	u32 mask;
158 
159 	irq_gc_lock(bgc);
160 	for (i = 0; i < dgc->irqs_per_chip; i++) {
161 		mask = 1 << i;
162 		if ((mask & gc->mask_cache) == (mask & gc->wake_active))
163 			continue;
164 
165 		irq_reg_writel(i + gc->irq_base,
166 			       bgc->reg_base + AT91_AIC5_SSR);
167 		if (mask & gc->wake_active)
168 			irq_reg_writel(1, bgc->reg_base + AT91_AIC5_IECR);
169 		else
170 			irq_reg_writel(1, bgc->reg_base + AT91_AIC5_IDCR);
171 	}
172 	irq_gc_unlock(bgc);
173 }
174 
175 static void aic5_resume(struct irq_data *d)
176 {
177 	struct irq_domain *domain = d->domain;
178 	struct irq_domain_chip_generic *dgc = domain->gc;
179 	struct irq_chip_generic *bgc = dgc->gc[0];
180 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
181 	int i;
182 	u32 mask;
183 
184 	irq_gc_lock(bgc);
185 	for (i = 0; i < dgc->irqs_per_chip; i++) {
186 		mask = 1 << i;
187 		if ((mask & gc->mask_cache) == (mask & gc->wake_active))
188 			continue;
189 
190 		irq_reg_writel(i + gc->irq_base,
191 			       bgc->reg_base + AT91_AIC5_SSR);
192 		if (mask & gc->mask_cache)
193 			irq_reg_writel(1, bgc->reg_base + AT91_AIC5_IECR);
194 		else
195 			irq_reg_writel(1, bgc->reg_base + AT91_AIC5_IDCR);
196 	}
197 	irq_gc_unlock(bgc);
198 }
199 
200 static void aic5_pm_shutdown(struct irq_data *d)
201 {
202 	struct irq_domain *domain = d->domain;
203 	struct irq_domain_chip_generic *dgc = domain->gc;
204 	struct irq_chip_generic *bgc = dgc->gc[0];
205 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
206 	int i;
207 
208 	irq_gc_lock(bgc);
209 	for (i = 0; i < dgc->irqs_per_chip; i++) {
210 		irq_reg_writel(i + gc->irq_base,
211 			       bgc->reg_base + AT91_AIC5_SSR);
212 		irq_reg_writel(1, bgc->reg_base + AT91_AIC5_IDCR);
213 		irq_reg_writel(1, bgc->reg_base + 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(0, gc->reg_base + 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(0xffffffff, gc->reg_base + AT91_AIC5_SPU);
241 
242 	/* No debugging in AIC: Debug (Protect) Control Register */
243 	irq_reg_writel(0, gc->reg_base + AT91_AIC5_DCR);
244 
245 	/* Disable and clear all interrupts initially */
246 	for (i = 0; i < domain->revmap_size; i++) {
247 		irq_reg_writel(i, gc->reg_base + AT91_AIC5_SSR);
248 		irq_reg_writel(i, gc->reg_base + AT91_AIC5_SVR);
249 		irq_reg_writel(1, gc->reg_base + AT91_AIC5_IDCR);
250 		irq_reg_writel(1, gc->reg_base + 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_domain_chip_generic *dgc = d->gc;
261 	struct irq_chip_generic *gc;
262 	unsigned smr;
263 	int ret;
264 
265 	if (!dgc)
266 		return -EINVAL;
267 
268 	ret = aic_common_irq_domain_xlate(d, ctrlr, intspec, intsize,
269 					  out_hwirq, out_type);
270 	if (ret)
271 		return ret;
272 
273 	gc = dgc->gc[0];
274 
275 	irq_gc_lock(gc);
276 	irq_reg_writel(*out_hwirq, gc->reg_base + AT91_AIC5_SSR);
277 	smr = irq_reg_readl(gc->reg_base + AT91_AIC5_SMR);
278 	ret = aic_common_set_priority(intspec[2], &smr);
279 	if (!ret)
280 		irq_reg_writel(intspec[2] | smr, gc->reg_base + AT91_AIC5_SMR);
281 	irq_gc_unlock(gc);
282 
283 	return ret;
284 }
285 
286 static const struct irq_domain_ops aic5_irq_ops = {
287 	.map	= irq_map_generic_chip,
288 	.xlate	= aic5_irq_domain_xlate,
289 };
290 
291 static void __init sama5d3_aic_irq_fixup(struct device_node *root)
292 {
293 	aic_common_rtc_irq_fixup(root);
294 }
295 
296 static const struct of_device_id __initdata aic5_irq_fixups[] = {
297 	{ .compatible = "atmel,sama5d3", .data = sama5d3_aic_irq_fixup },
298 	{ .compatible = "atmel,sama5d4", .data = sama5d3_aic_irq_fixup },
299 	{ /* sentinel */ },
300 };
301 
302 static int __init aic5_of_init(struct device_node *node,
303 			       struct device_node *parent,
304 			       int nirqs)
305 {
306 	struct irq_chip_generic *gc;
307 	struct irq_domain *domain;
308 	int nchips;
309 	int i;
310 
311 	if (nirqs > NR_AIC5_IRQS)
312 		return -EINVAL;
313 
314 	if (aic5_domain)
315 		return -EEXIST;
316 
317 	domain = aic_common_of_init(node, &aic5_irq_ops, "atmel-aic5",
318 				    nirqs);
319 	if (IS_ERR(domain))
320 		return PTR_ERR(domain);
321 
322 	aic_common_irq_fixup(aic5_irq_fixups);
323 
324 	aic5_domain = domain;
325 	nchips = aic5_domain->revmap_size / 32;
326 	for (i = 0; i < nchips; i++) {
327 		gc = irq_get_domain_generic_chip(domain, i * 32);
328 
329 		gc->chip_types[0].regs.eoi = AT91_AIC5_EOICR;
330 		gc->chip_types[0].chip.irq_mask = aic5_mask;
331 		gc->chip_types[0].chip.irq_unmask = aic5_unmask;
332 		gc->chip_types[0].chip.irq_retrigger = aic5_retrigger;
333 		gc->chip_types[0].chip.irq_set_type = aic5_set_type;
334 		gc->chip_types[0].chip.irq_suspend = aic5_suspend;
335 		gc->chip_types[0].chip.irq_resume = aic5_resume;
336 		gc->chip_types[0].chip.irq_pm_shutdown = aic5_pm_shutdown;
337 	}
338 
339 	aic5_hw_init(domain);
340 	set_handle_irq(aic5_handle);
341 
342 	return 0;
343 }
344 
345 #define NR_SAMA5D3_IRQS		48
346 
347 static int __init sama5d3_aic5_of_init(struct device_node *node,
348 				       struct device_node *parent)
349 {
350 	return aic5_of_init(node, parent, NR_SAMA5D3_IRQS);
351 }
352 IRQCHIP_DECLARE(sama5d3_aic5, "atmel,sama5d3-aic", sama5d3_aic5_of_init);
353 
354 #define NR_SAMA5D4_IRQS		68
355 
356 static int __init sama5d4_aic5_of_init(struct device_node *node,
357 				       struct device_node *parent)
358 {
359 	return aic5_of_init(node, parent, NR_SAMA5D4_IRQS);
360 }
361 IRQCHIP_DECLARE(sama5d4_aic5, "atmel,sama5d4-aic", sama5d4_aic5_of_init);
362