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 void __exception_irq_entry aic5_handle(struct pt_regs *regs)
71 {
72 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(aic5_domain, 0);
73 	u32 irqnr;
74 	u32 irqstat;
75 
76 	irqnr = irq_reg_readl(bgc, AT91_AIC5_IVR);
77 	irqstat = irq_reg_readl(bgc, AT91_AIC5_ISR);
78 
79 	if (!irqstat)
80 		irq_reg_writel(bgc, 0, AT91_AIC5_EOICR);
81 	else
82 		generic_handle_domain_irq(aic5_domain, irqnr);
83 }
84 
85 static void aic5_mask(struct irq_data *d)
86 {
87 	struct irq_domain *domain = d->domain;
88 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
89 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
90 
91 	/*
92 	 * Disable interrupt on AIC5. We always take the lock of the
93 	 * first irq chip as all chips share the same registers.
94 	 */
95 	guard(raw_spinlock)(&bgc->lock);
96 	irq_reg_writel(gc, d->hwirq, AT91_AIC5_SSR);
97 	irq_reg_writel(gc, 1, AT91_AIC5_IDCR);
98 	gc->mask_cache &= ~d->mask;
99 }
100 
101 static void aic5_unmask(struct irq_data *d)
102 {
103 	struct irq_domain *domain = d->domain;
104 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
105 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
106 
107 	/*
108 	 * Enable interrupt on AIC5. We always take the lock of the
109 	 * first irq chip as all chips share the same registers.
110 	 */
111 	guard(raw_spinlock)(&bgc->lock);
112 	irq_reg_writel(gc, d->hwirq, AT91_AIC5_SSR);
113 	irq_reg_writel(gc, 1, AT91_AIC5_IECR);
114 	gc->mask_cache |= d->mask;
115 }
116 
117 static int aic5_retrigger(struct irq_data *d)
118 {
119 	struct irq_domain *domain = d->domain;
120 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
121 
122 	/* Enable interrupt on AIC5 */
123 	guard(raw_spinlock)(&bgc->lock);
124 	irq_reg_writel(bgc, d->hwirq, AT91_AIC5_SSR);
125 	irq_reg_writel(bgc, 1, AT91_AIC5_ISCR);
126 	return 1;
127 }
128 
129 static int aic5_set_type(struct irq_data *d, unsigned type)
130 {
131 	struct irq_domain *domain = d->domain;
132 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
133 	unsigned int smr;
134 	int ret;
135 
136 	guard(raw_spinlock)(&bgc->lock);
137 	irq_reg_writel(bgc, d->hwirq, AT91_AIC5_SSR);
138 	smr = irq_reg_readl(bgc, AT91_AIC5_SMR);
139 	ret = aic_common_set_type(d, type, &smr);
140 	if (!ret)
141 		irq_reg_writel(bgc, smr, AT91_AIC5_SMR);
142 	return ret;
143 }
144 
145 #ifdef CONFIG_PM
146 static u32 *smr_cache;
147 
148 static void aic5_suspend(struct irq_data *d)
149 {
150 	struct irq_domain *domain = d->domain;
151 	struct irq_domain_chip_generic *dgc = domain->gc;
152 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
153 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
154 	int i;
155 	u32 mask;
156 
157 	if (smr_cache)
158 		for (i = 0; i < domain->revmap_size; i++) {
159 			irq_reg_writel(bgc, i, AT91_AIC5_SSR);
160 			smr_cache[i] = irq_reg_readl(bgc, AT91_AIC5_SMR);
161 		}
162 
163 	guard(raw_spinlock)(&bgc->lock);
164 	for (i = 0; i < dgc->irqs_per_chip; i++) {
165 		mask = 1 << i;
166 		if ((mask & gc->mask_cache) == (mask & gc->wake_active))
167 			continue;
168 
169 		irq_reg_writel(bgc, i + gc->irq_base, AT91_AIC5_SSR);
170 		if (mask & gc->wake_active)
171 			irq_reg_writel(bgc, 1, AT91_AIC5_IECR);
172 		else
173 			irq_reg_writel(bgc, 1, AT91_AIC5_IDCR);
174 	}
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 	guard(raw_spinlock)(&bgc->lock);
187 
188 	if (smr_cache) {
189 		irq_reg_writel(bgc, 0xffffffff, AT91_AIC5_SPU);
190 		for (i = 0; i < domain->revmap_size; i++) {
191 			irq_reg_writel(bgc, i, AT91_AIC5_SSR);
192 			irq_reg_writel(bgc, i, AT91_AIC5_SVR);
193 			irq_reg_writel(bgc, smr_cache[i], AT91_AIC5_SMR);
194 		}
195 	}
196 
197 	for (i = 0; i < dgc->irqs_per_chip; i++) {
198 		mask = 1 << i;
199 
200 		if (!smr_cache &&
201 		    ((mask & gc->mask_cache) == (mask & gc->wake_active)))
202 			continue;
203 
204 		irq_reg_writel(bgc, i + gc->irq_base, AT91_AIC5_SSR);
205 		if (mask & gc->mask_cache)
206 			irq_reg_writel(bgc, 1, AT91_AIC5_IECR);
207 		else
208 			irq_reg_writel(bgc, 1, AT91_AIC5_IDCR);
209 	}
210 }
211 
212 static void aic5_pm_shutdown(struct irq_data *d)
213 {
214 	struct irq_domain *domain = d->domain;
215 	struct irq_domain_chip_generic *dgc = domain->gc;
216 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
217 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
218 	int i;
219 
220 	guard(raw_spinlock)(&bgc->lock);
221 	for (i = 0; i < dgc->irqs_per_chip; i++) {
222 		irq_reg_writel(bgc, i + gc->irq_base, AT91_AIC5_SSR);
223 		irq_reg_writel(bgc, 1, AT91_AIC5_IDCR);
224 		irq_reg_writel(bgc, 1, AT91_AIC5_ICCR);
225 	}
226 }
227 #else
228 #define aic5_suspend		NULL
229 #define aic5_resume		NULL
230 #define aic5_pm_shutdown	NULL
231 #endif /* CONFIG_PM */
232 
233 static void __init aic5_hw_init(struct irq_domain *domain)
234 {
235 	struct irq_chip_generic *gc = irq_get_domain_generic_chip(domain, 0);
236 	int i;
237 
238 	/*
239 	 * Perform 8 End Of Interrupt Command to make sure AIC
240 	 * will not Lock out nIRQ
241 	 */
242 	for (i = 0; i < 8; i++)
243 		irq_reg_writel(gc, 0, AT91_AIC5_EOICR);
244 
245 	/*
246 	 * Spurious Interrupt ID in Spurious Vector Register.
247 	 * When there is no current interrupt, the IRQ Vector Register
248 	 * reads the value stored in AIC_SPU
249 	 */
250 	irq_reg_writel(gc, 0xffffffff, AT91_AIC5_SPU);
251 
252 	/* No debugging in AIC: Debug (Protect) Control Register */
253 	irq_reg_writel(gc, 0, AT91_AIC5_DCR);
254 
255 	/* Disable and clear all interrupts initially */
256 	for (i = 0; i < domain->revmap_size; i++) {
257 		irq_reg_writel(gc, i, AT91_AIC5_SSR);
258 		irq_reg_writel(gc, i, AT91_AIC5_SVR);
259 		irq_reg_writel(gc, 1, AT91_AIC5_IDCR);
260 		irq_reg_writel(gc, 1, AT91_AIC5_ICCR);
261 	}
262 }
263 
264 static int aic5_irq_domain_xlate(struct irq_domain *d,
265 				 struct device_node *ctrlr,
266 				 const u32 *intspec, unsigned int intsize,
267 				 irq_hw_number_t *out_hwirq,
268 				 unsigned int *out_type)
269 {
270 	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(d, 0);
271 	unsigned smr;
272 	int ret;
273 
274 	if (!bgc)
275 		return -EINVAL;
276 
277 	ret = aic_common_irq_domain_xlate(d, ctrlr, intspec, intsize,
278 					  out_hwirq, out_type);
279 	if (ret)
280 		return ret;
281 
282 	guard(raw_spinlock_irq)(&bgc->lock);
283 	irq_reg_writel(bgc, *out_hwirq, AT91_AIC5_SSR);
284 	smr = irq_reg_readl(bgc, AT91_AIC5_SMR);
285 	aic_common_set_priority(intspec[2], &smr);
286 	irq_reg_writel(bgc, smr, AT91_AIC5_SMR);
287 	return ret;
288 }
289 
290 static const struct irq_domain_ops aic5_irq_ops = {
291 	.map	= irq_map_generic_chip,
292 	.xlate	= aic5_irq_domain_xlate,
293 };
294 
295 static void __init sama5d3_aic_irq_fixup(void)
296 {
297 	aic_common_rtc_irq_fixup();
298 }
299 
300 static void __init sam9x60_aic_irq_fixup(void)
301 {
302 	aic_common_rtc_irq_fixup();
303 	aic_common_rtt_irq_fixup();
304 }
305 
306 static const struct of_device_id aic5_irq_fixups[] __initconst = {
307 	{ .compatible = "atmel,sama5d3", .data = sama5d3_aic_irq_fixup },
308 	{ .compatible = "atmel,sama5d4", .data = sama5d3_aic_irq_fixup },
309 	{ .compatible = "microchip,sam9x60", .data = sam9x60_aic_irq_fixup },
310 	{ .compatible = "microchip,sam9x7", .data = sam9x60_aic_irq_fixup },
311 	{ /* sentinel */ },
312 };
313 
314 static int __init aic5_of_init(struct device_node *node,
315 			       struct device_node *parent,
316 			       int nirqs)
317 {
318 	struct irq_chip_generic *gc;
319 	struct irq_domain *domain;
320 	int nchips;
321 	int i;
322 
323 	if (nirqs > NR_AIC5_IRQS)
324 		return -EINVAL;
325 
326 	if (aic5_domain)
327 		return -EEXIST;
328 
329 	domain = aic_common_of_init(node, &aic5_irq_ops, "atmel-aic5",
330 				    nirqs, aic5_irq_fixups);
331 	if (IS_ERR(domain))
332 		return PTR_ERR(domain);
333 
334 	aic5_domain = domain;
335 	nchips = aic5_domain->revmap_size / 32;
336 	for (i = 0; i < nchips; i++) {
337 		gc = irq_get_domain_generic_chip(domain, i * 32);
338 
339 		gc->chip_types[0].regs.eoi = AT91_AIC5_EOICR;
340 		gc->chip_types[0].chip.irq_mask = aic5_mask;
341 		gc->chip_types[0].chip.irq_unmask = aic5_unmask;
342 		gc->chip_types[0].chip.irq_retrigger = aic5_retrigger;
343 		gc->chip_types[0].chip.irq_set_type = aic5_set_type;
344 		gc->chip_types[0].chip.irq_suspend = aic5_suspend;
345 		gc->chip_types[0].chip.irq_resume = aic5_resume;
346 		gc->chip_types[0].chip.irq_pm_shutdown = aic5_pm_shutdown;
347 	}
348 
349 	aic5_hw_init(domain);
350 	set_handle_irq(aic5_handle);
351 
352 	return 0;
353 }
354 
355 #define NR_SAMA5D2_IRQS		77
356 
357 static int __init sama5d2_aic5_of_init(struct device_node *node,
358 				       struct device_node *parent)
359 {
360 #ifdef CONFIG_PM
361 	smr_cache = kcalloc(DIV_ROUND_UP(NR_SAMA5D2_IRQS, 32) * 32,
362 			    sizeof(*smr_cache), GFP_KERNEL);
363 	if (!smr_cache)
364 		return -ENOMEM;
365 #endif
366 
367 	return aic5_of_init(node, parent, NR_SAMA5D2_IRQS);
368 }
369 IRQCHIP_DECLARE(sama5d2_aic5, "atmel,sama5d2-aic", sama5d2_aic5_of_init);
370 
371 #define NR_SAMA5D3_IRQS		48
372 
373 static int __init sama5d3_aic5_of_init(struct device_node *node,
374 				       struct device_node *parent)
375 {
376 	return aic5_of_init(node, parent, NR_SAMA5D3_IRQS);
377 }
378 IRQCHIP_DECLARE(sama5d3_aic5, "atmel,sama5d3-aic", sama5d3_aic5_of_init);
379 
380 #define NR_SAMA5D4_IRQS		68
381 
382 static int __init sama5d4_aic5_of_init(struct device_node *node,
383 				       struct device_node *parent)
384 {
385 	return aic5_of_init(node, parent, NR_SAMA5D4_IRQS);
386 }
387 IRQCHIP_DECLARE(sama5d4_aic5, "atmel,sama5d4-aic", sama5d4_aic5_of_init);
388 
389 #define NR_SAM9X60_IRQS		50
390 
391 static int __init sam9x60_aic5_of_init(struct device_node *node,
392 				       struct device_node *parent)
393 {
394 	return aic5_of_init(node, parent, NR_SAM9X60_IRQS);
395 }
396 IRQCHIP_DECLARE(sam9x60_aic5, "microchip,sam9x60-aic", sam9x60_aic5_of_init);
397 
398 #define NR_SAM9X7_IRQS		70
399 
400 static int __init sam9x7_aic5_of_init(struct device_node *node, struct device_node *parent)
401 {
402 	return aic5_of_init(node, parent, NR_SAM9X7_IRQS);
403 }
404 IRQCHIP_DECLARE(sam9x7_aic5, "microchip,sam9x7-aic", sam9x7_aic5_of_init);
405