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
68static struct irq_domain *aic5_domain;
69
70static asmlinkage void __exception_irq_entry
71aic5_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		generic_handle_domain_irq(aic5_domain, irqnr);
84}
85
86static 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
103static 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
120static 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 1;
132}
133
134static 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
153static u32 *smr_cache;
154
155static void aic5_suspend(struct irq_data *d)
156{
157	struct irq_domain *domain = d->domain;
158	struct irq_domain_chip_generic *dgc = domain->gc;
159	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
160	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
161	int i;
162	u32 mask;
163
164	if (smr_cache)
165		for (i = 0; i < domain->revmap_size; i++) {
166			irq_reg_writel(bgc, i, AT91_AIC5_SSR);
167			smr_cache[i] = irq_reg_readl(bgc, AT91_AIC5_SMR);
168		}
169
170	irq_gc_lock(bgc);
171	for (i = 0; i < dgc->irqs_per_chip; i++) {
172		mask = 1 << i;
173		if ((mask & gc->mask_cache) == (mask & gc->wake_active))
174			continue;
175
176		irq_reg_writel(bgc, i + gc->irq_base, AT91_AIC5_SSR);
177		if (mask & gc->wake_active)
178			irq_reg_writel(bgc, 1, AT91_AIC5_IECR);
179		else
180			irq_reg_writel(bgc, 1, AT91_AIC5_IDCR);
181	}
182	irq_gc_unlock(bgc);
183}
184
185static void aic5_resume(struct irq_data *d)
186{
187	struct irq_domain *domain = d->domain;
188	struct irq_domain_chip_generic *dgc = domain->gc;
189	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
190	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
191	int i;
192	u32 mask;
193
194	irq_gc_lock(bgc);
195
196	if (smr_cache) {
197		irq_reg_writel(bgc, 0xffffffff, AT91_AIC5_SPU);
198		for (i = 0; i < domain->revmap_size; i++) {
199			irq_reg_writel(bgc, i, AT91_AIC5_SSR);
200			irq_reg_writel(bgc, i, AT91_AIC5_SVR);
201			irq_reg_writel(bgc, smr_cache[i], AT91_AIC5_SMR);
202		}
203	}
204
205	for (i = 0; i < dgc->irqs_per_chip; i++) {
206		mask = 1 << i;
207
208		if (!smr_cache &&
209		    ((mask & gc->mask_cache) == (mask & gc->wake_active)))
210			continue;
211
212		irq_reg_writel(bgc, i + gc->irq_base, AT91_AIC5_SSR);
213		if (mask & gc->mask_cache)
214			irq_reg_writel(bgc, 1, AT91_AIC5_IECR);
215		else
216			irq_reg_writel(bgc, 1, AT91_AIC5_IDCR);
217	}
218	irq_gc_unlock(bgc);
219}
220
221static void aic5_pm_shutdown(struct irq_data *d)
222{
223	struct irq_domain *domain = d->domain;
224	struct irq_domain_chip_generic *dgc = domain->gc;
225	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(domain, 0);
226	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
227	int i;
228
229	irq_gc_lock(bgc);
230	for (i = 0; i < dgc->irqs_per_chip; i++) {
231		irq_reg_writel(bgc, i + gc->irq_base, AT91_AIC5_SSR);
232		irq_reg_writel(bgc, 1, AT91_AIC5_IDCR);
233		irq_reg_writel(bgc, 1, AT91_AIC5_ICCR);
234	}
235	irq_gc_unlock(bgc);
236}
237#else
238#define aic5_suspend		NULL
239#define aic5_resume		NULL
240#define aic5_pm_shutdown	NULL
241#endif /* CONFIG_PM */
242
243static void __init aic5_hw_init(struct irq_domain *domain)
244{
245	struct irq_chip_generic *gc = irq_get_domain_generic_chip(domain, 0);
246	int i;
247
248	/*
249	 * Perform 8 End Of Interrupt Command to make sure AIC
250	 * will not Lock out nIRQ
251	 */
252	for (i = 0; i < 8; i++)
253		irq_reg_writel(gc, 0, AT91_AIC5_EOICR);
254
255	/*
256	 * Spurious Interrupt ID in Spurious Vector Register.
257	 * When there is no current interrupt, the IRQ Vector Register
258	 * reads the value stored in AIC_SPU
259	 */
260	irq_reg_writel(gc, 0xffffffff, AT91_AIC5_SPU);
261
262	/* No debugging in AIC: Debug (Protect) Control Register */
263	irq_reg_writel(gc, 0, AT91_AIC5_DCR);
264
265	/* Disable and clear all interrupts initially */
266	for (i = 0; i < domain->revmap_size; i++) {
267		irq_reg_writel(gc, i, AT91_AIC5_SSR);
268		irq_reg_writel(gc, i, AT91_AIC5_SVR);
269		irq_reg_writel(gc, 1, AT91_AIC5_IDCR);
270		irq_reg_writel(gc, 1, AT91_AIC5_ICCR);
271	}
272}
273
274static int aic5_irq_domain_xlate(struct irq_domain *d,
275				 struct device_node *ctrlr,
276				 const u32 *intspec, unsigned int intsize,
277				 irq_hw_number_t *out_hwirq,
278				 unsigned int *out_type)
279{
280	struct irq_chip_generic *bgc = irq_get_domain_generic_chip(d, 0);
281	unsigned long flags;
282	unsigned smr;
283	int ret;
284
285	if (!bgc)
286		return -EINVAL;
287
288	ret = aic_common_irq_domain_xlate(d, ctrlr, intspec, intsize,
289					  out_hwirq, out_type);
290	if (ret)
291		return ret;
292
293	irq_gc_lock_irqsave(bgc, flags);
294	irq_reg_writel(bgc, *out_hwirq, AT91_AIC5_SSR);
295	smr = irq_reg_readl(bgc, AT91_AIC5_SMR);
296	aic_common_set_priority(intspec[2], &smr);
297	irq_reg_writel(bgc, smr, AT91_AIC5_SMR);
298	irq_gc_unlock_irqrestore(bgc, flags);
299
300	return ret;
301}
302
303static const struct irq_domain_ops aic5_irq_ops = {
304	.map	= irq_map_generic_chip,
305	.xlate	= aic5_irq_domain_xlate,
306};
307
308static void __init sama5d3_aic_irq_fixup(void)
309{
310	aic_common_rtc_irq_fixup();
311}
312
313static void __init sam9x60_aic_irq_fixup(void)
314{
315	aic_common_rtc_irq_fixup();
316	aic_common_rtt_irq_fixup();
317}
318
319static const struct of_device_id aic5_irq_fixups[] __initconst = {
320	{ .compatible = "atmel,sama5d3", .data = sama5d3_aic_irq_fixup },
321	{ .compatible = "atmel,sama5d4", .data = sama5d3_aic_irq_fixup },
322	{ .compatible = "microchip,sam9x60", .data = sam9x60_aic_irq_fixup },
323	{ /* sentinel */ },
324};
325
326static int __init aic5_of_init(struct device_node *node,
327			       struct device_node *parent,
328			       int nirqs)
329{
330	struct irq_chip_generic *gc;
331	struct irq_domain *domain;
332	int nchips;
333	int i;
334
335	if (nirqs > NR_AIC5_IRQS)
336		return -EINVAL;
337
338	if (aic5_domain)
339		return -EEXIST;
340
341	domain = aic_common_of_init(node, &aic5_irq_ops, "atmel-aic5",
342				    nirqs, aic5_irq_fixups);
343	if (IS_ERR(domain))
344		return PTR_ERR(domain);
345
346	aic5_domain = domain;
347	nchips = aic5_domain->revmap_size / 32;
348	for (i = 0; i < nchips; i++) {
349		gc = irq_get_domain_generic_chip(domain, i * 32);
350
351		gc->chip_types[0].regs.eoi = AT91_AIC5_EOICR;
352		gc->chip_types[0].chip.irq_mask = aic5_mask;
353		gc->chip_types[0].chip.irq_unmask = aic5_unmask;
354		gc->chip_types[0].chip.irq_retrigger = aic5_retrigger;
355		gc->chip_types[0].chip.irq_set_type = aic5_set_type;
356		gc->chip_types[0].chip.irq_suspend = aic5_suspend;
357		gc->chip_types[0].chip.irq_resume = aic5_resume;
358		gc->chip_types[0].chip.irq_pm_shutdown = aic5_pm_shutdown;
359	}
360
361	aic5_hw_init(domain);
362	set_handle_irq(aic5_handle);
363
364	return 0;
365}
366
367#define NR_SAMA5D2_IRQS		77
368
369static int __init sama5d2_aic5_of_init(struct device_node *node,
370				       struct device_node *parent)
371{
372#ifdef CONFIG_PM
373	smr_cache = kcalloc(DIV_ROUND_UP(NR_SAMA5D2_IRQS, 32) * 32,
374			    sizeof(*smr_cache), GFP_KERNEL);
375	if (!smr_cache)
376		return -ENOMEM;
377#endif
378
379	return aic5_of_init(node, parent, NR_SAMA5D2_IRQS);
380}
381IRQCHIP_DECLARE(sama5d2_aic5, "atmel,sama5d2-aic", sama5d2_aic5_of_init);
382
383#define NR_SAMA5D3_IRQS		48
384
385static int __init sama5d3_aic5_of_init(struct device_node *node,
386				       struct device_node *parent)
387{
388	return aic5_of_init(node, parent, NR_SAMA5D3_IRQS);
389}
390IRQCHIP_DECLARE(sama5d3_aic5, "atmel,sama5d3-aic", sama5d3_aic5_of_init);
391
392#define NR_SAMA5D4_IRQS		68
393
394static int __init sama5d4_aic5_of_init(struct device_node *node,
395				       struct device_node *parent)
396{
397	return aic5_of_init(node, parent, NR_SAMA5D4_IRQS);
398}
399IRQCHIP_DECLARE(sama5d4_aic5, "atmel,sama5d4-aic", sama5d4_aic5_of_init);
400
401#define NR_SAM9X60_IRQS		50
402
403static int __init sam9x60_aic5_of_init(struct device_node *node,
404				       struct device_node *parent)
405{
406	return aic5_of_init(node, parent, NR_SAM9X60_IRQS);
407}
408IRQCHIP_DECLARE(sam9x60_aic5, "microchip,sam9x60-aic", sam9x60_aic5_of_init);
409