xref: /linux/drivers/irqchip/irq-atmel-aic.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 /*
2  * Atmel AT91 AIC (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_AIC_IRQS	32
38 
39 #define AT91_AIC_SMR(n)			((n) * 4)
40 
41 #define AT91_AIC_SVR(n)			(0x80 + ((n) * 4))
42 #define AT91_AIC_IVR			0x100
43 #define AT91_AIC_FVR			0x104
44 #define AT91_AIC_ISR			0x108
45 
46 #define AT91_AIC_IPR			0x10c
47 #define AT91_AIC_IMR			0x110
48 #define AT91_AIC_CISR			0x114
49 
50 #define AT91_AIC_IECR			0x120
51 #define AT91_AIC_IDCR			0x124
52 #define AT91_AIC_ICCR			0x128
53 #define AT91_AIC_ISCR			0x12c
54 #define AT91_AIC_EOICR			0x130
55 #define AT91_AIC_SPU			0x134
56 #define AT91_AIC_DCR			0x138
57 
58 static struct irq_domain *aic_domain;
59 
60 static void __exception_irq_entry aic_handle(struct pt_regs *regs)
61 {
62 	struct irq_domain_chip_generic *dgc = aic_domain->gc;
63 	struct irq_chip_generic *gc = dgc->gc[0];
64 	u32 irqnr;
65 	u32 irqstat;
66 
67 	irqnr = irq_reg_readl(gc, AT91_AIC_IVR);
68 	irqstat = irq_reg_readl(gc, AT91_AIC_ISR);
69 
70 	if (!irqstat)
71 		irq_reg_writel(gc, 0, AT91_AIC_EOICR);
72 	else
73 		generic_handle_domain_irq(aic_domain, irqnr);
74 }
75 
76 static int aic_retrigger(struct irq_data *d)
77 {
78 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
79 
80 	/* Enable interrupt on AIC5 */
81 	irq_gc_lock(gc);
82 	irq_reg_writel(gc, d->mask, AT91_AIC_ISCR);
83 	irq_gc_unlock(gc);
84 
85 	return 1;
86 }
87 
88 static int aic_set_type(struct irq_data *d, unsigned type)
89 {
90 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
91 	unsigned int smr;
92 	int ret;
93 
94 	smr = irq_reg_readl(gc, AT91_AIC_SMR(d->hwirq));
95 	ret = aic_common_set_type(d, type, &smr);
96 	if (ret)
97 		return ret;
98 
99 	irq_reg_writel(gc, smr, AT91_AIC_SMR(d->hwirq));
100 
101 	return 0;
102 }
103 
104 #ifdef CONFIG_PM
105 static void aic_suspend(struct irq_data *d)
106 {
107 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
108 
109 	irq_gc_lock(gc);
110 	irq_reg_writel(gc, gc->mask_cache, AT91_AIC_IDCR);
111 	irq_reg_writel(gc, gc->wake_active, AT91_AIC_IECR);
112 	irq_gc_unlock(gc);
113 }
114 
115 static void aic_resume(struct irq_data *d)
116 {
117 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
118 
119 	irq_gc_lock(gc);
120 	irq_reg_writel(gc, gc->wake_active, AT91_AIC_IDCR);
121 	irq_reg_writel(gc, gc->mask_cache, AT91_AIC_IECR);
122 	irq_gc_unlock(gc);
123 }
124 
125 static void aic_pm_shutdown(struct irq_data *d)
126 {
127 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
128 
129 	irq_gc_lock(gc);
130 	irq_reg_writel(gc, 0xffffffff, AT91_AIC_IDCR);
131 	irq_reg_writel(gc, 0xffffffff, AT91_AIC_ICCR);
132 	irq_gc_unlock(gc);
133 }
134 #else
135 #define aic_suspend		NULL
136 #define aic_resume		NULL
137 #define aic_pm_shutdown		NULL
138 #endif /* CONFIG_PM */
139 
140 static void __init aic_hw_init(struct irq_domain *domain)
141 {
142 	struct irq_chip_generic *gc = irq_get_domain_generic_chip(domain, 0);
143 	int i;
144 
145 	/*
146 	 * Perform 8 End Of Interrupt Command to make sure AIC
147 	 * will not Lock out nIRQ
148 	 */
149 	for (i = 0; i < 8; i++)
150 		irq_reg_writel(gc, 0, AT91_AIC_EOICR);
151 
152 	/*
153 	 * Spurious Interrupt ID in Spurious Vector Register.
154 	 * When there is no current interrupt, the IRQ Vector Register
155 	 * reads the value stored in AIC_SPU
156 	 */
157 	irq_reg_writel(gc, 0xffffffff, AT91_AIC_SPU);
158 
159 	/* No debugging in AIC: Debug (Protect) Control Register */
160 	irq_reg_writel(gc, 0, AT91_AIC_DCR);
161 
162 	/* Disable and clear all interrupts initially */
163 	irq_reg_writel(gc, 0xffffffff, AT91_AIC_IDCR);
164 	irq_reg_writel(gc, 0xffffffff, AT91_AIC_ICCR);
165 
166 	for (i = 0; i < 32; i++)
167 		irq_reg_writel(gc, i, AT91_AIC_SVR(i));
168 }
169 
170 static int aic_irq_domain_xlate(struct irq_domain *d,
171 				struct device_node *ctrlr,
172 				const u32 *intspec, unsigned int intsize,
173 				irq_hw_number_t *out_hwirq,
174 				unsigned int *out_type)
175 {
176 	struct irq_domain_chip_generic *dgc = d->gc;
177 	struct irq_chip_generic *gc;
178 	unsigned long flags;
179 	unsigned smr;
180 	int idx;
181 	int ret;
182 
183 	if (!dgc)
184 		return -EINVAL;
185 
186 	ret = aic_common_irq_domain_xlate(d, ctrlr, intspec, intsize,
187 					  out_hwirq, out_type);
188 	if (ret)
189 		return ret;
190 
191 	idx = intspec[0] / dgc->irqs_per_chip;
192 	if (idx >= dgc->num_chips)
193 		return -EINVAL;
194 
195 	gc = dgc->gc[idx];
196 
197 	irq_gc_lock_irqsave(gc, flags);
198 	smr = irq_reg_readl(gc, AT91_AIC_SMR(*out_hwirq));
199 	aic_common_set_priority(intspec[2], &smr);
200 	irq_reg_writel(gc, smr, AT91_AIC_SMR(*out_hwirq));
201 	irq_gc_unlock_irqrestore(gc, flags);
202 
203 	return ret;
204 }
205 
206 static const struct irq_domain_ops aic_irq_ops = {
207 	.map	= irq_map_generic_chip,
208 	.xlate	= aic_irq_domain_xlate,
209 };
210 
211 static void __init at91rm9200_aic_irq_fixup(void)
212 {
213 	aic_common_rtc_irq_fixup();
214 }
215 
216 static void __init at91sam9260_aic_irq_fixup(void)
217 {
218 	aic_common_rtt_irq_fixup();
219 }
220 
221 static void __init at91sam9g45_aic_irq_fixup(void)
222 {
223 	aic_common_rtc_irq_fixup();
224 	aic_common_rtt_irq_fixup();
225 }
226 
227 static const struct of_device_id aic_irq_fixups[] __initconst = {
228 	{ .compatible = "atmel,at91rm9200", .data = at91rm9200_aic_irq_fixup },
229 	{ .compatible = "atmel,at91sam9g45", .data = at91sam9g45_aic_irq_fixup },
230 	{ .compatible = "atmel,at91sam9n12", .data = at91rm9200_aic_irq_fixup },
231 	{ .compatible = "atmel,at91sam9rl", .data = at91sam9g45_aic_irq_fixup },
232 	{ .compatible = "atmel,at91sam9x5", .data = at91rm9200_aic_irq_fixup },
233 	{ .compatible = "atmel,at91sam9260", .data = at91sam9260_aic_irq_fixup },
234 	{ .compatible = "atmel,at91sam9261", .data = at91sam9260_aic_irq_fixup },
235 	{ .compatible = "atmel,at91sam9263", .data = at91sam9260_aic_irq_fixup },
236 	{ .compatible = "atmel,at91sam9g20", .data = at91sam9260_aic_irq_fixup },
237 	{ /* sentinel */ },
238 };
239 
240 static int __init aic_of_init(struct device_node *node,
241 			      struct device_node *parent)
242 {
243 	struct irq_chip_generic *gc;
244 	struct irq_domain *domain;
245 
246 	if (aic_domain)
247 		return -EEXIST;
248 
249 	domain = aic_common_of_init(node, &aic_irq_ops, "atmel-aic",
250 				    NR_AIC_IRQS, aic_irq_fixups);
251 	if (IS_ERR(domain))
252 		return PTR_ERR(domain);
253 
254 	aic_domain = domain;
255 	gc = irq_get_domain_generic_chip(domain, 0);
256 
257 	gc->chip_types[0].regs.eoi = AT91_AIC_EOICR;
258 	gc->chip_types[0].regs.enable = AT91_AIC_IECR;
259 	gc->chip_types[0].regs.disable = AT91_AIC_IDCR;
260 	gc->chip_types[0].chip.irq_mask = irq_gc_mask_disable_reg;
261 	gc->chip_types[0].chip.irq_unmask = irq_gc_unmask_enable_reg;
262 	gc->chip_types[0].chip.irq_retrigger = aic_retrigger;
263 	gc->chip_types[0].chip.irq_set_type = aic_set_type;
264 	gc->chip_types[0].chip.irq_suspend = aic_suspend;
265 	gc->chip_types[0].chip.irq_resume = aic_resume;
266 	gc->chip_types[0].chip.irq_pm_shutdown = aic_pm_shutdown;
267 
268 	aic_hw_init(domain);
269 	set_handle_irq(aic_handle);
270 
271 	return 0;
272 }
273 IRQCHIP_DECLARE(at91rm9200_aic, "atmel,at91rm9200-aic", aic_of_init);
274