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
aic_handle(struct pt_regs * regs)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
aic_retrigger(struct irq_data * d)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
aic_set_type(struct irq_data * d,unsigned type)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
aic_suspend(struct irq_data * d)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
aic_resume(struct irq_data * d)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
aic_pm_shutdown(struct irq_data * d)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
aic_hw_init(struct irq_domain * domain)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
aic_irq_domain_xlate(struct irq_domain * d,struct device_node * ctrlr,const u32 * intspec,unsigned int intsize,irq_hw_number_t * out_hwirq,unsigned int * out_type)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
at91rm9200_aic_irq_fixup(void)211 static void __init at91rm9200_aic_irq_fixup(void)
212 {
213 aic_common_rtc_irq_fixup();
214 }
215
at91sam9260_aic_irq_fixup(void)216 static void __init at91sam9260_aic_irq_fixup(void)
217 {
218 aic_common_rtt_irq_fixup();
219 }
220
at91sam9g45_aic_irq_fixup(void)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
aic_of_init(struct device_node * node,struct device_node * parent)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