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 asmlinkage void __exception_irq_entry
aic_handle(struct pt_regs * regs)61 aic_handle(struct pt_regs *regs)
62 {
63 struct irq_domain_chip_generic *dgc = aic_domain->gc;
64 struct irq_chip_generic *gc = dgc->gc[0];
65 u32 irqnr;
66 u32 irqstat;
67
68 irqnr = irq_reg_readl(gc, AT91_AIC_IVR);
69 irqstat = irq_reg_readl(gc, AT91_AIC_ISR);
70
71 if (!irqstat)
72 irq_reg_writel(gc, 0, AT91_AIC_EOICR);
73 else
74 handle_domain_irq(aic_domain, irqnr, regs);
75 }
76
aic_retrigger(struct irq_data * d)77 static int aic_retrigger(struct irq_data *d)
78 {
79 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
80
81 /* Enable interrupt on AIC5 */
82 irq_gc_lock(gc);
83 irq_reg_writel(gc, d->mask, AT91_AIC_ISCR);
84 irq_gc_unlock(gc);
85
86 return 1;
87 }
88
aic_set_type(struct irq_data * d,unsigned type)89 static int aic_set_type(struct irq_data *d, unsigned type)
90 {
91 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
92 unsigned int smr;
93 int ret;
94
95 smr = irq_reg_readl(gc, AT91_AIC_SMR(d->hwirq));
96 ret = aic_common_set_type(d, type, &smr);
97 if (ret)
98 return ret;
99
100 irq_reg_writel(gc, smr, AT91_AIC_SMR(d->hwirq));
101
102 return 0;
103 }
104
105 #ifdef CONFIG_PM
aic_suspend(struct irq_data * d)106 static void aic_suspend(struct irq_data *d)
107 {
108 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
109
110 irq_gc_lock(gc);
111 irq_reg_writel(gc, gc->mask_cache, AT91_AIC_IDCR);
112 irq_reg_writel(gc, gc->wake_active, AT91_AIC_IECR);
113 irq_gc_unlock(gc);
114 }
115
aic_resume(struct irq_data * d)116 static void aic_resume(struct irq_data *d)
117 {
118 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
119
120 irq_gc_lock(gc);
121 irq_reg_writel(gc, gc->wake_active, AT91_AIC_IDCR);
122 irq_reg_writel(gc, gc->mask_cache, AT91_AIC_IECR);
123 irq_gc_unlock(gc);
124 }
125
aic_pm_shutdown(struct irq_data * d)126 static void aic_pm_shutdown(struct irq_data *d)
127 {
128 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
129
130 irq_gc_lock(gc);
131 irq_reg_writel(gc, 0xffffffff, AT91_AIC_IDCR);
132 irq_reg_writel(gc, 0xffffffff, AT91_AIC_ICCR);
133 irq_gc_unlock(gc);
134 }
135 #else
136 #define aic_suspend NULL
137 #define aic_resume NULL
138 #define aic_pm_shutdown NULL
139 #endif /* CONFIG_PM */
140
aic_hw_init(struct irq_domain * domain)141 static void __init aic_hw_init(struct irq_domain *domain)
142 {
143 struct irq_chip_generic *gc = irq_get_domain_generic_chip(domain, 0);
144 int i;
145
146 /*
147 * Perform 8 End Of Interrupt Command to make sure AIC
148 * will not Lock out nIRQ
149 */
150 for (i = 0; i < 8; i++)
151 irq_reg_writel(gc, 0, AT91_AIC_EOICR);
152
153 /*
154 * Spurious Interrupt ID in Spurious Vector Register.
155 * When there is no current interrupt, the IRQ Vector Register
156 * reads the value stored in AIC_SPU
157 */
158 irq_reg_writel(gc, 0xffffffff, AT91_AIC_SPU);
159
160 /* No debugging in AIC: Debug (Protect) Control Register */
161 irq_reg_writel(gc, 0, AT91_AIC_DCR);
162
163 /* Disable and clear all interrupts initially */
164 irq_reg_writel(gc, 0xffffffff, AT91_AIC_IDCR);
165 irq_reg_writel(gc, 0xffffffff, AT91_AIC_ICCR);
166
167 for (i = 0; i < 32; i++)
168 irq_reg_writel(gc, i, AT91_AIC_SVR(i));
169 }
170
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)171 static int aic_irq_domain_xlate(struct irq_domain *d,
172 struct device_node *ctrlr,
173 const u32 *intspec, unsigned int intsize,
174 irq_hw_number_t *out_hwirq,
175 unsigned int *out_type)
176 {
177 struct irq_domain_chip_generic *dgc = d->gc;
178 struct irq_chip_generic *gc;
179 unsigned long flags;
180 unsigned smr;
181 int idx;
182 int ret;
183
184 if (!dgc)
185 return -EINVAL;
186
187 ret = aic_common_irq_domain_xlate(d, ctrlr, intspec, intsize,
188 out_hwirq, out_type);
189 if (ret)
190 return ret;
191
192 idx = intspec[0] / dgc->irqs_per_chip;
193 if (idx >= dgc->num_chips)
194 return -EINVAL;
195
196 gc = dgc->gc[idx];
197
198 irq_gc_lock_irqsave(gc, flags);
199 smr = irq_reg_readl(gc, AT91_AIC_SMR(*out_hwirq));
200 aic_common_set_priority(intspec[2], &smr);
201 irq_reg_writel(gc, smr, AT91_AIC_SMR(*out_hwirq));
202 irq_gc_unlock_irqrestore(gc, flags);
203
204 return ret;
205 }
206
207 static const struct irq_domain_ops aic_irq_ops = {
208 .map = irq_map_generic_chip,
209 .xlate = aic_irq_domain_xlate,
210 };
211
at91rm9200_aic_irq_fixup(void)212 static void __init at91rm9200_aic_irq_fixup(void)
213 {
214 aic_common_rtc_irq_fixup();
215 }
216
at91sam9260_aic_irq_fixup(void)217 static void __init at91sam9260_aic_irq_fixup(void)
218 {
219 aic_common_rtt_irq_fixup();
220 }
221
at91sam9g45_aic_irq_fixup(void)222 static void __init at91sam9g45_aic_irq_fixup(void)
223 {
224 aic_common_rtc_irq_fixup();
225 aic_common_rtt_irq_fixup();
226 }
227
228 static const struct of_device_id aic_irq_fixups[] __initconst = {
229 { .compatible = "atmel,at91rm9200", .data = at91rm9200_aic_irq_fixup },
230 { .compatible = "atmel,at91sam9g45", .data = at91sam9g45_aic_irq_fixup },
231 { .compatible = "atmel,at91sam9n12", .data = at91rm9200_aic_irq_fixup },
232 { .compatible = "atmel,at91sam9rl", .data = at91sam9g45_aic_irq_fixup },
233 { .compatible = "atmel,at91sam9x5", .data = at91rm9200_aic_irq_fixup },
234 { .compatible = "atmel,at91sam9260", .data = at91sam9260_aic_irq_fixup },
235 { .compatible = "atmel,at91sam9261", .data = at91sam9260_aic_irq_fixup },
236 { .compatible = "atmel,at91sam9263", .data = at91sam9260_aic_irq_fixup },
237 { .compatible = "atmel,at91sam9g20", .data = at91sam9260_aic_irq_fixup },
238 { /* sentinel */ },
239 };
240
aic_of_init(struct device_node * node,struct device_node * parent)241 static int __init aic_of_init(struct device_node *node,
242 struct device_node *parent)
243 {
244 struct irq_chip_generic *gc;
245 struct irq_domain *domain;
246
247 if (aic_domain)
248 return -EEXIST;
249
250 domain = aic_common_of_init(node, &aic_irq_ops, "atmel-aic",
251 NR_AIC_IRQS, aic_irq_fixups);
252 if (IS_ERR(domain))
253 return PTR_ERR(domain);
254
255 aic_domain = domain;
256 gc = irq_get_domain_generic_chip(domain, 0);
257
258 gc->chip_types[0].regs.eoi = AT91_AIC_EOICR;
259 gc->chip_types[0].regs.enable = AT91_AIC_IECR;
260 gc->chip_types[0].regs.disable = AT91_AIC_IDCR;
261 gc->chip_types[0].chip.irq_mask = irq_gc_mask_disable_reg;
262 gc->chip_types[0].chip.irq_unmask = irq_gc_unmask_enable_reg;
263 gc->chip_types[0].chip.irq_retrigger = aic_retrigger;
264 gc->chip_types[0].chip.irq_set_type = aic_set_type;
265 gc->chip_types[0].chip.irq_suspend = aic_suspend;
266 gc->chip_types[0].chip.irq_resume = aic_resume;
267 gc->chip_types[0].chip.irq_pm_shutdown = aic_pm_shutdown;
268
269 aic_hw_init(domain);
270 set_handle_irq(aic_handle);
271
272 return 0;
273 }
274 IRQCHIP_DECLARE(at91rm9200_aic, "atmel,at91rm9200-aic", aic_of_init);
275