xref: /linux/drivers/irqchip/irq-omap-intc.c (revision 827634added7f38b7d724cab1dccdb2b004c13c3)
1 /*
2  * linux/arch/arm/mach-omap2/irq.c
3  *
4  * Interrupt handler for OMAP2 boards.
5  *
6  * Copyright (C) 2005 Nokia Corporation
7  * Author: Paul Mundt <paul.mundt@nokia.com>
8  *
9  * This file is subject to the terms and conditions of the GNU General Public
10  * License. See the file "COPYING" in the main directory of this archive
11  * for more details.
12  */
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/interrupt.h>
17 #include <linux/io.h>
18 
19 #include <asm/exception.h>
20 #include <linux/irqdomain.h>
21 #include <linux/of.h>
22 #include <linux/of_address.h>
23 #include <linux/of_irq.h>
24 
25 #include "irqchip.h"
26 
27 /* Define these here for now until we drop all board-files */
28 #define OMAP24XX_IC_BASE	0x480fe000
29 #define OMAP34XX_IC_BASE	0x48200000
30 
31 /* selected INTC register offsets */
32 
33 #define INTC_REVISION		0x0000
34 #define INTC_SYSCONFIG		0x0010
35 #define INTC_SYSSTATUS		0x0014
36 #define INTC_SIR		0x0040
37 #define INTC_CONTROL		0x0048
38 #define INTC_PROTECTION		0x004C
39 #define INTC_IDLE		0x0050
40 #define INTC_THRESHOLD		0x0068
41 #define INTC_MIR0		0x0084
42 #define INTC_MIR_CLEAR0		0x0088
43 #define INTC_MIR_SET0		0x008c
44 #define INTC_PENDING_IRQ0	0x0098
45 #define INTC_PENDING_IRQ1	0x00b8
46 #define INTC_PENDING_IRQ2	0x00d8
47 #define INTC_PENDING_IRQ3	0x00f8
48 #define INTC_ILR0		0x0100
49 
50 #define ACTIVEIRQ_MASK		0x7f	/* omap2/3 active interrupt bits */
51 #define INTCPS_NR_ILR_REGS	128
52 #define INTCPS_NR_MIR_REGS	4
53 
54 #define INTC_IDLE_FUNCIDLE	(1 << 0)
55 #define INTC_IDLE_TURBO		(1 << 1)
56 
57 #define INTC_PROTECTION_ENABLE	(1 << 0)
58 
59 struct omap_intc_regs {
60 	u32 sysconfig;
61 	u32 protection;
62 	u32 idle;
63 	u32 threshold;
64 	u32 ilr[INTCPS_NR_ILR_REGS];
65 	u32 mir[INTCPS_NR_MIR_REGS];
66 };
67 static struct omap_intc_regs intc_context;
68 
69 static struct irq_domain *domain;
70 static void __iomem *omap_irq_base;
71 static int omap_nr_pending = 3;
72 static int omap_nr_irqs = 96;
73 
74 static void intc_writel(u32 reg, u32 val)
75 {
76 	writel_relaxed(val, omap_irq_base + reg);
77 }
78 
79 static u32 intc_readl(u32 reg)
80 {
81 	return readl_relaxed(omap_irq_base + reg);
82 }
83 
84 void omap_intc_save_context(void)
85 {
86 	int i;
87 
88 	intc_context.sysconfig =
89 		intc_readl(INTC_SYSCONFIG);
90 	intc_context.protection =
91 		intc_readl(INTC_PROTECTION);
92 	intc_context.idle =
93 		intc_readl(INTC_IDLE);
94 	intc_context.threshold =
95 		intc_readl(INTC_THRESHOLD);
96 
97 	for (i = 0; i < omap_nr_irqs; i++)
98 		intc_context.ilr[i] =
99 			intc_readl((INTC_ILR0 + 0x4 * i));
100 	for (i = 0; i < INTCPS_NR_MIR_REGS; i++)
101 		intc_context.mir[i] =
102 			intc_readl(INTC_MIR0 + (0x20 * i));
103 }
104 
105 void omap_intc_restore_context(void)
106 {
107 	int i;
108 
109 	intc_writel(INTC_SYSCONFIG, intc_context.sysconfig);
110 	intc_writel(INTC_PROTECTION, intc_context.protection);
111 	intc_writel(INTC_IDLE, intc_context.idle);
112 	intc_writel(INTC_THRESHOLD, intc_context.threshold);
113 
114 	for (i = 0; i < omap_nr_irqs; i++)
115 		intc_writel(INTC_ILR0 + 0x4 * i,
116 				intc_context.ilr[i]);
117 
118 	for (i = 0; i < INTCPS_NR_MIR_REGS; i++)
119 		intc_writel(INTC_MIR0 + 0x20 * i,
120 			intc_context.mir[i]);
121 	/* MIRs are saved and restore with other PRCM registers */
122 }
123 
124 void omap3_intc_prepare_idle(void)
125 {
126 	/*
127 	 * Disable autoidle as it can stall interrupt controller,
128 	 * cf. errata ID i540 for 3430 (all revisions up to 3.1.x)
129 	 */
130 	intc_writel(INTC_SYSCONFIG, 0);
131 	intc_writel(INTC_IDLE, INTC_IDLE_TURBO);
132 }
133 
134 void omap3_intc_resume_idle(void)
135 {
136 	/* Re-enable autoidle */
137 	intc_writel(INTC_SYSCONFIG, 1);
138 	intc_writel(INTC_IDLE, 0);
139 }
140 
141 /* XXX: FIQ and additional INTC support (only MPU at the moment) */
142 static void omap_ack_irq(struct irq_data *d)
143 {
144 	intc_writel(INTC_CONTROL, 0x1);
145 }
146 
147 static void omap_mask_ack_irq(struct irq_data *d)
148 {
149 	irq_gc_mask_disable_reg(d);
150 	omap_ack_irq(d);
151 }
152 
153 static void __init omap_irq_soft_reset(void)
154 {
155 	unsigned long tmp;
156 
157 	tmp = intc_readl(INTC_REVISION) & 0xff;
158 
159 	pr_info("IRQ: Found an INTC at 0x%p (revision %ld.%ld) with %d interrupts\n",
160 		omap_irq_base, tmp >> 4, tmp & 0xf, omap_nr_irqs);
161 
162 	tmp = intc_readl(INTC_SYSCONFIG);
163 	tmp |= 1 << 1;	/* soft reset */
164 	intc_writel(INTC_SYSCONFIG, tmp);
165 
166 	while (!(intc_readl(INTC_SYSSTATUS) & 0x1))
167 		/* Wait for reset to complete */;
168 
169 	/* Enable autoidle */
170 	intc_writel(INTC_SYSCONFIG, 1 << 0);
171 }
172 
173 int omap_irq_pending(void)
174 {
175 	int i;
176 
177 	for (i = 0; i < omap_nr_pending; i++)
178 		if (intc_readl(INTC_PENDING_IRQ0 + (0x20 * i)))
179 			return 1;
180 	return 0;
181 }
182 
183 void omap3_intc_suspend(void)
184 {
185 	/* A pending interrupt would prevent OMAP from entering suspend */
186 	omap_ack_irq(NULL);
187 }
188 
189 static int __init omap_alloc_gc_of(struct irq_domain *d, void __iomem *base)
190 {
191 	int ret;
192 	int i;
193 
194 	ret = irq_alloc_domain_generic_chips(d, 32, 1, "INTC",
195 			handle_level_irq, IRQ_NOREQUEST | IRQ_NOPROBE,
196 			IRQ_LEVEL, 0);
197 	if (ret) {
198 		pr_warn("Failed to allocate irq chips\n");
199 		return ret;
200 	}
201 
202 	for (i = 0; i < omap_nr_pending; i++) {
203 		struct irq_chip_generic *gc;
204 		struct irq_chip_type *ct;
205 
206 		gc = irq_get_domain_generic_chip(d, 32 * i);
207 		gc->reg_base = base;
208 		ct = gc->chip_types;
209 
210 		ct->type = IRQ_TYPE_LEVEL_MASK;
211 		ct->handler = handle_level_irq;
212 
213 		ct->chip.irq_ack = omap_mask_ack_irq;
214 		ct->chip.irq_mask = irq_gc_mask_disable_reg;
215 		ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
216 
217 		ct->chip.flags |= IRQCHIP_SKIP_SET_WAKE;
218 
219 		ct->regs.enable = INTC_MIR_CLEAR0 + 32 * i;
220 		ct->regs.disable = INTC_MIR_SET0 + 32 * i;
221 	}
222 
223 	return 0;
224 }
225 
226 static void __init omap_alloc_gc_legacy(void __iomem *base,
227 		unsigned int irq_start, unsigned int num)
228 {
229 	struct irq_chip_generic *gc;
230 	struct irq_chip_type *ct;
231 
232 	gc = irq_alloc_generic_chip("INTC", 1, irq_start, base,
233 			handle_level_irq);
234 	ct = gc->chip_types;
235 	ct->chip.irq_ack = omap_mask_ack_irq;
236 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
237 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
238 	ct->chip.flags |= IRQCHIP_SKIP_SET_WAKE;
239 
240 	ct->regs.enable = INTC_MIR_CLEAR0;
241 	ct->regs.disable = INTC_MIR_SET0;
242 	irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
243 			IRQ_NOREQUEST | IRQ_NOPROBE, 0);
244 }
245 
246 static int __init omap_init_irq_of(struct device_node *node)
247 {
248 	int ret;
249 
250 	omap_irq_base = of_iomap(node, 0);
251 	if (WARN_ON(!omap_irq_base))
252 		return -ENOMEM;
253 
254 	domain = irq_domain_add_linear(node, omap_nr_irqs,
255 			&irq_generic_chip_ops, NULL);
256 
257 	omap_irq_soft_reset();
258 
259 	ret = omap_alloc_gc_of(domain, omap_irq_base);
260 	if (ret < 0)
261 		irq_domain_remove(domain);
262 
263 	return ret;
264 }
265 
266 static int __init omap_init_irq_legacy(u32 base, struct device_node *node)
267 {
268 	int j, irq_base;
269 
270 	omap_irq_base = ioremap(base, SZ_4K);
271 	if (WARN_ON(!omap_irq_base))
272 		return -ENOMEM;
273 
274 	irq_base = irq_alloc_descs(-1, 0, omap_nr_irqs, 0);
275 	if (irq_base < 0) {
276 		pr_warn("Couldn't allocate IRQ numbers\n");
277 		irq_base = 0;
278 	}
279 
280 	domain = irq_domain_add_legacy(node, omap_nr_irqs, irq_base, 0,
281 			&irq_domain_simple_ops, NULL);
282 
283 	omap_irq_soft_reset();
284 
285 	for (j = 0; j < omap_nr_irqs; j += 32)
286 		omap_alloc_gc_legacy(omap_irq_base + j, j + irq_base, 32);
287 
288 	return 0;
289 }
290 
291 static void __init omap_irq_enable_protection(void)
292 {
293 	u32 reg;
294 
295 	reg = intc_readl(INTC_PROTECTION);
296 	reg |= INTC_PROTECTION_ENABLE;
297 	intc_writel(INTC_PROTECTION, reg);
298 }
299 
300 static int __init omap_init_irq(u32 base, struct device_node *node)
301 {
302 	int ret;
303 
304 	/*
305 	 * FIXME legacy OMAP DMA driver sitting under arch/arm/plat-omap/dma.c
306 	 * depends is still not ready for linear IRQ domains; because of that
307 	 * we need to temporarily "blacklist" OMAP2 and OMAP3 devices from using
308 	 * linear IRQ Domain until that driver is finally fixed.
309 	 */
310 	if (of_device_is_compatible(node, "ti,omap2-intc") ||
311 			of_device_is_compatible(node, "ti,omap3-intc")) {
312 		struct resource res;
313 
314 		if (of_address_to_resource(node, 0, &res))
315 			return -ENOMEM;
316 
317 		base = res.start;
318 		ret = omap_init_irq_legacy(base, node);
319 	} else if (node) {
320 		ret = omap_init_irq_of(node);
321 	} else {
322 		ret = omap_init_irq_legacy(base, NULL);
323 	}
324 
325 	if (ret == 0)
326 		omap_irq_enable_protection();
327 
328 	return ret;
329 }
330 
331 static asmlinkage void __exception_irq_entry
332 omap_intc_handle_irq(struct pt_regs *regs)
333 {
334 	u32 irqnr = 0;
335 	int handled_irq = 0;
336 	int i;
337 
338 	do {
339 		for (i = 0; i < omap_nr_pending; i++) {
340 			irqnr = intc_readl(INTC_PENDING_IRQ0 + (0x20 * i));
341 			if (irqnr)
342 				goto out;
343 		}
344 
345 out:
346 		if (!irqnr)
347 			break;
348 
349 		irqnr = intc_readl(INTC_SIR);
350 		irqnr &= ACTIVEIRQ_MASK;
351 
352 		if (irqnr) {
353 			handle_domain_irq(domain, irqnr, regs);
354 			handled_irq = 1;
355 		}
356 	} while (irqnr);
357 
358 	/*
359 	 * If an irq is masked or deasserted while active, we will
360 	 * keep ending up here with no irq handled. So remove it from
361 	 * the INTC with an ack.
362 	 */
363 	if (!handled_irq)
364 		omap_ack_irq(NULL);
365 }
366 
367 void __init omap3_init_irq(void)
368 {
369 	omap_nr_irqs = 96;
370 	omap_nr_pending = 3;
371 	omap_init_irq(OMAP34XX_IC_BASE, NULL);
372 	set_handle_irq(omap_intc_handle_irq);
373 }
374 
375 static int __init intc_of_init(struct device_node *node,
376 			     struct device_node *parent)
377 {
378 	int ret;
379 
380 	omap_nr_pending = 3;
381 	omap_nr_irqs = 96;
382 
383 	if (WARN_ON(!node))
384 		return -ENODEV;
385 
386 	if (of_device_is_compatible(node, "ti,dm814-intc") ||
387 	    of_device_is_compatible(node, "ti,dm816-intc") ||
388 	    of_device_is_compatible(node, "ti,am33xx-intc")) {
389 		omap_nr_irqs = 128;
390 		omap_nr_pending = 4;
391 	}
392 
393 	ret = omap_init_irq(-1, of_node_get(node));
394 	if (ret < 0)
395 		return ret;
396 
397 	set_handle_irq(omap_intc_handle_irq);
398 
399 	return 0;
400 }
401 
402 IRQCHIP_DECLARE(omap2_intc, "ti,omap2-intc", intc_of_init);
403 IRQCHIP_DECLARE(omap3_intc, "ti,omap3-intc", intc_of_init);
404 IRQCHIP_DECLARE(dm814x_intc, "ti,dm814-intc", intc_of_init);
405 IRQCHIP_DECLARE(dm816x_intc, "ti,dm816-intc", intc_of_init);
406 IRQCHIP_DECLARE(am33xx_intc, "ti,am33xx-intc", intc_of_init);
407