xref: /linux/arch/mips/bcm63xx/irq.c (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
7  * Copyright (C) 2008 Nicolas Schichan <nschichan@freebox.fr>
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/module.h>
14 #include <linux/irq.h>
15 #include <asm/irq_cpu.h>
16 #include <asm/mipsregs.h>
17 #include <bcm63xx_cpu.h>
18 #include <bcm63xx_regs.h>
19 #include <bcm63xx_io.h>
20 #include <bcm63xx_irq.h>
21 
22 static void __dispatch_internal(void) __maybe_unused;
23 static void __dispatch_internal_64(void) __maybe_unused;
24 static void __internal_irq_mask_32(unsigned int irq) __maybe_unused;
25 static void __internal_irq_mask_64(unsigned int irq) __maybe_unused;
26 static void __internal_irq_unmask_32(unsigned int irq) __maybe_unused;
27 static void __internal_irq_unmask_64(unsigned int irq) __maybe_unused;
28 
29 #ifndef BCMCPU_RUNTIME_DETECT
30 #ifdef CONFIG_BCM63XX_CPU_6338
31 #define irq_stat_reg		PERF_IRQSTAT_6338_REG
32 #define irq_mask_reg		PERF_IRQMASK_6338_REG
33 #define irq_bits		32
34 #define is_ext_irq_cascaded	0
35 #define ext_irq_start		0
36 #define ext_irq_end		0
37 #define ext_irq_count		4
38 #define ext_irq_cfg_reg1	PERF_EXTIRQ_CFG_REG_6338
39 #define ext_irq_cfg_reg2	0
40 #endif
41 #ifdef CONFIG_BCM63XX_CPU_6345
42 #define irq_stat_reg		PERF_IRQSTAT_6345_REG
43 #define irq_mask_reg		PERF_IRQMASK_6345_REG
44 #define irq_bits		32
45 #define is_ext_irq_cascaded	0
46 #define ext_irq_start		0
47 #define ext_irq_end		0
48 #define ext_irq_count		0
49 #define ext_irq_cfg_reg1	0
50 #define ext_irq_cfg_reg2	0
51 #endif
52 #ifdef CONFIG_BCM63XX_CPU_6348
53 #define irq_stat_reg		PERF_IRQSTAT_6348_REG
54 #define irq_mask_reg		PERF_IRQMASK_6348_REG
55 #define irq_bits		32
56 #define is_ext_irq_cascaded	0
57 #define ext_irq_start		0
58 #define ext_irq_end		0
59 #define ext_irq_count		4
60 #define ext_irq_cfg_reg1	PERF_EXTIRQ_CFG_REG_6348
61 #define ext_irq_cfg_reg2	0
62 #endif
63 #ifdef CONFIG_BCM63XX_CPU_6358
64 #define irq_stat_reg		PERF_IRQSTAT_6358_REG
65 #define irq_mask_reg		PERF_IRQMASK_6358_REG
66 #define irq_bits		32
67 #define is_ext_irq_cascaded	1
68 #define ext_irq_start		(BCM_6358_EXT_IRQ0 - IRQ_INTERNAL_BASE)
69 #define ext_irq_end		(BCM_6358_EXT_IRQ3 - IRQ_INTERNAL_BASE)
70 #define ext_irq_count		4
71 #define ext_irq_cfg_reg1	PERF_EXTIRQ_CFG_REG_6358
72 #define ext_irq_cfg_reg2	0
73 #endif
74 #ifdef CONFIG_BCM63XX_CPU_6368
75 #define irq_stat_reg		PERF_IRQSTAT_6368_REG
76 #define irq_mask_reg		PERF_IRQMASK_6368_REG
77 #define irq_bits		64
78 #define is_ext_irq_cascaded	1
79 #define ext_irq_start		(BCM_6368_EXT_IRQ0 - IRQ_INTERNAL_BASE)
80 #define ext_irq_end		(BCM_6368_EXT_IRQ5 - IRQ_INTERNAL_BASE)
81 #define ext_irq_count		6
82 #define ext_irq_cfg_reg1	PERF_EXTIRQ_CFG_REG_6368
83 #define ext_irq_cfg_reg2	PERF_EXTIRQ_CFG_REG2_6368
84 #endif
85 
86 #if irq_bits == 32
87 #define dispatch_internal			__dispatch_internal
88 #define internal_irq_mask			__internal_irq_mask_32
89 #define internal_irq_unmask			__internal_irq_unmask_32
90 #else
91 #define dispatch_internal			__dispatch_internal_64
92 #define internal_irq_mask			__internal_irq_mask_64
93 #define internal_irq_unmask			__internal_irq_unmask_64
94 #endif
95 
96 #define irq_stat_addr	(bcm63xx_regset_address(RSET_PERF) + irq_stat_reg)
97 #define irq_mask_addr	(bcm63xx_regset_address(RSET_PERF) + irq_mask_reg)
98 
99 static inline void bcm63xx_init_irq(void)
100 {
101 }
102 #else /* ! BCMCPU_RUNTIME_DETECT */
103 
104 static u32 irq_stat_addr, irq_mask_addr;
105 static void (*dispatch_internal)(void);
106 static int is_ext_irq_cascaded;
107 static unsigned int ext_irq_count;
108 static unsigned int ext_irq_start, ext_irq_end;
109 static unsigned int ext_irq_cfg_reg1, ext_irq_cfg_reg2;
110 static void (*internal_irq_mask)(unsigned int irq);
111 static void (*internal_irq_unmask)(unsigned int irq);
112 
113 static void bcm63xx_init_irq(void)
114 {
115 	int irq_bits;
116 
117 	irq_stat_addr = bcm63xx_regset_address(RSET_PERF);
118 	irq_mask_addr = bcm63xx_regset_address(RSET_PERF);
119 
120 	switch (bcm63xx_get_cpu_id()) {
121 	case BCM6338_CPU_ID:
122 		irq_stat_addr += PERF_IRQSTAT_6338_REG;
123 		irq_mask_addr += PERF_IRQMASK_6338_REG;
124 		irq_bits = 32;
125 		break;
126 	case BCM6345_CPU_ID:
127 		irq_stat_addr += PERF_IRQSTAT_6345_REG;
128 		irq_mask_addr += PERF_IRQMASK_6345_REG;
129 		irq_bits = 32;
130 		break;
131 	case BCM6348_CPU_ID:
132 		irq_stat_addr += PERF_IRQSTAT_6348_REG;
133 		irq_mask_addr += PERF_IRQMASK_6348_REG;
134 		irq_bits = 32;
135 		ext_irq_count = 4;
136 		ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6348;
137 		break;
138 	case BCM6358_CPU_ID:
139 		irq_stat_addr += PERF_IRQSTAT_6358_REG;
140 		irq_mask_addr += PERF_IRQMASK_6358_REG;
141 		irq_bits = 32;
142 		ext_irq_count = 4;
143 		is_ext_irq_cascaded = 1;
144 		ext_irq_start = BCM_6358_EXT_IRQ0 - IRQ_INTERNAL_BASE;
145 		ext_irq_end = BCM_6358_EXT_IRQ3 - IRQ_INTERNAL_BASE;
146 		ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6358;
147 		break;
148 	case BCM6368_CPU_ID:
149 		irq_stat_addr += PERF_IRQSTAT_6368_REG;
150 		irq_mask_addr += PERF_IRQMASK_6368_REG;
151 		irq_bits = 64;
152 		ext_irq_count = 6;
153 		is_ext_irq_cascaded = 1;
154 		ext_irq_start = BCM_6368_EXT_IRQ0 - IRQ_INTERNAL_BASE;
155 		ext_irq_end = BCM_6368_EXT_IRQ5 - IRQ_INTERNAL_BASE;
156 		ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6368;
157 		ext_irq_cfg_reg2 = PERF_EXTIRQ_CFG_REG2_6368;
158 		break;
159 	default:
160 		BUG();
161 	}
162 
163 	if (irq_bits == 32) {
164 		dispatch_internal = __dispatch_internal;
165 		internal_irq_mask = __internal_irq_mask_32;
166 		internal_irq_unmask = __internal_irq_unmask_32;
167 	} else {
168 		dispatch_internal = __dispatch_internal_64;
169 		internal_irq_mask = __internal_irq_mask_64;
170 		internal_irq_unmask = __internal_irq_unmask_64;
171 	}
172 }
173 #endif /* ! BCMCPU_RUNTIME_DETECT */
174 
175 static inline u32 get_ext_irq_perf_reg(int irq)
176 {
177 	if (irq < 4)
178 		return ext_irq_cfg_reg1;
179 	return ext_irq_cfg_reg2;
180 }
181 
182 static inline void handle_internal(int intbit)
183 {
184 	if (is_ext_irq_cascaded &&
185 	    intbit >= ext_irq_start && intbit <= ext_irq_end)
186 		do_IRQ(intbit - ext_irq_start + IRQ_EXTERNAL_BASE);
187 	else
188 		do_IRQ(intbit + IRQ_INTERNAL_BASE);
189 }
190 
191 /*
192  * dispatch internal devices IRQ (uart, enet, watchdog, ...). do not
193  * prioritize any interrupt relatively to another. the static counter
194  * will resume the loop where it ended the last time we left this
195  * function.
196  */
197 static void __dispatch_internal(void)
198 {
199 	u32 pending;
200 	static int i;
201 
202 	pending = bcm_readl(irq_stat_addr) & bcm_readl(irq_mask_addr);
203 
204 	if (!pending)
205 		return ;
206 
207 	while (1) {
208 		int to_call = i;
209 
210 		i = (i + 1) & 0x1f;
211 		if (pending & (1 << to_call)) {
212 			handle_internal(to_call);
213 			break;
214 		}
215 	}
216 }
217 
218 static void __dispatch_internal_64(void)
219 {
220 	u64 pending;
221 	static int i;
222 
223 	pending = bcm_readq(irq_stat_addr) & bcm_readq(irq_mask_addr);
224 
225 	if (!pending)
226 		return ;
227 
228 	while (1) {
229 		int to_call = i;
230 
231 		i = (i + 1) & 0x3f;
232 		if (pending & (1ull << to_call)) {
233 			handle_internal(to_call);
234 			break;
235 		}
236 	}
237 }
238 
239 asmlinkage void plat_irq_dispatch(void)
240 {
241 	u32 cause;
242 
243 	do {
244 		cause = read_c0_cause() & read_c0_status() & ST0_IM;
245 
246 		if (!cause)
247 			break;
248 
249 		if (cause & CAUSEF_IP7)
250 			do_IRQ(7);
251 		if (cause & CAUSEF_IP2)
252 			dispatch_internal();
253 		if (!is_ext_irq_cascaded) {
254 			if (cause & CAUSEF_IP3)
255 				do_IRQ(IRQ_EXT_0);
256 			if (cause & CAUSEF_IP4)
257 				do_IRQ(IRQ_EXT_1);
258 			if (cause & CAUSEF_IP5)
259 				do_IRQ(IRQ_EXT_2);
260 			if (cause & CAUSEF_IP6)
261 				do_IRQ(IRQ_EXT_3);
262 		}
263 	} while (1);
264 }
265 
266 /*
267  * internal IRQs operations: only mask/unmask on PERF irq mask
268  * register.
269  */
270 static void __internal_irq_mask_32(unsigned int irq)
271 {
272 	u32 mask;
273 
274 	mask = bcm_readl(irq_mask_addr);
275 	mask &= ~(1 << irq);
276 	bcm_writel(mask, irq_mask_addr);
277 }
278 
279 static void __internal_irq_mask_64(unsigned int irq)
280 {
281 	u64 mask;
282 
283 	mask = bcm_readq(irq_mask_addr);
284 	mask &= ~(1ull << irq);
285 	bcm_writeq(mask, irq_mask_addr);
286 }
287 
288 static void __internal_irq_unmask_32(unsigned int irq)
289 {
290 	u32 mask;
291 
292 	mask = bcm_readl(irq_mask_addr);
293 	mask |= (1 << irq);
294 	bcm_writel(mask, irq_mask_addr);
295 }
296 
297 static void __internal_irq_unmask_64(unsigned int irq)
298 {
299 	u64 mask;
300 
301 	mask = bcm_readq(irq_mask_addr);
302 	mask |= (1ull << irq);
303 	bcm_writeq(mask, irq_mask_addr);
304 }
305 
306 static void bcm63xx_internal_irq_mask(struct irq_data *d)
307 {
308 	internal_irq_mask(d->irq - IRQ_INTERNAL_BASE);
309 }
310 
311 static void bcm63xx_internal_irq_unmask(struct irq_data *d)
312 {
313 	internal_irq_unmask(d->irq - IRQ_INTERNAL_BASE);
314 }
315 
316 /*
317  * external IRQs operations: mask/unmask and clear on PERF external
318  * irq control register.
319  */
320 static void bcm63xx_external_irq_mask(struct irq_data *d)
321 {
322 	unsigned int irq = d->irq - IRQ_EXTERNAL_BASE;
323 	u32 reg, regaddr;
324 
325 	regaddr = get_ext_irq_perf_reg(irq);
326 	reg = bcm_perf_readl(regaddr);
327 
328 	if (BCMCPU_IS_6348())
329 		reg &= ~EXTIRQ_CFG_MASK_6348(irq % 4);
330 	else
331 		reg &= ~EXTIRQ_CFG_MASK(irq % 4);
332 
333 	bcm_perf_writel(reg, regaddr);
334 	if (is_ext_irq_cascaded)
335 		internal_irq_mask(irq + ext_irq_start);
336 }
337 
338 static void bcm63xx_external_irq_unmask(struct irq_data *d)
339 {
340 	unsigned int irq = d->irq - IRQ_EXTERNAL_BASE;
341 	u32 reg, regaddr;
342 
343 	regaddr = get_ext_irq_perf_reg(irq);
344 	reg = bcm_perf_readl(regaddr);
345 
346 	if (BCMCPU_IS_6348())
347 		reg |= EXTIRQ_CFG_MASK_6348(irq % 4);
348 	else
349 		reg |= EXTIRQ_CFG_MASK(irq % 4);
350 
351 	bcm_perf_writel(reg, regaddr);
352 
353 	if (is_ext_irq_cascaded)
354 		internal_irq_unmask(irq + ext_irq_start);
355 }
356 
357 static void bcm63xx_external_irq_clear(struct irq_data *d)
358 {
359 	unsigned int irq = d->irq - IRQ_EXTERNAL_BASE;
360 	u32 reg, regaddr;
361 
362 	regaddr = get_ext_irq_perf_reg(irq);
363 	reg = bcm_perf_readl(regaddr);
364 
365 	if (BCMCPU_IS_6348())
366 		reg |= EXTIRQ_CFG_CLEAR_6348(irq % 4);
367 	else
368 		reg |= EXTIRQ_CFG_CLEAR(irq % 4);
369 
370 	bcm_perf_writel(reg, regaddr);
371 }
372 
373 static int bcm63xx_external_irq_set_type(struct irq_data *d,
374 					 unsigned int flow_type)
375 {
376 	unsigned int irq = d->irq - IRQ_EXTERNAL_BASE;
377 	u32 reg, regaddr;
378 	int levelsense, sense, bothedge;
379 
380 	flow_type &= IRQ_TYPE_SENSE_MASK;
381 
382 	if (flow_type == IRQ_TYPE_NONE)
383 		flow_type = IRQ_TYPE_LEVEL_LOW;
384 
385 	levelsense = sense = bothedge = 0;
386 	switch (flow_type) {
387 	case IRQ_TYPE_EDGE_BOTH:
388 		bothedge = 1;
389 		break;
390 
391 	case IRQ_TYPE_EDGE_RISING:
392 		sense = 1;
393 		break;
394 
395 	case IRQ_TYPE_EDGE_FALLING:
396 		break;
397 
398 	case IRQ_TYPE_LEVEL_HIGH:
399 		levelsense = 1;
400 		sense = 1;
401 		break;
402 
403 	case IRQ_TYPE_LEVEL_LOW:
404 		levelsense = 1;
405 		break;
406 
407 	default:
408 		printk(KERN_ERR "bogus flow type combination given !\n");
409 		return -EINVAL;
410 	}
411 
412 	regaddr = get_ext_irq_perf_reg(irq);
413 	reg = bcm_perf_readl(regaddr);
414 	irq %= 4;
415 
416 	if (BCMCPU_IS_6348()) {
417 		if (levelsense)
418 			reg |= EXTIRQ_CFG_LEVELSENSE_6348(irq);
419 		else
420 			reg &= ~EXTIRQ_CFG_LEVELSENSE_6348(irq);
421 		if (sense)
422 			reg |= EXTIRQ_CFG_SENSE_6348(irq);
423 		else
424 			reg &= ~EXTIRQ_CFG_SENSE_6348(irq);
425 		if (bothedge)
426 			reg |= EXTIRQ_CFG_BOTHEDGE_6348(irq);
427 		else
428 			reg &= ~EXTIRQ_CFG_BOTHEDGE_6348(irq);
429 	}
430 
431 	if (BCMCPU_IS_6338() || BCMCPU_IS_6358() || BCMCPU_IS_6368()) {
432 		if (levelsense)
433 			reg |= EXTIRQ_CFG_LEVELSENSE(irq);
434 		else
435 			reg &= ~EXTIRQ_CFG_LEVELSENSE(irq);
436 		if (sense)
437 			reg |= EXTIRQ_CFG_SENSE(irq);
438 		else
439 			reg &= ~EXTIRQ_CFG_SENSE(irq);
440 		if (bothedge)
441 			reg |= EXTIRQ_CFG_BOTHEDGE(irq);
442 		else
443 			reg &= ~EXTIRQ_CFG_BOTHEDGE(irq);
444 	}
445 
446 	bcm_perf_writel(reg, regaddr);
447 
448 	irqd_set_trigger_type(d, flow_type);
449 	if (flow_type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
450 		__irq_set_handler_locked(d->irq, handle_level_irq);
451 	else
452 		__irq_set_handler_locked(d->irq, handle_edge_irq);
453 
454 	return IRQ_SET_MASK_OK_NOCOPY;
455 }
456 
457 static struct irq_chip bcm63xx_internal_irq_chip = {
458 	.name		= "bcm63xx_ipic",
459 	.irq_mask	= bcm63xx_internal_irq_mask,
460 	.irq_unmask	= bcm63xx_internal_irq_unmask,
461 };
462 
463 static struct irq_chip bcm63xx_external_irq_chip = {
464 	.name		= "bcm63xx_epic",
465 	.irq_ack	= bcm63xx_external_irq_clear,
466 
467 	.irq_mask	= bcm63xx_external_irq_mask,
468 	.irq_unmask	= bcm63xx_external_irq_unmask,
469 
470 	.irq_set_type	= bcm63xx_external_irq_set_type,
471 };
472 
473 static struct irqaction cpu_ip2_cascade_action = {
474 	.handler	= no_action,
475 	.name		= "cascade_ip2",
476 	.flags		= IRQF_NO_THREAD,
477 };
478 
479 static struct irqaction cpu_ext_cascade_action = {
480 	.handler	= no_action,
481 	.name		= "cascade_extirq",
482 	.flags		= IRQF_NO_THREAD,
483 };
484 
485 void __init arch_init_irq(void)
486 {
487 	int i;
488 
489 	bcm63xx_init_irq();
490 	mips_cpu_irq_init();
491 	for (i = IRQ_INTERNAL_BASE; i < NR_IRQS; ++i)
492 		irq_set_chip_and_handler(i, &bcm63xx_internal_irq_chip,
493 					 handle_level_irq);
494 
495 	for (i = IRQ_EXTERNAL_BASE; i < IRQ_EXTERNAL_BASE + ext_irq_count; ++i)
496 		irq_set_chip_and_handler(i, &bcm63xx_external_irq_chip,
497 					 handle_edge_irq);
498 
499 	if (!is_ext_irq_cascaded) {
500 		for (i = 3; i < 3 + ext_irq_count; ++i)
501 			setup_irq(MIPS_CPU_IRQ_BASE + i, &cpu_ext_cascade_action);
502 	}
503 
504 	setup_irq(MIPS_CPU_IRQ_BASE + 2, &cpu_ip2_cascade_action);
505 }
506