xref: /openbmc/linux/arch/mips/bcm63xx/irq.c (revision 54cbac81)
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_6328
31 #define irq_stat_reg		PERF_IRQSTAT_6328_REG
32 #define irq_mask_reg		PERF_IRQMASK_6328_REG
33 #define irq_bits		64
34 #define is_ext_irq_cascaded	1
35 #define ext_irq_start		(BCM_6328_EXT_IRQ0 - IRQ_INTERNAL_BASE)
36 #define ext_irq_end		(BCM_6328_EXT_IRQ3 - IRQ_INTERNAL_BASE)
37 #define ext_irq_count		4
38 #define ext_irq_cfg_reg1	PERF_EXTIRQ_CFG_REG_6328
39 #define ext_irq_cfg_reg2	0
40 #endif
41 #ifdef CONFIG_BCM63XX_CPU_6338
42 #define irq_stat_reg		PERF_IRQSTAT_6338_REG
43 #define irq_mask_reg		PERF_IRQMASK_6338_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		4
49 #define ext_irq_cfg_reg1	PERF_EXTIRQ_CFG_REG_6338
50 #define ext_irq_cfg_reg2	0
51 #endif
52 #ifdef CONFIG_BCM63XX_CPU_6345
53 #define irq_stat_reg		PERF_IRQSTAT_6345_REG
54 #define irq_mask_reg		PERF_IRQMASK_6345_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_6345
61 #define ext_irq_cfg_reg2	0
62 #endif
63 #ifdef CONFIG_BCM63XX_CPU_6348
64 #define irq_stat_reg		PERF_IRQSTAT_6348_REG
65 #define irq_mask_reg		PERF_IRQMASK_6348_REG
66 #define irq_bits		32
67 #define is_ext_irq_cascaded	0
68 #define ext_irq_start		0
69 #define ext_irq_end		0
70 #define ext_irq_count		4
71 #define ext_irq_cfg_reg1	PERF_EXTIRQ_CFG_REG_6348
72 #define ext_irq_cfg_reg2	0
73 #endif
74 #ifdef CONFIG_BCM63XX_CPU_6358
75 #define irq_stat_reg		PERF_IRQSTAT_6358_REG
76 #define irq_mask_reg		PERF_IRQMASK_6358_REG
77 #define irq_bits		32
78 #define is_ext_irq_cascaded	1
79 #define ext_irq_start		(BCM_6358_EXT_IRQ0 - IRQ_INTERNAL_BASE)
80 #define ext_irq_end		(BCM_6358_EXT_IRQ3 - IRQ_INTERNAL_BASE)
81 #define ext_irq_count		4
82 #define ext_irq_cfg_reg1	PERF_EXTIRQ_CFG_REG_6358
83 #define ext_irq_cfg_reg2	0
84 #endif
85 #ifdef CONFIG_BCM63XX_CPU_6368
86 #define irq_stat_reg		PERF_IRQSTAT_6368_REG
87 #define irq_mask_reg		PERF_IRQMASK_6368_REG
88 #define irq_bits		64
89 #define is_ext_irq_cascaded	1
90 #define ext_irq_start		(BCM_6368_EXT_IRQ0 - IRQ_INTERNAL_BASE)
91 #define ext_irq_end		(BCM_6368_EXT_IRQ5 - IRQ_INTERNAL_BASE)
92 #define ext_irq_count		6
93 #define ext_irq_cfg_reg1	PERF_EXTIRQ_CFG_REG_6368
94 #define ext_irq_cfg_reg2	PERF_EXTIRQ_CFG_REG2_6368
95 #endif
96 
97 #if irq_bits == 32
98 #define dispatch_internal			__dispatch_internal
99 #define internal_irq_mask			__internal_irq_mask_32
100 #define internal_irq_unmask			__internal_irq_unmask_32
101 #else
102 #define dispatch_internal			__dispatch_internal_64
103 #define internal_irq_mask			__internal_irq_mask_64
104 #define internal_irq_unmask			__internal_irq_unmask_64
105 #endif
106 
107 #define irq_stat_addr	(bcm63xx_regset_address(RSET_PERF) + irq_stat_reg)
108 #define irq_mask_addr	(bcm63xx_regset_address(RSET_PERF) + irq_mask_reg)
109 
110 static inline void bcm63xx_init_irq(void)
111 {
112 }
113 #else /* ! BCMCPU_RUNTIME_DETECT */
114 
115 static u32 irq_stat_addr, irq_mask_addr;
116 static void (*dispatch_internal)(void);
117 static int is_ext_irq_cascaded;
118 static unsigned int ext_irq_count;
119 static unsigned int ext_irq_start, ext_irq_end;
120 static unsigned int ext_irq_cfg_reg1, ext_irq_cfg_reg2;
121 static void (*internal_irq_mask)(unsigned int irq);
122 static void (*internal_irq_unmask)(unsigned int irq);
123 
124 static void bcm63xx_init_irq(void)
125 {
126 	int irq_bits;
127 
128 	irq_stat_addr = bcm63xx_regset_address(RSET_PERF);
129 	irq_mask_addr = bcm63xx_regset_address(RSET_PERF);
130 
131 	switch (bcm63xx_get_cpu_id()) {
132 	case BCM6328_CPU_ID:
133 		irq_stat_addr += PERF_IRQSTAT_6328_REG;
134 		irq_mask_addr += PERF_IRQMASK_6328_REG;
135 		irq_bits = 64;
136 		ext_irq_count = 4;
137 		is_ext_irq_cascaded = 1;
138 		ext_irq_start = BCM_6328_EXT_IRQ0 - IRQ_INTERNAL_BASE;
139 		ext_irq_end = BCM_6328_EXT_IRQ3 - IRQ_INTERNAL_BASE;
140 		ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6328;
141 		break;
142 	case BCM6338_CPU_ID:
143 		irq_stat_addr += PERF_IRQSTAT_6338_REG;
144 		irq_mask_addr += PERF_IRQMASK_6338_REG;
145 		irq_bits = 32;
146 		ext_irq_count = 4;
147 		ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6338;
148 		break;
149 	case BCM6345_CPU_ID:
150 		irq_stat_addr += PERF_IRQSTAT_6345_REG;
151 		irq_mask_addr += PERF_IRQMASK_6345_REG;
152 		irq_bits = 32;
153 		ext_irq_count = 4;
154 		ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6345;
155 		break;
156 	case BCM6348_CPU_ID:
157 		irq_stat_addr += PERF_IRQSTAT_6348_REG;
158 		irq_mask_addr += PERF_IRQMASK_6348_REG;
159 		irq_bits = 32;
160 		ext_irq_count = 4;
161 		ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6348;
162 		break;
163 	case BCM6358_CPU_ID:
164 		irq_stat_addr += PERF_IRQSTAT_6358_REG;
165 		irq_mask_addr += PERF_IRQMASK_6358_REG;
166 		irq_bits = 32;
167 		ext_irq_count = 4;
168 		is_ext_irq_cascaded = 1;
169 		ext_irq_start = BCM_6358_EXT_IRQ0 - IRQ_INTERNAL_BASE;
170 		ext_irq_end = BCM_6358_EXT_IRQ3 - IRQ_INTERNAL_BASE;
171 		ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6358;
172 		break;
173 	case BCM6368_CPU_ID:
174 		irq_stat_addr += PERF_IRQSTAT_6368_REG;
175 		irq_mask_addr += PERF_IRQMASK_6368_REG;
176 		irq_bits = 64;
177 		ext_irq_count = 6;
178 		is_ext_irq_cascaded = 1;
179 		ext_irq_start = BCM_6368_EXT_IRQ0 - IRQ_INTERNAL_BASE;
180 		ext_irq_end = BCM_6368_EXT_IRQ5 - IRQ_INTERNAL_BASE;
181 		ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6368;
182 		ext_irq_cfg_reg2 = PERF_EXTIRQ_CFG_REG2_6368;
183 		break;
184 	default:
185 		BUG();
186 	}
187 
188 	if (irq_bits == 32) {
189 		dispatch_internal = __dispatch_internal;
190 		internal_irq_mask = __internal_irq_mask_32;
191 		internal_irq_unmask = __internal_irq_unmask_32;
192 	} else {
193 		dispatch_internal = __dispatch_internal_64;
194 		internal_irq_mask = __internal_irq_mask_64;
195 		internal_irq_unmask = __internal_irq_unmask_64;
196 	}
197 }
198 #endif /* ! BCMCPU_RUNTIME_DETECT */
199 
200 static inline u32 get_ext_irq_perf_reg(int irq)
201 {
202 	if (irq < 4)
203 		return ext_irq_cfg_reg1;
204 	return ext_irq_cfg_reg2;
205 }
206 
207 static inline void handle_internal(int intbit)
208 {
209 	if (is_ext_irq_cascaded &&
210 	    intbit >= ext_irq_start && intbit <= ext_irq_end)
211 		do_IRQ(intbit - ext_irq_start + IRQ_EXTERNAL_BASE);
212 	else
213 		do_IRQ(intbit + IRQ_INTERNAL_BASE);
214 }
215 
216 /*
217  * dispatch internal devices IRQ (uart, enet, watchdog, ...). do not
218  * prioritize any interrupt relatively to another. the static counter
219  * will resume the loop where it ended the last time we left this
220  * function.
221  */
222 static void __dispatch_internal(void)
223 {
224 	u32 pending;
225 	static int i;
226 
227 	pending = bcm_readl(irq_stat_addr) & bcm_readl(irq_mask_addr);
228 
229 	if (!pending)
230 		return ;
231 
232 	while (1) {
233 		int to_call = i;
234 
235 		i = (i + 1) & 0x1f;
236 		if (pending & (1 << to_call)) {
237 			handle_internal(to_call);
238 			break;
239 		}
240 	}
241 }
242 
243 static void __dispatch_internal_64(void)
244 {
245 	u64 pending;
246 	static int i;
247 
248 	pending = bcm_readq(irq_stat_addr) & bcm_readq(irq_mask_addr);
249 
250 	if (!pending)
251 		return ;
252 
253 	while (1) {
254 		int to_call = i;
255 
256 		i = (i + 1) & 0x3f;
257 		if (pending & (1ull << to_call)) {
258 			handle_internal(to_call);
259 			break;
260 		}
261 	}
262 }
263 
264 asmlinkage void plat_irq_dispatch(void)
265 {
266 	u32 cause;
267 
268 	do {
269 		cause = read_c0_cause() & read_c0_status() & ST0_IM;
270 
271 		if (!cause)
272 			break;
273 
274 		if (cause & CAUSEF_IP7)
275 			do_IRQ(7);
276 		if (cause & CAUSEF_IP2)
277 			dispatch_internal();
278 		if (!is_ext_irq_cascaded) {
279 			if (cause & CAUSEF_IP3)
280 				do_IRQ(IRQ_EXT_0);
281 			if (cause & CAUSEF_IP4)
282 				do_IRQ(IRQ_EXT_1);
283 			if (cause & CAUSEF_IP5)
284 				do_IRQ(IRQ_EXT_2);
285 			if (cause & CAUSEF_IP6)
286 				do_IRQ(IRQ_EXT_3);
287 		}
288 	} while (1);
289 }
290 
291 /*
292  * internal IRQs operations: only mask/unmask on PERF irq mask
293  * register.
294  */
295 static void __internal_irq_mask_32(unsigned int irq)
296 {
297 	u32 mask;
298 
299 	mask = bcm_readl(irq_mask_addr);
300 	mask &= ~(1 << irq);
301 	bcm_writel(mask, irq_mask_addr);
302 }
303 
304 static void __internal_irq_mask_64(unsigned int irq)
305 {
306 	u64 mask;
307 
308 	mask = bcm_readq(irq_mask_addr);
309 	mask &= ~(1ull << irq);
310 	bcm_writeq(mask, irq_mask_addr);
311 }
312 
313 static void __internal_irq_unmask_32(unsigned int irq)
314 {
315 	u32 mask;
316 
317 	mask = bcm_readl(irq_mask_addr);
318 	mask |= (1 << irq);
319 	bcm_writel(mask, irq_mask_addr);
320 }
321 
322 static void __internal_irq_unmask_64(unsigned int irq)
323 {
324 	u64 mask;
325 
326 	mask = bcm_readq(irq_mask_addr);
327 	mask |= (1ull << irq);
328 	bcm_writeq(mask, irq_mask_addr);
329 }
330 
331 static void bcm63xx_internal_irq_mask(struct irq_data *d)
332 {
333 	internal_irq_mask(d->irq - IRQ_INTERNAL_BASE);
334 }
335 
336 static void bcm63xx_internal_irq_unmask(struct irq_data *d)
337 {
338 	internal_irq_unmask(d->irq - IRQ_INTERNAL_BASE);
339 }
340 
341 /*
342  * external IRQs operations: mask/unmask and clear on PERF external
343  * irq control register.
344  */
345 static void bcm63xx_external_irq_mask(struct irq_data *d)
346 {
347 	unsigned int irq = d->irq - IRQ_EXTERNAL_BASE;
348 	u32 reg, regaddr;
349 
350 	regaddr = get_ext_irq_perf_reg(irq);
351 	reg = bcm_perf_readl(regaddr);
352 
353 	if (BCMCPU_IS_6348())
354 		reg &= ~EXTIRQ_CFG_MASK_6348(irq % 4);
355 	else
356 		reg &= ~EXTIRQ_CFG_MASK(irq % 4);
357 
358 	bcm_perf_writel(reg, regaddr);
359 	if (is_ext_irq_cascaded)
360 		internal_irq_mask(irq + ext_irq_start);
361 }
362 
363 static void bcm63xx_external_irq_unmask(struct irq_data *d)
364 {
365 	unsigned int irq = d->irq - IRQ_EXTERNAL_BASE;
366 	u32 reg, regaddr;
367 
368 	regaddr = get_ext_irq_perf_reg(irq);
369 	reg = bcm_perf_readl(regaddr);
370 
371 	if (BCMCPU_IS_6348())
372 		reg |= EXTIRQ_CFG_MASK_6348(irq % 4);
373 	else
374 		reg |= EXTIRQ_CFG_MASK(irq % 4);
375 
376 	bcm_perf_writel(reg, regaddr);
377 
378 	if (is_ext_irq_cascaded)
379 		internal_irq_unmask(irq + ext_irq_start);
380 }
381 
382 static void bcm63xx_external_irq_clear(struct irq_data *d)
383 {
384 	unsigned int irq = d->irq - IRQ_EXTERNAL_BASE;
385 	u32 reg, regaddr;
386 
387 	regaddr = get_ext_irq_perf_reg(irq);
388 	reg = bcm_perf_readl(regaddr);
389 
390 	if (BCMCPU_IS_6348())
391 		reg |= EXTIRQ_CFG_CLEAR_6348(irq % 4);
392 	else
393 		reg |= EXTIRQ_CFG_CLEAR(irq % 4);
394 
395 	bcm_perf_writel(reg, regaddr);
396 }
397 
398 static int bcm63xx_external_irq_set_type(struct irq_data *d,
399 					 unsigned int flow_type)
400 {
401 	unsigned int irq = d->irq - IRQ_EXTERNAL_BASE;
402 	u32 reg, regaddr;
403 	int levelsense, sense, bothedge;
404 
405 	flow_type &= IRQ_TYPE_SENSE_MASK;
406 
407 	if (flow_type == IRQ_TYPE_NONE)
408 		flow_type = IRQ_TYPE_LEVEL_LOW;
409 
410 	levelsense = sense = bothedge = 0;
411 	switch (flow_type) {
412 	case IRQ_TYPE_EDGE_BOTH:
413 		bothedge = 1;
414 		break;
415 
416 	case IRQ_TYPE_EDGE_RISING:
417 		sense = 1;
418 		break;
419 
420 	case IRQ_TYPE_EDGE_FALLING:
421 		break;
422 
423 	case IRQ_TYPE_LEVEL_HIGH:
424 		levelsense = 1;
425 		sense = 1;
426 		break;
427 
428 	case IRQ_TYPE_LEVEL_LOW:
429 		levelsense = 1;
430 		break;
431 
432 	default:
433 		printk(KERN_ERR "bogus flow type combination given !\n");
434 		return -EINVAL;
435 	}
436 
437 	regaddr = get_ext_irq_perf_reg(irq);
438 	reg = bcm_perf_readl(regaddr);
439 	irq %= 4;
440 
441 	switch (bcm63xx_get_cpu_id()) {
442 	case BCM6348_CPU_ID:
443 		if (levelsense)
444 			reg |= EXTIRQ_CFG_LEVELSENSE_6348(irq);
445 		else
446 			reg &= ~EXTIRQ_CFG_LEVELSENSE_6348(irq);
447 		if (sense)
448 			reg |= EXTIRQ_CFG_SENSE_6348(irq);
449 		else
450 			reg &= ~EXTIRQ_CFG_SENSE_6348(irq);
451 		if (bothedge)
452 			reg |= EXTIRQ_CFG_BOTHEDGE_6348(irq);
453 		else
454 			reg &= ~EXTIRQ_CFG_BOTHEDGE_6348(irq);
455 		break;
456 
457 	case BCM6328_CPU_ID:
458 	case BCM6338_CPU_ID:
459 	case BCM6345_CPU_ID:
460 	case BCM6358_CPU_ID:
461 	case BCM6368_CPU_ID:
462 		if (levelsense)
463 			reg |= EXTIRQ_CFG_LEVELSENSE(irq);
464 		else
465 			reg &= ~EXTIRQ_CFG_LEVELSENSE(irq);
466 		if (sense)
467 			reg |= EXTIRQ_CFG_SENSE(irq);
468 		else
469 			reg &= ~EXTIRQ_CFG_SENSE(irq);
470 		if (bothedge)
471 			reg |= EXTIRQ_CFG_BOTHEDGE(irq);
472 		else
473 			reg &= ~EXTIRQ_CFG_BOTHEDGE(irq);
474 		break;
475 	default:
476 		BUG();
477 	}
478 
479 	bcm_perf_writel(reg, regaddr);
480 
481 	irqd_set_trigger_type(d, flow_type);
482 	if (flow_type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
483 		__irq_set_handler_locked(d->irq, handle_level_irq);
484 	else
485 		__irq_set_handler_locked(d->irq, handle_edge_irq);
486 
487 	return IRQ_SET_MASK_OK_NOCOPY;
488 }
489 
490 static struct irq_chip bcm63xx_internal_irq_chip = {
491 	.name		= "bcm63xx_ipic",
492 	.irq_mask	= bcm63xx_internal_irq_mask,
493 	.irq_unmask	= bcm63xx_internal_irq_unmask,
494 };
495 
496 static struct irq_chip bcm63xx_external_irq_chip = {
497 	.name		= "bcm63xx_epic",
498 	.irq_ack	= bcm63xx_external_irq_clear,
499 
500 	.irq_mask	= bcm63xx_external_irq_mask,
501 	.irq_unmask	= bcm63xx_external_irq_unmask,
502 
503 	.irq_set_type	= bcm63xx_external_irq_set_type,
504 };
505 
506 static struct irqaction cpu_ip2_cascade_action = {
507 	.handler	= no_action,
508 	.name		= "cascade_ip2",
509 	.flags		= IRQF_NO_THREAD,
510 };
511 
512 static struct irqaction cpu_ext_cascade_action = {
513 	.handler	= no_action,
514 	.name		= "cascade_extirq",
515 	.flags		= IRQF_NO_THREAD,
516 };
517 
518 void __init arch_init_irq(void)
519 {
520 	int i;
521 
522 	bcm63xx_init_irq();
523 	mips_cpu_irq_init();
524 	for (i = IRQ_INTERNAL_BASE; i < NR_IRQS; ++i)
525 		irq_set_chip_and_handler(i, &bcm63xx_internal_irq_chip,
526 					 handle_level_irq);
527 
528 	for (i = IRQ_EXTERNAL_BASE; i < IRQ_EXTERNAL_BASE + ext_irq_count; ++i)
529 		irq_set_chip_and_handler(i, &bcm63xx_external_irq_chip,
530 					 handle_edge_irq);
531 
532 	if (!is_ext_irq_cascaded) {
533 		for (i = 3; i < 3 + ext_irq_count; ++i)
534 			setup_irq(MIPS_CPU_IRQ_BASE + i, &cpu_ext_cascade_action);
535 	}
536 
537 	setup_irq(MIPS_CPU_IRQ_BASE + 2, &cpu_ip2_cascade_action);
538 }
539