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 Ralf Baechle (ralf@linux-mips.org)
7  * Copyright (C) 2012 MIPS Technologies, Inc.  All rights reserved.
8  */
9 #include <linux/bitmap.h>
10 #include <linux/clocksource.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/irq.h>
14 #include <linux/irqchip.h>
15 #include <linux/irqchip/mips-gic.h>
16 #include <linux/of_address.h>
17 #include <linux/sched.h>
18 #include <linux/smp.h>
19 
20 #include <asm/mips-cm.h>
21 #include <asm/setup.h>
22 #include <asm/traps.h>
23 
24 #include <dt-bindings/interrupt-controller/mips-gic.h>
25 
26 unsigned int gic_present;
27 
28 struct gic_pcpu_mask {
29 	DECLARE_BITMAP(pcpu_mask, GIC_MAX_INTRS);
30 };
31 
32 static unsigned long __gic_base_addr;
33 static void __iomem *gic_base;
34 static struct gic_pcpu_mask pcpu_masks[NR_CPUS];
35 static DEFINE_SPINLOCK(gic_lock);
36 static struct irq_domain *gic_irq_domain;
37 static int gic_shared_intrs;
38 static int gic_vpes;
39 static unsigned int gic_cpu_pin;
40 static unsigned int timer_cpu_pin;
41 static struct irq_chip gic_level_irq_controller, gic_edge_irq_controller;
42 
43 static void __gic_irq_dispatch(void);
44 
45 static inline u32 gic_read32(unsigned int reg)
46 {
47 	return __raw_readl(gic_base + reg);
48 }
49 
50 static inline u64 gic_read64(unsigned int reg)
51 {
52 	return __raw_readq(gic_base + reg);
53 }
54 
55 static inline unsigned long gic_read(unsigned int reg)
56 {
57 	if (!mips_cm_is64)
58 		return gic_read32(reg);
59 	else
60 		return gic_read64(reg);
61 }
62 
63 static inline void gic_write32(unsigned int reg, u32 val)
64 {
65 	return __raw_writel(val, gic_base + reg);
66 }
67 
68 static inline void gic_write64(unsigned int reg, u64 val)
69 {
70 	return __raw_writeq(val, gic_base + reg);
71 }
72 
73 static inline void gic_write(unsigned int reg, unsigned long val)
74 {
75 	if (!mips_cm_is64)
76 		return gic_write32(reg, (u32)val);
77 	else
78 		return gic_write64(reg, (u64)val);
79 }
80 
81 static inline void gic_update_bits(unsigned int reg, unsigned long mask,
82 				   unsigned long val)
83 {
84 	unsigned long regval;
85 
86 	regval = gic_read(reg);
87 	regval &= ~mask;
88 	regval |= val;
89 	gic_write(reg, regval);
90 }
91 
92 static inline void gic_reset_mask(unsigned int intr)
93 {
94 	gic_write(GIC_REG(SHARED, GIC_SH_RMASK) + GIC_INTR_OFS(intr),
95 		  1ul << GIC_INTR_BIT(intr));
96 }
97 
98 static inline void gic_set_mask(unsigned int intr)
99 {
100 	gic_write(GIC_REG(SHARED, GIC_SH_SMASK) + GIC_INTR_OFS(intr),
101 		  1ul << GIC_INTR_BIT(intr));
102 }
103 
104 static inline void gic_set_polarity(unsigned int intr, unsigned int pol)
105 {
106 	gic_update_bits(GIC_REG(SHARED, GIC_SH_SET_POLARITY) +
107 			GIC_INTR_OFS(intr), 1ul << GIC_INTR_BIT(intr),
108 			(unsigned long)pol << GIC_INTR_BIT(intr));
109 }
110 
111 static inline void gic_set_trigger(unsigned int intr, unsigned int trig)
112 {
113 	gic_update_bits(GIC_REG(SHARED, GIC_SH_SET_TRIGGER) +
114 			GIC_INTR_OFS(intr), 1ul << GIC_INTR_BIT(intr),
115 			(unsigned long)trig << GIC_INTR_BIT(intr));
116 }
117 
118 static inline void gic_set_dual_edge(unsigned int intr, unsigned int dual)
119 {
120 	gic_update_bits(GIC_REG(SHARED, GIC_SH_SET_DUAL) + GIC_INTR_OFS(intr),
121 			1ul << GIC_INTR_BIT(intr),
122 			(unsigned long)dual << GIC_INTR_BIT(intr));
123 }
124 
125 static inline void gic_map_to_pin(unsigned int intr, unsigned int pin)
126 {
127 	gic_write32(GIC_REG(SHARED, GIC_SH_INTR_MAP_TO_PIN_BASE) +
128 		    GIC_SH_MAP_TO_PIN(intr), GIC_MAP_TO_PIN_MSK | pin);
129 }
130 
131 static inline void gic_map_to_vpe(unsigned int intr, unsigned int vpe)
132 {
133 	gic_write(GIC_REG(SHARED, GIC_SH_INTR_MAP_TO_VPE_BASE) +
134 		  GIC_SH_MAP_TO_VPE_REG_OFF(intr, vpe),
135 		  GIC_SH_MAP_TO_VPE_REG_BIT(vpe));
136 }
137 
138 #ifdef CONFIG_CLKSRC_MIPS_GIC
139 cycle_t gic_read_count(void)
140 {
141 	unsigned int hi, hi2, lo;
142 
143 	if (mips_cm_is64)
144 		return (cycle_t)gic_read(GIC_REG(SHARED, GIC_SH_COUNTER));
145 
146 	do {
147 		hi = gic_read32(GIC_REG(SHARED, GIC_SH_COUNTER_63_32));
148 		lo = gic_read32(GIC_REG(SHARED, GIC_SH_COUNTER_31_00));
149 		hi2 = gic_read32(GIC_REG(SHARED, GIC_SH_COUNTER_63_32));
150 	} while (hi2 != hi);
151 
152 	return (((cycle_t) hi) << 32) + lo;
153 }
154 
155 unsigned int gic_get_count_width(void)
156 {
157 	unsigned int bits, config;
158 
159 	config = gic_read(GIC_REG(SHARED, GIC_SH_CONFIG));
160 	bits = 32 + 4 * ((config & GIC_SH_CONFIG_COUNTBITS_MSK) >>
161 			 GIC_SH_CONFIG_COUNTBITS_SHF);
162 
163 	return bits;
164 }
165 
166 void gic_write_compare(cycle_t cnt)
167 {
168 	if (mips_cm_is64) {
169 		gic_write(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE), cnt);
170 	} else {
171 		gic_write32(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_HI),
172 					(int)(cnt >> 32));
173 		gic_write32(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_LO),
174 					(int)(cnt & 0xffffffff));
175 	}
176 }
177 
178 void gic_write_cpu_compare(cycle_t cnt, int cpu)
179 {
180 	unsigned long flags;
181 
182 	local_irq_save(flags);
183 
184 	gic_write(GIC_REG(VPE_LOCAL, GIC_VPE_OTHER_ADDR), cpu);
185 
186 	if (mips_cm_is64) {
187 		gic_write(GIC_REG(VPE_OTHER, GIC_VPE_COMPARE), cnt);
188 	} else {
189 		gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_COMPARE_HI),
190 					(int)(cnt >> 32));
191 		gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_COMPARE_LO),
192 					(int)(cnt & 0xffffffff));
193 	}
194 
195 	local_irq_restore(flags);
196 }
197 
198 cycle_t gic_read_compare(void)
199 {
200 	unsigned int hi, lo;
201 
202 	if (mips_cm_is64)
203 		return (cycle_t)gic_read(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE));
204 
205 	hi = gic_read32(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_HI));
206 	lo = gic_read32(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_LO));
207 
208 	return (((cycle_t) hi) << 32) + lo;
209 }
210 
211 void gic_start_count(void)
212 {
213 	u32 gicconfig;
214 
215 	/* Start the counter */
216 	gicconfig = gic_read(GIC_REG(SHARED, GIC_SH_CONFIG));
217 	gicconfig &= ~(1 << GIC_SH_CONFIG_COUNTSTOP_SHF);
218 	gic_write(GIC_REG(SHARED, GIC_SH_CONFIG), gicconfig);
219 }
220 
221 void gic_stop_count(void)
222 {
223 	u32 gicconfig;
224 
225 	/* Stop the counter */
226 	gicconfig = gic_read(GIC_REG(SHARED, GIC_SH_CONFIG));
227 	gicconfig |= 1 << GIC_SH_CONFIG_COUNTSTOP_SHF;
228 	gic_write(GIC_REG(SHARED, GIC_SH_CONFIG), gicconfig);
229 }
230 
231 #endif
232 
233 static bool gic_local_irq_is_routable(int intr)
234 {
235 	u32 vpe_ctl;
236 
237 	/* All local interrupts are routable in EIC mode. */
238 	if (cpu_has_veic)
239 		return true;
240 
241 	vpe_ctl = gic_read32(GIC_REG(VPE_LOCAL, GIC_VPE_CTL));
242 	switch (intr) {
243 	case GIC_LOCAL_INT_TIMER:
244 		return vpe_ctl & GIC_VPE_CTL_TIMER_RTBL_MSK;
245 	case GIC_LOCAL_INT_PERFCTR:
246 		return vpe_ctl & GIC_VPE_CTL_PERFCNT_RTBL_MSK;
247 	case GIC_LOCAL_INT_FDC:
248 		return vpe_ctl & GIC_VPE_CTL_FDC_RTBL_MSK;
249 	case GIC_LOCAL_INT_SWINT0:
250 	case GIC_LOCAL_INT_SWINT1:
251 		return vpe_ctl & GIC_VPE_CTL_SWINT_RTBL_MSK;
252 	default:
253 		return true;
254 	}
255 }
256 
257 static void gic_bind_eic_interrupt(int irq, int set)
258 {
259 	/* Convert irq vector # to hw int # */
260 	irq -= GIC_PIN_TO_VEC_OFFSET;
261 
262 	/* Set irq to use shadow set */
263 	gic_write(GIC_REG(VPE_LOCAL, GIC_VPE_EIC_SHADOW_SET_BASE) +
264 		  GIC_VPE_EIC_SS(irq), set);
265 }
266 
267 void gic_send_ipi(unsigned int intr)
268 {
269 	gic_write(GIC_REG(SHARED, GIC_SH_WEDGE), GIC_SH_WEDGE_SET(intr));
270 }
271 
272 int gic_get_c0_compare_int(void)
273 {
274 	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_TIMER))
275 		return MIPS_CPU_IRQ_BASE + cp0_compare_irq;
276 	return irq_create_mapping(gic_irq_domain,
277 				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_TIMER));
278 }
279 
280 int gic_get_c0_perfcount_int(void)
281 {
282 	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_PERFCTR)) {
283 		/* Is the performance counter shared with the timer? */
284 		if (cp0_perfcount_irq < 0)
285 			return -1;
286 		return MIPS_CPU_IRQ_BASE + cp0_perfcount_irq;
287 	}
288 	return irq_create_mapping(gic_irq_domain,
289 				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_PERFCTR));
290 }
291 
292 int gic_get_c0_fdc_int(void)
293 {
294 	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_FDC)) {
295 		/* Is the FDC IRQ even present? */
296 		if (cp0_fdc_irq < 0)
297 			return -1;
298 		return MIPS_CPU_IRQ_BASE + cp0_fdc_irq;
299 	}
300 
301 	return irq_create_mapping(gic_irq_domain,
302 				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_FDC));
303 }
304 
305 int gic_get_usm_range(struct resource *gic_usm_res)
306 {
307 	if (!gic_present)
308 		return -1;
309 
310 	gic_usm_res->start = __gic_base_addr + USM_VISIBLE_SECTION_OFS;
311 	gic_usm_res->end = gic_usm_res->start + (USM_VISIBLE_SECTION_SIZE - 1);
312 
313 	return 0;
314 }
315 
316 static void gic_handle_shared_int(bool chained)
317 {
318 	unsigned int i, intr, virq, gic_reg_step = mips_cm_is64 ? 8 : 4;
319 	unsigned long *pcpu_mask;
320 	unsigned long pending_reg, intrmask_reg;
321 	DECLARE_BITMAP(pending, GIC_MAX_INTRS);
322 	DECLARE_BITMAP(intrmask, GIC_MAX_INTRS);
323 
324 	/* Get per-cpu bitmaps */
325 	pcpu_mask = pcpu_masks[smp_processor_id()].pcpu_mask;
326 
327 	pending_reg = GIC_REG(SHARED, GIC_SH_PEND);
328 	intrmask_reg = GIC_REG(SHARED, GIC_SH_MASK);
329 
330 	for (i = 0; i < BITS_TO_LONGS(gic_shared_intrs); i++) {
331 		pending[i] = gic_read(pending_reg);
332 		intrmask[i] = gic_read(intrmask_reg);
333 		pending_reg += gic_reg_step;
334 		intrmask_reg += gic_reg_step;
335 
336 		if (!config_enabled(CONFIG_64BIT) || mips_cm_is64)
337 			continue;
338 
339 		pending[i] |= (u64)gic_read(pending_reg) << 32;
340 		intrmask[i] |= (u64)gic_read(intrmask_reg) << 32;
341 		pending_reg += gic_reg_step;
342 		intrmask_reg += gic_reg_step;
343 	}
344 
345 	bitmap_and(pending, pending, intrmask, gic_shared_intrs);
346 	bitmap_and(pending, pending, pcpu_mask, gic_shared_intrs);
347 
348 	intr = find_first_bit(pending, gic_shared_intrs);
349 	while (intr != gic_shared_intrs) {
350 		virq = irq_linear_revmap(gic_irq_domain,
351 					 GIC_SHARED_TO_HWIRQ(intr));
352 		if (chained)
353 			generic_handle_irq(virq);
354 		else
355 			do_IRQ(virq);
356 
357 		/* go to next pending bit */
358 		bitmap_clear(pending, intr, 1);
359 		intr = find_first_bit(pending, gic_shared_intrs);
360 	}
361 }
362 
363 static void gic_mask_irq(struct irq_data *d)
364 {
365 	gic_reset_mask(GIC_HWIRQ_TO_SHARED(d->hwirq));
366 }
367 
368 static void gic_unmask_irq(struct irq_data *d)
369 {
370 	gic_set_mask(GIC_HWIRQ_TO_SHARED(d->hwirq));
371 }
372 
373 static void gic_ack_irq(struct irq_data *d)
374 {
375 	unsigned int irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
376 
377 	gic_write(GIC_REG(SHARED, GIC_SH_WEDGE), GIC_SH_WEDGE_CLR(irq));
378 }
379 
380 static int gic_set_type(struct irq_data *d, unsigned int type)
381 {
382 	unsigned int irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
383 	unsigned long flags;
384 	bool is_edge;
385 
386 	spin_lock_irqsave(&gic_lock, flags);
387 	switch (type & IRQ_TYPE_SENSE_MASK) {
388 	case IRQ_TYPE_EDGE_FALLING:
389 		gic_set_polarity(irq, GIC_POL_NEG);
390 		gic_set_trigger(irq, GIC_TRIG_EDGE);
391 		gic_set_dual_edge(irq, GIC_TRIG_DUAL_DISABLE);
392 		is_edge = true;
393 		break;
394 	case IRQ_TYPE_EDGE_RISING:
395 		gic_set_polarity(irq, GIC_POL_POS);
396 		gic_set_trigger(irq, GIC_TRIG_EDGE);
397 		gic_set_dual_edge(irq, GIC_TRIG_DUAL_DISABLE);
398 		is_edge = true;
399 		break;
400 	case IRQ_TYPE_EDGE_BOTH:
401 		/* polarity is irrelevant in this case */
402 		gic_set_trigger(irq, GIC_TRIG_EDGE);
403 		gic_set_dual_edge(irq, GIC_TRIG_DUAL_ENABLE);
404 		is_edge = true;
405 		break;
406 	case IRQ_TYPE_LEVEL_LOW:
407 		gic_set_polarity(irq, GIC_POL_NEG);
408 		gic_set_trigger(irq, GIC_TRIG_LEVEL);
409 		gic_set_dual_edge(irq, GIC_TRIG_DUAL_DISABLE);
410 		is_edge = false;
411 		break;
412 	case IRQ_TYPE_LEVEL_HIGH:
413 	default:
414 		gic_set_polarity(irq, GIC_POL_POS);
415 		gic_set_trigger(irq, GIC_TRIG_LEVEL);
416 		gic_set_dual_edge(irq, GIC_TRIG_DUAL_DISABLE);
417 		is_edge = false;
418 		break;
419 	}
420 
421 	if (is_edge)
422 		irq_set_chip_handler_name_locked(d, &gic_edge_irq_controller,
423 						 handle_edge_irq, NULL);
424 	else
425 		irq_set_chip_handler_name_locked(d, &gic_level_irq_controller,
426 						 handle_level_irq, NULL);
427 	spin_unlock_irqrestore(&gic_lock, flags);
428 
429 	return 0;
430 }
431 
432 #ifdef CONFIG_SMP
433 static int gic_set_affinity(struct irq_data *d, const struct cpumask *cpumask,
434 			    bool force)
435 {
436 	unsigned int irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
437 	cpumask_t	tmp = CPU_MASK_NONE;
438 	unsigned long	flags;
439 	int		i;
440 
441 	cpumask_and(&tmp, cpumask, cpu_online_mask);
442 	if (cpumask_empty(&tmp))
443 		return -EINVAL;
444 
445 	/* Assumption : cpumask refers to a single CPU */
446 	spin_lock_irqsave(&gic_lock, flags);
447 
448 	/* Re-route this IRQ */
449 	gic_map_to_vpe(irq, mips_cm_vp_id(cpumask_first(&tmp)));
450 
451 	/* Update the pcpu_masks */
452 	for (i = 0; i < NR_CPUS; i++)
453 		clear_bit(irq, pcpu_masks[i].pcpu_mask);
454 	set_bit(irq, pcpu_masks[cpumask_first(&tmp)].pcpu_mask);
455 
456 	cpumask_copy(irq_data_get_affinity_mask(d), cpumask);
457 	spin_unlock_irqrestore(&gic_lock, flags);
458 
459 	return IRQ_SET_MASK_OK_NOCOPY;
460 }
461 #endif
462 
463 static struct irq_chip gic_level_irq_controller = {
464 	.name			=	"MIPS GIC",
465 	.irq_mask		=	gic_mask_irq,
466 	.irq_unmask		=	gic_unmask_irq,
467 	.irq_set_type		=	gic_set_type,
468 #ifdef CONFIG_SMP
469 	.irq_set_affinity	=	gic_set_affinity,
470 #endif
471 };
472 
473 static struct irq_chip gic_edge_irq_controller = {
474 	.name			=	"MIPS GIC",
475 	.irq_ack		=	gic_ack_irq,
476 	.irq_mask		=	gic_mask_irq,
477 	.irq_unmask		=	gic_unmask_irq,
478 	.irq_set_type		=	gic_set_type,
479 #ifdef CONFIG_SMP
480 	.irq_set_affinity	=	gic_set_affinity,
481 #endif
482 };
483 
484 static void gic_handle_local_int(bool chained)
485 {
486 	unsigned long pending, masked;
487 	unsigned int intr, virq;
488 
489 	pending = gic_read32(GIC_REG(VPE_LOCAL, GIC_VPE_PEND));
490 	masked = gic_read32(GIC_REG(VPE_LOCAL, GIC_VPE_MASK));
491 
492 	bitmap_and(&pending, &pending, &masked, GIC_NUM_LOCAL_INTRS);
493 
494 	intr = find_first_bit(&pending, GIC_NUM_LOCAL_INTRS);
495 	while (intr != GIC_NUM_LOCAL_INTRS) {
496 		virq = irq_linear_revmap(gic_irq_domain,
497 					 GIC_LOCAL_TO_HWIRQ(intr));
498 		if (chained)
499 			generic_handle_irq(virq);
500 		else
501 			do_IRQ(virq);
502 
503 		/* go to next pending bit */
504 		bitmap_clear(&pending, intr, 1);
505 		intr = find_first_bit(&pending, GIC_NUM_LOCAL_INTRS);
506 	}
507 }
508 
509 static void gic_mask_local_irq(struct irq_data *d)
510 {
511 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
512 
513 	gic_write32(GIC_REG(VPE_LOCAL, GIC_VPE_RMASK), 1 << intr);
514 }
515 
516 static void gic_unmask_local_irq(struct irq_data *d)
517 {
518 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
519 
520 	gic_write32(GIC_REG(VPE_LOCAL, GIC_VPE_SMASK), 1 << intr);
521 }
522 
523 static struct irq_chip gic_local_irq_controller = {
524 	.name			=	"MIPS GIC Local",
525 	.irq_mask		=	gic_mask_local_irq,
526 	.irq_unmask		=	gic_unmask_local_irq,
527 };
528 
529 static void gic_mask_local_irq_all_vpes(struct irq_data *d)
530 {
531 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
532 	int i;
533 	unsigned long flags;
534 
535 	spin_lock_irqsave(&gic_lock, flags);
536 	for (i = 0; i < gic_vpes; i++) {
537 		gic_write(GIC_REG(VPE_LOCAL, GIC_VPE_OTHER_ADDR), i);
538 		gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_RMASK), 1 << intr);
539 	}
540 	spin_unlock_irqrestore(&gic_lock, flags);
541 }
542 
543 static void gic_unmask_local_irq_all_vpes(struct irq_data *d)
544 {
545 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
546 	int i;
547 	unsigned long flags;
548 
549 	spin_lock_irqsave(&gic_lock, flags);
550 	for (i = 0; i < gic_vpes; i++) {
551 		gic_write(GIC_REG(VPE_LOCAL, GIC_VPE_OTHER_ADDR), i);
552 		gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_SMASK), 1 << intr);
553 	}
554 	spin_unlock_irqrestore(&gic_lock, flags);
555 }
556 
557 static struct irq_chip gic_all_vpes_local_irq_controller = {
558 	.name			=	"MIPS GIC Local",
559 	.irq_mask		=	gic_mask_local_irq_all_vpes,
560 	.irq_unmask		=	gic_unmask_local_irq_all_vpes,
561 };
562 
563 static void __gic_irq_dispatch(void)
564 {
565 	gic_handle_local_int(false);
566 	gic_handle_shared_int(false);
567 }
568 
569 static void gic_irq_dispatch(struct irq_desc *desc)
570 {
571 	gic_handle_local_int(true);
572 	gic_handle_shared_int(true);
573 }
574 
575 #ifdef CONFIG_MIPS_GIC_IPI
576 static int gic_resched_int_base;
577 static int gic_call_int_base;
578 
579 unsigned int plat_ipi_resched_int_xlate(unsigned int cpu)
580 {
581 	return gic_resched_int_base + cpu;
582 }
583 
584 unsigned int plat_ipi_call_int_xlate(unsigned int cpu)
585 {
586 	return gic_call_int_base + cpu;
587 }
588 
589 static irqreturn_t ipi_resched_interrupt(int irq, void *dev_id)
590 {
591 	scheduler_ipi();
592 
593 	return IRQ_HANDLED;
594 }
595 
596 static irqreturn_t ipi_call_interrupt(int irq, void *dev_id)
597 {
598 	generic_smp_call_function_interrupt();
599 
600 	return IRQ_HANDLED;
601 }
602 
603 static struct irqaction irq_resched = {
604 	.handler	= ipi_resched_interrupt,
605 	.flags		= IRQF_PERCPU,
606 	.name		= "IPI resched"
607 };
608 
609 static struct irqaction irq_call = {
610 	.handler	= ipi_call_interrupt,
611 	.flags		= IRQF_PERCPU,
612 	.name		= "IPI call"
613 };
614 
615 static __init void gic_ipi_init_one(unsigned int intr, int cpu,
616 				    struct irqaction *action)
617 {
618 	int virq = irq_create_mapping(gic_irq_domain,
619 				      GIC_SHARED_TO_HWIRQ(intr));
620 	int i;
621 
622 	gic_map_to_vpe(intr, mips_cm_vp_id(cpu));
623 	for (i = 0; i < NR_CPUS; i++)
624 		clear_bit(intr, pcpu_masks[i].pcpu_mask);
625 	set_bit(intr, pcpu_masks[cpu].pcpu_mask);
626 
627 	irq_set_irq_type(virq, IRQ_TYPE_EDGE_RISING);
628 
629 	irq_set_handler(virq, handle_percpu_irq);
630 	setup_irq(virq, action);
631 }
632 
633 static __init void gic_ipi_init(void)
634 {
635 	int i;
636 
637 	/* Use last 2 * NR_CPUS interrupts as IPIs */
638 	gic_resched_int_base = gic_shared_intrs - nr_cpu_ids;
639 	gic_call_int_base = gic_resched_int_base - nr_cpu_ids;
640 
641 	for (i = 0; i < nr_cpu_ids; i++) {
642 		gic_ipi_init_one(gic_call_int_base + i, i, &irq_call);
643 		gic_ipi_init_one(gic_resched_int_base + i, i, &irq_resched);
644 	}
645 }
646 #else
647 static inline void gic_ipi_init(void)
648 {
649 }
650 #endif
651 
652 static void __init gic_basic_init(void)
653 {
654 	unsigned int i;
655 
656 	board_bind_eic_interrupt = &gic_bind_eic_interrupt;
657 
658 	/* Setup defaults */
659 	for (i = 0; i < gic_shared_intrs; i++) {
660 		gic_set_polarity(i, GIC_POL_POS);
661 		gic_set_trigger(i, GIC_TRIG_LEVEL);
662 		gic_reset_mask(i);
663 	}
664 
665 	for (i = 0; i < gic_vpes; i++) {
666 		unsigned int j;
667 
668 		gic_write(GIC_REG(VPE_LOCAL, GIC_VPE_OTHER_ADDR), i);
669 		for (j = 0; j < GIC_NUM_LOCAL_INTRS; j++) {
670 			if (!gic_local_irq_is_routable(j))
671 				continue;
672 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_RMASK), 1 << j);
673 		}
674 	}
675 }
676 
677 static int gic_local_irq_domain_map(struct irq_domain *d, unsigned int virq,
678 				    irq_hw_number_t hw)
679 {
680 	int intr = GIC_HWIRQ_TO_LOCAL(hw);
681 	int ret = 0;
682 	int i;
683 	unsigned long flags;
684 
685 	if (!gic_local_irq_is_routable(intr))
686 		return -EPERM;
687 
688 	/*
689 	 * HACK: These are all really percpu interrupts, but the rest
690 	 * of the MIPS kernel code does not use the percpu IRQ API for
691 	 * the CP0 timer and performance counter interrupts.
692 	 */
693 	switch (intr) {
694 	case GIC_LOCAL_INT_TIMER:
695 	case GIC_LOCAL_INT_PERFCTR:
696 	case GIC_LOCAL_INT_FDC:
697 		irq_set_chip_and_handler(virq,
698 					 &gic_all_vpes_local_irq_controller,
699 					 handle_percpu_irq);
700 		break;
701 	default:
702 		irq_set_chip_and_handler(virq,
703 					 &gic_local_irq_controller,
704 					 handle_percpu_devid_irq);
705 		irq_set_percpu_devid(virq);
706 		break;
707 	}
708 
709 	spin_lock_irqsave(&gic_lock, flags);
710 	for (i = 0; i < gic_vpes; i++) {
711 		u32 val = GIC_MAP_TO_PIN_MSK | gic_cpu_pin;
712 
713 		gic_write(GIC_REG(VPE_LOCAL, GIC_VPE_OTHER_ADDR), i);
714 
715 		switch (intr) {
716 		case GIC_LOCAL_INT_WD:
717 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_WD_MAP), val);
718 			break;
719 		case GIC_LOCAL_INT_COMPARE:
720 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_COMPARE_MAP),
721 				    val);
722 			break;
723 		case GIC_LOCAL_INT_TIMER:
724 			/* CONFIG_MIPS_CMP workaround (see __gic_init) */
725 			val = GIC_MAP_TO_PIN_MSK | timer_cpu_pin;
726 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_TIMER_MAP),
727 				    val);
728 			break;
729 		case GIC_LOCAL_INT_PERFCTR:
730 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_PERFCTR_MAP),
731 				    val);
732 			break;
733 		case GIC_LOCAL_INT_SWINT0:
734 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_SWINT0_MAP),
735 				    val);
736 			break;
737 		case GIC_LOCAL_INT_SWINT1:
738 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_SWINT1_MAP),
739 				    val);
740 			break;
741 		case GIC_LOCAL_INT_FDC:
742 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_FDC_MAP), val);
743 			break;
744 		default:
745 			pr_err("Invalid local IRQ %d\n", intr);
746 			ret = -EINVAL;
747 			break;
748 		}
749 	}
750 	spin_unlock_irqrestore(&gic_lock, flags);
751 
752 	return ret;
753 }
754 
755 static int gic_shared_irq_domain_map(struct irq_domain *d, unsigned int virq,
756 				     irq_hw_number_t hw)
757 {
758 	int intr = GIC_HWIRQ_TO_SHARED(hw);
759 	unsigned long flags;
760 
761 	irq_set_chip_and_handler(virq, &gic_level_irq_controller,
762 				 handle_level_irq);
763 
764 	spin_lock_irqsave(&gic_lock, flags);
765 	gic_map_to_pin(intr, gic_cpu_pin);
766 	/* Map to VPE 0 by default */
767 	gic_map_to_vpe(intr, 0);
768 	set_bit(intr, pcpu_masks[0].pcpu_mask);
769 	spin_unlock_irqrestore(&gic_lock, flags);
770 
771 	return 0;
772 }
773 
774 static int gic_irq_domain_map(struct irq_domain *d, unsigned int virq,
775 			      irq_hw_number_t hw)
776 {
777 	if (GIC_HWIRQ_TO_LOCAL(hw) < GIC_NUM_LOCAL_INTRS)
778 		return gic_local_irq_domain_map(d, virq, hw);
779 	return gic_shared_irq_domain_map(d, virq, hw);
780 }
781 
782 static int gic_irq_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
783 				const u32 *intspec, unsigned int intsize,
784 				irq_hw_number_t *out_hwirq,
785 				unsigned int *out_type)
786 {
787 	if (intsize != 3)
788 		return -EINVAL;
789 
790 	if (intspec[0] == GIC_SHARED)
791 		*out_hwirq = GIC_SHARED_TO_HWIRQ(intspec[1]);
792 	else if (intspec[0] == GIC_LOCAL)
793 		*out_hwirq = GIC_LOCAL_TO_HWIRQ(intspec[1]);
794 	else
795 		return -EINVAL;
796 	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
797 
798 	return 0;
799 }
800 
801 static const struct irq_domain_ops gic_irq_domain_ops = {
802 	.map = gic_irq_domain_map,
803 	.xlate = gic_irq_domain_xlate,
804 };
805 
806 static void __init __gic_init(unsigned long gic_base_addr,
807 			      unsigned long gic_addrspace_size,
808 			      unsigned int cpu_vec, unsigned int irqbase,
809 			      struct device_node *node)
810 {
811 	unsigned int gicconfig;
812 
813 	__gic_base_addr = gic_base_addr;
814 
815 	gic_base = ioremap_nocache(gic_base_addr, gic_addrspace_size);
816 
817 	gicconfig = gic_read(GIC_REG(SHARED, GIC_SH_CONFIG));
818 	gic_shared_intrs = (gicconfig & GIC_SH_CONFIG_NUMINTRS_MSK) >>
819 		   GIC_SH_CONFIG_NUMINTRS_SHF;
820 	gic_shared_intrs = ((gic_shared_intrs + 1) * 8);
821 
822 	gic_vpes = (gicconfig & GIC_SH_CONFIG_NUMVPES_MSK) >>
823 		  GIC_SH_CONFIG_NUMVPES_SHF;
824 	gic_vpes = gic_vpes + 1;
825 
826 	if (cpu_has_veic) {
827 		/* Always use vector 1 in EIC mode */
828 		gic_cpu_pin = 0;
829 		timer_cpu_pin = gic_cpu_pin;
830 		set_vi_handler(gic_cpu_pin + GIC_PIN_TO_VEC_OFFSET,
831 			       __gic_irq_dispatch);
832 	} else {
833 		gic_cpu_pin = cpu_vec - GIC_CPU_PIN_OFFSET;
834 		irq_set_chained_handler(MIPS_CPU_IRQ_BASE + cpu_vec,
835 					gic_irq_dispatch);
836 		/*
837 		 * With the CMP implementation of SMP (deprecated), other CPUs
838 		 * are started by the bootloader and put into a timer based
839 		 * waiting poll loop. We must not re-route those CPU's local
840 		 * timer interrupts as the wait instruction will never finish,
841 		 * so just handle whatever CPU interrupt it is routed to by
842 		 * default.
843 		 *
844 		 * This workaround should be removed when CMP support is
845 		 * dropped.
846 		 */
847 		if (IS_ENABLED(CONFIG_MIPS_CMP) &&
848 		    gic_local_irq_is_routable(GIC_LOCAL_INT_TIMER)) {
849 			timer_cpu_pin = gic_read32(GIC_REG(VPE_LOCAL,
850 							 GIC_VPE_TIMER_MAP)) &
851 					GIC_MAP_MSK;
852 			irq_set_chained_handler(MIPS_CPU_IRQ_BASE +
853 						GIC_CPU_PIN_OFFSET +
854 						timer_cpu_pin,
855 						gic_irq_dispatch);
856 		} else {
857 			timer_cpu_pin = gic_cpu_pin;
858 		}
859 	}
860 
861 	gic_irq_domain = irq_domain_add_simple(node, GIC_NUM_LOCAL_INTRS +
862 					       gic_shared_intrs, irqbase,
863 					       &gic_irq_domain_ops, NULL);
864 	if (!gic_irq_domain)
865 		panic("Failed to add GIC IRQ domain");
866 
867 	gic_basic_init();
868 
869 	gic_ipi_init();
870 }
871 
872 void __init gic_init(unsigned long gic_base_addr,
873 		     unsigned long gic_addrspace_size,
874 		     unsigned int cpu_vec, unsigned int irqbase)
875 {
876 	__gic_init(gic_base_addr, gic_addrspace_size, cpu_vec, irqbase, NULL);
877 }
878 
879 static int __init gic_of_init(struct device_node *node,
880 			      struct device_node *parent)
881 {
882 	struct resource res;
883 	unsigned int cpu_vec, i = 0, reserved = 0;
884 	phys_addr_t gic_base;
885 	size_t gic_len;
886 
887 	/* Find the first available CPU vector. */
888 	while (!of_property_read_u32_index(node, "mti,reserved-cpu-vectors",
889 					   i++, &cpu_vec))
890 		reserved |= BIT(cpu_vec);
891 	for (cpu_vec = 2; cpu_vec < 8; cpu_vec++) {
892 		if (!(reserved & BIT(cpu_vec)))
893 			break;
894 	}
895 	if (cpu_vec == 8) {
896 		pr_err("No CPU vectors available for GIC\n");
897 		return -ENODEV;
898 	}
899 
900 	if (of_address_to_resource(node, 0, &res)) {
901 		/*
902 		 * Probe the CM for the GIC base address if not specified
903 		 * in the device-tree.
904 		 */
905 		if (mips_cm_present()) {
906 			gic_base = read_gcr_gic_base() &
907 				~CM_GCR_GIC_BASE_GICEN_MSK;
908 			gic_len = 0x20000;
909 		} else {
910 			pr_err("Failed to get GIC memory range\n");
911 			return -ENODEV;
912 		}
913 	} else {
914 		gic_base = res.start;
915 		gic_len = resource_size(&res);
916 	}
917 
918 	if (mips_cm_present())
919 		write_gcr_gic_base(gic_base | CM_GCR_GIC_BASE_GICEN_MSK);
920 	gic_present = true;
921 
922 	__gic_init(gic_base, gic_len, cpu_vec, 0, node);
923 
924 	return 0;
925 }
926 IRQCHIP_DECLARE(mips_gic, "mti,gic", gic_of_init);
927