xref: /linux/drivers/irqchip/irq-mips-gic.c (revision f3a8b6645dc2e60d11f20c1c23afd964ff4e55ae)
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 struct gic_irq_spec {
33 	enum {
34 		GIC_DEVICE,
35 		GIC_IPI
36 	} type;
37 
38 	union {
39 		struct cpumask *ipimask;
40 		unsigned int hwirq;
41 	};
42 };
43 
44 static unsigned long __gic_base_addr;
45 
46 static void __iomem *gic_base;
47 static struct gic_pcpu_mask pcpu_masks[NR_CPUS];
48 static DEFINE_SPINLOCK(gic_lock);
49 static struct irq_domain *gic_irq_domain;
50 static struct irq_domain *gic_dev_domain;
51 static struct irq_domain *gic_ipi_domain;
52 static int gic_shared_intrs;
53 static int gic_vpes;
54 static unsigned int gic_cpu_pin;
55 static unsigned int timer_cpu_pin;
56 static struct irq_chip gic_level_irq_controller, gic_edge_irq_controller;
57 DECLARE_BITMAP(ipi_resrv, GIC_MAX_INTRS);
58 
59 static void __gic_irq_dispatch(void);
60 
61 static inline u32 gic_read32(unsigned int reg)
62 {
63 	return __raw_readl(gic_base + reg);
64 }
65 
66 static inline u64 gic_read64(unsigned int reg)
67 {
68 	return __raw_readq(gic_base + reg);
69 }
70 
71 static inline unsigned long gic_read(unsigned int reg)
72 {
73 	if (!mips_cm_is64)
74 		return gic_read32(reg);
75 	else
76 		return gic_read64(reg);
77 }
78 
79 static inline void gic_write32(unsigned int reg, u32 val)
80 {
81 	return __raw_writel(val, gic_base + reg);
82 }
83 
84 static inline void gic_write64(unsigned int reg, u64 val)
85 {
86 	return __raw_writeq(val, gic_base + reg);
87 }
88 
89 static inline void gic_write(unsigned int reg, unsigned long val)
90 {
91 	if (!mips_cm_is64)
92 		return gic_write32(reg, (u32)val);
93 	else
94 		return gic_write64(reg, (u64)val);
95 }
96 
97 static inline void gic_update_bits(unsigned int reg, unsigned long mask,
98 				   unsigned long val)
99 {
100 	unsigned long regval;
101 
102 	regval = gic_read(reg);
103 	regval &= ~mask;
104 	regval |= val;
105 	gic_write(reg, regval);
106 }
107 
108 static inline void gic_reset_mask(unsigned int intr)
109 {
110 	gic_write(GIC_REG(SHARED, GIC_SH_RMASK) + GIC_INTR_OFS(intr),
111 		  1ul << GIC_INTR_BIT(intr));
112 }
113 
114 static inline void gic_set_mask(unsigned int intr)
115 {
116 	gic_write(GIC_REG(SHARED, GIC_SH_SMASK) + GIC_INTR_OFS(intr),
117 		  1ul << GIC_INTR_BIT(intr));
118 }
119 
120 static inline void gic_set_polarity(unsigned int intr, unsigned int pol)
121 {
122 	gic_update_bits(GIC_REG(SHARED, GIC_SH_SET_POLARITY) +
123 			GIC_INTR_OFS(intr), 1ul << GIC_INTR_BIT(intr),
124 			(unsigned long)pol << GIC_INTR_BIT(intr));
125 }
126 
127 static inline void gic_set_trigger(unsigned int intr, unsigned int trig)
128 {
129 	gic_update_bits(GIC_REG(SHARED, GIC_SH_SET_TRIGGER) +
130 			GIC_INTR_OFS(intr), 1ul << GIC_INTR_BIT(intr),
131 			(unsigned long)trig << GIC_INTR_BIT(intr));
132 }
133 
134 static inline void gic_set_dual_edge(unsigned int intr, unsigned int dual)
135 {
136 	gic_update_bits(GIC_REG(SHARED, GIC_SH_SET_DUAL) + GIC_INTR_OFS(intr),
137 			1ul << GIC_INTR_BIT(intr),
138 			(unsigned long)dual << GIC_INTR_BIT(intr));
139 }
140 
141 static inline void gic_map_to_pin(unsigned int intr, unsigned int pin)
142 {
143 	gic_write32(GIC_REG(SHARED, GIC_SH_INTR_MAP_TO_PIN_BASE) +
144 		    GIC_SH_MAP_TO_PIN(intr), GIC_MAP_TO_PIN_MSK | pin);
145 }
146 
147 static inline void gic_map_to_vpe(unsigned int intr, unsigned int vpe)
148 {
149 	gic_write(GIC_REG(SHARED, GIC_SH_INTR_MAP_TO_VPE_BASE) +
150 		  GIC_SH_MAP_TO_VPE_REG_OFF(intr, vpe),
151 		  GIC_SH_MAP_TO_VPE_REG_BIT(vpe));
152 }
153 
154 #ifdef CONFIG_CLKSRC_MIPS_GIC
155 cycle_t gic_read_count(void)
156 {
157 	unsigned int hi, hi2, lo;
158 
159 	if (mips_cm_is64)
160 		return (cycle_t)gic_read(GIC_REG(SHARED, GIC_SH_COUNTER));
161 
162 	do {
163 		hi = gic_read32(GIC_REG(SHARED, GIC_SH_COUNTER_63_32));
164 		lo = gic_read32(GIC_REG(SHARED, GIC_SH_COUNTER_31_00));
165 		hi2 = gic_read32(GIC_REG(SHARED, GIC_SH_COUNTER_63_32));
166 	} while (hi2 != hi);
167 
168 	return (((cycle_t) hi) << 32) + lo;
169 }
170 
171 unsigned int gic_get_count_width(void)
172 {
173 	unsigned int bits, config;
174 
175 	config = gic_read(GIC_REG(SHARED, GIC_SH_CONFIG));
176 	bits = 32 + 4 * ((config & GIC_SH_CONFIG_COUNTBITS_MSK) >>
177 			 GIC_SH_CONFIG_COUNTBITS_SHF);
178 
179 	return bits;
180 }
181 
182 void gic_write_compare(cycle_t cnt)
183 {
184 	if (mips_cm_is64) {
185 		gic_write(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE), cnt);
186 	} else {
187 		gic_write32(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_HI),
188 					(int)(cnt >> 32));
189 		gic_write32(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_LO),
190 					(int)(cnt & 0xffffffff));
191 	}
192 }
193 
194 void gic_write_cpu_compare(cycle_t cnt, int cpu)
195 {
196 	unsigned long flags;
197 
198 	local_irq_save(flags);
199 
200 	gic_write(GIC_REG(VPE_LOCAL, GIC_VPE_OTHER_ADDR), mips_cm_vp_id(cpu));
201 
202 	if (mips_cm_is64) {
203 		gic_write(GIC_REG(VPE_OTHER, GIC_VPE_COMPARE), cnt);
204 	} else {
205 		gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_COMPARE_HI),
206 					(int)(cnt >> 32));
207 		gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_COMPARE_LO),
208 					(int)(cnt & 0xffffffff));
209 	}
210 
211 	local_irq_restore(flags);
212 }
213 
214 cycle_t gic_read_compare(void)
215 {
216 	unsigned int hi, lo;
217 
218 	if (mips_cm_is64)
219 		return (cycle_t)gic_read(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE));
220 
221 	hi = gic_read32(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_HI));
222 	lo = gic_read32(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_LO));
223 
224 	return (((cycle_t) hi) << 32) + lo;
225 }
226 
227 void gic_start_count(void)
228 {
229 	u32 gicconfig;
230 
231 	/* Start the counter */
232 	gicconfig = gic_read(GIC_REG(SHARED, GIC_SH_CONFIG));
233 	gicconfig &= ~(1 << GIC_SH_CONFIG_COUNTSTOP_SHF);
234 	gic_write(GIC_REG(SHARED, GIC_SH_CONFIG), gicconfig);
235 }
236 
237 void gic_stop_count(void)
238 {
239 	u32 gicconfig;
240 
241 	/* Stop the counter */
242 	gicconfig = gic_read(GIC_REG(SHARED, GIC_SH_CONFIG));
243 	gicconfig |= 1 << GIC_SH_CONFIG_COUNTSTOP_SHF;
244 	gic_write(GIC_REG(SHARED, GIC_SH_CONFIG), gicconfig);
245 }
246 
247 #endif
248 
249 unsigned gic_read_local_vp_id(void)
250 {
251 	unsigned long ident;
252 
253 	ident = gic_read(GIC_REG(VPE_LOCAL, GIC_VP_IDENT));
254 	return ident & GIC_VP_IDENT_VCNUM_MSK;
255 }
256 
257 static bool gic_local_irq_is_routable(int intr)
258 {
259 	u32 vpe_ctl;
260 
261 	/* All local interrupts are routable in EIC mode. */
262 	if (cpu_has_veic)
263 		return true;
264 
265 	vpe_ctl = gic_read32(GIC_REG(VPE_LOCAL, GIC_VPE_CTL));
266 	switch (intr) {
267 	case GIC_LOCAL_INT_TIMER:
268 		return vpe_ctl & GIC_VPE_CTL_TIMER_RTBL_MSK;
269 	case GIC_LOCAL_INT_PERFCTR:
270 		return vpe_ctl & GIC_VPE_CTL_PERFCNT_RTBL_MSK;
271 	case GIC_LOCAL_INT_FDC:
272 		return vpe_ctl & GIC_VPE_CTL_FDC_RTBL_MSK;
273 	case GIC_LOCAL_INT_SWINT0:
274 	case GIC_LOCAL_INT_SWINT1:
275 		return vpe_ctl & GIC_VPE_CTL_SWINT_RTBL_MSK;
276 	default:
277 		return true;
278 	}
279 }
280 
281 static void gic_bind_eic_interrupt(int irq, int set)
282 {
283 	/* Convert irq vector # to hw int # */
284 	irq -= GIC_PIN_TO_VEC_OFFSET;
285 
286 	/* Set irq to use shadow set */
287 	gic_write(GIC_REG(VPE_LOCAL, GIC_VPE_EIC_SHADOW_SET_BASE) +
288 		  GIC_VPE_EIC_SS(irq), set);
289 }
290 
291 static void gic_send_ipi(struct irq_data *d, unsigned int cpu)
292 {
293 	irq_hw_number_t hwirq = GIC_HWIRQ_TO_SHARED(irqd_to_hwirq(d));
294 
295 	gic_write(GIC_REG(SHARED, GIC_SH_WEDGE), GIC_SH_WEDGE_SET(hwirq));
296 }
297 
298 int gic_get_c0_compare_int(void)
299 {
300 	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_TIMER))
301 		return MIPS_CPU_IRQ_BASE + cp0_compare_irq;
302 	return irq_create_mapping(gic_irq_domain,
303 				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_TIMER));
304 }
305 
306 int gic_get_c0_perfcount_int(void)
307 {
308 	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_PERFCTR)) {
309 		/* Is the performance counter shared with the timer? */
310 		if (cp0_perfcount_irq < 0)
311 			return -1;
312 		return MIPS_CPU_IRQ_BASE + cp0_perfcount_irq;
313 	}
314 	return irq_create_mapping(gic_irq_domain,
315 				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_PERFCTR));
316 }
317 
318 int gic_get_c0_fdc_int(void)
319 {
320 	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_FDC)) {
321 		/* Is the FDC IRQ even present? */
322 		if (cp0_fdc_irq < 0)
323 			return -1;
324 		return MIPS_CPU_IRQ_BASE + cp0_fdc_irq;
325 	}
326 
327 	return irq_create_mapping(gic_irq_domain,
328 				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_FDC));
329 }
330 
331 int gic_get_usm_range(struct resource *gic_usm_res)
332 {
333 	if (!gic_present)
334 		return -1;
335 
336 	gic_usm_res->start = __gic_base_addr + USM_VISIBLE_SECTION_OFS;
337 	gic_usm_res->end = gic_usm_res->start + (USM_VISIBLE_SECTION_SIZE - 1);
338 
339 	return 0;
340 }
341 
342 static void gic_handle_shared_int(bool chained)
343 {
344 	unsigned int i, intr, virq, gic_reg_step = mips_cm_is64 ? 8 : 4;
345 	unsigned long *pcpu_mask;
346 	unsigned long pending_reg, intrmask_reg;
347 	DECLARE_BITMAP(pending, GIC_MAX_INTRS);
348 	DECLARE_BITMAP(intrmask, GIC_MAX_INTRS);
349 
350 	/* Get per-cpu bitmaps */
351 	pcpu_mask = pcpu_masks[smp_processor_id()].pcpu_mask;
352 
353 	pending_reg = GIC_REG(SHARED, GIC_SH_PEND);
354 	intrmask_reg = GIC_REG(SHARED, GIC_SH_MASK);
355 
356 	for (i = 0; i < BITS_TO_LONGS(gic_shared_intrs); i++) {
357 		pending[i] = gic_read(pending_reg);
358 		intrmask[i] = gic_read(intrmask_reg);
359 		pending_reg += gic_reg_step;
360 		intrmask_reg += gic_reg_step;
361 
362 		if (!IS_ENABLED(CONFIG_64BIT) || mips_cm_is64)
363 			continue;
364 
365 		pending[i] |= (u64)gic_read(pending_reg) << 32;
366 		intrmask[i] |= (u64)gic_read(intrmask_reg) << 32;
367 		pending_reg += gic_reg_step;
368 		intrmask_reg += gic_reg_step;
369 	}
370 
371 	bitmap_and(pending, pending, intrmask, gic_shared_intrs);
372 	bitmap_and(pending, pending, pcpu_mask, gic_shared_intrs);
373 
374 	for_each_set_bit(intr, pending, gic_shared_intrs) {
375 		virq = irq_linear_revmap(gic_irq_domain,
376 					 GIC_SHARED_TO_HWIRQ(intr));
377 		if (chained)
378 			generic_handle_irq(virq);
379 		else
380 			do_IRQ(virq);
381 	}
382 }
383 
384 static void gic_mask_irq(struct irq_data *d)
385 {
386 	gic_reset_mask(GIC_HWIRQ_TO_SHARED(d->hwirq));
387 }
388 
389 static void gic_unmask_irq(struct irq_data *d)
390 {
391 	gic_set_mask(GIC_HWIRQ_TO_SHARED(d->hwirq));
392 }
393 
394 static void gic_ack_irq(struct irq_data *d)
395 {
396 	unsigned int irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
397 
398 	gic_write(GIC_REG(SHARED, GIC_SH_WEDGE), GIC_SH_WEDGE_CLR(irq));
399 }
400 
401 static int gic_set_type(struct irq_data *d, unsigned int type)
402 {
403 	unsigned int irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
404 	unsigned long flags;
405 	bool is_edge;
406 
407 	spin_lock_irqsave(&gic_lock, flags);
408 	switch (type & IRQ_TYPE_SENSE_MASK) {
409 	case IRQ_TYPE_EDGE_FALLING:
410 		gic_set_polarity(irq, GIC_POL_NEG);
411 		gic_set_trigger(irq, GIC_TRIG_EDGE);
412 		gic_set_dual_edge(irq, GIC_TRIG_DUAL_DISABLE);
413 		is_edge = true;
414 		break;
415 	case IRQ_TYPE_EDGE_RISING:
416 		gic_set_polarity(irq, GIC_POL_POS);
417 		gic_set_trigger(irq, GIC_TRIG_EDGE);
418 		gic_set_dual_edge(irq, GIC_TRIG_DUAL_DISABLE);
419 		is_edge = true;
420 		break;
421 	case IRQ_TYPE_EDGE_BOTH:
422 		/* polarity is irrelevant in this case */
423 		gic_set_trigger(irq, GIC_TRIG_EDGE);
424 		gic_set_dual_edge(irq, GIC_TRIG_DUAL_ENABLE);
425 		is_edge = true;
426 		break;
427 	case IRQ_TYPE_LEVEL_LOW:
428 		gic_set_polarity(irq, GIC_POL_NEG);
429 		gic_set_trigger(irq, GIC_TRIG_LEVEL);
430 		gic_set_dual_edge(irq, GIC_TRIG_DUAL_DISABLE);
431 		is_edge = false;
432 		break;
433 	case IRQ_TYPE_LEVEL_HIGH:
434 	default:
435 		gic_set_polarity(irq, GIC_POL_POS);
436 		gic_set_trigger(irq, GIC_TRIG_LEVEL);
437 		gic_set_dual_edge(irq, GIC_TRIG_DUAL_DISABLE);
438 		is_edge = false;
439 		break;
440 	}
441 
442 	if (is_edge)
443 		irq_set_chip_handler_name_locked(d, &gic_edge_irq_controller,
444 						 handle_edge_irq, NULL);
445 	else
446 		irq_set_chip_handler_name_locked(d, &gic_level_irq_controller,
447 						 handle_level_irq, NULL);
448 	spin_unlock_irqrestore(&gic_lock, flags);
449 
450 	return 0;
451 }
452 
453 #ifdef CONFIG_SMP
454 static int gic_set_affinity(struct irq_data *d, const struct cpumask *cpumask,
455 			    bool force)
456 {
457 	unsigned int irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
458 	cpumask_t	tmp = CPU_MASK_NONE;
459 	unsigned long	flags;
460 	int		i;
461 
462 	cpumask_and(&tmp, cpumask, cpu_online_mask);
463 	if (cpumask_empty(&tmp))
464 		return -EINVAL;
465 
466 	/* Assumption : cpumask refers to a single CPU */
467 	spin_lock_irqsave(&gic_lock, flags);
468 
469 	/* Re-route this IRQ */
470 	gic_map_to_vpe(irq, mips_cm_vp_id(cpumask_first(&tmp)));
471 
472 	/* Update the pcpu_masks */
473 	for (i = 0; i < min(gic_vpes, NR_CPUS); i++)
474 		clear_bit(irq, pcpu_masks[i].pcpu_mask);
475 	set_bit(irq, pcpu_masks[cpumask_first(&tmp)].pcpu_mask);
476 
477 	cpumask_copy(irq_data_get_affinity_mask(d), cpumask);
478 	spin_unlock_irqrestore(&gic_lock, flags);
479 
480 	return IRQ_SET_MASK_OK_NOCOPY;
481 }
482 #endif
483 
484 static struct irq_chip gic_level_irq_controller = {
485 	.name			=	"MIPS GIC",
486 	.irq_mask		=	gic_mask_irq,
487 	.irq_unmask		=	gic_unmask_irq,
488 	.irq_set_type		=	gic_set_type,
489 #ifdef CONFIG_SMP
490 	.irq_set_affinity	=	gic_set_affinity,
491 #endif
492 };
493 
494 static struct irq_chip gic_edge_irq_controller = {
495 	.name			=	"MIPS GIC",
496 	.irq_ack		=	gic_ack_irq,
497 	.irq_mask		=	gic_mask_irq,
498 	.irq_unmask		=	gic_unmask_irq,
499 	.irq_set_type		=	gic_set_type,
500 #ifdef CONFIG_SMP
501 	.irq_set_affinity	=	gic_set_affinity,
502 #endif
503 	.ipi_send_single	=	gic_send_ipi,
504 };
505 
506 static void gic_handle_local_int(bool chained)
507 {
508 	unsigned long pending, masked;
509 	unsigned int intr, virq;
510 
511 	pending = gic_read32(GIC_REG(VPE_LOCAL, GIC_VPE_PEND));
512 	masked = gic_read32(GIC_REG(VPE_LOCAL, GIC_VPE_MASK));
513 
514 	bitmap_and(&pending, &pending, &masked, GIC_NUM_LOCAL_INTRS);
515 
516 	for_each_set_bit(intr, &pending, GIC_NUM_LOCAL_INTRS) {
517 		virq = irq_linear_revmap(gic_irq_domain,
518 					 GIC_LOCAL_TO_HWIRQ(intr));
519 		if (chained)
520 			generic_handle_irq(virq);
521 		else
522 			do_IRQ(virq);
523 	}
524 }
525 
526 static void gic_mask_local_irq(struct irq_data *d)
527 {
528 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
529 
530 	gic_write32(GIC_REG(VPE_LOCAL, GIC_VPE_RMASK), 1 << intr);
531 }
532 
533 static void gic_unmask_local_irq(struct irq_data *d)
534 {
535 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
536 
537 	gic_write32(GIC_REG(VPE_LOCAL, GIC_VPE_SMASK), 1 << intr);
538 }
539 
540 static struct irq_chip gic_local_irq_controller = {
541 	.name			=	"MIPS GIC Local",
542 	.irq_mask		=	gic_mask_local_irq,
543 	.irq_unmask		=	gic_unmask_local_irq,
544 };
545 
546 static void gic_mask_local_irq_all_vpes(struct irq_data *d)
547 {
548 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
549 	int i;
550 	unsigned long flags;
551 
552 	spin_lock_irqsave(&gic_lock, flags);
553 	for (i = 0; i < gic_vpes; i++) {
554 		gic_write(GIC_REG(VPE_LOCAL, GIC_VPE_OTHER_ADDR),
555 			  mips_cm_vp_id(i));
556 		gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_RMASK), 1 << intr);
557 	}
558 	spin_unlock_irqrestore(&gic_lock, flags);
559 }
560 
561 static void gic_unmask_local_irq_all_vpes(struct irq_data *d)
562 {
563 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
564 	int i;
565 	unsigned long flags;
566 
567 	spin_lock_irqsave(&gic_lock, flags);
568 	for (i = 0; i < gic_vpes; i++) {
569 		gic_write(GIC_REG(VPE_LOCAL, GIC_VPE_OTHER_ADDR),
570 			  mips_cm_vp_id(i));
571 		gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_SMASK), 1 << intr);
572 	}
573 	spin_unlock_irqrestore(&gic_lock, flags);
574 }
575 
576 static struct irq_chip gic_all_vpes_local_irq_controller = {
577 	.name			=	"MIPS GIC Local",
578 	.irq_mask		=	gic_mask_local_irq_all_vpes,
579 	.irq_unmask		=	gic_unmask_local_irq_all_vpes,
580 };
581 
582 static void __gic_irq_dispatch(void)
583 {
584 	gic_handle_local_int(false);
585 	gic_handle_shared_int(false);
586 }
587 
588 static void gic_irq_dispatch(struct irq_desc *desc)
589 {
590 	gic_handle_local_int(true);
591 	gic_handle_shared_int(true);
592 }
593 
594 static void __init gic_basic_init(void)
595 {
596 	unsigned int i;
597 
598 	board_bind_eic_interrupt = &gic_bind_eic_interrupt;
599 
600 	/* Setup defaults */
601 	for (i = 0; i < gic_shared_intrs; i++) {
602 		gic_set_polarity(i, GIC_POL_POS);
603 		gic_set_trigger(i, GIC_TRIG_LEVEL);
604 		gic_reset_mask(i);
605 	}
606 
607 	for (i = 0; i < gic_vpes; i++) {
608 		unsigned int j;
609 
610 		gic_write(GIC_REG(VPE_LOCAL, GIC_VPE_OTHER_ADDR),
611 			  mips_cm_vp_id(i));
612 		for (j = 0; j < GIC_NUM_LOCAL_INTRS; j++) {
613 			if (!gic_local_irq_is_routable(j))
614 				continue;
615 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_RMASK), 1 << j);
616 		}
617 	}
618 }
619 
620 static int gic_local_irq_domain_map(struct irq_domain *d, unsigned int virq,
621 				    irq_hw_number_t hw)
622 {
623 	int intr = GIC_HWIRQ_TO_LOCAL(hw);
624 	int ret = 0;
625 	int i;
626 	unsigned long flags;
627 
628 	if (!gic_local_irq_is_routable(intr))
629 		return -EPERM;
630 
631 	spin_lock_irqsave(&gic_lock, flags);
632 	for (i = 0; i < gic_vpes; i++) {
633 		u32 val = GIC_MAP_TO_PIN_MSK | gic_cpu_pin;
634 
635 		gic_write(GIC_REG(VPE_LOCAL, GIC_VPE_OTHER_ADDR),
636 			  mips_cm_vp_id(i));
637 
638 		switch (intr) {
639 		case GIC_LOCAL_INT_WD:
640 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_WD_MAP), val);
641 			break;
642 		case GIC_LOCAL_INT_COMPARE:
643 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_COMPARE_MAP),
644 				    val);
645 			break;
646 		case GIC_LOCAL_INT_TIMER:
647 			/* CONFIG_MIPS_CMP workaround (see __gic_init) */
648 			val = GIC_MAP_TO_PIN_MSK | timer_cpu_pin;
649 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_TIMER_MAP),
650 				    val);
651 			break;
652 		case GIC_LOCAL_INT_PERFCTR:
653 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_PERFCTR_MAP),
654 				    val);
655 			break;
656 		case GIC_LOCAL_INT_SWINT0:
657 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_SWINT0_MAP),
658 				    val);
659 			break;
660 		case GIC_LOCAL_INT_SWINT1:
661 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_SWINT1_MAP),
662 				    val);
663 			break;
664 		case GIC_LOCAL_INT_FDC:
665 			gic_write32(GIC_REG(VPE_OTHER, GIC_VPE_FDC_MAP), val);
666 			break;
667 		default:
668 			pr_err("Invalid local IRQ %d\n", intr);
669 			ret = -EINVAL;
670 			break;
671 		}
672 	}
673 	spin_unlock_irqrestore(&gic_lock, flags);
674 
675 	return ret;
676 }
677 
678 static int gic_shared_irq_domain_map(struct irq_domain *d, unsigned int virq,
679 				     irq_hw_number_t hw, unsigned int vpe)
680 {
681 	int intr = GIC_HWIRQ_TO_SHARED(hw);
682 	unsigned long flags;
683 	int i;
684 
685 	spin_lock_irqsave(&gic_lock, flags);
686 	gic_map_to_pin(intr, gic_cpu_pin);
687 	gic_map_to_vpe(intr, mips_cm_vp_id(vpe));
688 	for (i = 0; i < min(gic_vpes, NR_CPUS); i++)
689 		clear_bit(intr, pcpu_masks[i].pcpu_mask);
690 	set_bit(intr, pcpu_masks[vpe].pcpu_mask);
691 	spin_unlock_irqrestore(&gic_lock, flags);
692 
693 	return 0;
694 }
695 
696 static int gic_setup_dev_chip(struct irq_domain *d, unsigned int virq,
697 			      unsigned int hwirq)
698 {
699 	struct irq_chip *chip;
700 	int err;
701 
702 	if (hwirq >= GIC_SHARED_HWIRQ_BASE) {
703 		err = irq_domain_set_hwirq_and_chip(d, virq, hwirq,
704 						    &gic_level_irq_controller,
705 						    NULL);
706 	} else {
707 		switch (GIC_HWIRQ_TO_LOCAL(hwirq)) {
708 		case GIC_LOCAL_INT_TIMER:
709 		case GIC_LOCAL_INT_PERFCTR:
710 		case GIC_LOCAL_INT_FDC:
711 			/*
712 			 * HACK: These are all really percpu interrupts, but
713 			 * the rest of the MIPS kernel code does not use the
714 			 * percpu IRQ API for them.
715 			 */
716 			chip = &gic_all_vpes_local_irq_controller;
717 			irq_set_handler(virq, handle_percpu_irq);
718 			break;
719 
720 		default:
721 			chip = &gic_local_irq_controller;
722 			irq_set_handler(virq, handle_percpu_devid_irq);
723 			irq_set_percpu_devid(virq);
724 			break;
725 		}
726 
727 		err = irq_domain_set_hwirq_and_chip(d, virq, hwirq,
728 						    chip, NULL);
729 	}
730 
731 	return err;
732 }
733 
734 static int gic_irq_domain_alloc(struct irq_domain *d, unsigned int virq,
735 				unsigned int nr_irqs, void *arg)
736 {
737 	struct gic_irq_spec *spec = arg;
738 	irq_hw_number_t hwirq, base_hwirq;
739 	int cpu, ret, i;
740 
741 	if (spec->type == GIC_DEVICE) {
742 		/* verify that shared irqs don't conflict with an IPI irq */
743 		if ((spec->hwirq >= GIC_SHARED_HWIRQ_BASE) &&
744 		    test_bit(GIC_HWIRQ_TO_SHARED(spec->hwirq), ipi_resrv))
745 			return -EBUSY;
746 
747 		return gic_setup_dev_chip(d, virq, spec->hwirq);
748 	} else {
749 		base_hwirq = find_first_bit(ipi_resrv, gic_shared_intrs);
750 		if (base_hwirq == gic_shared_intrs) {
751 			return -ENOMEM;
752 		}
753 
754 		/* check that we have enough space */
755 		for (i = base_hwirq; i < nr_irqs; i++) {
756 			if (!test_bit(i, ipi_resrv))
757 				return -EBUSY;
758 		}
759 		bitmap_clear(ipi_resrv, base_hwirq, nr_irqs);
760 
761 		/* map the hwirq for each cpu consecutively */
762 		i = 0;
763 		for_each_cpu(cpu, spec->ipimask) {
764 			hwirq = GIC_SHARED_TO_HWIRQ(base_hwirq + i);
765 
766 			ret = irq_domain_set_hwirq_and_chip(d, virq + i, hwirq,
767 							    &gic_level_irq_controller,
768 							    NULL);
769 			if (ret)
770 				goto error;
771 
772 			irq_set_handler(virq + i, handle_level_irq);
773 
774 			ret = gic_shared_irq_domain_map(d, virq + i, hwirq, cpu);
775 			if (ret)
776 				goto error;
777 
778 			i++;
779 		}
780 
781 		/*
782 		 * tell the parent about the base hwirq we allocated so it can
783 		 * set its own domain data
784 		 */
785 		spec->hwirq = base_hwirq;
786 	}
787 
788 	return 0;
789 error:
790 	bitmap_set(ipi_resrv, base_hwirq, nr_irqs);
791 	return ret;
792 }
793 
794 void gic_irq_domain_free(struct irq_domain *d, unsigned int virq,
795 			 unsigned int nr_irqs)
796 {
797 	irq_hw_number_t base_hwirq;
798 	struct irq_data *data;
799 
800 	data = irq_get_irq_data(virq);
801 	if (!data)
802 		return;
803 
804 	base_hwirq = GIC_HWIRQ_TO_SHARED(irqd_to_hwirq(data));
805 	bitmap_set(ipi_resrv, base_hwirq, nr_irqs);
806 }
807 
808 int gic_irq_domain_match(struct irq_domain *d, struct device_node *node,
809 			 enum irq_domain_bus_token bus_token)
810 {
811 	/* this domain should'nt be accessed directly */
812 	return 0;
813 }
814 
815 static const struct irq_domain_ops gic_irq_domain_ops = {
816 	.alloc = gic_irq_domain_alloc,
817 	.free = gic_irq_domain_free,
818 	.match = gic_irq_domain_match,
819 };
820 
821 static int gic_dev_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
822 				const u32 *intspec, unsigned int intsize,
823 				irq_hw_number_t *out_hwirq,
824 				unsigned int *out_type)
825 {
826 	if (intsize != 3)
827 		return -EINVAL;
828 
829 	if (intspec[0] == GIC_SHARED)
830 		*out_hwirq = GIC_SHARED_TO_HWIRQ(intspec[1]);
831 	else if (intspec[0] == GIC_LOCAL)
832 		*out_hwirq = GIC_LOCAL_TO_HWIRQ(intspec[1]);
833 	else
834 		return -EINVAL;
835 	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
836 
837 	return 0;
838 }
839 
840 static int gic_dev_domain_alloc(struct irq_domain *d, unsigned int virq,
841 				unsigned int nr_irqs, void *arg)
842 {
843 	struct irq_fwspec *fwspec = arg;
844 	struct gic_irq_spec spec = {
845 		.type = GIC_DEVICE,
846 	};
847 	int i, ret;
848 
849 	if (fwspec->param[0] == GIC_SHARED)
850 		spec.hwirq = GIC_SHARED_TO_HWIRQ(fwspec->param[1]);
851 	else
852 		spec.hwirq = GIC_LOCAL_TO_HWIRQ(fwspec->param[1]);
853 
854 	ret = irq_domain_alloc_irqs_parent(d, virq, nr_irqs, &spec);
855 	if (ret)
856 		return ret;
857 
858 	for (i = 0; i < nr_irqs; i++) {
859 		ret = gic_setup_dev_chip(d, virq + i, spec.hwirq + i);
860 		if (ret)
861 			goto error;
862 	}
863 
864 	return 0;
865 
866 error:
867 	irq_domain_free_irqs_parent(d, virq, nr_irqs);
868 	return ret;
869 }
870 
871 void gic_dev_domain_free(struct irq_domain *d, unsigned int virq,
872 			 unsigned int nr_irqs)
873 {
874 	/* no real allocation is done for dev irqs, so no need to free anything */
875 	return;
876 }
877 
878 static void gic_dev_domain_activate(struct irq_domain *domain,
879 				    struct irq_data *d)
880 {
881 	if (GIC_HWIRQ_TO_LOCAL(d->hwirq) < GIC_NUM_LOCAL_INTRS)
882 		gic_local_irq_domain_map(domain, d->irq, d->hwirq);
883 	else
884 		gic_shared_irq_domain_map(domain, d->irq, d->hwirq, 0);
885 }
886 
887 static struct irq_domain_ops gic_dev_domain_ops = {
888 	.xlate = gic_dev_domain_xlate,
889 	.alloc = gic_dev_domain_alloc,
890 	.free = gic_dev_domain_free,
891 	.activate = gic_dev_domain_activate,
892 };
893 
894 static int gic_ipi_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
895 				const u32 *intspec, unsigned int intsize,
896 				irq_hw_number_t *out_hwirq,
897 				unsigned int *out_type)
898 {
899 	/*
900 	 * There's nothing to translate here. hwirq is dynamically allocated and
901 	 * the irq type is always edge triggered.
902 	 * */
903 	*out_hwirq = 0;
904 	*out_type = IRQ_TYPE_EDGE_RISING;
905 
906 	return 0;
907 }
908 
909 static int gic_ipi_domain_alloc(struct irq_domain *d, unsigned int virq,
910 				unsigned int nr_irqs, void *arg)
911 {
912 	struct cpumask *ipimask = arg;
913 	struct gic_irq_spec spec = {
914 		.type = GIC_IPI,
915 		.ipimask = ipimask
916 	};
917 	int ret, i;
918 
919 	ret = irq_domain_alloc_irqs_parent(d, virq, nr_irqs, &spec);
920 	if (ret)
921 		return ret;
922 
923 	/* the parent should have set spec.hwirq to the base_hwirq it allocated */
924 	for (i = 0; i < nr_irqs; i++) {
925 		ret = irq_domain_set_hwirq_and_chip(d, virq + i,
926 						    GIC_SHARED_TO_HWIRQ(spec.hwirq + i),
927 						    &gic_edge_irq_controller,
928 						    NULL);
929 		if (ret)
930 			goto error;
931 
932 		ret = irq_set_irq_type(virq + i, IRQ_TYPE_EDGE_RISING);
933 		if (ret)
934 			goto error;
935 	}
936 
937 	return 0;
938 error:
939 	irq_domain_free_irqs_parent(d, virq, nr_irqs);
940 	return ret;
941 }
942 
943 void gic_ipi_domain_free(struct irq_domain *d, unsigned int virq,
944 			 unsigned int nr_irqs)
945 {
946 	irq_domain_free_irqs_parent(d, virq, nr_irqs);
947 }
948 
949 int gic_ipi_domain_match(struct irq_domain *d, struct device_node *node,
950 			 enum irq_domain_bus_token bus_token)
951 {
952 	bool is_ipi;
953 
954 	switch (bus_token) {
955 	case DOMAIN_BUS_IPI:
956 		is_ipi = d->bus_token == bus_token;
957 		return (!node || to_of_node(d->fwnode) == node) && is_ipi;
958 		break;
959 	default:
960 		return 0;
961 	}
962 }
963 
964 static struct irq_domain_ops gic_ipi_domain_ops = {
965 	.xlate = gic_ipi_domain_xlate,
966 	.alloc = gic_ipi_domain_alloc,
967 	.free = gic_ipi_domain_free,
968 	.match = gic_ipi_domain_match,
969 };
970 
971 static void __init __gic_init(unsigned long gic_base_addr,
972 			      unsigned long gic_addrspace_size,
973 			      unsigned int cpu_vec, unsigned int irqbase,
974 			      struct device_node *node)
975 {
976 	unsigned int gicconfig, cpu;
977 	unsigned int v[2];
978 
979 	__gic_base_addr = gic_base_addr;
980 
981 	gic_base = ioremap_nocache(gic_base_addr, gic_addrspace_size);
982 
983 	gicconfig = gic_read(GIC_REG(SHARED, GIC_SH_CONFIG));
984 	gic_shared_intrs = (gicconfig & GIC_SH_CONFIG_NUMINTRS_MSK) >>
985 		   GIC_SH_CONFIG_NUMINTRS_SHF;
986 	gic_shared_intrs = ((gic_shared_intrs + 1) * 8);
987 
988 	gic_vpes = (gicconfig & GIC_SH_CONFIG_NUMVPES_MSK) >>
989 		  GIC_SH_CONFIG_NUMVPES_SHF;
990 	gic_vpes = gic_vpes + 1;
991 
992 	if (cpu_has_veic) {
993 		/* Set EIC mode for all VPEs */
994 		for_each_present_cpu(cpu) {
995 			gic_write(GIC_REG(VPE_LOCAL, GIC_VPE_OTHER_ADDR),
996 				  mips_cm_vp_id(cpu));
997 			gic_write(GIC_REG(VPE_OTHER, GIC_VPE_CTL),
998 				  GIC_VPE_CTL_EIC_MODE_MSK);
999 		}
1000 
1001 		/* Always use vector 1 in EIC mode */
1002 		gic_cpu_pin = 0;
1003 		timer_cpu_pin = gic_cpu_pin;
1004 		set_vi_handler(gic_cpu_pin + GIC_PIN_TO_VEC_OFFSET,
1005 			       __gic_irq_dispatch);
1006 	} else {
1007 		gic_cpu_pin = cpu_vec - GIC_CPU_PIN_OFFSET;
1008 		irq_set_chained_handler(MIPS_CPU_IRQ_BASE + cpu_vec,
1009 					gic_irq_dispatch);
1010 		/*
1011 		 * With the CMP implementation of SMP (deprecated), other CPUs
1012 		 * are started by the bootloader and put into a timer based
1013 		 * waiting poll loop. We must not re-route those CPU's local
1014 		 * timer interrupts as the wait instruction will never finish,
1015 		 * so just handle whatever CPU interrupt it is routed to by
1016 		 * default.
1017 		 *
1018 		 * This workaround should be removed when CMP support is
1019 		 * dropped.
1020 		 */
1021 		if (IS_ENABLED(CONFIG_MIPS_CMP) &&
1022 		    gic_local_irq_is_routable(GIC_LOCAL_INT_TIMER)) {
1023 			timer_cpu_pin = gic_read32(GIC_REG(VPE_LOCAL,
1024 							 GIC_VPE_TIMER_MAP)) &
1025 					GIC_MAP_MSK;
1026 			irq_set_chained_handler(MIPS_CPU_IRQ_BASE +
1027 						GIC_CPU_PIN_OFFSET +
1028 						timer_cpu_pin,
1029 						gic_irq_dispatch);
1030 		} else {
1031 			timer_cpu_pin = gic_cpu_pin;
1032 		}
1033 	}
1034 
1035 	gic_irq_domain = irq_domain_add_simple(node, GIC_NUM_LOCAL_INTRS +
1036 					       gic_shared_intrs, irqbase,
1037 					       &gic_irq_domain_ops, NULL);
1038 	if (!gic_irq_domain)
1039 		panic("Failed to add GIC IRQ domain");
1040 	gic_irq_domain->name = "mips-gic-irq";
1041 
1042 	gic_dev_domain = irq_domain_add_hierarchy(gic_irq_domain, 0,
1043 						  GIC_NUM_LOCAL_INTRS + gic_shared_intrs,
1044 						  node, &gic_dev_domain_ops, NULL);
1045 	if (!gic_dev_domain)
1046 		panic("Failed to add GIC DEV domain");
1047 	gic_dev_domain->name = "mips-gic-dev";
1048 
1049 	gic_ipi_domain = irq_domain_add_hierarchy(gic_irq_domain,
1050 						  IRQ_DOMAIN_FLAG_IPI_PER_CPU,
1051 						  GIC_NUM_LOCAL_INTRS + gic_shared_intrs,
1052 						  node, &gic_ipi_domain_ops, NULL);
1053 	if (!gic_ipi_domain)
1054 		panic("Failed to add GIC IPI domain");
1055 
1056 	gic_ipi_domain->name = "mips-gic-ipi";
1057 	gic_ipi_domain->bus_token = DOMAIN_BUS_IPI;
1058 
1059 	if (node &&
1060 	    !of_property_read_u32_array(node, "mti,reserved-ipi-vectors", v, 2)) {
1061 		bitmap_set(ipi_resrv, v[0], v[1]);
1062 	} else {
1063 		/* Make the last 2 * gic_vpes available for IPIs */
1064 		bitmap_set(ipi_resrv,
1065 			   gic_shared_intrs - 2 * gic_vpes,
1066 			   2 * gic_vpes);
1067 	}
1068 
1069 	gic_basic_init();
1070 }
1071 
1072 void __init gic_init(unsigned long gic_base_addr,
1073 		     unsigned long gic_addrspace_size,
1074 		     unsigned int cpu_vec, unsigned int irqbase)
1075 {
1076 	__gic_init(gic_base_addr, gic_addrspace_size, cpu_vec, irqbase, NULL);
1077 }
1078 
1079 static int __init gic_of_init(struct device_node *node,
1080 			      struct device_node *parent)
1081 {
1082 	struct resource res;
1083 	unsigned int cpu_vec, i = 0, reserved = 0;
1084 	phys_addr_t gic_base;
1085 	size_t gic_len;
1086 
1087 	/* Find the first available CPU vector. */
1088 	while (!of_property_read_u32_index(node, "mti,reserved-cpu-vectors",
1089 					   i++, &cpu_vec))
1090 		reserved |= BIT(cpu_vec);
1091 	for (cpu_vec = 2; cpu_vec < 8; cpu_vec++) {
1092 		if (!(reserved & BIT(cpu_vec)))
1093 			break;
1094 	}
1095 	if (cpu_vec == 8) {
1096 		pr_err("No CPU vectors available for GIC\n");
1097 		return -ENODEV;
1098 	}
1099 
1100 	if (of_address_to_resource(node, 0, &res)) {
1101 		/*
1102 		 * Probe the CM for the GIC base address if not specified
1103 		 * in the device-tree.
1104 		 */
1105 		if (mips_cm_present()) {
1106 			gic_base = read_gcr_gic_base() &
1107 				~CM_GCR_GIC_BASE_GICEN_MSK;
1108 			gic_len = 0x20000;
1109 		} else {
1110 			pr_err("Failed to get GIC memory range\n");
1111 			return -ENODEV;
1112 		}
1113 	} else {
1114 		gic_base = res.start;
1115 		gic_len = resource_size(&res);
1116 	}
1117 
1118 	if (mips_cm_present())
1119 		write_gcr_gic_base(gic_base | CM_GCR_GIC_BASE_GICEN_MSK);
1120 	gic_present = true;
1121 
1122 	__gic_init(gic_base, gic_len, cpu_vec, 0, node);
1123 
1124 	return 0;
1125 }
1126 IRQCHIP_DECLARE(mips_gic, "mti,gic", gic_of_init);
1127