xref: /linux/drivers/irqchip/irq-armada-370-xp.c (revision 06a130e42a5bfc84795464bff023bff4c16f58c5)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Marvell Armada 370 and Armada XP SoC IRQ handling
4  *
5  * Copyright (C) 2012 Marvell
6  *
7  * Lior Amsalem <alior@marvell.com>
8  * Gregory CLEMENT <gregory.clement@free-electrons.com>
9  * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
10  * Ben Dooks <ben.dooks@codethink.co.uk>
11  */
12 
13 #include <linux/bitfield.h>
14 #include <linux/bits.h>
15 #include <linux/err.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/irq.h>
20 #include <linux/interrupt.h>
21 #include <linux/irqchip.h>
22 #include <linux/irqchip/chained_irq.h>
23 #include <linux/cpu.h>
24 #include <linux/io.h>
25 #include <linux/of_address.h>
26 #include <linux/of_irq.h>
27 #include <linux/of_pci.h>
28 #include <linux/irqdomain.h>
29 #include <linux/slab.h>
30 #include <linux/syscore_ops.h>
31 #include <linux/msi.h>
32 #include <linux/types.h>
33 #include <asm/mach/arch.h>
34 #include <asm/exception.h>
35 #include <asm/smp_plat.h>
36 #include <asm/mach/irq.h>
37 
38 /*
39  * Overall diagram of the Armada XP interrupt controller:
40  *
41  *    To CPU 0                 To CPU 1
42  *
43  *       /\                       /\
44  *       ||                       ||
45  * +---------------+     +---------------+
46  * |               |	 |               |
47  * |    per-CPU    |	 |    per-CPU    |
48  * |  mask/unmask  |	 |  mask/unmask  |
49  * |     CPU0      |	 |     CPU1      |
50  * |               |	 |               |
51  * +---------------+	 +---------------+
52  *        /\                       /\
53  *        ||                       ||
54  *        \\_______________________//
55  *                     ||
56  *            +-------------------+
57  *            |                   |
58  *            | Global interrupt  |
59  *            |    mask/unmask    |
60  *            |                   |
61  *            +-------------------+
62  *                     /\
63  *                     ||
64  *               interrupt from
65  *                   device
66  *
67  * The "global interrupt mask/unmask" is modified using the
68  * MPIC_INT_SET_ENABLE and MPIC_INT_CLEAR_ENABLE
69  * registers, which are relative to "mpic->base".
70  *
71  * The "per-CPU mask/unmask" is modified using the MPIC_INT_SET_MASK
72  * and MPIC_INT_CLEAR_MASK registers, which are relative to
73  * "mpic->per_cpu". This base address points to a special address,
74  * which automatically accesses the registers of the current CPU.
75  *
76  * The per-CPU mask/unmask can also be adjusted using the global
77  * per-interrupt MPIC_INT_SOURCE_CTL register, which we use to
78  * configure interrupt affinity.
79  *
80  * Due to this model, all interrupts need to be mask/unmasked at two
81  * different levels: at the global level and at the per-CPU level.
82  *
83  * This driver takes the following approach to deal with this:
84  *
85  *  - For global interrupts:
86  *
87  *    At ->map() time, a global interrupt is unmasked at the per-CPU
88  *    mask/unmask level. It is therefore unmasked at this level for
89  *    the current CPU, running the ->map() code. This allows to have
90  *    the interrupt unmasked at this level in non-SMP
91  *    configurations. In SMP configurations, the ->set_affinity()
92  *    callback is called, which using the MPIC_INT_SOURCE_CTL()
93  *    readjusts the per-CPU mask/unmask for the interrupt.
94  *
95  *    The ->mask() and ->unmask() operations only mask/unmask the
96  *    interrupt at the "global" level.
97  *
98  *    So, a global interrupt is enabled at the per-CPU level as soon
99  *    as it is mapped. At run time, the masking/unmasking takes place
100  *    at the global level.
101  *
102  *  - For per-CPU interrupts
103  *
104  *    At ->map() time, a per-CPU interrupt is unmasked at the global
105  *    mask/unmask level.
106  *
107  *    The ->mask() and ->unmask() operations mask/unmask the interrupt
108  *    at the per-CPU level.
109  *
110  *    So, a per-CPU interrupt is enabled at the global level as soon
111  *    as it is mapped. At run time, the masking/unmasking takes place
112  *    at the per-CPU level.
113  */
114 
115 /* Registers relative to mpic->base */
116 #define MPIC_INT_CONTROL			0x00
117 #define MPIC_INT_CONTROL_NUMINT_MASK		GENMASK(12, 2)
118 #define MPIC_SW_TRIG_INT			0x04
119 #define MPIC_INT_SET_ENABLE			0x30
120 #define MPIC_INT_CLEAR_ENABLE			0x34
121 #define MPIC_INT_SOURCE_CTL(hwirq)		(0x100 + (hwirq) * 4)
122 #define MPIC_INT_SOURCE_CPU_MASK		GENMASK(3, 0)
123 #define MPIC_INT_IRQ_FIQ_MASK(cpuid)		((BIT(0) | BIT(8)) << (cpuid))
124 
125 /* Registers relative to mpic->per_cpu */
126 #define MPIC_IN_DRBEL_CAUSE			0x08
127 #define MPIC_IN_DRBEL_MASK			0x0c
128 #define MPIC_PPI_CAUSE				0x10
129 #define MPIC_CPU_INTACK				0x44
130 #define MPIC_CPU_INTACK_IID_MASK		GENMASK(9, 0)
131 #define MPIC_INT_SET_MASK			0x48
132 #define MPIC_INT_CLEAR_MASK			0x4C
133 #define MPIC_INT_FABRIC_MASK			0x54
134 #define MPIC_INT_CAUSE_PERF(cpu)		BIT(cpu)
135 
136 #define MPIC_PER_CPU_IRQS_NR			29
137 
138 /* IPI and MSI interrupt definitions for IPI platforms */
139 #define IPI_DOORBELL_NR				8
140 #define IPI_DOORBELL_MASK			GENMASK(7, 0)
141 #define PCI_MSI_DOORBELL_START			16
142 #define PCI_MSI_DOORBELL_NR			16
143 #define PCI_MSI_DOORBELL_MASK			GENMASK(31, 16)
144 
145 /* MSI interrupt definitions for non-IPI platforms */
146 #define PCI_MSI_FULL_DOORBELL_START		0
147 #define PCI_MSI_FULL_DOORBELL_NR		32
148 #define PCI_MSI_FULL_DOORBELL_MASK		GENMASK(31, 0)
149 #define PCI_MSI_FULL_DOORBELL_SRC0_MASK		GENMASK(15, 0)
150 #define PCI_MSI_FULL_DOORBELL_SRC1_MASK		GENMASK(31, 16)
151 
152 /**
153  * struct mpic - MPIC private data structure
154  * @base:		MPIC registers base address
155  * @per_cpu:		per-CPU registers base address
156  * @parent_irq:		parent IRQ if MPIC is not top-level interrupt controller
157  * @domain:		MPIC main interrupt domain
158  * @ipi_domain:		IPI domain
159  * @msi_domain:		MSI domain
160  * @msi_inner_domain:	MSI inner domain
161  * @msi_used:		bitmap of used MSI numbers
162  * @msi_lock:		mutex serializing access to @msi_used
163  * @msi_doorbell_addr:	physical address of MSI doorbell register
164  * @msi_doorbell_mask:	mask of available doorbell bits for MSIs (either PCI_MSI_DOORBELL_MASK or
165  *			PCI_MSI_FULL_DOORBELL_MASK)
166  * @msi_doorbell_start:	first set bit in @msi_doorbell_mask
167  * @msi_doorbell_size:	number of set bits in @msi_doorbell_mask
168  * @doorbell_mask:	doorbell mask of MSIs and IPIs, stored on suspend, restored on resume
169  */
170 struct mpic {
171 	void __iomem *base;
172 	void __iomem *per_cpu;
173 	int parent_irq;
174 	struct irq_domain *domain;
175 #ifdef CONFIG_SMP
176 	struct irq_domain *ipi_domain;
177 #endif
178 #ifdef CONFIG_PCI_MSI
179 	struct irq_domain *msi_domain;
180 	struct irq_domain *msi_inner_domain;
181 	DECLARE_BITMAP(msi_used, PCI_MSI_FULL_DOORBELL_NR);
182 	struct mutex msi_lock;
183 	phys_addr_t msi_doorbell_addr;
184 	u32 msi_doorbell_mask;
185 	unsigned int msi_doorbell_start, msi_doorbell_size;
186 #endif
187 	u32 doorbell_mask;
188 };
189 
190 static struct mpic *mpic_data __ro_after_init;
191 
192 static inline bool mpic_is_ipi_available(struct mpic *mpic)
193 {
194 	/*
195 	 * We distinguish IPI availability in the IC by the IC not having a
196 	 * parent irq defined. If a parent irq is defined, there is a parent
197 	 * interrupt controller (e.g. GIC) that takes care of inter-processor
198 	 * interrupts.
199 	 */
200 	return mpic->parent_irq <= 0;
201 }
202 
203 static inline bool mpic_is_percpu_irq(irq_hw_number_t hwirq)
204 {
205 	return hwirq < MPIC_PER_CPU_IRQS_NR;
206 }
207 
208 /*
209  * In SMP mode:
210  * For shared global interrupts, mask/unmask global enable bit
211  * For CPU interrupts, mask/unmask the calling CPU's bit
212  */
213 static void mpic_irq_mask(struct irq_data *d)
214 {
215 	struct mpic *mpic = irq_data_get_irq_chip_data(d);
216 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
217 
218 	if (!mpic_is_percpu_irq(hwirq))
219 		writel(hwirq, mpic->base + MPIC_INT_CLEAR_ENABLE);
220 	else
221 		writel(hwirq, mpic->per_cpu + MPIC_INT_SET_MASK);
222 }
223 
224 static void mpic_irq_unmask(struct irq_data *d)
225 {
226 	struct mpic *mpic = irq_data_get_irq_chip_data(d);
227 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
228 
229 	if (!mpic_is_percpu_irq(hwirq))
230 		writel(hwirq, mpic->base + MPIC_INT_SET_ENABLE);
231 	else
232 		writel(hwirq, mpic->per_cpu + MPIC_INT_CLEAR_MASK);
233 }
234 
235 #ifdef CONFIG_PCI_MSI
236 
237 static struct irq_chip mpic_msi_irq_chip = {
238 	.name		= "MPIC MSI",
239 	.irq_mask	= pci_msi_mask_irq,
240 	.irq_unmask	= pci_msi_unmask_irq,
241 };
242 
243 static struct msi_domain_info mpic_msi_domain_info = {
244 	.flags	= (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
245 		   MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX),
246 	.chip	= &mpic_msi_irq_chip,
247 };
248 
249 static void mpic_compose_msi_msg(struct irq_data *d, struct msi_msg *msg)
250 {
251 	unsigned int cpu = cpumask_first(irq_data_get_effective_affinity_mask(d));
252 	struct mpic *mpic = irq_data_get_irq_chip_data(d);
253 
254 	msg->address_lo = lower_32_bits(mpic->msi_doorbell_addr);
255 	msg->address_hi = upper_32_bits(mpic->msi_doorbell_addr);
256 	msg->data = BIT(cpu + 8) | (d->hwirq + mpic->msi_doorbell_start);
257 }
258 
259 static int mpic_msi_set_affinity(struct irq_data *d, const struct cpumask *mask, bool force)
260 {
261 	unsigned int cpu;
262 
263 	if (!force)
264 		cpu = cpumask_any_and(mask, cpu_online_mask);
265 	else
266 		cpu = cpumask_first(mask);
267 
268 	if (cpu >= nr_cpu_ids)
269 		return -EINVAL;
270 
271 	irq_data_update_effective_affinity(d, cpumask_of(cpu));
272 
273 	return IRQ_SET_MASK_OK;
274 }
275 
276 static struct irq_chip mpic_msi_bottom_irq_chip = {
277 	.name			= "MPIC MSI",
278 	.irq_compose_msi_msg	= mpic_compose_msi_msg,
279 	.irq_set_affinity	= mpic_msi_set_affinity,
280 };
281 
282 static int mpic_msi_alloc(struct irq_domain *domain, unsigned int virq, unsigned int nr_irqs,
283 			  void *args)
284 {
285 	struct mpic *mpic = domain->host_data;
286 	int hwirq;
287 
288 	mutex_lock(&mpic->msi_lock);
289 	hwirq = bitmap_find_free_region(mpic->msi_used, mpic->msi_doorbell_size,
290 					order_base_2(nr_irqs));
291 	mutex_unlock(&mpic->msi_lock);
292 
293 	if (hwirq < 0)
294 		return -ENOSPC;
295 
296 	for (unsigned int i = 0; i < nr_irqs; i++) {
297 		irq_domain_set_info(domain, virq + i, hwirq + i,
298 				    &mpic_msi_bottom_irq_chip,
299 				    domain->host_data, handle_simple_irq,
300 				    NULL, NULL);
301 	}
302 
303 	return 0;
304 }
305 
306 static void mpic_msi_free(struct irq_domain *domain, unsigned int virq, unsigned int nr_irqs)
307 {
308 	struct irq_data *d = irq_domain_get_irq_data(domain, virq);
309 	struct mpic *mpic = domain->host_data;
310 
311 	mutex_lock(&mpic->msi_lock);
312 	bitmap_release_region(mpic->msi_used, d->hwirq, order_base_2(nr_irqs));
313 	mutex_unlock(&mpic->msi_lock);
314 }
315 
316 static const struct irq_domain_ops mpic_msi_domain_ops = {
317 	.alloc	= mpic_msi_alloc,
318 	.free	= mpic_msi_free,
319 };
320 
321 static void mpic_msi_reenable_percpu(struct mpic *mpic)
322 {
323 	u32 reg;
324 
325 	/* Enable MSI doorbell mask and combined cpu local interrupt */
326 	reg = readl(mpic->per_cpu + MPIC_IN_DRBEL_MASK);
327 	reg |= mpic->msi_doorbell_mask;
328 	writel(reg, mpic->per_cpu + MPIC_IN_DRBEL_MASK);
329 
330 	/* Unmask local doorbell interrupt */
331 	writel(1, mpic->per_cpu + MPIC_INT_CLEAR_MASK);
332 }
333 
334 static int __init mpic_msi_init(struct mpic *mpic, struct device_node *node,
335 				phys_addr_t main_int_phys_base)
336 {
337 	mpic->msi_doorbell_addr = main_int_phys_base + MPIC_SW_TRIG_INT;
338 
339 	mutex_init(&mpic->msi_lock);
340 
341 	if (mpic_is_ipi_available(mpic)) {
342 		mpic->msi_doorbell_start = PCI_MSI_DOORBELL_START;
343 		mpic->msi_doorbell_size = PCI_MSI_DOORBELL_NR;
344 		mpic->msi_doorbell_mask = PCI_MSI_DOORBELL_MASK;
345 	} else {
346 		mpic->msi_doorbell_start = PCI_MSI_FULL_DOORBELL_START;
347 		mpic->msi_doorbell_size = PCI_MSI_FULL_DOORBELL_NR;
348 		mpic->msi_doorbell_mask = PCI_MSI_FULL_DOORBELL_MASK;
349 	}
350 
351 	mpic->msi_inner_domain = irq_domain_add_linear(NULL, mpic->msi_doorbell_size,
352 						       &mpic_msi_domain_ops, mpic);
353 	if (!mpic->msi_inner_domain)
354 		return -ENOMEM;
355 
356 	mpic->msi_domain = pci_msi_create_irq_domain(of_node_to_fwnode(node), &mpic_msi_domain_info,
357 						     mpic->msi_inner_domain);
358 	if (!mpic->msi_domain) {
359 		irq_domain_remove(mpic->msi_inner_domain);
360 		return -ENOMEM;
361 	}
362 
363 	mpic_msi_reenable_percpu(mpic);
364 
365 	/* Unmask low 16 MSI irqs on non-IPI platforms */
366 	if (!mpic_is_ipi_available(mpic))
367 		writel(0, mpic->per_cpu + MPIC_INT_CLEAR_MASK);
368 
369 	return 0;
370 }
371 #else
372 static __maybe_unused void mpic_msi_reenable_percpu(struct mpic *mpic) {}
373 
374 static inline int mpic_msi_init(struct mpic *mpic, struct device_node *node,
375 				phys_addr_t main_int_phys_base)
376 {
377 	return 0;
378 }
379 #endif
380 
381 static void mpic_perf_init(struct mpic *mpic)
382 {
383 	u32 cpuid;
384 
385 	/*
386 	 * This Performance Counter Overflow interrupt is specific for
387 	 * Armada 370 and XP. It is not available on Armada 375, 38x and 39x.
388 	 */
389 	if (!of_machine_is_compatible("marvell,armada-370-xp"))
390 		return;
391 
392 	cpuid = cpu_logical_map(smp_processor_id());
393 
394 	/* Enable Performance Counter Overflow interrupts */
395 	writel(MPIC_INT_CAUSE_PERF(cpuid), mpic->per_cpu + MPIC_INT_FABRIC_MASK);
396 }
397 
398 #ifdef CONFIG_SMP
399 static void mpic_ipi_mask(struct irq_data *d)
400 {
401 	struct mpic *mpic = irq_data_get_irq_chip_data(d);
402 	u32 reg;
403 
404 	reg = readl(mpic->per_cpu + MPIC_IN_DRBEL_MASK);
405 	reg &= ~BIT(d->hwirq);
406 	writel(reg, mpic->per_cpu + MPIC_IN_DRBEL_MASK);
407 }
408 
409 static void mpic_ipi_unmask(struct irq_data *d)
410 {
411 	struct mpic *mpic = irq_data_get_irq_chip_data(d);
412 	u32 reg;
413 
414 	reg = readl(mpic->per_cpu + MPIC_IN_DRBEL_MASK);
415 	reg |= BIT(d->hwirq);
416 	writel(reg, mpic->per_cpu + MPIC_IN_DRBEL_MASK);
417 }
418 
419 static void mpic_ipi_send_mask(struct irq_data *d, const struct cpumask *mask)
420 {
421 	struct mpic *mpic = irq_data_get_irq_chip_data(d);
422 	unsigned int cpu;
423 	u32 map = 0;
424 
425 	/* Convert our logical CPU mask into a physical one. */
426 	for_each_cpu(cpu, mask)
427 		map |= BIT(cpu_logical_map(cpu));
428 
429 	/*
430 	 * Ensure that stores to Normal memory are visible to the
431 	 * other CPUs before issuing the IPI.
432 	 */
433 	dsb();
434 
435 	/* submit softirq */
436 	writel((map << 8) | d->hwirq, mpic->base + MPIC_SW_TRIG_INT);
437 }
438 
439 static void mpic_ipi_ack(struct irq_data *d)
440 {
441 	struct mpic *mpic = irq_data_get_irq_chip_data(d);
442 
443 	writel(~BIT(d->hwirq), mpic->per_cpu + MPIC_IN_DRBEL_CAUSE);
444 }
445 
446 static struct irq_chip mpic_ipi_irqchip = {
447 	.name		= "IPI",
448 	.irq_ack	= mpic_ipi_ack,
449 	.irq_mask	= mpic_ipi_mask,
450 	.irq_unmask	= mpic_ipi_unmask,
451 	.ipi_send_mask	= mpic_ipi_send_mask,
452 };
453 
454 static int mpic_ipi_alloc(struct irq_domain *d, unsigned int virq,
455 			  unsigned int nr_irqs, void *args)
456 {
457 	for (unsigned int i = 0; i < nr_irqs; i++) {
458 		irq_set_percpu_devid(virq + i);
459 		irq_domain_set_info(d, virq + i, i, &mpic_ipi_irqchip, d->host_data,
460 				    handle_percpu_devid_irq, NULL, NULL);
461 	}
462 
463 	return 0;
464 }
465 
466 static void mpic_ipi_free(struct irq_domain *d, unsigned int virq,
467 			  unsigned int nr_irqs)
468 {
469 	/* Not freeing IPIs */
470 }
471 
472 static const struct irq_domain_ops mpic_ipi_domain_ops = {
473 	.alloc	= mpic_ipi_alloc,
474 	.free	= mpic_ipi_free,
475 };
476 
477 static void mpic_ipi_resume(struct mpic *mpic)
478 {
479 	for (irq_hw_number_t i = 0; i < IPI_DOORBELL_NR; i++) {
480 		unsigned int virq = irq_find_mapping(mpic->ipi_domain, i);
481 		struct irq_data *d;
482 
483 		if (!virq || !irq_percpu_is_enabled(virq))
484 			continue;
485 
486 		d = irq_domain_get_irq_data(mpic->ipi_domain, virq);
487 		mpic_ipi_unmask(d);
488 	}
489 }
490 
491 static int __init mpic_ipi_init(struct mpic *mpic, struct device_node *node)
492 {
493 	int base_ipi;
494 
495 	mpic->ipi_domain = irq_domain_create_linear(of_node_to_fwnode(node), IPI_DOORBELL_NR,
496 						    &mpic_ipi_domain_ops, mpic);
497 	if (WARN_ON(!mpic->ipi_domain))
498 		return -ENOMEM;
499 
500 	irq_domain_update_bus_token(mpic->ipi_domain, DOMAIN_BUS_IPI);
501 	base_ipi = irq_domain_alloc_irqs(mpic->ipi_domain, IPI_DOORBELL_NR, NUMA_NO_NODE, NULL);
502 	if (WARN_ON(!base_ipi))
503 		return -ENOMEM;
504 
505 	set_smp_ipi_range(base_ipi, IPI_DOORBELL_NR);
506 
507 	return 0;
508 }
509 
510 static int mpic_set_affinity(struct irq_data *d, const struct cpumask *mask_val, bool force)
511 {
512 	struct mpic *mpic = irq_data_get_irq_chip_data(d);
513 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
514 	unsigned int cpu;
515 
516 	/* Select a single core from the affinity mask which is online */
517 	cpu = cpumask_any_and(mask_val, cpu_online_mask);
518 
519 	atomic_io_modify(mpic->base + MPIC_INT_SOURCE_CTL(hwirq),
520 			 MPIC_INT_SOURCE_CPU_MASK, BIT(cpu_logical_map(cpu)));
521 
522 	irq_data_update_effective_affinity(d, cpumask_of(cpu));
523 
524 	return IRQ_SET_MASK_OK;
525 }
526 
527 static void mpic_smp_cpu_init(struct mpic *mpic)
528 {
529 	for (irq_hw_number_t i = 0; i < mpic->domain->hwirq_max; i++)
530 		writel(i, mpic->per_cpu + MPIC_INT_SET_MASK);
531 
532 	if (!mpic_is_ipi_available(mpic))
533 		return;
534 
535 	/* Disable all IPIs */
536 	writel(0, mpic->per_cpu + MPIC_IN_DRBEL_MASK);
537 
538 	/* Clear pending IPIs */
539 	writel(0, mpic->per_cpu + MPIC_IN_DRBEL_CAUSE);
540 
541 	/* Unmask IPI interrupt */
542 	writel(0, mpic->per_cpu + MPIC_INT_CLEAR_MASK);
543 }
544 
545 static void mpic_reenable_percpu(struct mpic *mpic)
546 {
547 	/* Re-enable per-CPU interrupts that were enabled before suspend */
548 	for (irq_hw_number_t i = 0; i < MPIC_PER_CPU_IRQS_NR; i++) {
549 		unsigned int virq = irq_linear_revmap(mpic->domain, i);
550 		struct irq_data *d;
551 
552 		if (!virq || !irq_percpu_is_enabled(virq))
553 			continue;
554 
555 		d = irq_get_irq_data(virq);
556 		mpic_irq_unmask(d);
557 	}
558 
559 	if (mpic_is_ipi_available(mpic))
560 		mpic_ipi_resume(mpic);
561 
562 	mpic_msi_reenable_percpu(mpic);
563 }
564 
565 static int mpic_starting_cpu(unsigned int cpu)
566 {
567 	struct mpic *mpic = irq_get_default_host()->host_data;
568 
569 	mpic_perf_init(mpic);
570 	mpic_smp_cpu_init(mpic);
571 	mpic_reenable_percpu(mpic);
572 
573 	return 0;
574 }
575 
576 static int mpic_cascaded_starting_cpu(unsigned int cpu)
577 {
578 	struct mpic *mpic = mpic_data;
579 
580 	mpic_perf_init(mpic);
581 	mpic_reenable_percpu(mpic);
582 	enable_percpu_irq(mpic->parent_irq, IRQ_TYPE_NONE);
583 
584 	return 0;
585 }
586 #else
587 static void mpic_smp_cpu_init(struct mpic *mpic) {}
588 static void mpic_ipi_resume(struct mpic *mpic) {}
589 #endif
590 
591 static struct irq_chip mpic_irq_chip = {
592 	.name		= "MPIC",
593 	.irq_mask	= mpic_irq_mask,
594 	.irq_mask_ack	= mpic_irq_mask,
595 	.irq_unmask	= mpic_irq_unmask,
596 #ifdef CONFIG_SMP
597 	.irq_set_affinity = mpic_set_affinity,
598 #endif
599 	.flags		= IRQCHIP_SKIP_SET_WAKE | IRQCHIP_MASK_ON_SUSPEND,
600 };
601 
602 static int mpic_irq_map(struct irq_domain *domain, unsigned int virq, irq_hw_number_t hwirq)
603 {
604 	struct mpic *mpic = domain->host_data;
605 
606 	/* IRQs 0 and 1 cannot be mapped, they are handled internally */
607 	if (hwirq <= 1)
608 		return -EINVAL;
609 
610 	irq_set_chip_data(virq, mpic);
611 
612 	mpic_irq_mask(irq_get_irq_data(virq));
613 	if (!mpic_is_percpu_irq(hwirq))
614 		writel(hwirq, mpic->per_cpu + MPIC_INT_CLEAR_MASK);
615 	else
616 		writel(hwirq, mpic->base + MPIC_INT_SET_ENABLE);
617 	irq_set_status_flags(virq, IRQ_LEVEL);
618 
619 	if (mpic_is_percpu_irq(hwirq)) {
620 		irq_set_percpu_devid(virq);
621 		irq_set_chip_and_handler(virq, &mpic_irq_chip, handle_percpu_devid_irq);
622 	} else {
623 		irq_set_chip_and_handler(virq, &mpic_irq_chip, handle_level_irq);
624 		irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(virq)));
625 	}
626 	irq_set_probe(virq);
627 	return 0;
628 }
629 
630 static const struct irq_domain_ops mpic_irq_ops = {
631 	.map	= mpic_irq_map,
632 	.xlate	= irq_domain_xlate_onecell,
633 };
634 
635 #ifdef CONFIG_PCI_MSI
636 static void mpic_handle_msi_irq(struct mpic *mpic)
637 {
638 	unsigned long cause;
639 	unsigned int i;
640 
641 	cause = readl_relaxed(mpic->per_cpu + MPIC_IN_DRBEL_CAUSE);
642 	cause &= mpic->msi_doorbell_mask;
643 	writel(~cause, mpic->per_cpu + MPIC_IN_DRBEL_CAUSE);
644 
645 	for_each_set_bit(i, &cause, BITS_PER_LONG)
646 		generic_handle_domain_irq(mpic->msi_inner_domain, i - mpic->msi_doorbell_start);
647 }
648 #else
649 static void mpic_handle_msi_irq(struct mpic *mpic) {}
650 #endif
651 
652 #ifdef CONFIG_SMP
653 static void mpic_handle_ipi_irq(struct mpic *mpic)
654 {
655 	unsigned long cause;
656 	irq_hw_number_t i;
657 
658 	cause = readl_relaxed(mpic->per_cpu + MPIC_IN_DRBEL_CAUSE);
659 	cause &= IPI_DOORBELL_MASK;
660 
661 	for_each_set_bit(i, &cause, IPI_DOORBELL_NR)
662 		generic_handle_domain_irq(mpic->ipi_domain, i);
663 }
664 #else
665 static inline void mpic_handle_ipi_irq(struct mpic *mpic) {}
666 #endif
667 
668 static void mpic_handle_cascade_irq(struct irq_desc *desc)
669 {
670 	struct mpic *mpic = irq_desc_get_handler_data(desc);
671 	struct irq_chip *chip = irq_desc_get_chip(desc);
672 	unsigned long cause;
673 	u32 irqsrc, cpuid;
674 	irq_hw_number_t i;
675 
676 	chained_irq_enter(chip, desc);
677 
678 	cause = readl_relaxed(mpic->per_cpu + MPIC_PPI_CAUSE);
679 	cpuid = cpu_logical_map(smp_processor_id());
680 
681 	for_each_set_bit(i, &cause, MPIC_PER_CPU_IRQS_NR) {
682 		irqsrc = readl_relaxed(mpic->base + MPIC_INT_SOURCE_CTL(i));
683 
684 		/* Check if the interrupt is not masked on current CPU.
685 		 * Test IRQ (0-1) and FIQ (8-9) mask bits.
686 		 */
687 		if (!(irqsrc & MPIC_INT_IRQ_FIQ_MASK(cpuid)))
688 			continue;
689 
690 		if (i == 0 || i == 1) {
691 			mpic_handle_msi_irq(mpic);
692 			continue;
693 		}
694 
695 		generic_handle_domain_irq(mpic->domain, i);
696 	}
697 
698 	chained_irq_exit(chip, desc);
699 }
700 
701 static void __exception_irq_entry mpic_handle_irq(struct pt_regs *regs)
702 {
703 	struct mpic *mpic = irq_get_default_host()->host_data;
704 	irq_hw_number_t i;
705 	u32 irqstat;
706 
707 	do {
708 		irqstat = readl_relaxed(mpic->per_cpu + MPIC_CPU_INTACK);
709 		i = FIELD_GET(MPIC_CPU_INTACK_IID_MASK, irqstat);
710 
711 		if (i > 1022)
712 			break;
713 
714 		if (i > 1)
715 			generic_handle_domain_irq(mpic->domain, i);
716 
717 		/* MSI handling */
718 		if (i == 1)
719 			mpic_handle_msi_irq(mpic);
720 
721 		/* IPI Handling */
722 		if (i == 0)
723 			mpic_handle_ipi_irq(mpic);
724 	} while (1);
725 }
726 
727 static int mpic_suspend(void)
728 {
729 	struct mpic *mpic = mpic_data;
730 
731 	mpic->doorbell_mask = readl(mpic->per_cpu + MPIC_IN_DRBEL_MASK);
732 
733 	return 0;
734 }
735 
736 static void mpic_resume(void)
737 {
738 	struct mpic *mpic = mpic_data;
739 	bool src0, src1;
740 
741 	/* Re-enable interrupts */
742 	for (irq_hw_number_t i = 0; i < mpic->domain->hwirq_max; i++) {
743 		unsigned int virq = irq_linear_revmap(mpic->domain, i);
744 		struct irq_data *d;
745 
746 		if (!virq)
747 			continue;
748 
749 		d = irq_get_irq_data(virq);
750 
751 		if (!mpic_is_percpu_irq(i)) {
752 			/* Non per-CPU interrupts */
753 			writel(i, mpic->per_cpu + MPIC_INT_CLEAR_MASK);
754 			if (!irqd_irq_disabled(d))
755 				mpic_irq_unmask(d);
756 		} else {
757 			/* Per-CPU interrupts */
758 			writel(i, mpic->base + MPIC_INT_SET_ENABLE);
759 
760 			/*
761 			 * Re-enable on the current CPU, mpic_reenable_percpu()
762 			 * will take care of secondary CPUs when they come up.
763 			 */
764 			if (irq_percpu_is_enabled(virq))
765 				mpic_irq_unmask(d);
766 		}
767 	}
768 
769 	/* Reconfigure doorbells for IPIs and MSIs */
770 	writel(mpic->doorbell_mask, mpic->per_cpu + MPIC_IN_DRBEL_MASK);
771 
772 	if (mpic_is_ipi_available(mpic)) {
773 		src0 = mpic->doorbell_mask & IPI_DOORBELL_MASK;
774 		src1 = mpic->doorbell_mask & PCI_MSI_DOORBELL_MASK;
775 	} else {
776 		src0 = mpic->doorbell_mask & PCI_MSI_FULL_DOORBELL_SRC0_MASK;
777 		src1 = mpic->doorbell_mask & PCI_MSI_FULL_DOORBELL_SRC1_MASK;
778 	}
779 
780 	if (src0)
781 		writel(0, mpic->per_cpu + MPIC_INT_CLEAR_MASK);
782 	if (src1)
783 		writel(1, mpic->per_cpu + MPIC_INT_CLEAR_MASK);
784 
785 	if (mpic_is_ipi_available(mpic))
786 		mpic_ipi_resume(mpic);
787 }
788 
789 static struct syscore_ops mpic_syscore_ops = {
790 	.suspend	= mpic_suspend,
791 	.resume		= mpic_resume,
792 };
793 
794 static int __init mpic_map_region(struct device_node *np, int index,
795 				  void __iomem **base, phys_addr_t *phys_base)
796 {
797 	struct resource res;
798 	int err;
799 
800 	err = of_address_to_resource(np, index, &res);
801 	if (WARN_ON(err))
802 		goto fail;
803 
804 	if (WARN_ON(!request_mem_region(res.start, resource_size(&res), np->full_name))) {
805 		err = -EBUSY;
806 		goto fail;
807 	}
808 
809 	*base = ioremap(res.start, resource_size(&res));
810 	if (WARN_ON(!*base)) {
811 		err = -ENOMEM;
812 		goto fail;
813 	}
814 
815 	if (phys_base)
816 		*phys_base = res.start;
817 
818 	return 0;
819 
820 fail:
821 	pr_err("%pOF: Unable to map resource %d: %pE\n", np, index, ERR_PTR(err));
822 	return err;
823 }
824 
825 static int __init mpic_of_init(struct device_node *node, struct device_node *parent)
826 {
827 	phys_addr_t phys_base;
828 	unsigned int nr_irqs;
829 	struct mpic *mpic;
830 	int err;
831 
832 	mpic = kzalloc(sizeof(*mpic), GFP_KERNEL);
833 	if (WARN_ON(!mpic))
834 		return -ENOMEM;
835 
836 	mpic_data = mpic;
837 
838 	err = mpic_map_region(node, 0, &mpic->base, &phys_base);
839 	if (err)
840 		return err;
841 
842 	err = mpic_map_region(node, 1, &mpic->per_cpu, NULL);
843 	if (err)
844 		return err;
845 
846 	nr_irqs = FIELD_GET(MPIC_INT_CONTROL_NUMINT_MASK, readl(mpic->base + MPIC_INT_CONTROL));
847 
848 	for (irq_hw_number_t i = 0; i < nr_irqs; i++)
849 		writel(i, mpic->base + MPIC_INT_CLEAR_ENABLE);
850 
851 	/*
852 	 * Initialize mpic->parent_irq before calling any other functions, since
853 	 * it is used to distinguish between IPI and non-IPI platforms.
854 	 */
855 	mpic->parent_irq = irq_of_parse_and_map(node, 0);
856 
857 	/*
858 	 * On non-IPI platforms the driver currently supports only the per-CPU
859 	 * interrupts (the first 29 interrupts). See mpic_handle_cascade_irq().
860 	 */
861 	if (!mpic_is_ipi_available(mpic))
862 		nr_irqs = MPIC_PER_CPU_IRQS_NR;
863 
864 	mpic->domain = irq_domain_add_linear(node, nr_irqs, &mpic_irq_ops, mpic);
865 	if (!mpic->domain) {
866 		pr_err("%pOF: Unable to add IRQ domain\n", node);
867 		return -ENOMEM;
868 	}
869 
870 	irq_domain_update_bus_token(mpic->domain, DOMAIN_BUS_WIRED);
871 
872 	/* Setup for the boot CPU */
873 	mpic_perf_init(mpic);
874 	mpic_smp_cpu_init(mpic);
875 
876 	err = mpic_msi_init(mpic, node, phys_base);
877 	if (err) {
878 		pr_err("%pOF: Unable to initialize MSI domain\n", node);
879 		return err;
880 	}
881 
882 	if (mpic_is_ipi_available(mpic)) {
883 		irq_set_default_host(mpic->domain);
884 		set_handle_irq(mpic_handle_irq);
885 #ifdef CONFIG_SMP
886 		err = mpic_ipi_init(mpic, node);
887 		if (err) {
888 			pr_err("%pOF: Unable to initialize IPI domain\n", node);
889 			return err;
890 		}
891 
892 		cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_ARMADA_XP_STARTING,
893 					  "irqchip/armada/ipi:starting",
894 					  mpic_starting_cpu, NULL);
895 #endif
896 	} else {
897 #ifdef CONFIG_SMP
898 		cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_ARMADA_XP_STARTING,
899 					  "irqchip/armada/cascade:starting",
900 					  mpic_cascaded_starting_cpu, NULL);
901 #endif
902 		irq_set_chained_handler_and_data(mpic->parent_irq,
903 						 mpic_handle_cascade_irq, mpic);
904 	}
905 
906 	register_syscore_ops(&mpic_syscore_ops);
907 
908 	return 0;
909 }
910 
911 IRQCHIP_DECLARE(marvell_mpic, "marvell,mpic", mpic_of_init);
912