1 /*
2  * Marvell Armada 370 and Armada XP SoC IRQ handling
3  *
4  * Copyright (C) 2012 Marvell
5  *
6  * Lior Amsalem <alior@marvell.com>
7  * Gregory CLEMENT <gregory.clement@free-electrons.com>
8  * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
9  * Ben Dooks <ben.dooks@codethink.co.uk>
10  *
11  * This file is licensed under the terms of the GNU General Public
12  * License version 2.  This program is licensed "as is" without any
13  * warranty of any kind, whether express or implied.
14  */
15 
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 <asm/mach/arch.h>
33 #include <asm/exception.h>
34 #include <asm/smp_plat.h>
35 #include <asm/mach/irq.h>
36 
37 /*
38  * Overall diagram of the Armada XP interrupt controller:
39  *
40  *    To CPU 0                 To CPU 1
41  *
42  *       /\                       /\
43  *       ||                       ||
44  * +---------------+     +---------------+
45  * |               |	 |               |
46  * |    per-CPU    |	 |    per-CPU    |
47  * |  mask/unmask  |	 |  mask/unmask  |
48  * |     CPU0      |	 |     CPU1      |
49  * |               |	 |               |
50  * +---------------+	 +---------------+
51  *        /\                       /\
52  *        ||                       ||
53  *        \\_______________________//
54  *                     ||
55  *            +-------------------+
56  *            |                   |
57  *            | Global interrupt  |
58  *            |    mask/unmask    |
59  *            |                   |
60  *            +-------------------+
61  *                     /\
62  *                     ||
63  *               interrupt from
64  *                   device
65  *
66  * The "global interrupt mask/unmask" is modified using the
67  * ARMADA_370_XP_INT_SET_ENABLE_OFFS and
68  * ARMADA_370_XP_INT_CLEAR_ENABLE_OFFS registers, which are relative
69  * to "main_int_base".
70  *
71  * The "per-CPU mask/unmask" is modified using the
72  * ARMADA_370_XP_INT_SET_MASK_OFFS and
73  * ARMADA_370_XP_INT_CLEAR_MASK_OFFS registers, which are relative to
74  * "per_cpu_int_base". This base address points to a special address,
75  * which automatically accesses the registers of the current CPU.
76  *
77  * The per-CPU mask/unmask can also be adjusted using the global
78  * per-interrupt ARMADA_370_XP_INT_SOURCE_CTL register, which we use
79  * to configure interrupt affinity.
80  *
81  * Due to this model, all interrupts need to be mask/unmasked at two
82  * different levels: at the global level and at the per-CPU level.
83  *
84  * This driver takes the following approach to deal with this:
85  *
86  *  - For global interrupts:
87  *
88  *    At ->map() time, a global interrupt is unmasked at the per-CPU
89  *    mask/unmask level. It is therefore unmasked at this level for
90  *    the current CPU, running the ->map() code. This allows to have
91  *    the interrupt unmasked at this level in non-SMP
92  *    configurations. In SMP configurations, the ->set_affinity()
93  *    callback is called, which using the
94  *    ARMADA_370_XP_INT_SOURCE_CTL() readjusts the per-CPU mask/unmask
95  *    for the interrupt.
96  *
97  *    The ->mask() and ->unmask() operations only mask/unmask the
98  *    interrupt at the "global" level.
99  *
100  *    So, a global interrupt is enabled at the per-CPU level as soon
101  *    as it is mapped. At run time, the masking/unmasking takes place
102  *    at the global level.
103  *
104  *  - For per-CPU interrupts
105  *
106  *    At ->map() time, a per-CPU interrupt is unmasked at the global
107  *    mask/unmask level.
108  *
109  *    The ->mask() and ->unmask() operations mask/unmask the interrupt
110  *    at the per-CPU level.
111  *
112  *    So, a per-CPU interrupt is enabled at the global level as soon
113  *    as it is mapped. At run time, the masking/unmasking takes place
114  *    at the per-CPU level.
115  */
116 
117 /* Registers relative to main_int_base */
118 #define ARMADA_370_XP_INT_CONTROL		(0x00)
119 #define ARMADA_370_XP_SW_TRIG_INT_OFFS		(0x04)
120 #define ARMADA_370_XP_INT_SET_ENABLE_OFFS	(0x30)
121 #define ARMADA_370_XP_INT_CLEAR_ENABLE_OFFS	(0x34)
122 #define ARMADA_370_XP_INT_SOURCE_CTL(irq)	(0x100 + irq*4)
123 #define ARMADA_370_XP_INT_SOURCE_CPU_MASK	0xF
124 #define ARMADA_370_XP_INT_IRQ_FIQ_MASK(cpuid)	((BIT(0) | BIT(8)) << cpuid)
125 
126 /* Registers relative to per_cpu_int_base */
127 #define ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS	(0x08)
128 #define ARMADA_370_XP_IN_DRBEL_MSK_OFFS		(0x0c)
129 #define ARMADA_375_PPI_CAUSE			(0x10)
130 #define ARMADA_370_XP_CPU_INTACK_OFFS		(0x44)
131 #define ARMADA_370_XP_INT_SET_MASK_OFFS		(0x48)
132 #define ARMADA_370_XP_INT_CLEAR_MASK_OFFS	(0x4C)
133 #define ARMADA_370_XP_INT_FABRIC_MASK_OFFS	(0x54)
134 #define ARMADA_370_XP_INT_CAUSE_PERF(cpu)	(1 << cpu)
135 
136 #define ARMADA_370_XP_MAX_PER_CPU_IRQS		(28)
137 
138 #define IPI_DOORBELL_START                      (0)
139 #define IPI_DOORBELL_END                        (8)
140 #define IPI_DOORBELL_MASK                       0xFF
141 #define PCI_MSI_DOORBELL_START                  (16)
142 #define PCI_MSI_DOORBELL_NR                     (16)
143 #define PCI_MSI_DOORBELL_END                    (32)
144 #define PCI_MSI_DOORBELL_MASK                   0xFFFF0000
145 
146 static void __iomem *per_cpu_int_base;
147 static void __iomem *main_int_base;
148 static struct irq_domain *armada_370_xp_mpic_domain;
149 static u32 doorbell_mask_reg;
150 static int parent_irq;
151 #ifdef CONFIG_PCI_MSI
152 static struct irq_domain *armada_370_xp_msi_domain;
153 static struct irq_domain *armada_370_xp_msi_inner_domain;
154 static DECLARE_BITMAP(msi_used, PCI_MSI_DOORBELL_NR);
155 static DEFINE_MUTEX(msi_used_lock);
156 static phys_addr_t msi_doorbell_addr;
157 #endif
158 
159 static inline bool is_percpu_irq(irq_hw_number_t irq)
160 {
161 	if (irq <= ARMADA_370_XP_MAX_PER_CPU_IRQS)
162 		return true;
163 
164 	return false;
165 }
166 
167 /*
168  * In SMP mode:
169  * For shared global interrupts, mask/unmask global enable bit
170  * For CPU interrupts, mask/unmask the calling CPU's bit
171  */
172 static void armada_370_xp_irq_mask(struct irq_data *d)
173 {
174 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
175 
176 	if (!is_percpu_irq(hwirq))
177 		writel(hwirq, main_int_base +
178 				ARMADA_370_XP_INT_CLEAR_ENABLE_OFFS);
179 	else
180 		writel(hwirq, per_cpu_int_base +
181 				ARMADA_370_XP_INT_SET_MASK_OFFS);
182 }
183 
184 static void armada_370_xp_irq_unmask(struct irq_data *d)
185 {
186 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
187 
188 	if (!is_percpu_irq(hwirq))
189 		writel(hwirq, main_int_base +
190 				ARMADA_370_XP_INT_SET_ENABLE_OFFS);
191 	else
192 		writel(hwirq, per_cpu_int_base +
193 				ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
194 }
195 
196 #ifdef CONFIG_PCI_MSI
197 
198 static struct irq_chip armada_370_xp_msi_irq_chip = {
199 	.name = "MPIC MSI",
200 	.irq_mask = pci_msi_mask_irq,
201 	.irq_unmask = pci_msi_unmask_irq,
202 };
203 
204 static struct msi_domain_info armada_370_xp_msi_domain_info = {
205 	.flags	= (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
206 		   MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX),
207 	.chip	= &armada_370_xp_msi_irq_chip,
208 };
209 
210 static void armada_370_xp_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
211 {
212 	msg->address_lo = lower_32_bits(msi_doorbell_addr);
213 	msg->address_hi = upper_32_bits(msi_doorbell_addr);
214 	msg->data = 0xf00 | (data->hwirq + PCI_MSI_DOORBELL_START);
215 }
216 
217 static int armada_370_xp_msi_set_affinity(struct irq_data *irq_data,
218 					  const struct cpumask *mask, bool force)
219 {
220 	 return -EINVAL;
221 }
222 
223 static struct irq_chip armada_370_xp_msi_bottom_irq_chip = {
224 	.name			= "MPIC MSI",
225 	.irq_compose_msi_msg	= armada_370_xp_compose_msi_msg,
226 	.irq_set_affinity	= armada_370_xp_msi_set_affinity,
227 };
228 
229 static int armada_370_xp_msi_alloc(struct irq_domain *domain, unsigned int virq,
230 				   unsigned int nr_irqs, void *args)
231 {
232 	int hwirq, i;
233 
234 	mutex_lock(&msi_used_lock);
235 
236 	hwirq = bitmap_find_next_zero_area(msi_used, PCI_MSI_DOORBELL_NR,
237 					   0, nr_irqs, 0);
238 	if (hwirq >= PCI_MSI_DOORBELL_NR) {
239 		mutex_unlock(&msi_used_lock);
240 		return -ENOSPC;
241 	}
242 
243 	bitmap_set(msi_used, hwirq, nr_irqs);
244 	mutex_unlock(&msi_used_lock);
245 
246 	for (i = 0; i < nr_irqs; i++) {
247 		irq_domain_set_info(domain, virq + i, hwirq + i,
248 				    &armada_370_xp_msi_bottom_irq_chip,
249 				    domain->host_data, handle_simple_irq,
250 				    NULL, NULL);
251 	}
252 
253 	return hwirq;
254 }
255 
256 static void armada_370_xp_msi_free(struct irq_domain *domain,
257 				   unsigned int virq, unsigned int nr_irqs)
258 {
259 	struct irq_data *d = irq_domain_get_irq_data(domain, virq);
260 
261 	mutex_lock(&msi_used_lock);
262 	bitmap_clear(msi_used, d->hwirq, nr_irqs);
263 	mutex_unlock(&msi_used_lock);
264 }
265 
266 static const struct irq_domain_ops armada_370_xp_msi_domain_ops = {
267 	.alloc	= armada_370_xp_msi_alloc,
268 	.free	= armada_370_xp_msi_free,
269 };
270 
271 static int armada_370_xp_msi_init(struct device_node *node,
272 				  phys_addr_t main_int_phys_base)
273 {
274 	u32 reg;
275 
276 	msi_doorbell_addr = main_int_phys_base +
277 		ARMADA_370_XP_SW_TRIG_INT_OFFS;
278 
279 	armada_370_xp_msi_inner_domain =
280 		irq_domain_add_linear(NULL, PCI_MSI_DOORBELL_NR,
281 				      &armada_370_xp_msi_domain_ops, NULL);
282 	if (!armada_370_xp_msi_inner_domain)
283 		return -ENOMEM;
284 
285 	armada_370_xp_msi_domain =
286 		pci_msi_create_irq_domain(of_node_to_fwnode(node),
287 					  &armada_370_xp_msi_domain_info,
288 					  armada_370_xp_msi_inner_domain);
289 	if (!armada_370_xp_msi_domain) {
290 		irq_domain_remove(armada_370_xp_msi_inner_domain);
291 		return -ENOMEM;
292 	}
293 
294 	reg = readl(per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS)
295 		| PCI_MSI_DOORBELL_MASK;
296 
297 	writel(reg, per_cpu_int_base +
298 	       ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
299 
300 	/* Unmask IPI interrupt */
301 	writel(1, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
302 
303 	return 0;
304 }
305 #else
306 static inline int armada_370_xp_msi_init(struct device_node *node,
307 					 phys_addr_t main_int_phys_base)
308 {
309 	return 0;
310 }
311 #endif
312 
313 static void armada_xp_mpic_perf_init(void)
314 {
315 	unsigned long cpuid = cpu_logical_map(smp_processor_id());
316 
317 	/* Enable Performance Counter Overflow interrupts */
318 	writel(ARMADA_370_XP_INT_CAUSE_PERF(cpuid),
319 	       per_cpu_int_base + ARMADA_370_XP_INT_FABRIC_MASK_OFFS);
320 }
321 
322 #ifdef CONFIG_SMP
323 static struct irq_domain *ipi_domain;
324 
325 static void armada_370_xp_ipi_mask(struct irq_data *d)
326 {
327 	u32 reg;
328 	reg = readl(per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
329 	reg &= ~BIT(d->hwirq);
330 	writel(reg, per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
331 }
332 
333 static void armada_370_xp_ipi_unmask(struct irq_data *d)
334 {
335 	u32 reg;
336 	reg = readl(per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
337 	reg |= BIT(d->hwirq);
338 	writel(reg, per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
339 }
340 
341 static void armada_370_xp_ipi_send_mask(struct irq_data *d,
342 					const struct cpumask *mask)
343 {
344 	unsigned long map = 0;
345 	int cpu;
346 
347 	/* Convert our logical CPU mask into a physical one. */
348 	for_each_cpu(cpu, mask)
349 		map |= 1 << cpu_logical_map(cpu);
350 
351 	/*
352 	 * Ensure that stores to Normal memory are visible to the
353 	 * other CPUs before issuing the IPI.
354 	 */
355 	dsb();
356 
357 	/* submit softirq */
358 	writel((map << 8) | d->hwirq, main_int_base +
359 		ARMADA_370_XP_SW_TRIG_INT_OFFS);
360 }
361 
362 static void armada_370_xp_ipi_ack(struct irq_data *d)
363 {
364 	writel(~BIT(d->hwirq), per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);
365 }
366 
367 static struct irq_chip ipi_irqchip = {
368 	.name		= "IPI",
369 	.irq_ack	= armada_370_xp_ipi_ack,
370 	.irq_mask	= armada_370_xp_ipi_mask,
371 	.irq_unmask	= armada_370_xp_ipi_unmask,
372 	.ipi_send_mask	= armada_370_xp_ipi_send_mask,
373 };
374 
375 static int armada_370_xp_ipi_alloc(struct irq_domain *d,
376 					 unsigned int virq,
377 					 unsigned int nr_irqs, void *args)
378 {
379 	int i;
380 
381 	for (i = 0; i < nr_irqs; i++) {
382 		irq_set_percpu_devid(virq + i);
383 		irq_domain_set_info(d, virq + i, i, &ipi_irqchip,
384 				    d->host_data,
385 				    handle_percpu_devid_irq,
386 				    NULL, NULL);
387 	}
388 
389 	return 0;
390 }
391 
392 static void armada_370_xp_ipi_free(struct irq_domain *d,
393 					 unsigned int virq,
394 					 unsigned int nr_irqs)
395 {
396 	/* Not freeing IPIs */
397 }
398 
399 static const struct irq_domain_ops ipi_domain_ops = {
400 	.alloc	= armada_370_xp_ipi_alloc,
401 	.free	= armada_370_xp_ipi_free,
402 };
403 
404 static void ipi_resume(void)
405 {
406 	int i;
407 
408 	for (i = 0; i < IPI_DOORBELL_END; i++) {
409 		int irq;
410 
411 		irq = irq_find_mapping(ipi_domain, i);
412 		if (irq <= 0)
413 			continue;
414 		if (irq_percpu_is_enabled(irq)) {
415 			struct irq_data *d;
416 			d = irq_domain_get_irq_data(ipi_domain, irq);
417 			armada_370_xp_ipi_unmask(d);
418 		}
419 	}
420 }
421 
422 static __init void armada_xp_ipi_init(struct device_node *node)
423 {
424 	int base_ipi;
425 
426 	ipi_domain = irq_domain_create_linear(of_node_to_fwnode(node),
427 					      IPI_DOORBELL_END,
428 					      &ipi_domain_ops, NULL);
429 	if (WARN_ON(!ipi_domain))
430 		return;
431 
432 	irq_domain_update_bus_token(ipi_domain, DOMAIN_BUS_IPI);
433 	base_ipi = __irq_domain_alloc_irqs(ipi_domain, -1, IPI_DOORBELL_END,
434 					   NUMA_NO_NODE, NULL, false, NULL);
435 	if (WARN_ON(!base_ipi))
436 		return;
437 
438 	set_smp_ipi_range(base_ipi, IPI_DOORBELL_END);
439 }
440 
441 static DEFINE_RAW_SPINLOCK(irq_controller_lock);
442 
443 static int armada_xp_set_affinity(struct irq_data *d,
444 				  const struct cpumask *mask_val, bool force)
445 {
446 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
447 	unsigned long reg, mask;
448 	int cpu;
449 
450 	/* Select a single core from the affinity mask which is online */
451 	cpu = cpumask_any_and(mask_val, cpu_online_mask);
452 	mask = 1UL << cpu_logical_map(cpu);
453 
454 	raw_spin_lock(&irq_controller_lock);
455 	reg = readl(main_int_base + ARMADA_370_XP_INT_SOURCE_CTL(hwirq));
456 	reg = (reg & (~ARMADA_370_XP_INT_SOURCE_CPU_MASK)) | mask;
457 	writel(reg, main_int_base + ARMADA_370_XP_INT_SOURCE_CTL(hwirq));
458 	raw_spin_unlock(&irq_controller_lock);
459 
460 	irq_data_update_effective_affinity(d, cpumask_of(cpu));
461 
462 	return IRQ_SET_MASK_OK;
463 }
464 
465 static void armada_xp_mpic_smp_cpu_init(void)
466 {
467 	u32 control;
468 	int nr_irqs, i;
469 
470 	control = readl(main_int_base + ARMADA_370_XP_INT_CONTROL);
471 	nr_irqs = (control >> 2) & 0x3ff;
472 
473 	for (i = 0; i < nr_irqs; i++)
474 		writel(i, per_cpu_int_base + ARMADA_370_XP_INT_SET_MASK_OFFS);
475 
476 	/* Disable all IPIs */
477 	writel(0, per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
478 
479 	/* Clear pending IPIs */
480 	writel(0, per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);
481 
482 	/* Unmask IPI interrupt */
483 	writel(0, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
484 }
485 
486 static void armada_xp_mpic_reenable_percpu(void)
487 {
488 	unsigned int irq;
489 
490 	/* Re-enable per-CPU interrupts that were enabled before suspend */
491 	for (irq = 0; irq < ARMADA_370_XP_MAX_PER_CPU_IRQS; irq++) {
492 		struct irq_data *data;
493 		int virq;
494 
495 		virq = irq_linear_revmap(armada_370_xp_mpic_domain, irq);
496 		if (virq == 0)
497 			continue;
498 
499 		data = irq_get_irq_data(virq);
500 
501 		if (!irq_percpu_is_enabled(virq))
502 			continue;
503 
504 		armada_370_xp_irq_unmask(data);
505 	}
506 
507 	ipi_resume();
508 }
509 
510 static int armada_xp_mpic_starting_cpu(unsigned int cpu)
511 {
512 	armada_xp_mpic_perf_init();
513 	armada_xp_mpic_smp_cpu_init();
514 	armada_xp_mpic_reenable_percpu();
515 	return 0;
516 }
517 
518 static int mpic_cascaded_starting_cpu(unsigned int cpu)
519 {
520 	armada_xp_mpic_perf_init();
521 	armada_xp_mpic_reenable_percpu();
522 	enable_percpu_irq(parent_irq, IRQ_TYPE_NONE);
523 	return 0;
524 }
525 #else
526 static void armada_xp_mpic_smp_cpu_init(void) {}
527 static void ipi_resume(void) {}
528 #endif
529 
530 static struct irq_chip armada_370_xp_irq_chip = {
531 	.name		= "MPIC",
532 	.irq_mask       = armada_370_xp_irq_mask,
533 	.irq_mask_ack   = armada_370_xp_irq_mask,
534 	.irq_unmask     = armada_370_xp_irq_unmask,
535 #ifdef CONFIG_SMP
536 	.irq_set_affinity = armada_xp_set_affinity,
537 #endif
538 	.flags		= IRQCHIP_SKIP_SET_WAKE | IRQCHIP_MASK_ON_SUSPEND,
539 };
540 
541 static int armada_370_xp_mpic_irq_map(struct irq_domain *h,
542 				      unsigned int virq, irq_hw_number_t hw)
543 {
544 	armada_370_xp_irq_mask(irq_get_irq_data(virq));
545 	if (!is_percpu_irq(hw))
546 		writel(hw, per_cpu_int_base +
547 			ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
548 	else
549 		writel(hw, main_int_base + ARMADA_370_XP_INT_SET_ENABLE_OFFS);
550 	irq_set_status_flags(virq, IRQ_LEVEL);
551 
552 	if (is_percpu_irq(hw)) {
553 		irq_set_percpu_devid(virq);
554 		irq_set_chip_and_handler(virq, &armada_370_xp_irq_chip,
555 					handle_percpu_devid_irq);
556 	} else {
557 		irq_set_chip_and_handler(virq, &armada_370_xp_irq_chip,
558 					handle_level_irq);
559 		irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(virq)));
560 	}
561 	irq_set_probe(virq);
562 
563 	return 0;
564 }
565 
566 static const struct irq_domain_ops armada_370_xp_mpic_irq_ops = {
567 	.map = armada_370_xp_mpic_irq_map,
568 	.xlate = irq_domain_xlate_onecell,
569 };
570 
571 #ifdef CONFIG_PCI_MSI
572 static void armada_370_xp_handle_msi_irq(struct pt_regs *regs, bool is_chained)
573 {
574 	u32 msimask, msinr;
575 
576 	msimask = readl_relaxed(per_cpu_int_base +
577 				ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS)
578 		& PCI_MSI_DOORBELL_MASK;
579 
580 	writel(~msimask, per_cpu_int_base +
581 	       ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);
582 
583 	for (msinr = PCI_MSI_DOORBELL_START;
584 	     msinr < PCI_MSI_DOORBELL_END; msinr++) {
585 		unsigned int irq;
586 
587 		if (!(msimask & BIT(msinr)))
588 			continue;
589 
590 		irq = msinr - PCI_MSI_DOORBELL_START;
591 
592 		generic_handle_domain_irq(armada_370_xp_msi_inner_domain, irq);
593 	}
594 }
595 #else
596 static void armada_370_xp_handle_msi_irq(struct pt_regs *r, bool b) {}
597 #endif
598 
599 static void armada_370_xp_mpic_handle_cascade_irq(struct irq_desc *desc)
600 {
601 	struct irq_chip *chip = irq_desc_get_chip(desc);
602 	unsigned long irqmap, irqn, irqsrc, cpuid;
603 
604 	chained_irq_enter(chip, desc);
605 
606 	irqmap = readl_relaxed(per_cpu_int_base + ARMADA_375_PPI_CAUSE);
607 	cpuid = cpu_logical_map(smp_processor_id());
608 
609 	for_each_set_bit(irqn, &irqmap, BITS_PER_LONG) {
610 		irqsrc = readl_relaxed(main_int_base +
611 				       ARMADA_370_XP_INT_SOURCE_CTL(irqn));
612 
613 		/* Check if the interrupt is not masked on current CPU.
614 		 * Test IRQ (0-1) and FIQ (8-9) mask bits.
615 		 */
616 		if (!(irqsrc & ARMADA_370_XP_INT_IRQ_FIQ_MASK(cpuid)))
617 			continue;
618 
619 		if (irqn == 1) {
620 			armada_370_xp_handle_msi_irq(NULL, true);
621 			continue;
622 		}
623 
624 		generic_handle_domain_irq(armada_370_xp_mpic_domain, irqn);
625 	}
626 
627 	chained_irq_exit(chip, desc);
628 }
629 
630 static void __exception_irq_entry
631 armada_370_xp_handle_irq(struct pt_regs *regs)
632 {
633 	u32 irqstat, irqnr;
634 
635 	do {
636 		irqstat = readl_relaxed(per_cpu_int_base +
637 					ARMADA_370_XP_CPU_INTACK_OFFS);
638 		irqnr = irqstat & 0x3FF;
639 
640 		if (irqnr > 1022)
641 			break;
642 
643 		if (irqnr > 1) {
644 			generic_handle_domain_irq(armada_370_xp_mpic_domain,
645 						  irqnr);
646 			continue;
647 		}
648 
649 		/* MSI handling */
650 		if (irqnr == 1)
651 			armada_370_xp_handle_msi_irq(regs, false);
652 
653 #ifdef CONFIG_SMP
654 		/* IPI Handling */
655 		if (irqnr == 0) {
656 			unsigned long ipimask;
657 			int ipi;
658 
659 			ipimask = readl_relaxed(per_cpu_int_base +
660 						ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS)
661 				& IPI_DOORBELL_MASK;
662 
663 			for_each_set_bit(ipi, &ipimask, IPI_DOORBELL_END)
664 				generic_handle_domain_irq(ipi_domain, ipi);
665 		}
666 #endif
667 
668 	} while (1);
669 }
670 
671 static int armada_370_xp_mpic_suspend(void)
672 {
673 	doorbell_mask_reg = readl(per_cpu_int_base +
674 				  ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
675 	return 0;
676 }
677 
678 static void armada_370_xp_mpic_resume(void)
679 {
680 	int nirqs;
681 	irq_hw_number_t irq;
682 
683 	/* Re-enable interrupts */
684 	nirqs = (readl(main_int_base + ARMADA_370_XP_INT_CONTROL) >> 2) & 0x3ff;
685 	for (irq = 0; irq < nirqs; irq++) {
686 		struct irq_data *data;
687 		int virq;
688 
689 		virq = irq_linear_revmap(armada_370_xp_mpic_domain, irq);
690 		if (virq == 0)
691 			continue;
692 
693 		data = irq_get_irq_data(virq);
694 
695 		if (!is_percpu_irq(irq)) {
696 			/* Non per-CPU interrupts */
697 			writel(irq, per_cpu_int_base +
698 			       ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
699 			if (!irqd_irq_disabled(data))
700 				armada_370_xp_irq_unmask(data);
701 		} else {
702 			/* Per-CPU interrupts */
703 			writel(irq, main_int_base +
704 			       ARMADA_370_XP_INT_SET_ENABLE_OFFS);
705 
706 			/*
707 			 * Re-enable on the current CPU,
708 			 * armada_xp_mpic_reenable_percpu() will take
709 			 * care of secondary CPUs when they come up.
710 			 */
711 			if (irq_percpu_is_enabled(virq))
712 				armada_370_xp_irq_unmask(data);
713 		}
714 	}
715 
716 	/* Reconfigure doorbells for IPIs and MSIs */
717 	writel(doorbell_mask_reg,
718 	       per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
719 	if (doorbell_mask_reg & IPI_DOORBELL_MASK)
720 		writel(0, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
721 	if (doorbell_mask_reg & PCI_MSI_DOORBELL_MASK)
722 		writel(1, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
723 
724 	ipi_resume();
725 }
726 
727 static struct syscore_ops armada_370_xp_mpic_syscore_ops = {
728 	.suspend	= armada_370_xp_mpic_suspend,
729 	.resume		= armada_370_xp_mpic_resume,
730 };
731 
732 static int __init armada_370_xp_mpic_of_init(struct device_node *node,
733 					     struct device_node *parent)
734 {
735 	struct resource main_int_res, per_cpu_int_res;
736 	int nr_irqs, i;
737 	u32 control;
738 
739 	BUG_ON(of_address_to_resource(node, 0, &main_int_res));
740 	BUG_ON(of_address_to_resource(node, 1, &per_cpu_int_res));
741 
742 	BUG_ON(!request_mem_region(main_int_res.start,
743 				   resource_size(&main_int_res),
744 				   node->full_name));
745 	BUG_ON(!request_mem_region(per_cpu_int_res.start,
746 				   resource_size(&per_cpu_int_res),
747 				   node->full_name));
748 
749 	main_int_base = ioremap(main_int_res.start,
750 				resource_size(&main_int_res));
751 	BUG_ON(!main_int_base);
752 
753 	per_cpu_int_base = ioremap(per_cpu_int_res.start,
754 				   resource_size(&per_cpu_int_res));
755 	BUG_ON(!per_cpu_int_base);
756 
757 	control = readl(main_int_base + ARMADA_370_XP_INT_CONTROL);
758 	nr_irqs = (control >> 2) & 0x3ff;
759 
760 	for (i = 0; i < nr_irqs; i++)
761 		writel(i, main_int_base + ARMADA_370_XP_INT_CLEAR_ENABLE_OFFS);
762 
763 	armada_370_xp_mpic_domain =
764 		irq_domain_add_linear(node, nr_irqs,
765 				&armada_370_xp_mpic_irq_ops, NULL);
766 	BUG_ON(!armada_370_xp_mpic_domain);
767 	irq_domain_update_bus_token(armada_370_xp_mpic_domain, DOMAIN_BUS_WIRED);
768 
769 	/* Setup for the boot CPU */
770 	armada_xp_mpic_perf_init();
771 	armada_xp_mpic_smp_cpu_init();
772 
773 	armada_370_xp_msi_init(node, main_int_res.start);
774 
775 	parent_irq = irq_of_parse_and_map(node, 0);
776 	if (parent_irq <= 0) {
777 		irq_set_default_host(armada_370_xp_mpic_domain);
778 		set_handle_irq(armada_370_xp_handle_irq);
779 #ifdef CONFIG_SMP
780 		armada_xp_ipi_init(node);
781 		cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_ARMADA_XP_STARTING,
782 					  "irqchip/armada/ipi:starting",
783 					  armada_xp_mpic_starting_cpu, NULL);
784 #endif
785 	} else {
786 #ifdef CONFIG_SMP
787 		cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_ARMADA_XP_STARTING,
788 					  "irqchip/armada/cascade:starting",
789 					  mpic_cascaded_starting_cpu, NULL);
790 #endif
791 		irq_set_chained_handler(parent_irq,
792 					armada_370_xp_mpic_handle_cascade_irq);
793 	}
794 
795 	register_syscore_ops(&armada_370_xp_mpic_syscore_ops);
796 
797 	return 0;
798 }
799 
800 IRQCHIP_DECLARE(armada_370_xp_mpic, "marvell,mpic", armada_370_xp_mpic_of_init);
801