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 
is_percpu_irq(irq_hw_number_t irq)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  */
armada_370_xp_irq_mask(struct irq_data * d)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 
armada_370_xp_irq_unmask(struct irq_data * d)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 
armada_370_xp_compose_msi_msg(struct irq_data * data,struct msi_msg * msg)210 static void armada_370_xp_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
211 {
212 	unsigned int cpu = cpumask_first(irq_data_get_effective_affinity_mask(data));
213 
214 	msg->address_lo = lower_32_bits(msi_doorbell_addr);
215 	msg->address_hi = upper_32_bits(msi_doorbell_addr);
216 	msg->data = BIT(cpu + 8) | (data->hwirq + PCI_MSI_DOORBELL_START);
217 }
218 
armada_370_xp_msi_set_affinity(struct irq_data * irq_data,const struct cpumask * mask,bool force)219 static int armada_370_xp_msi_set_affinity(struct irq_data *irq_data,
220 					  const struct cpumask *mask, bool force)
221 {
222 	unsigned int cpu;
223 
224 	if (!force)
225 		cpu = cpumask_any_and(mask, cpu_online_mask);
226 	else
227 		cpu = cpumask_first(mask);
228 
229 	if (cpu >= nr_cpu_ids)
230 		return -EINVAL;
231 
232 	irq_data_update_effective_affinity(irq_data, cpumask_of(cpu));
233 
234 	return IRQ_SET_MASK_OK;
235 }
236 
237 static struct irq_chip armada_370_xp_msi_bottom_irq_chip = {
238 	.name			= "MPIC MSI",
239 	.irq_compose_msi_msg	= armada_370_xp_compose_msi_msg,
240 	.irq_set_affinity	= armada_370_xp_msi_set_affinity,
241 };
242 
armada_370_xp_msi_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * args)243 static int armada_370_xp_msi_alloc(struct irq_domain *domain, unsigned int virq,
244 				   unsigned int nr_irqs, void *args)
245 {
246 	int hwirq, i;
247 
248 	mutex_lock(&msi_used_lock);
249 	hwirq = bitmap_find_free_region(msi_used, PCI_MSI_DOORBELL_NR,
250 					order_base_2(nr_irqs));
251 	mutex_unlock(&msi_used_lock);
252 
253 	if (hwirq < 0)
254 		return -ENOSPC;
255 
256 	for (i = 0; i < nr_irqs; i++) {
257 		irq_domain_set_info(domain, virq + i, hwirq + i,
258 				    &armada_370_xp_msi_bottom_irq_chip,
259 				    domain->host_data, handle_simple_irq,
260 				    NULL, NULL);
261 	}
262 
263 	return 0;
264 }
265 
armada_370_xp_msi_free(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs)266 static void armada_370_xp_msi_free(struct irq_domain *domain,
267 				   unsigned int virq, unsigned int nr_irqs)
268 {
269 	struct irq_data *d = irq_domain_get_irq_data(domain, virq);
270 
271 	mutex_lock(&msi_used_lock);
272 	bitmap_release_region(msi_used, d->hwirq, order_base_2(nr_irqs));
273 	mutex_unlock(&msi_used_lock);
274 }
275 
276 static const struct irq_domain_ops armada_370_xp_msi_domain_ops = {
277 	.alloc	= armada_370_xp_msi_alloc,
278 	.free	= armada_370_xp_msi_free,
279 };
280 
armada_370_xp_msi_reenable_percpu(void)281 static void armada_370_xp_msi_reenable_percpu(void)
282 {
283 	u32 reg;
284 
285 	/* Enable MSI doorbell mask and combined cpu local interrupt */
286 	reg = readl(per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS)
287 		| PCI_MSI_DOORBELL_MASK;
288 	writel(reg, per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
289 	/* Unmask local doorbell interrupt */
290 	writel(1, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
291 }
292 
armada_370_xp_msi_init(struct device_node * node,phys_addr_t main_int_phys_base)293 static int armada_370_xp_msi_init(struct device_node *node,
294 				  phys_addr_t main_int_phys_base)
295 {
296 	msi_doorbell_addr = main_int_phys_base +
297 		ARMADA_370_XP_SW_TRIG_INT_OFFS;
298 
299 	armada_370_xp_msi_inner_domain =
300 		irq_domain_add_linear(NULL, PCI_MSI_DOORBELL_NR,
301 				      &armada_370_xp_msi_domain_ops, NULL);
302 	if (!armada_370_xp_msi_inner_domain)
303 		return -ENOMEM;
304 
305 	armada_370_xp_msi_domain =
306 		pci_msi_create_irq_domain(of_node_to_fwnode(node),
307 					  &armada_370_xp_msi_domain_info,
308 					  armada_370_xp_msi_inner_domain);
309 	if (!armada_370_xp_msi_domain) {
310 		irq_domain_remove(armada_370_xp_msi_inner_domain);
311 		return -ENOMEM;
312 	}
313 
314 	armada_370_xp_msi_reenable_percpu();
315 
316 	return 0;
317 }
318 #else
armada_370_xp_msi_reenable_percpu(void)319 static void armada_370_xp_msi_reenable_percpu(void) {}
320 
armada_370_xp_msi_init(struct device_node * node,phys_addr_t main_int_phys_base)321 static inline int armada_370_xp_msi_init(struct device_node *node,
322 					 phys_addr_t main_int_phys_base)
323 {
324 	return 0;
325 }
326 #endif
327 
armada_xp_mpic_perf_init(void)328 static void armada_xp_mpic_perf_init(void)
329 {
330 	unsigned long cpuid;
331 
332 	/*
333 	 * This Performance Counter Overflow interrupt is specific for
334 	 * Armada 370 and XP. It is not available on Armada 375, 38x and 39x.
335 	 */
336 	if (!of_machine_is_compatible("marvell,armada-370-xp"))
337 		return;
338 
339 	cpuid = cpu_logical_map(smp_processor_id());
340 
341 	/* Enable Performance Counter Overflow interrupts */
342 	writel(ARMADA_370_XP_INT_CAUSE_PERF(cpuid),
343 	       per_cpu_int_base + ARMADA_370_XP_INT_FABRIC_MASK_OFFS);
344 }
345 
346 #ifdef CONFIG_SMP
347 static struct irq_domain *ipi_domain;
348 
armada_370_xp_ipi_mask(struct irq_data * d)349 static void armada_370_xp_ipi_mask(struct irq_data *d)
350 {
351 	u32 reg;
352 	reg = readl(per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
353 	reg &= ~BIT(d->hwirq);
354 	writel(reg, per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
355 }
356 
armada_370_xp_ipi_unmask(struct irq_data * d)357 static void armada_370_xp_ipi_unmask(struct irq_data *d)
358 {
359 	u32 reg;
360 	reg = readl(per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
361 	reg |= BIT(d->hwirq);
362 	writel(reg, per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
363 }
364 
armada_370_xp_ipi_send_mask(struct irq_data * d,const struct cpumask * mask)365 static void armada_370_xp_ipi_send_mask(struct irq_data *d,
366 					const struct cpumask *mask)
367 {
368 	unsigned long map = 0;
369 	int cpu;
370 
371 	/* Convert our logical CPU mask into a physical one. */
372 	for_each_cpu(cpu, mask)
373 		map |= 1 << cpu_logical_map(cpu);
374 
375 	/*
376 	 * Ensure that stores to Normal memory are visible to the
377 	 * other CPUs before issuing the IPI.
378 	 */
379 	dsb();
380 
381 	/* submit softirq */
382 	writel((map << 8) | d->hwirq, main_int_base +
383 		ARMADA_370_XP_SW_TRIG_INT_OFFS);
384 }
385 
armada_370_xp_ipi_ack(struct irq_data * d)386 static void armada_370_xp_ipi_ack(struct irq_data *d)
387 {
388 	writel(~BIT(d->hwirq), per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);
389 }
390 
391 static struct irq_chip ipi_irqchip = {
392 	.name		= "IPI",
393 	.irq_ack	= armada_370_xp_ipi_ack,
394 	.irq_mask	= armada_370_xp_ipi_mask,
395 	.irq_unmask	= armada_370_xp_ipi_unmask,
396 	.ipi_send_mask	= armada_370_xp_ipi_send_mask,
397 };
398 
armada_370_xp_ipi_alloc(struct irq_domain * d,unsigned int virq,unsigned int nr_irqs,void * args)399 static int armada_370_xp_ipi_alloc(struct irq_domain *d,
400 					 unsigned int virq,
401 					 unsigned int nr_irqs, void *args)
402 {
403 	int i;
404 
405 	for (i = 0; i < nr_irqs; i++) {
406 		irq_set_percpu_devid(virq + i);
407 		irq_domain_set_info(d, virq + i, i, &ipi_irqchip,
408 				    d->host_data,
409 				    handle_percpu_devid_irq,
410 				    NULL, NULL);
411 	}
412 
413 	return 0;
414 }
415 
armada_370_xp_ipi_free(struct irq_domain * d,unsigned int virq,unsigned int nr_irqs)416 static void armada_370_xp_ipi_free(struct irq_domain *d,
417 					 unsigned int virq,
418 					 unsigned int nr_irqs)
419 {
420 	/* Not freeing IPIs */
421 }
422 
423 static const struct irq_domain_ops ipi_domain_ops = {
424 	.alloc	= armada_370_xp_ipi_alloc,
425 	.free	= armada_370_xp_ipi_free,
426 };
427 
ipi_resume(void)428 static void ipi_resume(void)
429 {
430 	int i;
431 
432 	for (i = 0; i < IPI_DOORBELL_END; i++) {
433 		int irq;
434 
435 		irq = irq_find_mapping(ipi_domain, i);
436 		if (irq <= 0)
437 			continue;
438 		if (irq_percpu_is_enabled(irq)) {
439 			struct irq_data *d;
440 			d = irq_domain_get_irq_data(ipi_domain, irq);
441 			armada_370_xp_ipi_unmask(d);
442 		}
443 	}
444 }
445 
armada_xp_ipi_init(struct device_node * node)446 static __init void armada_xp_ipi_init(struct device_node *node)
447 {
448 	int base_ipi;
449 
450 	ipi_domain = irq_domain_create_linear(of_node_to_fwnode(node),
451 					      IPI_DOORBELL_END,
452 					      &ipi_domain_ops, NULL);
453 	if (WARN_ON(!ipi_domain))
454 		return;
455 
456 	irq_domain_update_bus_token(ipi_domain, DOMAIN_BUS_IPI);
457 	base_ipi = irq_domain_alloc_irqs(ipi_domain, IPI_DOORBELL_END, NUMA_NO_NODE, NULL);
458 	if (WARN_ON(!base_ipi))
459 		return;
460 
461 	set_smp_ipi_range(base_ipi, IPI_DOORBELL_END);
462 }
463 
464 static DEFINE_RAW_SPINLOCK(irq_controller_lock);
465 
armada_xp_set_affinity(struct irq_data * d,const struct cpumask * mask_val,bool force)466 static int armada_xp_set_affinity(struct irq_data *d,
467 				  const struct cpumask *mask_val, bool force)
468 {
469 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
470 	unsigned long reg, mask;
471 	int cpu;
472 
473 	/* Select a single core from the affinity mask which is online */
474 	cpu = cpumask_any_and(mask_val, cpu_online_mask);
475 	mask = 1UL << cpu_logical_map(cpu);
476 
477 	raw_spin_lock(&irq_controller_lock);
478 	reg = readl(main_int_base + ARMADA_370_XP_INT_SOURCE_CTL(hwirq));
479 	reg = (reg & (~ARMADA_370_XP_INT_SOURCE_CPU_MASK)) | mask;
480 	writel(reg, main_int_base + ARMADA_370_XP_INT_SOURCE_CTL(hwirq));
481 	raw_spin_unlock(&irq_controller_lock);
482 
483 	irq_data_update_effective_affinity(d, cpumask_of(cpu));
484 
485 	return IRQ_SET_MASK_OK;
486 }
487 
armada_xp_mpic_smp_cpu_init(void)488 static void armada_xp_mpic_smp_cpu_init(void)
489 {
490 	u32 control;
491 	int nr_irqs, i;
492 
493 	control = readl(main_int_base + ARMADA_370_XP_INT_CONTROL);
494 	nr_irqs = (control >> 2) & 0x3ff;
495 
496 	for (i = 0; i < nr_irqs; i++)
497 		writel(i, per_cpu_int_base + ARMADA_370_XP_INT_SET_MASK_OFFS);
498 
499 	/* Disable all IPIs */
500 	writel(0, per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
501 
502 	/* Clear pending IPIs */
503 	writel(0, per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);
504 
505 	/* Unmask IPI interrupt */
506 	writel(0, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
507 }
508 
armada_xp_mpic_reenable_percpu(void)509 static void armada_xp_mpic_reenable_percpu(void)
510 {
511 	unsigned int irq;
512 
513 	/* Re-enable per-CPU interrupts that were enabled before suspend */
514 	for (irq = 0; irq < ARMADA_370_XP_MAX_PER_CPU_IRQS; irq++) {
515 		struct irq_data *data;
516 		int virq;
517 
518 		virq = irq_linear_revmap(armada_370_xp_mpic_domain, irq);
519 		if (virq == 0)
520 			continue;
521 
522 		data = irq_get_irq_data(virq);
523 
524 		if (!irq_percpu_is_enabled(virq))
525 			continue;
526 
527 		armada_370_xp_irq_unmask(data);
528 	}
529 
530 	ipi_resume();
531 
532 	armada_370_xp_msi_reenable_percpu();
533 }
534 
armada_xp_mpic_starting_cpu(unsigned int cpu)535 static int armada_xp_mpic_starting_cpu(unsigned int cpu)
536 {
537 	armada_xp_mpic_perf_init();
538 	armada_xp_mpic_smp_cpu_init();
539 	armada_xp_mpic_reenable_percpu();
540 	return 0;
541 }
542 
mpic_cascaded_starting_cpu(unsigned int cpu)543 static int mpic_cascaded_starting_cpu(unsigned int cpu)
544 {
545 	armada_xp_mpic_perf_init();
546 	armada_xp_mpic_reenable_percpu();
547 	enable_percpu_irq(parent_irq, IRQ_TYPE_NONE);
548 	return 0;
549 }
550 #else
armada_xp_mpic_smp_cpu_init(void)551 static void armada_xp_mpic_smp_cpu_init(void) {}
ipi_resume(void)552 static void ipi_resume(void) {}
553 #endif
554 
555 static struct irq_chip armada_370_xp_irq_chip = {
556 	.name		= "MPIC",
557 	.irq_mask       = armada_370_xp_irq_mask,
558 	.irq_mask_ack   = armada_370_xp_irq_mask,
559 	.irq_unmask     = armada_370_xp_irq_unmask,
560 #ifdef CONFIG_SMP
561 	.irq_set_affinity = armada_xp_set_affinity,
562 #endif
563 	.flags		= IRQCHIP_SKIP_SET_WAKE | IRQCHIP_MASK_ON_SUSPEND,
564 };
565 
armada_370_xp_mpic_irq_map(struct irq_domain * h,unsigned int virq,irq_hw_number_t hw)566 static int armada_370_xp_mpic_irq_map(struct irq_domain *h,
567 				      unsigned int virq, irq_hw_number_t hw)
568 {
569 	armada_370_xp_irq_mask(irq_get_irq_data(virq));
570 	if (!is_percpu_irq(hw))
571 		writel(hw, per_cpu_int_base +
572 			ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
573 	else
574 		writel(hw, main_int_base + ARMADA_370_XP_INT_SET_ENABLE_OFFS);
575 	irq_set_status_flags(virq, IRQ_LEVEL);
576 
577 	if (is_percpu_irq(hw)) {
578 		irq_set_percpu_devid(virq);
579 		irq_set_chip_and_handler(virq, &armada_370_xp_irq_chip,
580 					handle_percpu_devid_irq);
581 	} else {
582 		irq_set_chip_and_handler(virq, &armada_370_xp_irq_chip,
583 					handle_level_irq);
584 		irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(virq)));
585 	}
586 	irq_set_probe(virq);
587 
588 	return 0;
589 }
590 
591 static const struct irq_domain_ops armada_370_xp_mpic_irq_ops = {
592 	.map = armada_370_xp_mpic_irq_map,
593 	.xlate = irq_domain_xlate_onecell,
594 };
595 
596 #ifdef CONFIG_PCI_MSI
armada_370_xp_handle_msi_irq(struct pt_regs * regs,bool is_chained)597 static void armada_370_xp_handle_msi_irq(struct pt_regs *regs, bool is_chained)
598 {
599 	u32 msimask, msinr;
600 
601 	msimask = readl_relaxed(per_cpu_int_base +
602 				ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS)
603 		& PCI_MSI_DOORBELL_MASK;
604 
605 	writel(~msimask, per_cpu_int_base +
606 	       ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);
607 
608 	for (msinr = PCI_MSI_DOORBELL_START;
609 	     msinr < PCI_MSI_DOORBELL_END; msinr++) {
610 		unsigned int irq;
611 
612 		if (!(msimask & BIT(msinr)))
613 			continue;
614 
615 		irq = msinr - PCI_MSI_DOORBELL_START;
616 
617 		generic_handle_domain_irq(armada_370_xp_msi_inner_domain, irq);
618 	}
619 }
620 #else
armada_370_xp_handle_msi_irq(struct pt_regs * r,bool b)621 static void armada_370_xp_handle_msi_irq(struct pt_regs *r, bool b) {}
622 #endif
623 
armada_370_xp_mpic_handle_cascade_irq(struct irq_desc * desc)624 static void armada_370_xp_mpic_handle_cascade_irq(struct irq_desc *desc)
625 {
626 	struct irq_chip *chip = irq_desc_get_chip(desc);
627 	unsigned long irqmap, irqn, irqsrc, cpuid;
628 
629 	chained_irq_enter(chip, desc);
630 
631 	irqmap = readl_relaxed(per_cpu_int_base + ARMADA_375_PPI_CAUSE);
632 	cpuid = cpu_logical_map(smp_processor_id());
633 
634 	for_each_set_bit(irqn, &irqmap, BITS_PER_LONG) {
635 		irqsrc = readl_relaxed(main_int_base +
636 				       ARMADA_370_XP_INT_SOURCE_CTL(irqn));
637 
638 		/* Check if the interrupt is not masked on current CPU.
639 		 * Test IRQ (0-1) and FIQ (8-9) mask bits.
640 		 */
641 		if (!(irqsrc & ARMADA_370_XP_INT_IRQ_FIQ_MASK(cpuid)))
642 			continue;
643 
644 		if (irqn == 1) {
645 			armada_370_xp_handle_msi_irq(NULL, true);
646 			continue;
647 		}
648 
649 		generic_handle_domain_irq(armada_370_xp_mpic_domain, irqn);
650 	}
651 
652 	chained_irq_exit(chip, desc);
653 }
654 
655 static void __exception_irq_entry
armada_370_xp_handle_irq(struct pt_regs * regs)656 armada_370_xp_handle_irq(struct pt_regs *regs)
657 {
658 	u32 irqstat, irqnr;
659 
660 	do {
661 		irqstat = readl_relaxed(per_cpu_int_base +
662 					ARMADA_370_XP_CPU_INTACK_OFFS);
663 		irqnr = irqstat & 0x3FF;
664 
665 		if (irqnr > 1022)
666 			break;
667 
668 		if (irqnr > 1) {
669 			generic_handle_domain_irq(armada_370_xp_mpic_domain,
670 						  irqnr);
671 			continue;
672 		}
673 
674 		/* MSI handling */
675 		if (irqnr == 1)
676 			armada_370_xp_handle_msi_irq(regs, false);
677 
678 #ifdef CONFIG_SMP
679 		/* IPI Handling */
680 		if (irqnr == 0) {
681 			unsigned long ipimask;
682 			int ipi;
683 
684 			ipimask = readl_relaxed(per_cpu_int_base +
685 						ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS)
686 				& IPI_DOORBELL_MASK;
687 
688 			for_each_set_bit(ipi, &ipimask, IPI_DOORBELL_END)
689 				generic_handle_domain_irq(ipi_domain, ipi);
690 		}
691 #endif
692 
693 	} while (1);
694 }
695 
armada_370_xp_mpic_suspend(void)696 static int armada_370_xp_mpic_suspend(void)
697 {
698 	doorbell_mask_reg = readl(per_cpu_int_base +
699 				  ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
700 	return 0;
701 }
702 
armada_370_xp_mpic_resume(void)703 static void armada_370_xp_mpic_resume(void)
704 {
705 	int nirqs;
706 	irq_hw_number_t irq;
707 
708 	/* Re-enable interrupts */
709 	nirqs = (readl(main_int_base + ARMADA_370_XP_INT_CONTROL) >> 2) & 0x3ff;
710 	for (irq = 0; irq < nirqs; irq++) {
711 		struct irq_data *data;
712 		int virq;
713 
714 		virq = irq_linear_revmap(armada_370_xp_mpic_domain, irq);
715 		if (virq == 0)
716 			continue;
717 
718 		data = irq_get_irq_data(virq);
719 
720 		if (!is_percpu_irq(irq)) {
721 			/* Non per-CPU interrupts */
722 			writel(irq, per_cpu_int_base +
723 			       ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
724 			if (!irqd_irq_disabled(data))
725 				armada_370_xp_irq_unmask(data);
726 		} else {
727 			/* Per-CPU interrupts */
728 			writel(irq, main_int_base +
729 			       ARMADA_370_XP_INT_SET_ENABLE_OFFS);
730 
731 			/*
732 			 * Re-enable on the current CPU,
733 			 * armada_xp_mpic_reenable_percpu() will take
734 			 * care of secondary CPUs when they come up.
735 			 */
736 			if (irq_percpu_is_enabled(virq))
737 				armada_370_xp_irq_unmask(data);
738 		}
739 	}
740 
741 	/* Reconfigure doorbells for IPIs and MSIs */
742 	writel(doorbell_mask_reg,
743 	       per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
744 	if (doorbell_mask_reg & IPI_DOORBELL_MASK)
745 		writel(0, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
746 	if (doorbell_mask_reg & PCI_MSI_DOORBELL_MASK)
747 		writel(1, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
748 
749 	ipi_resume();
750 }
751 
752 static struct syscore_ops armada_370_xp_mpic_syscore_ops = {
753 	.suspend	= armada_370_xp_mpic_suspend,
754 	.resume		= armada_370_xp_mpic_resume,
755 };
756 
armada_370_xp_mpic_of_init(struct device_node * node,struct device_node * parent)757 static int __init armada_370_xp_mpic_of_init(struct device_node *node,
758 					     struct device_node *parent)
759 {
760 	struct resource main_int_res, per_cpu_int_res;
761 	int nr_irqs, i;
762 	u32 control;
763 
764 	BUG_ON(of_address_to_resource(node, 0, &main_int_res));
765 	BUG_ON(of_address_to_resource(node, 1, &per_cpu_int_res));
766 
767 	BUG_ON(!request_mem_region(main_int_res.start,
768 				   resource_size(&main_int_res),
769 				   node->full_name));
770 	BUG_ON(!request_mem_region(per_cpu_int_res.start,
771 				   resource_size(&per_cpu_int_res),
772 				   node->full_name));
773 
774 	main_int_base = ioremap(main_int_res.start,
775 				resource_size(&main_int_res));
776 	BUG_ON(!main_int_base);
777 
778 	per_cpu_int_base = ioremap(per_cpu_int_res.start,
779 				   resource_size(&per_cpu_int_res));
780 	BUG_ON(!per_cpu_int_base);
781 
782 	control = readl(main_int_base + ARMADA_370_XP_INT_CONTROL);
783 	nr_irqs = (control >> 2) & 0x3ff;
784 
785 	for (i = 0; i < nr_irqs; i++)
786 		writel(i, main_int_base + ARMADA_370_XP_INT_CLEAR_ENABLE_OFFS);
787 
788 	armada_370_xp_mpic_domain =
789 		irq_domain_add_linear(node, nr_irqs,
790 				&armada_370_xp_mpic_irq_ops, NULL);
791 	BUG_ON(!armada_370_xp_mpic_domain);
792 	irq_domain_update_bus_token(armada_370_xp_mpic_domain, DOMAIN_BUS_WIRED);
793 
794 	/* Setup for the boot CPU */
795 	armada_xp_mpic_perf_init();
796 	armada_xp_mpic_smp_cpu_init();
797 
798 	armada_370_xp_msi_init(node, main_int_res.start);
799 
800 	parent_irq = irq_of_parse_and_map(node, 0);
801 	if (parent_irq <= 0) {
802 		irq_set_default_host(armada_370_xp_mpic_domain);
803 		set_handle_irq(armada_370_xp_handle_irq);
804 #ifdef CONFIG_SMP
805 		armada_xp_ipi_init(node);
806 		cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_ARMADA_XP_STARTING,
807 					  "irqchip/armada/ipi:starting",
808 					  armada_xp_mpic_starting_cpu, NULL);
809 #endif
810 	} else {
811 #ifdef CONFIG_SMP
812 		cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_ARMADA_XP_STARTING,
813 					  "irqchip/armada/cascade:starting",
814 					  mpic_cascaded_starting_cpu, NULL);
815 #endif
816 		irq_set_chained_handler(parent_irq,
817 					armada_370_xp_mpic_handle_cascade_irq);
818 	}
819 
820 	register_syscore_ops(&armada_370_xp_mpic_syscore_ops);
821 
822 	return 0;
823 }
824 
825 IRQCHIP_DECLARE(armada_370_xp_mpic, "marvell,mpic", armada_370_xp_mpic_of_init);
826