2 * Marvell Armada 370 and Armada XP SoC IRQ handling
4 * Copyright (C) 2012 Marvell
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>
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.
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>
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>
38 * Overall diagram of the Armada XP interrupt controller:
44 * +---------------+ +---------------+
46 * | per-CPU | | per-CPU |
47 * | mask/unmask | | mask/unmask |
50 * +---------------+ +---------------+
53 * \\_______________________//
55 * +-------------------+
57 * | Global interrupt |
60 * +-------------------+
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
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.
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.
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.
84 * This driver takes the following approach to deal with this:
86 * - For global interrupts:
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
97 * The ->mask() and ->unmask() operations only mask/unmask the
98 * interrupt at the "global" level.
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.
104 * - For per-CPU interrupts
106 * At ->map() time, a per-CPU interrupt is unmasked at the global
109 * The ->mask() and ->unmask() operations mask/unmask the interrupt
110 * at the per-CPU level.
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.
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)
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)
136 #define ARMADA_370_XP_MAX_PER_CPU_IRQS (28)
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
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;
159 static inline bool is_percpu_irq(irq_hw_number_t irq)
161 if (irq <= ARMADA_370_XP_MAX_PER_CPU_IRQS)
169 * For shared global interrupts, mask/unmask global enable bit
170 * For CPU interrupts, mask/unmask the calling CPU's bit
172 static void armada_370_xp_irq_mask(struct irq_data *d)
174 irq_hw_number_t hwirq = irqd_to_hwirq(d);
176 if (!is_percpu_irq(hwirq))
177 writel(hwirq, main_int_base +
178 ARMADA_370_XP_INT_CLEAR_ENABLE_OFFS);
180 writel(hwirq, per_cpu_int_base +
181 ARMADA_370_XP_INT_SET_MASK_OFFS);
184 static void armada_370_xp_irq_unmask(struct irq_data *d)
186 irq_hw_number_t hwirq = irqd_to_hwirq(d);
188 if (!is_percpu_irq(hwirq))
189 writel(hwirq, main_int_base +
190 ARMADA_370_XP_INT_SET_ENABLE_OFFS);
192 writel(hwirq, per_cpu_int_base +
193 ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
196 #ifdef CONFIG_PCI_MSI
198 static struct irq_chip armada_370_xp_msi_irq_chip = {
200 .irq_mask = pci_msi_mask_irq,
201 .irq_unmask = pci_msi_unmask_irq,
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,
210 static void armada_370_xp_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
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);
217 static int armada_370_xp_msi_set_affinity(struct irq_data *irq_data,
218 const struct cpumask *mask, bool force)
223 static struct irq_chip armada_370_xp_msi_bottom_irq_chip = {
225 .irq_compose_msi_msg = armada_370_xp_compose_msi_msg,
226 .irq_set_affinity = armada_370_xp_msi_set_affinity,
229 static int armada_370_xp_msi_alloc(struct irq_domain *domain, unsigned int virq,
230 unsigned int nr_irqs, void *args)
234 mutex_lock(&msi_used_lock);
236 hwirq = bitmap_find_next_zero_area(msi_used, PCI_MSI_DOORBELL_NR,
238 if (hwirq >= PCI_MSI_DOORBELL_NR) {
239 mutex_unlock(&msi_used_lock);
243 bitmap_set(msi_used, hwirq, nr_irqs);
244 mutex_unlock(&msi_used_lock);
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,
256 static void armada_370_xp_msi_free(struct irq_domain *domain,
257 unsigned int virq, unsigned int nr_irqs)
259 struct irq_data *d = irq_domain_get_irq_data(domain, virq);
261 mutex_lock(&msi_used_lock);
262 bitmap_clear(msi_used, d->hwirq, nr_irqs);
263 mutex_unlock(&msi_used_lock);
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,
271 static int armada_370_xp_msi_init(struct device_node *node,
272 phys_addr_t main_int_phys_base)
276 msi_doorbell_addr = main_int_phys_base +
277 ARMADA_370_XP_SW_TRIG_INT_OFFS;
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)
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);
294 reg = readl(per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS)
295 | PCI_MSI_DOORBELL_MASK;
297 writel(reg, per_cpu_int_base +
298 ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
300 /* Unmask IPI interrupt */
301 writel(1, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
306 static inline int armada_370_xp_msi_init(struct device_node *node,
307 phys_addr_t main_int_phys_base)
314 static DEFINE_RAW_SPINLOCK(irq_controller_lock);
316 static int armada_xp_set_affinity(struct irq_data *d,
317 const struct cpumask *mask_val, bool force)
319 irq_hw_number_t hwirq = irqd_to_hwirq(d);
320 unsigned long reg, mask;
323 /* Select a single core from the affinity mask which is online */
324 cpu = cpumask_any_and(mask_val, cpu_online_mask);
325 mask = 1UL << cpu_logical_map(cpu);
327 raw_spin_lock(&irq_controller_lock);
328 reg = readl(main_int_base + ARMADA_370_XP_INT_SOURCE_CTL(hwirq));
329 reg = (reg & (~ARMADA_370_XP_INT_SOURCE_CPU_MASK)) | mask;
330 writel(reg, main_int_base + ARMADA_370_XP_INT_SOURCE_CTL(hwirq));
331 raw_spin_unlock(&irq_controller_lock);
333 irq_data_update_effective_affinity(d, cpumask_of(cpu));
335 return IRQ_SET_MASK_OK;
339 static struct irq_chip armada_370_xp_irq_chip = {
341 .irq_mask = armada_370_xp_irq_mask,
342 .irq_mask_ack = armada_370_xp_irq_mask,
343 .irq_unmask = armada_370_xp_irq_unmask,
345 .irq_set_affinity = armada_xp_set_affinity,
347 .flags = IRQCHIP_SKIP_SET_WAKE | IRQCHIP_MASK_ON_SUSPEND,
350 static int armada_370_xp_mpic_irq_map(struct irq_domain *h,
351 unsigned int virq, irq_hw_number_t hw)
353 armada_370_xp_irq_mask(irq_get_irq_data(virq));
354 if (!is_percpu_irq(hw))
355 writel(hw, per_cpu_int_base +
356 ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
358 writel(hw, main_int_base + ARMADA_370_XP_INT_SET_ENABLE_OFFS);
359 irq_set_status_flags(virq, IRQ_LEVEL);
361 if (is_percpu_irq(hw)) {
362 irq_set_percpu_devid(virq);
363 irq_set_chip_and_handler(virq, &armada_370_xp_irq_chip,
364 handle_percpu_devid_irq);
366 irq_set_chip_and_handler(virq, &armada_370_xp_irq_chip,
368 irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(virq)));
375 static void armada_xp_mpic_smp_cpu_init(void)
380 control = readl(main_int_base + ARMADA_370_XP_INT_CONTROL);
381 nr_irqs = (control >> 2) & 0x3ff;
383 for (i = 0; i < nr_irqs; i++)
384 writel(i, per_cpu_int_base + ARMADA_370_XP_INT_SET_MASK_OFFS);
386 /* Clear pending IPIs */
387 writel(0, per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);
389 /* Enable first 8 IPIs */
390 writel(IPI_DOORBELL_MASK, per_cpu_int_base +
391 ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
393 /* Unmask IPI interrupt */
394 writel(0, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
397 static void armada_xp_mpic_perf_init(void)
399 unsigned long cpuid = cpu_logical_map(smp_processor_id());
401 /* Enable Performance Counter Overflow interrupts */
402 writel(ARMADA_370_XP_INT_CAUSE_PERF(cpuid),
403 per_cpu_int_base + ARMADA_370_XP_INT_FABRIC_MASK_OFFS);
407 static void armada_mpic_send_doorbell(const struct cpumask *mask,
411 unsigned long map = 0;
413 /* Convert our logical CPU mask into a physical one. */
414 for_each_cpu(cpu, mask)
415 map |= 1 << cpu_logical_map(cpu);
418 * Ensure that stores to Normal memory are visible to the
419 * other CPUs before issuing the IPI.
424 writel((map << 8) | irq, main_int_base +
425 ARMADA_370_XP_SW_TRIG_INT_OFFS);
428 static void armada_xp_mpic_reenable_percpu(void)
432 /* Re-enable per-CPU interrupts that were enabled before suspend */
433 for (irq = 0; irq < ARMADA_370_XP_MAX_PER_CPU_IRQS; irq++) {
434 struct irq_data *data;
437 virq = irq_linear_revmap(armada_370_xp_mpic_domain, irq);
441 data = irq_get_irq_data(virq);
443 if (!irq_percpu_is_enabled(virq))
446 armada_370_xp_irq_unmask(data);
450 static int armada_xp_mpic_starting_cpu(unsigned int cpu)
452 armada_xp_mpic_perf_init();
453 armada_xp_mpic_smp_cpu_init();
454 armada_xp_mpic_reenable_percpu();
458 static int mpic_cascaded_starting_cpu(unsigned int cpu)
460 armada_xp_mpic_perf_init();
461 armada_xp_mpic_reenable_percpu();
462 enable_percpu_irq(parent_irq, IRQ_TYPE_NONE);
467 static const struct irq_domain_ops armada_370_xp_mpic_irq_ops = {
468 .map = armada_370_xp_mpic_irq_map,
469 .xlate = irq_domain_xlate_onecell,
472 #ifdef CONFIG_PCI_MSI
473 static void armada_370_xp_handle_msi_irq(struct pt_regs *regs, bool is_chained)
477 msimask = readl_relaxed(per_cpu_int_base +
478 ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS)
479 & PCI_MSI_DOORBELL_MASK;
481 writel(~msimask, per_cpu_int_base +
482 ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);
484 for (msinr = PCI_MSI_DOORBELL_START;
485 msinr < PCI_MSI_DOORBELL_END; msinr++) {
488 if (!(msimask & BIT(msinr)))
492 irq = irq_find_mapping(armada_370_xp_msi_inner_domain,
493 msinr - PCI_MSI_DOORBELL_START);
494 generic_handle_irq(irq);
496 irq = msinr - PCI_MSI_DOORBELL_START;
497 handle_domain_irq(armada_370_xp_msi_inner_domain,
503 static void armada_370_xp_handle_msi_irq(struct pt_regs *r, bool b) {}
506 static void armada_370_xp_mpic_handle_cascade_irq(struct irq_desc *desc)
508 struct irq_chip *chip = irq_desc_get_chip(desc);
509 unsigned long irqmap, irqn, irqsrc, cpuid;
510 unsigned int cascade_irq;
512 chained_irq_enter(chip, desc);
514 irqmap = readl_relaxed(per_cpu_int_base + ARMADA_375_PPI_CAUSE);
515 cpuid = cpu_logical_map(smp_processor_id());
517 for_each_set_bit(irqn, &irqmap, BITS_PER_LONG) {
518 irqsrc = readl_relaxed(main_int_base +
519 ARMADA_370_XP_INT_SOURCE_CTL(irqn));
521 /* Check if the interrupt is not masked on current CPU.
522 * Test IRQ (0-1) and FIQ (8-9) mask bits.
524 if (!(irqsrc & ARMADA_370_XP_INT_IRQ_FIQ_MASK(cpuid)))
528 armada_370_xp_handle_msi_irq(NULL, true);
532 cascade_irq = irq_find_mapping(armada_370_xp_mpic_domain, irqn);
533 generic_handle_irq(cascade_irq);
536 chained_irq_exit(chip, desc);
539 static void __exception_irq_entry
540 armada_370_xp_handle_irq(struct pt_regs *regs)
545 irqstat = readl_relaxed(per_cpu_int_base +
546 ARMADA_370_XP_CPU_INTACK_OFFS);
547 irqnr = irqstat & 0x3FF;
553 handle_domain_irq(armada_370_xp_mpic_domain,
560 armada_370_xp_handle_msi_irq(regs, false);
567 ipimask = readl_relaxed(per_cpu_int_base +
568 ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS)
571 writel(~ipimask, per_cpu_int_base +
572 ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);
574 /* Handle all pending doorbells */
575 for (ipinr = IPI_DOORBELL_START;
576 ipinr < IPI_DOORBELL_END; ipinr++) {
577 if (ipimask & (0x1 << ipinr))
578 handle_IPI(ipinr, regs);
587 static int armada_370_xp_mpic_suspend(void)
589 doorbell_mask_reg = readl(per_cpu_int_base +
590 ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
594 static void armada_370_xp_mpic_resume(void)
599 /* Re-enable interrupts */
600 nirqs = (readl(main_int_base + ARMADA_370_XP_INT_CONTROL) >> 2) & 0x3ff;
601 for (irq = 0; irq < nirqs; irq++) {
602 struct irq_data *data;
605 virq = irq_linear_revmap(armada_370_xp_mpic_domain, irq);
609 data = irq_get_irq_data(virq);
611 if (!is_percpu_irq(irq)) {
612 /* Non per-CPU interrupts */
613 writel(irq, per_cpu_int_base +
614 ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
615 if (!irqd_irq_disabled(data))
616 armada_370_xp_irq_unmask(data);
618 /* Per-CPU interrupts */
619 writel(irq, main_int_base +
620 ARMADA_370_XP_INT_SET_ENABLE_OFFS);
623 * Re-enable on the current CPU,
624 * armada_xp_mpic_reenable_percpu() will take
625 * care of secondary CPUs when they come up.
627 if (irq_percpu_is_enabled(virq))
628 armada_370_xp_irq_unmask(data);
632 /* Reconfigure doorbells for IPIs and MSIs */
633 writel(doorbell_mask_reg,
634 per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
635 if (doorbell_mask_reg & IPI_DOORBELL_MASK)
636 writel(0, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
637 if (doorbell_mask_reg & PCI_MSI_DOORBELL_MASK)
638 writel(1, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
641 static struct syscore_ops armada_370_xp_mpic_syscore_ops = {
642 .suspend = armada_370_xp_mpic_suspend,
643 .resume = armada_370_xp_mpic_resume,
646 static int __init armada_370_xp_mpic_of_init(struct device_node *node,
647 struct device_node *parent)
649 struct resource main_int_res, per_cpu_int_res;
653 BUG_ON(of_address_to_resource(node, 0, &main_int_res));
654 BUG_ON(of_address_to_resource(node, 1, &per_cpu_int_res));
656 BUG_ON(!request_mem_region(main_int_res.start,
657 resource_size(&main_int_res),
659 BUG_ON(!request_mem_region(per_cpu_int_res.start,
660 resource_size(&per_cpu_int_res),
663 main_int_base = ioremap(main_int_res.start,
664 resource_size(&main_int_res));
665 BUG_ON(!main_int_base);
667 per_cpu_int_base = ioremap(per_cpu_int_res.start,
668 resource_size(&per_cpu_int_res));
669 BUG_ON(!per_cpu_int_base);
671 control = readl(main_int_base + ARMADA_370_XP_INT_CONTROL);
672 nr_irqs = (control >> 2) & 0x3ff;
674 for (i = 0; i < nr_irqs; i++)
675 writel(i, main_int_base + ARMADA_370_XP_INT_CLEAR_ENABLE_OFFS);
677 armada_370_xp_mpic_domain =
678 irq_domain_add_linear(node, nr_irqs,
679 &armada_370_xp_mpic_irq_ops, NULL);
680 BUG_ON(!armada_370_xp_mpic_domain);
681 irq_domain_update_bus_token(armada_370_xp_mpic_domain, DOMAIN_BUS_WIRED);
683 /* Setup for the boot CPU */
684 armada_xp_mpic_perf_init();
685 armada_xp_mpic_smp_cpu_init();
687 armada_370_xp_msi_init(node, main_int_res.start);
689 parent_irq = irq_of_parse_and_map(node, 0);
690 if (parent_irq <= 0) {
691 irq_set_default_host(armada_370_xp_mpic_domain);
692 set_handle_irq(armada_370_xp_handle_irq);
694 set_smp_cross_call(armada_mpic_send_doorbell);
695 cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_ARMADA_XP_STARTING,
696 "irqchip/armada/ipi:starting",
697 armada_xp_mpic_starting_cpu, NULL);
701 cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_ARMADA_XP_STARTING,
702 "irqchip/armada/cascade:starting",
703 mpic_cascaded_starting_cpu, NULL);
705 irq_set_chained_handler(parent_irq,
706 armada_370_xp_mpic_handle_cascade_irq);
709 register_syscore_ops(&armada_370_xp_mpic_syscore_ops);
714 IRQCHIP_DECLARE(armada_370_xp_mpic, "marvell,mpic", armada_370_xp_mpic_of_init);