2 * Copyright (C) 2014-2015 Toradex AG
3 * Author: Stefan Agner <stefan@agner.ch>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
10 * IRQ chip driver for MSCM interrupt router available on Vybrid SoC's.
11 * The interrupt router is between the CPU's interrupt controller and the
12 * peripheral. The router allows to route the peripheral interrupts to
13 * one of the two available CPU's on Vybrid VF6xx SoC's (Cortex-A5 or
14 * Cortex-M4). The router will be configured transparently on a IRQ
17 * o All peripheral interrupts of the Vybrid SoC can be routed to
18 * CPU 0, CPU 1 or both. The routing is useful for dual-core
19 * variants of Vybrid SoC such as VF6xx. This driver routes the
20 * requested interrupt to the CPU currently running on.
22 * o It is required to setup the interrupt router even on single-core
26 #include <linux/cpu_pm.h>
28 #include <linux/irq.h>
29 #include <linux/irqchip.h>
30 #include <linux/irqdomain.h>
31 #include <linux/mfd/syscon.h>
32 #include <dt-bindings/interrupt-controller/arm-gic.h>
34 #include <linux/of_address.h>
35 #include <linux/slab.h>
36 #include <linux/regmap.h>
38 #define MSCM_CPxNUM 0x4
40 #define MSCM_IRSPRC(n) (0x80 + 2 * (n))
41 #define MSCM_IRSPRC_CPEN_MASK 0x3
43 #define MSCM_IRSPRC_NUM 112
45 struct vf610_mscm_ir_chip_data {
46 void __iomem *mscm_ir_base;
48 u16 saved_irsprc[MSCM_IRSPRC_NUM];
52 static struct vf610_mscm_ir_chip_data *mscm_ir_data;
54 static inline void vf610_mscm_ir_save(struct vf610_mscm_ir_chip_data *data)
58 for (i = 0; i < MSCM_IRSPRC_NUM; i++)
59 data->saved_irsprc[i] = readw_relaxed(data->mscm_ir_base + MSCM_IRSPRC(i));
62 static inline void vf610_mscm_ir_restore(struct vf610_mscm_ir_chip_data *data)
66 for (i = 0; i < MSCM_IRSPRC_NUM; i++)
67 writew_relaxed(data->saved_irsprc[i], data->mscm_ir_base + MSCM_IRSPRC(i));
70 static int vf610_mscm_ir_notifier(struct notifier_block *self,
71 unsigned long cmd, void *v)
74 case CPU_CLUSTER_PM_ENTER:
75 vf610_mscm_ir_save(mscm_ir_data);
77 case CPU_CLUSTER_PM_ENTER_FAILED:
78 case CPU_CLUSTER_PM_EXIT:
79 vf610_mscm_ir_restore(mscm_ir_data);
86 static struct notifier_block mscm_ir_notifier_block = {
87 .notifier_call = vf610_mscm_ir_notifier,
90 static void vf610_mscm_ir_enable(struct irq_data *data)
92 irq_hw_number_t hwirq = data->hwirq;
93 struct vf610_mscm_ir_chip_data *chip_data = data->chip_data;
96 irsprc = readw_relaxed(chip_data->mscm_ir_base + MSCM_IRSPRC(hwirq));
97 irsprc &= MSCM_IRSPRC_CPEN_MASK;
99 WARN_ON(irsprc & ~chip_data->cpu_mask);
101 writew_relaxed(chip_data->cpu_mask,
102 chip_data->mscm_ir_base + MSCM_IRSPRC(hwirq));
104 irq_chip_enable_parent(data);
107 static void vf610_mscm_ir_disable(struct irq_data *data)
109 irq_hw_number_t hwirq = data->hwirq;
110 struct vf610_mscm_ir_chip_data *chip_data = data->chip_data;
112 writew_relaxed(0x0, chip_data->mscm_ir_base + MSCM_IRSPRC(hwirq));
114 irq_chip_disable_parent(data);
117 static struct irq_chip vf610_mscm_ir_irq_chip = {
119 .irq_mask = irq_chip_mask_parent,
120 .irq_unmask = irq_chip_unmask_parent,
121 .irq_eoi = irq_chip_eoi_parent,
122 .irq_enable = vf610_mscm_ir_enable,
123 .irq_disable = vf610_mscm_ir_disable,
124 .irq_retrigger = irq_chip_retrigger_hierarchy,
125 .irq_set_affinity = irq_chip_set_affinity_parent,
128 static int vf610_mscm_ir_domain_alloc(struct irq_domain *domain, unsigned int virq,
129 unsigned int nr_irqs, void *arg)
132 irq_hw_number_t hwirq;
133 struct irq_fwspec *fwspec = arg;
134 struct irq_fwspec parent_fwspec;
136 if (!irq_domain_get_of_node(domain->parent))
139 if (fwspec->param_count != 2)
142 hwirq = fwspec->param[0];
143 for (i = 0; i < nr_irqs; i++)
144 irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
145 &vf610_mscm_ir_irq_chip,
148 parent_fwspec.fwnode = domain->parent->fwnode;
150 if (mscm_ir_data->is_nvic) {
151 parent_fwspec.param_count = 1;
152 parent_fwspec.param[0] = fwspec->param[0];
154 parent_fwspec.param_count = 3;
155 parent_fwspec.param[0] = GIC_SPI;
156 parent_fwspec.param[1] = fwspec->param[0];
157 parent_fwspec.param[2] = fwspec->param[1];
160 return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
164 static int vf610_mscm_ir_domain_translate(struct irq_domain *d,
165 struct irq_fwspec *fwspec,
166 unsigned long *hwirq,
169 if (WARN_ON(fwspec->param_count < 2))
171 *hwirq = fwspec->param[0];
172 *type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
176 static const struct irq_domain_ops mscm_irq_domain_ops = {
177 .translate = vf610_mscm_ir_domain_translate,
178 .alloc = vf610_mscm_ir_domain_alloc,
179 .free = irq_domain_free_irqs_common,
182 static int __init vf610_mscm_ir_of_init(struct device_node *node,
183 struct device_node *parent)
185 struct irq_domain *domain, *domain_parent;
186 struct regmap *mscm_cp_regmap;
189 domain_parent = irq_find_host(parent);
190 if (!domain_parent) {
191 pr_err("vf610_mscm_ir: interrupt-parent not found\n");
195 mscm_ir_data = kzalloc(sizeof(*mscm_ir_data), GFP_KERNEL);
199 mscm_ir_data->mscm_ir_base = of_io_request_and_map(node, 0, "mscm-ir");
200 if (IS_ERR(mscm_ir_data->mscm_ir_base)) {
201 pr_err("vf610_mscm_ir: unable to map mscm register\n");
202 ret = PTR_ERR(mscm_ir_data->mscm_ir_base);
206 mscm_cp_regmap = syscon_regmap_lookup_by_phandle(node, "fsl,cpucfg");
207 if (IS_ERR(mscm_cp_regmap)) {
208 ret = PTR_ERR(mscm_cp_regmap);
209 pr_err("vf610_mscm_ir: regmap lookup for cpucfg failed\n");
213 regmap_read(mscm_cp_regmap, MSCM_CPxNUM, &cpuid);
214 mscm_ir_data->cpu_mask = 0x1 << cpuid;
216 domain = irq_domain_add_hierarchy(domain_parent, 0,
217 MSCM_IRSPRC_NUM, node,
218 &mscm_irq_domain_ops, mscm_ir_data);
224 if (of_device_is_compatible(irq_domain_get_of_node(domain->parent),
226 mscm_ir_data->is_nvic = true;
228 cpu_pm_register_notifier(&mscm_ir_notifier_block);
233 iounmap(mscm_ir_data->mscm_ir_base);
238 IRQCHIP_DECLARE(vf610_mscm_ir, "fsl,vf610-mscm-ir", vf610_mscm_ir_of_init);