xref: /linux/drivers/irqchip/irq-imx-gpcv2.c (revision b6ebbac51bedf9e98e837688bc838f400196da5e)
1 /*
2  * Copyright (C) 2015 Freescale Semiconductor, Inc.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8 
9 #include <linux/of_address.h>
10 #include <linux/of_irq.h>
11 #include <linux/slab.h>
12 #include <linux/irqchip.h>
13 #include <linux/syscore_ops.h>
14 
15 #define IMR_NUM			4
16 #define GPC_MAX_IRQS            (IMR_NUM * 32)
17 
18 #define GPC_IMR1_CORE0		0x30
19 #define GPC_IMR1_CORE1		0x40
20 
21 struct gpcv2_irqchip_data {
22 	struct raw_spinlock	rlock;
23 	void __iomem		*gpc_base;
24 	u32			wakeup_sources[IMR_NUM];
25 	u32			saved_irq_mask[IMR_NUM];
26 	u32			cpu2wakeup;
27 };
28 
29 static struct gpcv2_irqchip_data *imx_gpcv2_instance;
30 
31 /*
32  * Interface for the low level wakeup code.
33  */
34 u32 imx_gpcv2_get_wakeup_source(u32 **sources)
35 {
36 	if (!imx_gpcv2_instance)
37 		return 0;
38 
39 	if (sources)
40 		*sources = imx_gpcv2_instance->wakeup_sources;
41 
42 	return IMR_NUM;
43 }
44 
45 static int gpcv2_wakeup_source_save(void)
46 {
47 	struct gpcv2_irqchip_data *cd;
48 	void __iomem *reg;
49 	int i;
50 
51 	cd = imx_gpcv2_instance;
52 	if (!cd)
53 		return 0;
54 
55 	for (i = 0; i < IMR_NUM; i++) {
56 		reg = cd->gpc_base + cd->cpu2wakeup + i * 4;
57 		cd->saved_irq_mask[i] = readl_relaxed(reg);
58 		writel_relaxed(cd->wakeup_sources[i], reg);
59 	}
60 
61 	return 0;
62 }
63 
64 static void gpcv2_wakeup_source_restore(void)
65 {
66 	struct gpcv2_irqchip_data *cd;
67 	void __iomem *reg;
68 	int i;
69 
70 	cd = imx_gpcv2_instance;
71 	if (!cd)
72 		return;
73 
74 	for (i = 0; i < IMR_NUM; i++) {
75 		reg = cd->gpc_base + cd->cpu2wakeup + i * 4;
76 		writel_relaxed(cd->saved_irq_mask[i], reg);
77 	}
78 }
79 
80 static struct syscore_ops imx_gpcv2_syscore_ops = {
81 	.suspend	= gpcv2_wakeup_source_save,
82 	.resume		= gpcv2_wakeup_source_restore,
83 };
84 
85 static int imx_gpcv2_irq_set_wake(struct irq_data *d, unsigned int on)
86 {
87 	struct gpcv2_irqchip_data *cd = d->chip_data;
88 	unsigned int idx = d->hwirq / 32;
89 	unsigned long flags;
90 	void __iomem *reg;
91 	u32 mask, val;
92 
93 	raw_spin_lock_irqsave(&cd->rlock, flags);
94 	reg = cd->gpc_base + cd->cpu2wakeup + idx * 4;
95 	mask = 1 << d->hwirq % 32;
96 	val = cd->wakeup_sources[idx];
97 
98 	cd->wakeup_sources[idx] = on ? (val & ~mask) : (val | mask);
99 	raw_spin_unlock_irqrestore(&cd->rlock, flags);
100 
101 	/*
102 	 * Do *not* call into the parent, as the GIC doesn't have any
103 	 * wake-up facility...
104 	 */
105 
106 	return 0;
107 }
108 
109 static void imx_gpcv2_irq_unmask(struct irq_data *d)
110 {
111 	struct gpcv2_irqchip_data *cd = d->chip_data;
112 	void __iomem *reg;
113 	u32 val;
114 
115 	raw_spin_lock(&cd->rlock);
116 	reg = cd->gpc_base + cd->cpu2wakeup + d->hwirq / 32 * 4;
117 	val = readl_relaxed(reg);
118 	val &= ~(1 << d->hwirq % 32);
119 	writel_relaxed(val, reg);
120 	raw_spin_unlock(&cd->rlock);
121 
122 	irq_chip_unmask_parent(d);
123 }
124 
125 static void imx_gpcv2_irq_mask(struct irq_data *d)
126 {
127 	struct gpcv2_irqchip_data *cd = d->chip_data;
128 	void __iomem *reg;
129 	u32 val;
130 
131 	raw_spin_lock(&cd->rlock);
132 	reg = cd->gpc_base + cd->cpu2wakeup + d->hwirq / 32 * 4;
133 	val = readl_relaxed(reg);
134 	val |= 1 << (d->hwirq % 32);
135 	writel_relaxed(val, reg);
136 	raw_spin_unlock(&cd->rlock);
137 
138 	irq_chip_mask_parent(d);
139 }
140 
141 static struct irq_chip gpcv2_irqchip_data_chip = {
142 	.name			= "GPCv2",
143 	.irq_eoi		= irq_chip_eoi_parent,
144 	.irq_mask		= imx_gpcv2_irq_mask,
145 	.irq_unmask		= imx_gpcv2_irq_unmask,
146 	.irq_set_wake		= imx_gpcv2_irq_set_wake,
147 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
148 #ifdef CONFIG_SMP
149 	.irq_set_affinity	= irq_chip_set_affinity_parent,
150 #endif
151 };
152 
153 static int imx_gpcv2_domain_translate(struct irq_domain *d,
154 				      struct irq_fwspec *fwspec,
155 				      unsigned long *hwirq,
156 				      unsigned int *type)
157 {
158 	if (is_of_node(fwspec->fwnode)) {
159 		if (fwspec->param_count != 3)
160 			return -EINVAL;
161 
162 		/* No PPI should point to this domain */
163 		if (fwspec->param[0] != 0)
164 			return -EINVAL;
165 
166 		*hwirq = fwspec->param[1];
167 		*type = fwspec->param[2];
168 		return 0;
169 	}
170 
171 	return -EINVAL;
172 }
173 
174 static int imx_gpcv2_domain_alloc(struct irq_domain *domain,
175 				  unsigned int irq, unsigned int nr_irqs,
176 				  void *data)
177 {
178 	struct irq_fwspec *fwspec = data;
179 	struct irq_fwspec parent_fwspec;
180 	irq_hw_number_t hwirq;
181 	unsigned int type;
182 	int err;
183 	int i;
184 
185 	err = imx_gpcv2_domain_translate(domain, fwspec, &hwirq, &type);
186 	if (err)
187 		return err;
188 
189 	if (hwirq >= GPC_MAX_IRQS)
190 		return -EINVAL;
191 
192 	for (i = 0; i < nr_irqs; i++) {
193 		irq_domain_set_hwirq_and_chip(domain, irq + i, hwirq + i,
194 				&gpcv2_irqchip_data_chip, domain->host_data);
195 	}
196 
197 	parent_fwspec = *fwspec;
198 	parent_fwspec.fwnode = domain->parent->fwnode;
199 	return irq_domain_alloc_irqs_parent(domain, irq, nr_irqs,
200 					    &parent_fwspec);
201 }
202 
203 static struct irq_domain_ops gpcv2_irqchip_data_domain_ops = {
204 	.translate	= imx_gpcv2_domain_translate,
205 	.alloc		= imx_gpcv2_domain_alloc,
206 	.free		= irq_domain_free_irqs_common,
207 };
208 
209 static int __init imx_gpcv2_irqchip_init(struct device_node *node,
210 			       struct device_node *parent)
211 {
212 	struct irq_domain *parent_domain, *domain;
213 	struct gpcv2_irqchip_data *cd;
214 	int i;
215 
216 	if (!parent) {
217 		pr_err("%s: no parent, giving up\n", node->full_name);
218 		return -ENODEV;
219 	}
220 
221 	parent_domain = irq_find_host(parent);
222 	if (!parent_domain) {
223 		pr_err("%s: unable to get parent domain\n", node->full_name);
224 		return -ENXIO;
225 	}
226 
227 	cd = kzalloc(sizeof(struct gpcv2_irqchip_data), GFP_KERNEL);
228 	if (!cd) {
229 		pr_err("kzalloc failed!\n");
230 		return -ENOMEM;
231 	}
232 
233 	cd->gpc_base = of_iomap(node, 0);
234 	if (!cd->gpc_base) {
235 		pr_err("fsl-gpcv2: unable to map gpc registers\n");
236 		kfree(cd);
237 		return -ENOMEM;
238 	}
239 
240 	domain = irq_domain_add_hierarchy(parent_domain, 0, GPC_MAX_IRQS,
241 				node, &gpcv2_irqchip_data_domain_ops, cd);
242 	if (!domain) {
243 		iounmap(cd->gpc_base);
244 		kfree(cd);
245 		return -ENOMEM;
246 	}
247 	irq_set_default_host(domain);
248 
249 	/* Initially mask all interrupts */
250 	for (i = 0; i < IMR_NUM; i++) {
251 		writel_relaxed(~0, cd->gpc_base + GPC_IMR1_CORE0 + i * 4);
252 		writel_relaxed(~0, cd->gpc_base + GPC_IMR1_CORE1 + i * 4);
253 		cd->wakeup_sources[i] = ~0;
254 	}
255 
256 	/* Let CORE0 as the default CPU to wake up by GPC */
257 	cd->cpu2wakeup = GPC_IMR1_CORE0;
258 
259 	/*
260 	 * Due to hardware design failure, need to make sure GPR
261 	 * interrupt(#32) is unmasked during RUN mode to avoid entering
262 	 * DSM by mistake.
263 	 */
264 	writel_relaxed(~0x1, cd->gpc_base + cd->cpu2wakeup);
265 
266 	imx_gpcv2_instance = cd;
267 	register_syscore_ops(&imx_gpcv2_syscore_ops);
268 
269 	return 0;
270 }
271 
272 IRQCHIP_DECLARE(imx_gpcv2, "fsl,imx7d-gpc", imx_gpcv2_irqchip_init);
273