xref: /linux/drivers/irqchip/irq-imx-gpcv2.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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_xlate(struct irq_domain *domain,
154 				struct device_node *controller,
155 				const u32 *intspec,
156 				unsigned int intsize,
157 				unsigned long *out_hwirq,
158 				unsigned int *out_type)
159 {
160 	/* Shouldn't happen, really... */
161 	if (domain->of_node != controller)
162 		return -EINVAL;
163 
164 	/* Not GIC compliant */
165 	if (intsize != 3)
166 		return -EINVAL;
167 
168 	/* No PPI should point to this domain */
169 	if (intspec[0] != 0)
170 		return -EINVAL;
171 
172 	*out_hwirq = intspec[1];
173 	*out_type = intspec[2];
174 	return 0;
175 }
176 
177 static int imx_gpcv2_domain_alloc(struct irq_domain *domain,
178 				  unsigned int irq, unsigned int nr_irqs,
179 				  void *data)
180 {
181 	struct of_phandle_args *args = data;
182 	struct of_phandle_args parent_args;
183 	irq_hw_number_t hwirq;
184 	int i;
185 
186 	/* Not GIC compliant */
187 	if (args->args_count != 3)
188 		return -EINVAL;
189 
190 	/* No PPI should point to this domain */
191 	if (args->args[0] != 0)
192 		return -EINVAL;
193 
194 	/* Can't deal with this */
195 	hwirq = args->args[1];
196 	if (hwirq >= GPC_MAX_IRQS)
197 		return -EINVAL;
198 
199 	for (i = 0; i < nr_irqs; i++) {
200 		irq_domain_set_hwirq_and_chip(domain, irq + i, hwirq + i,
201 				&gpcv2_irqchip_data_chip, domain->host_data);
202 	}
203 
204 	parent_args = *args;
205 	parent_args.np = domain->parent->of_node;
206 	return irq_domain_alloc_irqs_parent(domain, irq, nr_irqs, &parent_args);
207 }
208 
209 static struct irq_domain_ops gpcv2_irqchip_data_domain_ops = {
210 	.xlate	= imx_gpcv2_domain_xlate,
211 	.alloc	= imx_gpcv2_domain_alloc,
212 	.free	= irq_domain_free_irqs_common,
213 };
214 
215 static int __init imx_gpcv2_irqchip_init(struct device_node *node,
216 			       struct device_node *parent)
217 {
218 	struct irq_domain *parent_domain, *domain;
219 	struct gpcv2_irqchip_data *cd;
220 	int i;
221 
222 	if (!parent) {
223 		pr_err("%s: no parent, giving up\n", node->full_name);
224 		return -ENODEV;
225 	}
226 
227 	parent_domain = irq_find_host(parent);
228 	if (!parent_domain) {
229 		pr_err("%s: unable to get parent domain\n", node->full_name);
230 		return -ENXIO;
231 	}
232 
233 	cd = kzalloc(sizeof(struct gpcv2_irqchip_data), GFP_KERNEL);
234 	if (!cd) {
235 		pr_err("kzalloc failed!\n");
236 		return -ENOMEM;
237 	}
238 
239 	cd->gpc_base = of_iomap(node, 0);
240 	if (!cd->gpc_base) {
241 		pr_err("fsl-gpcv2: unable to map gpc registers\n");
242 		kfree(cd);
243 		return -ENOMEM;
244 	}
245 
246 	domain = irq_domain_add_hierarchy(parent_domain, 0, GPC_MAX_IRQS,
247 				node, &gpcv2_irqchip_data_domain_ops, cd);
248 	if (!domain) {
249 		iounmap(cd->gpc_base);
250 		kfree(cd);
251 		return -ENOMEM;
252 	}
253 	irq_set_default_host(domain);
254 
255 	/* Initially mask all interrupts */
256 	for (i = 0; i < IMR_NUM; i++) {
257 		writel_relaxed(~0, cd->gpc_base + GPC_IMR1_CORE0 + i * 4);
258 		writel_relaxed(~0, cd->gpc_base + GPC_IMR1_CORE1 + i * 4);
259 		cd->wakeup_sources[i] = ~0;
260 	}
261 
262 	/* Let CORE0 as the default CPU to wake up by GPC */
263 	cd->cpu2wakeup = GPC_IMR1_CORE0;
264 
265 	/*
266 	 * Due to hardware design failure, need to make sure GPR
267 	 * interrupt(#32) is unmasked during RUN mode to avoid entering
268 	 * DSM by mistake.
269 	 */
270 	writel_relaxed(~0x1, cd->gpc_base + cd->cpu2wakeup);
271 
272 	imx_gpcv2_instance = cd;
273 	register_syscore_ops(&imx_gpcv2_syscore_ops);
274 
275 	return 0;
276 }
277 
278 IRQCHIP_DECLARE(imx_gpcv2, "fsl,imx7d-gpc", imx_gpcv2_irqchip_init);
279