xref: /linux/drivers/irqchip/irq-imx-gpcv2.c (revision 2b4f44eec2be2688511c2b617d0e1b4f94c45ba4)
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 static int gpcv2_wakeup_source_save(void)
32 {
33 	struct gpcv2_irqchip_data *cd;
34 	void __iomem *reg;
35 	int i;
36 
37 	cd = imx_gpcv2_instance;
38 	if (!cd)
39 		return 0;
40 
41 	for (i = 0; i < IMR_NUM; i++) {
42 		reg = cd->gpc_base + cd->cpu2wakeup + i * 4;
43 		cd->saved_irq_mask[i] = readl_relaxed(reg);
44 		writel_relaxed(cd->wakeup_sources[i], reg);
45 	}
46 
47 	return 0;
48 }
49 
50 static void gpcv2_wakeup_source_restore(void)
51 {
52 	struct gpcv2_irqchip_data *cd;
53 	void __iomem *reg;
54 	int i;
55 
56 	cd = imx_gpcv2_instance;
57 	if (!cd)
58 		return;
59 
60 	for (i = 0; i < IMR_NUM; i++) {
61 		reg = cd->gpc_base + cd->cpu2wakeup + i * 4;
62 		writel_relaxed(cd->saved_irq_mask[i], reg);
63 	}
64 }
65 
66 static struct syscore_ops imx_gpcv2_syscore_ops = {
67 	.suspend	= gpcv2_wakeup_source_save,
68 	.resume		= gpcv2_wakeup_source_restore,
69 };
70 
71 static int imx_gpcv2_irq_set_wake(struct irq_data *d, unsigned int on)
72 {
73 	struct gpcv2_irqchip_data *cd = d->chip_data;
74 	unsigned int idx = d->hwirq / 32;
75 	unsigned long flags;
76 	void __iomem *reg;
77 	u32 mask, val;
78 
79 	raw_spin_lock_irqsave(&cd->rlock, flags);
80 	reg = cd->gpc_base + cd->cpu2wakeup + idx * 4;
81 	mask = 1 << d->hwirq % 32;
82 	val = cd->wakeup_sources[idx];
83 
84 	cd->wakeup_sources[idx] = on ? (val & ~mask) : (val | mask);
85 	raw_spin_unlock_irqrestore(&cd->rlock, flags);
86 
87 	/*
88 	 * Do *not* call into the parent, as the GIC doesn't have any
89 	 * wake-up facility...
90 	 */
91 
92 	return 0;
93 }
94 
95 static void imx_gpcv2_irq_unmask(struct irq_data *d)
96 {
97 	struct gpcv2_irqchip_data *cd = d->chip_data;
98 	void __iomem *reg;
99 	u32 val;
100 
101 	raw_spin_lock(&cd->rlock);
102 	reg = cd->gpc_base + cd->cpu2wakeup + d->hwirq / 32 * 4;
103 	val = readl_relaxed(reg);
104 	val &= ~(1 << d->hwirq % 32);
105 	writel_relaxed(val, reg);
106 	raw_spin_unlock(&cd->rlock);
107 
108 	irq_chip_unmask_parent(d);
109 }
110 
111 static void imx_gpcv2_irq_mask(struct irq_data *d)
112 {
113 	struct gpcv2_irqchip_data *cd = d->chip_data;
114 	void __iomem *reg;
115 	u32 val;
116 
117 	raw_spin_lock(&cd->rlock);
118 	reg = cd->gpc_base + cd->cpu2wakeup + d->hwirq / 32 * 4;
119 	val = readl_relaxed(reg);
120 	val |= 1 << (d->hwirq % 32);
121 	writel_relaxed(val, reg);
122 	raw_spin_unlock(&cd->rlock);
123 
124 	irq_chip_mask_parent(d);
125 }
126 
127 static struct irq_chip gpcv2_irqchip_data_chip = {
128 	.name			= "GPCv2",
129 	.irq_eoi		= irq_chip_eoi_parent,
130 	.irq_mask		= imx_gpcv2_irq_mask,
131 	.irq_unmask		= imx_gpcv2_irq_unmask,
132 	.irq_set_wake		= imx_gpcv2_irq_set_wake,
133 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
134 #ifdef CONFIG_SMP
135 	.irq_set_affinity	= irq_chip_set_affinity_parent,
136 #endif
137 };
138 
139 static int imx_gpcv2_domain_translate(struct irq_domain *d,
140 				      struct irq_fwspec *fwspec,
141 				      unsigned long *hwirq,
142 				      unsigned int *type)
143 {
144 	if (is_of_node(fwspec->fwnode)) {
145 		if (fwspec->param_count != 3)
146 			return -EINVAL;
147 
148 		/* No PPI should point to this domain */
149 		if (fwspec->param[0] != 0)
150 			return -EINVAL;
151 
152 		*hwirq = fwspec->param[1];
153 		*type = fwspec->param[2];
154 		return 0;
155 	}
156 
157 	return -EINVAL;
158 }
159 
160 static int imx_gpcv2_domain_alloc(struct irq_domain *domain,
161 				  unsigned int irq, unsigned int nr_irqs,
162 				  void *data)
163 {
164 	struct irq_fwspec *fwspec = data;
165 	struct irq_fwspec parent_fwspec;
166 	irq_hw_number_t hwirq;
167 	unsigned int type;
168 	int err;
169 	int i;
170 
171 	err = imx_gpcv2_domain_translate(domain, fwspec, &hwirq, &type);
172 	if (err)
173 		return err;
174 
175 	if (hwirq >= GPC_MAX_IRQS)
176 		return -EINVAL;
177 
178 	for (i = 0; i < nr_irqs; i++) {
179 		irq_domain_set_hwirq_and_chip(domain, irq + i, hwirq + i,
180 				&gpcv2_irqchip_data_chip, domain->host_data);
181 	}
182 
183 	parent_fwspec = *fwspec;
184 	parent_fwspec.fwnode = domain->parent->fwnode;
185 	return irq_domain_alloc_irqs_parent(domain, irq, nr_irqs,
186 					    &parent_fwspec);
187 }
188 
189 static const struct irq_domain_ops gpcv2_irqchip_data_domain_ops = {
190 	.translate	= imx_gpcv2_domain_translate,
191 	.alloc		= imx_gpcv2_domain_alloc,
192 	.free		= irq_domain_free_irqs_common,
193 };
194 
195 static int __init imx_gpcv2_irqchip_init(struct device_node *node,
196 			       struct device_node *parent)
197 {
198 	struct irq_domain *parent_domain, *domain;
199 	struct gpcv2_irqchip_data *cd;
200 	int i;
201 
202 	if (!parent) {
203 		pr_err("%pOF: no parent, giving up\n", node);
204 		return -ENODEV;
205 	}
206 
207 	parent_domain = irq_find_host(parent);
208 	if (!parent_domain) {
209 		pr_err("%pOF: unable to get parent domain\n", node);
210 		return -ENXIO;
211 	}
212 
213 	cd = kzalloc(sizeof(struct gpcv2_irqchip_data), GFP_KERNEL);
214 	if (!cd) {
215 		pr_err("kzalloc failed!\n");
216 		return -ENOMEM;
217 	}
218 
219 	raw_spin_lock_init(&cd->rlock);
220 
221 	cd->gpc_base = of_iomap(node, 0);
222 	if (!cd->gpc_base) {
223 		pr_err("fsl-gpcv2: unable to map gpc registers\n");
224 		kfree(cd);
225 		return -ENOMEM;
226 	}
227 
228 	domain = irq_domain_add_hierarchy(parent_domain, 0, GPC_MAX_IRQS,
229 				node, &gpcv2_irqchip_data_domain_ops, cd);
230 	if (!domain) {
231 		iounmap(cd->gpc_base);
232 		kfree(cd);
233 		return -ENOMEM;
234 	}
235 	irq_set_default_host(domain);
236 
237 	/* Initially mask all interrupts */
238 	for (i = 0; i < IMR_NUM; i++) {
239 		writel_relaxed(~0, cd->gpc_base + GPC_IMR1_CORE0 + i * 4);
240 		writel_relaxed(~0, cd->gpc_base + GPC_IMR1_CORE1 + i * 4);
241 		cd->wakeup_sources[i] = ~0;
242 	}
243 
244 	/* Let CORE0 as the default CPU to wake up by GPC */
245 	cd->cpu2wakeup = GPC_IMR1_CORE0;
246 
247 	/*
248 	 * Due to hardware design failure, need to make sure GPR
249 	 * interrupt(#32) is unmasked during RUN mode to avoid entering
250 	 * DSM by mistake.
251 	 */
252 	writel_relaxed(~0x1, cd->gpc_base + cd->cpu2wakeup);
253 
254 	imx_gpcv2_instance = cd;
255 	register_syscore_ops(&imx_gpcv2_syscore_ops);
256 
257 	/*
258 	 * Clear the OF_POPULATED flag set in of_irq_init so that
259 	 * later the GPC power domain driver will not be skipped.
260 	 */
261 	of_node_clear_flag(node, OF_POPULATED);
262 	return 0;
263 }
264 
265 IRQCHIP_DECLARE(imx_gpcv2, "fsl,imx7d-gpc", imx_gpcv2_irqchip_init);
266