xref: /openbmc/linux/arch/arm/mach-imx/gpc.c (revision f7d84fa7)
1 /*
2  * Copyright 2011-2013 Freescale Semiconductor, Inc.
3  * Copyright 2011 Linaro Ltd.
4  *
5  * The code contained herein is licensed under the GNU General Public
6  * License. You may obtain a copy of the GNU General Public License
7  * Version 2 or later at the following locations:
8  *
9  * http://www.opensource.org/licenses/gpl-license.html
10  * http://www.gnu.org/copyleft/gpl.html
11  */
12 
13 #include <linux/io.h>
14 #include <linux/irq.h>
15 #include <linux/irqchip.h>
16 #include <linux/of.h>
17 #include <linux/of_address.h>
18 #include <linux/of_irq.h>
19 #include <linux/irqchip/arm-gic.h>
20 #include "common.h"
21 #include "hardware.h"
22 
23 #define GPC_IMR1		0x008
24 #define GPC_PGC_CPU_PDN		0x2a0
25 #define GPC_PGC_CPU_PUPSCR	0x2a4
26 #define GPC_PGC_CPU_PDNSCR	0x2a8
27 #define GPC_PGC_SW2ISO_SHIFT	0x8
28 #define GPC_PGC_SW_SHIFT	0x0
29 
30 #define IMR_NUM			4
31 #define GPC_MAX_IRQS		(IMR_NUM * 32)
32 
33 static void __iomem *gpc_base;
34 static u32 gpc_wake_irqs[IMR_NUM];
35 static u32 gpc_saved_imrs[IMR_NUM];
36 
37 void imx_gpc_set_arm_power_up_timing(u32 sw2iso, u32 sw)
38 {
39 	writel_relaxed((sw2iso << GPC_PGC_SW2ISO_SHIFT) |
40 		(sw << GPC_PGC_SW_SHIFT), gpc_base + GPC_PGC_CPU_PUPSCR);
41 }
42 
43 void imx_gpc_set_arm_power_down_timing(u32 sw2iso, u32 sw)
44 {
45 	writel_relaxed((sw2iso << GPC_PGC_SW2ISO_SHIFT) |
46 		(sw << GPC_PGC_SW_SHIFT), gpc_base + GPC_PGC_CPU_PDNSCR);
47 }
48 
49 void imx_gpc_set_arm_power_in_lpm(bool power_off)
50 {
51 	writel_relaxed(power_off, gpc_base + GPC_PGC_CPU_PDN);
52 }
53 
54 void imx_gpc_pre_suspend(bool arm_power_off)
55 {
56 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
57 	int i;
58 
59 	/* Tell GPC to power off ARM core when suspend */
60 	if (arm_power_off)
61 		imx_gpc_set_arm_power_in_lpm(arm_power_off);
62 
63 	for (i = 0; i < IMR_NUM; i++) {
64 		gpc_saved_imrs[i] = readl_relaxed(reg_imr1 + i * 4);
65 		writel_relaxed(~gpc_wake_irqs[i], reg_imr1 + i * 4);
66 	}
67 }
68 
69 void imx_gpc_post_resume(void)
70 {
71 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
72 	int i;
73 
74 	/* Keep ARM core powered on for other low-power modes */
75 	imx_gpc_set_arm_power_in_lpm(false);
76 
77 	for (i = 0; i < IMR_NUM; i++)
78 		writel_relaxed(gpc_saved_imrs[i], reg_imr1 + i * 4);
79 }
80 
81 static int imx_gpc_irq_set_wake(struct irq_data *d, unsigned int on)
82 {
83 	unsigned int idx = d->hwirq / 32;
84 	u32 mask;
85 
86 	mask = 1 << d->hwirq % 32;
87 	gpc_wake_irqs[idx] = on ? gpc_wake_irqs[idx] | mask :
88 				  gpc_wake_irqs[idx] & ~mask;
89 
90 	/*
91 	 * Do *not* call into the parent, as the GIC doesn't have any
92 	 * wake-up facility...
93 	 */
94 	return 0;
95 }
96 
97 void imx_gpc_mask_all(void)
98 {
99 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
100 	int i;
101 
102 	for (i = 0; i < IMR_NUM; i++) {
103 		gpc_saved_imrs[i] = readl_relaxed(reg_imr1 + i * 4);
104 		writel_relaxed(~0, reg_imr1 + i * 4);
105 	}
106 
107 }
108 
109 void imx_gpc_restore_all(void)
110 {
111 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
112 	int i;
113 
114 	for (i = 0; i < IMR_NUM; i++)
115 		writel_relaxed(gpc_saved_imrs[i], reg_imr1 + i * 4);
116 }
117 
118 void imx_gpc_hwirq_unmask(unsigned int hwirq)
119 {
120 	void __iomem *reg;
121 	u32 val;
122 
123 	reg = gpc_base + GPC_IMR1 + hwirq / 32 * 4;
124 	val = readl_relaxed(reg);
125 	val &= ~(1 << hwirq % 32);
126 	writel_relaxed(val, reg);
127 }
128 
129 void imx_gpc_hwirq_mask(unsigned int hwirq)
130 {
131 	void __iomem *reg;
132 	u32 val;
133 
134 	reg = gpc_base + GPC_IMR1 + hwirq / 32 * 4;
135 	val = readl_relaxed(reg);
136 	val |= 1 << (hwirq % 32);
137 	writel_relaxed(val, reg);
138 }
139 
140 static void imx_gpc_irq_unmask(struct irq_data *d)
141 {
142 	imx_gpc_hwirq_unmask(d->hwirq);
143 	irq_chip_unmask_parent(d);
144 }
145 
146 static void imx_gpc_irq_mask(struct irq_data *d)
147 {
148 	imx_gpc_hwirq_mask(d->hwirq);
149 	irq_chip_mask_parent(d);
150 }
151 
152 static struct irq_chip imx_gpc_chip = {
153 	.name			= "GPC",
154 	.irq_eoi		= irq_chip_eoi_parent,
155 	.irq_mask		= imx_gpc_irq_mask,
156 	.irq_unmask		= imx_gpc_irq_unmask,
157 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
158 	.irq_set_wake		= imx_gpc_irq_set_wake,
159 	.irq_set_type           = irq_chip_set_type_parent,
160 #ifdef CONFIG_SMP
161 	.irq_set_affinity	= irq_chip_set_affinity_parent,
162 #endif
163 };
164 
165 static int imx_gpc_domain_translate(struct irq_domain *d,
166 				    struct irq_fwspec *fwspec,
167 				    unsigned long *hwirq,
168 				    unsigned int *type)
169 {
170 	if (is_of_node(fwspec->fwnode)) {
171 		if (fwspec->param_count != 3)
172 			return -EINVAL;
173 
174 		/* No PPI should point to this domain */
175 		if (fwspec->param[0] != 0)
176 			return -EINVAL;
177 
178 		*hwirq = fwspec->param[1];
179 		*type = fwspec->param[2];
180 		return 0;
181 	}
182 
183 	return -EINVAL;
184 }
185 
186 static int imx_gpc_domain_alloc(struct irq_domain *domain,
187 				  unsigned int irq,
188 				  unsigned int nr_irqs, void *data)
189 {
190 	struct irq_fwspec *fwspec = data;
191 	struct irq_fwspec parent_fwspec;
192 	irq_hw_number_t hwirq;
193 	int i;
194 
195 	if (fwspec->param_count != 3)
196 		return -EINVAL;	/* Not GIC compliant */
197 	if (fwspec->param[0] != 0)
198 		return -EINVAL;	/* No PPI should point to this domain */
199 
200 	hwirq = fwspec->param[1];
201 	if (hwirq >= GPC_MAX_IRQS)
202 		return -EINVAL;	/* Can't deal with this */
203 
204 	for (i = 0; i < nr_irqs; i++)
205 		irq_domain_set_hwirq_and_chip(domain, irq + i, hwirq + i,
206 					      &imx_gpc_chip, NULL);
207 
208 	parent_fwspec = *fwspec;
209 	parent_fwspec.fwnode = domain->parent->fwnode;
210 	return irq_domain_alloc_irqs_parent(domain, irq, nr_irqs,
211 					    &parent_fwspec);
212 }
213 
214 static const struct irq_domain_ops imx_gpc_domain_ops = {
215 	.translate	= imx_gpc_domain_translate,
216 	.alloc		= imx_gpc_domain_alloc,
217 	.free		= irq_domain_free_irqs_common,
218 };
219 
220 static int __init imx_gpc_init(struct device_node *node,
221 			       struct device_node *parent)
222 {
223 	struct irq_domain *parent_domain, *domain;
224 	int i;
225 
226 	if (!parent) {
227 		pr_err("%s: no parent, giving up\n", node->full_name);
228 		return -ENODEV;
229 	}
230 
231 	parent_domain = irq_find_host(parent);
232 	if (!parent_domain) {
233 		pr_err("%s: unable to obtain parent domain\n", node->full_name);
234 		return -ENXIO;
235 	}
236 
237 	gpc_base = of_iomap(node, 0);
238 	if (WARN_ON(!gpc_base))
239 	        return -ENOMEM;
240 
241 	domain = irq_domain_add_hierarchy(parent_domain, 0, GPC_MAX_IRQS,
242 					  node, &imx_gpc_domain_ops,
243 					  NULL);
244 	if (!domain) {
245 		iounmap(gpc_base);
246 		return -ENOMEM;
247 	}
248 
249 	/* Initially mask all interrupts */
250 	for (i = 0; i < IMR_NUM; i++)
251 		writel_relaxed(~0, gpc_base + GPC_IMR1 + i * 4);
252 
253 	/*
254 	 * Clear the OF_POPULATED flag set in of_irq_init so that
255 	 * later the GPC power domain driver will not be skipped.
256 	 */
257 	of_node_clear_flag(node, OF_POPULATED);
258 
259 	return 0;
260 }
261 IRQCHIP_DECLARE(imx_gpc, "fsl,imx6q-gpc", imx_gpc_init);
262 
263 void __init imx_gpc_check_dt(void)
264 {
265 	struct device_node *np;
266 
267 	np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-gpc");
268 	if (WARN_ON(!np))
269 		return;
270 
271 	if (WARN_ON(!of_find_property(np, "interrupt-controller", NULL))) {
272 		pr_warn("Outdated DT detected, suspend/resume will NOT work\n");
273 
274 		/* map GPC, so that at least CPUidle and WARs keep working */
275 		gpc_base = of_iomap(np, 0);
276 	}
277 }
278