xref: /openbmc/linux/arch/arm/mach-imx/gpc.c (revision ebd09753)
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_CNTR		0x0
24 #define GPC_IMR1		0x008
25 #define GPC_PGC_CPU_PDN		0x2a0
26 #define GPC_PGC_CPU_PUPSCR	0x2a4
27 #define GPC_PGC_CPU_PDNSCR	0x2a8
28 #define GPC_PGC_SW2ISO_SHIFT	0x8
29 #define GPC_PGC_SW_SHIFT	0x0
30 
31 #define GPC_CNTR_L2_PGE_SHIFT	22
32 
33 #define IMR_NUM			4
34 #define GPC_MAX_IRQS		(IMR_NUM * 32)
35 
36 static void __iomem *gpc_base;
37 static u32 gpc_wake_irqs[IMR_NUM];
38 static u32 gpc_saved_imrs[IMR_NUM];
39 
40 void imx_gpc_set_arm_power_up_timing(u32 sw2iso, u32 sw)
41 {
42 	writel_relaxed((sw2iso << GPC_PGC_SW2ISO_SHIFT) |
43 		(sw << GPC_PGC_SW_SHIFT), gpc_base + GPC_PGC_CPU_PUPSCR);
44 }
45 
46 void imx_gpc_set_arm_power_down_timing(u32 sw2iso, u32 sw)
47 {
48 	writel_relaxed((sw2iso << GPC_PGC_SW2ISO_SHIFT) |
49 		(sw << GPC_PGC_SW_SHIFT), gpc_base + GPC_PGC_CPU_PDNSCR);
50 }
51 
52 void imx_gpc_set_arm_power_in_lpm(bool power_off)
53 {
54 	writel_relaxed(power_off, gpc_base + GPC_PGC_CPU_PDN);
55 }
56 
57 void imx_gpc_set_l2_mem_power_in_lpm(bool power_off)
58 {
59 	u32 val;
60 
61 	val = readl_relaxed(gpc_base + GPC_CNTR);
62 	val &= ~(1 << GPC_CNTR_L2_PGE_SHIFT);
63 	if (power_off)
64 		val |= 1 << GPC_CNTR_L2_PGE_SHIFT;
65 	writel_relaxed(val, gpc_base + GPC_CNTR);
66 }
67 
68 void imx_gpc_pre_suspend(bool arm_power_off)
69 {
70 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
71 	int i;
72 
73 	/* Tell GPC to power off ARM core when suspend */
74 	if (arm_power_off)
75 		imx_gpc_set_arm_power_in_lpm(arm_power_off);
76 
77 	for (i = 0; i < IMR_NUM; i++) {
78 		gpc_saved_imrs[i] = readl_relaxed(reg_imr1 + i * 4);
79 		writel_relaxed(~gpc_wake_irqs[i], reg_imr1 + i * 4);
80 	}
81 }
82 
83 void imx_gpc_post_resume(void)
84 {
85 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
86 	int i;
87 
88 	/* Keep ARM core powered on for other low-power modes */
89 	imx_gpc_set_arm_power_in_lpm(false);
90 
91 	for (i = 0; i < IMR_NUM; i++)
92 		writel_relaxed(gpc_saved_imrs[i], reg_imr1 + i * 4);
93 }
94 
95 static int imx_gpc_irq_set_wake(struct irq_data *d, unsigned int on)
96 {
97 	unsigned int idx = d->hwirq / 32;
98 	u32 mask;
99 
100 	mask = 1 << d->hwirq % 32;
101 	gpc_wake_irqs[idx] = on ? gpc_wake_irqs[idx] | mask :
102 				  gpc_wake_irqs[idx] & ~mask;
103 
104 	/*
105 	 * Do *not* call into the parent, as the GIC doesn't have any
106 	 * wake-up facility...
107 	 */
108 	return 0;
109 }
110 
111 void imx_gpc_mask_all(void)
112 {
113 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
114 	int i;
115 
116 	for (i = 0; i < IMR_NUM; i++) {
117 		gpc_saved_imrs[i] = readl_relaxed(reg_imr1 + i * 4);
118 		writel_relaxed(~0, reg_imr1 + i * 4);
119 	}
120 
121 }
122 
123 void imx_gpc_restore_all(void)
124 {
125 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
126 	int i;
127 
128 	for (i = 0; i < IMR_NUM; i++)
129 		writel_relaxed(gpc_saved_imrs[i], reg_imr1 + i * 4);
130 }
131 
132 void imx_gpc_hwirq_unmask(unsigned int hwirq)
133 {
134 	void __iomem *reg;
135 	u32 val;
136 
137 	reg = gpc_base + GPC_IMR1 + hwirq / 32 * 4;
138 	val = readl_relaxed(reg);
139 	val &= ~(1 << hwirq % 32);
140 	writel_relaxed(val, reg);
141 }
142 
143 void imx_gpc_hwirq_mask(unsigned int hwirq)
144 {
145 	void __iomem *reg;
146 	u32 val;
147 
148 	reg = gpc_base + GPC_IMR1 + hwirq / 32 * 4;
149 	val = readl_relaxed(reg);
150 	val |= 1 << (hwirq % 32);
151 	writel_relaxed(val, reg);
152 }
153 
154 static void imx_gpc_irq_unmask(struct irq_data *d)
155 {
156 	imx_gpc_hwirq_unmask(d->hwirq);
157 	irq_chip_unmask_parent(d);
158 }
159 
160 static void imx_gpc_irq_mask(struct irq_data *d)
161 {
162 	imx_gpc_hwirq_mask(d->hwirq);
163 	irq_chip_mask_parent(d);
164 }
165 
166 static struct irq_chip imx_gpc_chip = {
167 	.name			= "GPC",
168 	.irq_eoi		= irq_chip_eoi_parent,
169 	.irq_mask		= imx_gpc_irq_mask,
170 	.irq_unmask		= imx_gpc_irq_unmask,
171 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
172 	.irq_set_wake		= imx_gpc_irq_set_wake,
173 	.irq_set_type           = irq_chip_set_type_parent,
174 #ifdef CONFIG_SMP
175 	.irq_set_affinity	= irq_chip_set_affinity_parent,
176 #endif
177 };
178 
179 static int imx_gpc_domain_translate(struct irq_domain *d,
180 				    struct irq_fwspec *fwspec,
181 				    unsigned long *hwirq,
182 				    unsigned int *type)
183 {
184 	if (is_of_node(fwspec->fwnode)) {
185 		if (fwspec->param_count != 3)
186 			return -EINVAL;
187 
188 		/* No PPI should point to this domain */
189 		if (fwspec->param[0] != 0)
190 			return -EINVAL;
191 
192 		*hwirq = fwspec->param[1];
193 		*type = fwspec->param[2];
194 		return 0;
195 	}
196 
197 	return -EINVAL;
198 }
199 
200 static int imx_gpc_domain_alloc(struct irq_domain *domain,
201 				  unsigned int irq,
202 				  unsigned int nr_irqs, void *data)
203 {
204 	struct irq_fwspec *fwspec = data;
205 	struct irq_fwspec parent_fwspec;
206 	irq_hw_number_t hwirq;
207 	int i;
208 
209 	if (fwspec->param_count != 3)
210 		return -EINVAL;	/* Not GIC compliant */
211 	if (fwspec->param[0] != 0)
212 		return -EINVAL;	/* No PPI should point to this domain */
213 
214 	hwirq = fwspec->param[1];
215 	if (hwirq >= GPC_MAX_IRQS)
216 		return -EINVAL;	/* Can't deal with this */
217 
218 	for (i = 0; i < nr_irqs; i++)
219 		irq_domain_set_hwirq_and_chip(domain, irq + i, hwirq + i,
220 					      &imx_gpc_chip, NULL);
221 
222 	parent_fwspec = *fwspec;
223 	parent_fwspec.fwnode = domain->parent->fwnode;
224 	return irq_domain_alloc_irqs_parent(domain, irq, nr_irqs,
225 					    &parent_fwspec);
226 }
227 
228 static const struct irq_domain_ops imx_gpc_domain_ops = {
229 	.translate	= imx_gpc_domain_translate,
230 	.alloc		= imx_gpc_domain_alloc,
231 	.free		= irq_domain_free_irqs_common,
232 };
233 
234 static int __init imx_gpc_init(struct device_node *node,
235 			       struct device_node *parent)
236 {
237 	struct irq_domain *parent_domain, *domain;
238 	int i;
239 
240 	if (!parent) {
241 		pr_err("%pOF: no parent, giving up\n", node);
242 		return -ENODEV;
243 	}
244 
245 	parent_domain = irq_find_host(parent);
246 	if (!parent_domain) {
247 		pr_err("%pOF: unable to obtain parent domain\n", node);
248 		return -ENXIO;
249 	}
250 
251 	gpc_base = of_iomap(node, 0);
252 	if (WARN_ON(!gpc_base))
253 	        return -ENOMEM;
254 
255 	domain = irq_domain_add_hierarchy(parent_domain, 0, GPC_MAX_IRQS,
256 					  node, &imx_gpc_domain_ops,
257 					  NULL);
258 	if (!domain) {
259 		iounmap(gpc_base);
260 		return -ENOMEM;
261 	}
262 
263 	/* Initially mask all interrupts */
264 	for (i = 0; i < IMR_NUM; i++)
265 		writel_relaxed(~0, gpc_base + GPC_IMR1 + i * 4);
266 
267 	/*
268 	 * Clear the OF_POPULATED flag set in of_irq_init so that
269 	 * later the GPC power domain driver will not be skipped.
270 	 */
271 	of_node_clear_flag(node, OF_POPULATED);
272 
273 	return 0;
274 }
275 IRQCHIP_DECLARE(imx_gpc, "fsl,imx6q-gpc", imx_gpc_init);
276 
277 void __init imx_gpc_check_dt(void)
278 {
279 	struct device_node *np;
280 
281 	np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-gpc");
282 	if (WARN_ON(!np))
283 		return;
284 
285 	if (WARN_ON(!of_find_property(np, "interrupt-controller", NULL))) {
286 		pr_warn("Outdated DT detected, suspend/resume will NOT work\n");
287 
288 		/* map GPC, so that at least CPUidle and WARs keep working */
289 		gpc_base = of_iomap(np, 0);
290 	}
291 }
292