xref: /openbmc/linux/arch/arm/mach-imx/gpc.c (revision bbaf1ff0)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright 2011-2013 Freescale Semiconductor, Inc.
4  * Copyright 2011 Linaro Ltd.
5  */
6 
7 #include <linux/io.h>
8 #include <linux/irq.h>
9 #include <linux/irqchip.h>
10 #include <linux/of.h>
11 #include <linux/of_address.h>
12 #include <linux/of_irq.h>
13 
14 #include "common.h"
15 #include "hardware.h"
16 
17 #define GPC_CNTR		0x0
18 #define GPC_IMR1		0x008
19 #define GPC_PGC_CPU_PDN		0x2a0
20 #define GPC_PGC_CPU_PUPSCR	0x2a4
21 #define GPC_PGC_CPU_PDNSCR	0x2a8
22 #define GPC_PGC_SW2ISO_SHIFT	0x8
23 #define GPC_PGC_SW_SHIFT	0x0
24 
25 #define GPC_CNTR_L2_PGE_SHIFT	22
26 
27 #define IMR_NUM			4
28 #define GPC_MAX_IRQS		(IMR_NUM * 32)
29 
30 static void __iomem *gpc_base;
31 static u32 gpc_wake_irqs[IMR_NUM];
32 static u32 gpc_saved_imrs[IMR_NUM];
33 
34 void imx_gpc_set_arm_power_up_timing(u32 sw2iso, u32 sw)
35 {
36 	writel_relaxed((sw2iso << GPC_PGC_SW2ISO_SHIFT) |
37 		(sw << GPC_PGC_SW_SHIFT), gpc_base + GPC_PGC_CPU_PUPSCR);
38 }
39 
40 void imx_gpc_set_arm_power_down_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_PDNSCR);
44 }
45 
46 void imx_gpc_set_arm_power_in_lpm(bool power_off)
47 {
48 	writel_relaxed(power_off, gpc_base + GPC_PGC_CPU_PDN);
49 }
50 
51 void imx_gpc_set_l2_mem_power_in_lpm(bool power_off)
52 {
53 	u32 val;
54 
55 	val = readl_relaxed(gpc_base + GPC_CNTR);
56 	val &= ~(1 << GPC_CNTR_L2_PGE_SHIFT);
57 	if (power_off)
58 		val |= 1 << GPC_CNTR_L2_PGE_SHIFT;
59 	writel_relaxed(val, gpc_base + GPC_CNTR);
60 }
61 
62 void imx_gpc_pre_suspend(bool arm_power_off)
63 {
64 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
65 	int i;
66 
67 	/* Tell GPC to power off ARM core when suspend */
68 	if (arm_power_off)
69 		imx_gpc_set_arm_power_in_lpm(arm_power_off);
70 
71 	for (i = 0; i < IMR_NUM; i++) {
72 		gpc_saved_imrs[i] = readl_relaxed(reg_imr1 + i * 4);
73 		writel_relaxed(~gpc_wake_irqs[i], reg_imr1 + i * 4);
74 	}
75 }
76 
77 void imx_gpc_post_resume(void)
78 {
79 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
80 	int i;
81 
82 	/* Keep ARM core powered on for other low-power modes */
83 	imx_gpc_set_arm_power_in_lpm(false);
84 
85 	for (i = 0; i < IMR_NUM; i++)
86 		writel_relaxed(gpc_saved_imrs[i], reg_imr1 + i * 4);
87 }
88 
89 static int imx_gpc_irq_set_wake(struct irq_data *d, unsigned int on)
90 {
91 	unsigned int idx = d->hwirq / 32;
92 	u32 mask;
93 
94 	mask = 1 << d->hwirq % 32;
95 	gpc_wake_irqs[idx] = on ? gpc_wake_irqs[idx] | mask :
96 				  gpc_wake_irqs[idx] & ~mask;
97 
98 	/*
99 	 * Do *not* call into the parent, as the GIC doesn't have any
100 	 * wake-up facility...
101 	 */
102 	return 0;
103 }
104 
105 void imx_gpc_mask_all(void)
106 {
107 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
108 	int i;
109 
110 	for (i = 0; i < IMR_NUM; i++) {
111 		gpc_saved_imrs[i] = readl_relaxed(reg_imr1 + i * 4);
112 		writel_relaxed(~0, reg_imr1 + i * 4);
113 	}
114 }
115 
116 void imx_gpc_restore_all(void)
117 {
118 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
119 	int i;
120 
121 	for (i = 0; i < IMR_NUM; i++)
122 		writel_relaxed(gpc_saved_imrs[i], reg_imr1 + i * 4);
123 }
124 
125 void imx_gpc_hwirq_unmask(unsigned int hwirq)
126 {
127 	void __iomem *reg;
128 	u32 val;
129 
130 	reg = gpc_base + GPC_IMR1 + hwirq / 32 * 4;
131 	val = readl_relaxed(reg);
132 	val &= ~(1 << hwirq % 32);
133 	writel_relaxed(val, reg);
134 }
135 
136 void imx_gpc_hwirq_mask(unsigned int hwirq)
137 {
138 	void __iomem *reg;
139 	u32 val;
140 
141 	reg = gpc_base + GPC_IMR1 + hwirq / 32 * 4;
142 	val = readl_relaxed(reg);
143 	val |= 1 << (hwirq % 32);
144 	writel_relaxed(val, reg);
145 }
146 
147 static void imx_gpc_irq_unmask(struct irq_data *d)
148 {
149 	imx_gpc_hwirq_unmask(d->hwirq);
150 	irq_chip_unmask_parent(d);
151 }
152 
153 static void imx_gpc_irq_mask(struct irq_data *d)
154 {
155 	imx_gpc_hwirq_mask(d->hwirq);
156 	irq_chip_mask_parent(d);
157 }
158 
159 static struct irq_chip imx_gpc_chip = {
160 	.name			= "GPC",
161 	.irq_eoi		= irq_chip_eoi_parent,
162 	.irq_mask		= imx_gpc_irq_mask,
163 	.irq_unmask		= imx_gpc_irq_unmask,
164 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
165 	.irq_set_wake		= imx_gpc_irq_set_wake,
166 	.irq_set_type           = irq_chip_set_type_parent,
167 #ifdef CONFIG_SMP
168 	.irq_set_affinity	= irq_chip_set_affinity_parent,
169 #endif
170 };
171 
172 static int imx_gpc_domain_translate(struct irq_domain *d,
173 				    struct irq_fwspec *fwspec,
174 				    unsigned long *hwirq,
175 				    unsigned int *type)
176 {
177 	if (is_of_node(fwspec->fwnode)) {
178 		if (fwspec->param_count != 3)
179 			return -EINVAL;
180 
181 		/* No PPI should point to this domain */
182 		if (fwspec->param[0] != 0)
183 			return -EINVAL;
184 
185 		*hwirq = fwspec->param[1];
186 		*type = fwspec->param[2];
187 		return 0;
188 	}
189 
190 	return -EINVAL;
191 }
192 
193 static int imx_gpc_domain_alloc(struct irq_domain *domain,
194 				  unsigned int irq,
195 				  unsigned int nr_irqs, void *data)
196 {
197 	struct irq_fwspec *fwspec = data;
198 	struct irq_fwspec parent_fwspec;
199 	irq_hw_number_t hwirq;
200 	int i;
201 
202 	if (fwspec->param_count != 3)
203 		return -EINVAL;	/* Not GIC compliant */
204 	if (fwspec->param[0] != 0)
205 		return -EINVAL;	/* No PPI should point to this domain */
206 
207 	hwirq = fwspec->param[1];
208 	if (hwirq >= GPC_MAX_IRQS)
209 		return -EINVAL;	/* Can't deal with this */
210 
211 	for (i = 0; i < nr_irqs; i++)
212 		irq_domain_set_hwirq_and_chip(domain, irq + i, hwirq + i,
213 					      &imx_gpc_chip, NULL);
214 
215 	parent_fwspec = *fwspec;
216 	parent_fwspec.fwnode = domain->parent->fwnode;
217 	return irq_domain_alloc_irqs_parent(domain, irq, nr_irqs,
218 					    &parent_fwspec);
219 }
220 
221 static const struct irq_domain_ops imx_gpc_domain_ops = {
222 	.translate	= imx_gpc_domain_translate,
223 	.alloc		= imx_gpc_domain_alloc,
224 	.free		= irq_domain_free_irqs_common,
225 };
226 
227 static int __init imx_gpc_init(struct device_node *node,
228 			       struct device_node *parent)
229 {
230 	struct irq_domain *parent_domain, *domain;
231 	int i;
232 
233 	if (!parent) {
234 		pr_err("%pOF: no parent, giving up\n", node);
235 		return -ENODEV;
236 	}
237 
238 	parent_domain = irq_find_host(parent);
239 	if (!parent_domain) {
240 		pr_err("%pOF: unable to obtain parent domain\n", node);
241 		return -ENXIO;
242 	}
243 
244 	gpc_base = of_iomap(node, 0);
245 	if (WARN_ON(!gpc_base))
246 	        return -ENOMEM;
247 
248 	domain = irq_domain_add_hierarchy(parent_domain, 0, GPC_MAX_IRQS,
249 					  node, &imx_gpc_domain_ops,
250 					  NULL);
251 	if (!domain) {
252 		iounmap(gpc_base);
253 		return -ENOMEM;
254 	}
255 
256 	/* Initially mask all interrupts */
257 	for (i = 0; i < IMR_NUM; i++)
258 		writel_relaxed(~0, gpc_base + GPC_IMR1 + i * 4);
259 
260 	/*
261 	 * Clear the OF_POPULATED flag set in of_irq_init so that
262 	 * later the GPC power domain driver will not be skipped.
263 	 */
264 	of_node_clear_flag(node, OF_POPULATED);
265 
266 	return 0;
267 }
268 IRQCHIP_DECLARE(imx_gpc, "fsl,imx6q-gpc", imx_gpc_init);
269 
270 void __init imx_gpc_check_dt(void)
271 {
272 	struct device_node *np;
273 
274 	np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-gpc");
275 	if (WARN_ON(!np))
276 		return;
277 
278 	if (WARN_ON(!of_property_read_bool(np, "interrupt-controller"))) {
279 		pr_warn("Outdated DT detected, suspend/resume will NOT work\n");
280 
281 		/* map GPC, so that at least CPUidle and WARs keep working */
282 		gpc_base = of_iomap(np, 0);
283 	}
284 	of_node_put(np);
285 }
286