xref: /openbmc/linux/arch/arm/mach-imx/gpc.c (revision a44e4f3a)
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 #include <linux/irqchip/arm-gic.h>
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 
117 void imx_gpc_restore_all(void)
118 {
119 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
120 	int i;
121 
122 	for (i = 0; i < IMR_NUM; i++)
123 		writel_relaxed(gpc_saved_imrs[i], reg_imr1 + i * 4);
124 }
125 
126 void imx_gpc_hwirq_unmask(unsigned int hwirq)
127 {
128 	void __iomem *reg;
129 	u32 val;
130 
131 	reg = gpc_base + GPC_IMR1 + hwirq / 32 * 4;
132 	val = readl_relaxed(reg);
133 	val &= ~(1 << hwirq % 32);
134 	writel_relaxed(val, reg);
135 }
136 
137 void imx_gpc_hwirq_mask(unsigned int hwirq)
138 {
139 	void __iomem *reg;
140 	u32 val;
141 
142 	reg = gpc_base + GPC_IMR1 + hwirq / 32 * 4;
143 	val = readl_relaxed(reg);
144 	val |= 1 << (hwirq % 32);
145 	writel_relaxed(val, reg);
146 }
147 
148 static void imx_gpc_irq_unmask(struct irq_data *d)
149 {
150 	imx_gpc_hwirq_unmask(d->hwirq);
151 	irq_chip_unmask_parent(d);
152 }
153 
154 static void imx_gpc_irq_mask(struct irq_data *d)
155 {
156 	imx_gpc_hwirq_mask(d->hwirq);
157 	irq_chip_mask_parent(d);
158 }
159 
160 static struct irq_chip imx_gpc_chip = {
161 	.name			= "GPC",
162 	.irq_eoi		= irq_chip_eoi_parent,
163 	.irq_mask		= imx_gpc_irq_mask,
164 	.irq_unmask		= imx_gpc_irq_unmask,
165 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
166 	.irq_set_wake		= imx_gpc_irq_set_wake,
167 	.irq_set_type           = irq_chip_set_type_parent,
168 #ifdef CONFIG_SMP
169 	.irq_set_affinity	= irq_chip_set_affinity_parent,
170 #endif
171 };
172 
173 static int imx_gpc_domain_translate(struct irq_domain *d,
174 				    struct irq_fwspec *fwspec,
175 				    unsigned long *hwirq,
176 				    unsigned int *type)
177 {
178 	if (is_of_node(fwspec->fwnode)) {
179 		if (fwspec->param_count != 3)
180 			return -EINVAL;
181 
182 		/* No PPI should point to this domain */
183 		if (fwspec->param[0] != 0)
184 			return -EINVAL;
185 
186 		*hwirq = fwspec->param[1];
187 		*type = fwspec->param[2];
188 		return 0;
189 	}
190 
191 	return -EINVAL;
192 }
193 
194 static int imx_gpc_domain_alloc(struct irq_domain *domain,
195 				  unsigned int irq,
196 				  unsigned int nr_irqs, void *data)
197 {
198 	struct irq_fwspec *fwspec = data;
199 	struct irq_fwspec parent_fwspec;
200 	irq_hw_number_t hwirq;
201 	int i;
202 
203 	if (fwspec->param_count != 3)
204 		return -EINVAL;	/* Not GIC compliant */
205 	if (fwspec->param[0] != 0)
206 		return -EINVAL;	/* No PPI should point to this domain */
207 
208 	hwirq = fwspec->param[1];
209 	if (hwirq >= GPC_MAX_IRQS)
210 		return -EINVAL;	/* Can't deal with this */
211 
212 	for (i = 0; i < nr_irqs; i++)
213 		irq_domain_set_hwirq_and_chip(domain, irq + i, hwirq + i,
214 					      &imx_gpc_chip, NULL);
215 
216 	parent_fwspec = *fwspec;
217 	parent_fwspec.fwnode = domain->parent->fwnode;
218 	return irq_domain_alloc_irqs_parent(domain, irq, nr_irqs,
219 					    &parent_fwspec);
220 }
221 
222 static const struct irq_domain_ops imx_gpc_domain_ops = {
223 	.translate	= imx_gpc_domain_translate,
224 	.alloc		= imx_gpc_domain_alloc,
225 	.free		= irq_domain_free_irqs_common,
226 };
227 
228 static int __init imx_gpc_init(struct device_node *node,
229 			       struct device_node *parent)
230 {
231 	struct irq_domain *parent_domain, *domain;
232 	int i;
233 
234 	if (!parent) {
235 		pr_err("%pOF: no parent, giving up\n", node);
236 		return -ENODEV;
237 	}
238 
239 	parent_domain = irq_find_host(parent);
240 	if (!parent_domain) {
241 		pr_err("%pOF: unable to obtain parent domain\n", node);
242 		return -ENXIO;
243 	}
244 
245 	gpc_base = of_iomap(node, 0);
246 	if (WARN_ON(!gpc_base))
247 	        return -ENOMEM;
248 
249 	domain = irq_domain_add_hierarchy(parent_domain, 0, GPC_MAX_IRQS,
250 					  node, &imx_gpc_domain_ops,
251 					  NULL);
252 	if (!domain) {
253 		iounmap(gpc_base);
254 		return -ENOMEM;
255 	}
256 
257 	/* Initially mask all interrupts */
258 	for (i = 0; i < IMR_NUM; i++)
259 		writel_relaxed(~0, gpc_base + GPC_IMR1 + i * 4);
260 
261 	/*
262 	 * Clear the OF_POPULATED flag set in of_irq_init so that
263 	 * later the GPC power domain driver will not be skipped.
264 	 */
265 	of_node_clear_flag(node, OF_POPULATED);
266 
267 	return 0;
268 }
269 IRQCHIP_DECLARE(imx_gpc, "fsl,imx6q-gpc", imx_gpc_init);
270 
271 void __init imx_gpc_check_dt(void)
272 {
273 	struct device_node *np;
274 
275 	np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-gpc");
276 	if (WARN_ON(!np))
277 		return;
278 
279 	if (WARN_ON(!of_find_property(np, "interrupt-controller", NULL))) {
280 		pr_warn("Outdated DT detected, suspend/resume will NOT work\n");
281 
282 		/* map GPC, so that at least CPUidle and WARs keep working */
283 		gpc_base = of_iomap(np, 0);
284 	}
285 }
286