xref: /openbmc/linux/drivers/clk/at91/pmc.c (revision da1d9caf)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
4  */
5 
6 #include <linux/clk.h>
7 #include <linux/clk-provider.h>
8 #include <linux/clkdev.h>
9 #include <linux/clk/at91_pmc.h>
10 #include <linux/of.h>
11 #include <linux/of_address.h>
12 #include <linux/mfd/syscon.h>
13 #include <linux/platform_device.h>
14 #include <linux/regmap.h>
15 #include <linux/syscore_ops.h>
16 
17 #include <asm/proc-fns.h>
18 
19 #include "pmc.h"
20 
21 #define PMC_MAX_IDS 128
22 #define PMC_MAX_PCKS 8
23 
24 int of_at91_get_clk_range(struct device_node *np, const char *propname,
25 			  struct clk_range *range)
26 {
27 	u32 min, max;
28 	int ret;
29 
30 	ret = of_property_read_u32_index(np, propname, 0, &min);
31 	if (ret)
32 		return ret;
33 
34 	ret = of_property_read_u32_index(np, propname, 1, &max);
35 	if (ret)
36 		return ret;
37 
38 	if (range) {
39 		range->min = min;
40 		range->max = max;
41 	}
42 
43 	return 0;
44 }
45 EXPORT_SYMBOL_GPL(of_at91_get_clk_range);
46 
47 struct clk_hw *of_clk_hw_pmc_get(struct of_phandle_args *clkspec, void *data)
48 {
49 	unsigned int type = clkspec->args[0];
50 	unsigned int idx = clkspec->args[1];
51 	struct pmc_data *pmc_data = data;
52 
53 	switch (type) {
54 	case PMC_TYPE_CORE:
55 		if (idx < pmc_data->ncore)
56 			return pmc_data->chws[idx];
57 		break;
58 	case PMC_TYPE_SYSTEM:
59 		if (idx < pmc_data->nsystem)
60 			return pmc_data->shws[idx];
61 		break;
62 	case PMC_TYPE_PERIPHERAL:
63 		if (idx < pmc_data->nperiph)
64 			return pmc_data->phws[idx];
65 		break;
66 	case PMC_TYPE_GCK:
67 		if (idx < pmc_data->ngck)
68 			return pmc_data->ghws[idx];
69 		break;
70 	case PMC_TYPE_PROGRAMMABLE:
71 		if (idx < pmc_data->npck)
72 			return pmc_data->pchws[idx];
73 		break;
74 	default:
75 		break;
76 	}
77 
78 	pr_err("%s: invalid type (%u) or index (%u)\n", __func__, type, idx);
79 
80 	return ERR_PTR(-EINVAL);
81 }
82 
83 struct pmc_data *pmc_data_allocate(unsigned int ncore, unsigned int nsystem,
84 				   unsigned int nperiph, unsigned int ngck,
85 				   unsigned int npck)
86 {
87 	unsigned int num_clks = ncore + nsystem + nperiph + ngck + npck;
88 	struct pmc_data *pmc_data;
89 
90 	pmc_data = kzalloc(struct_size(pmc_data, hwtable, num_clks),
91 			   GFP_KERNEL);
92 	if (!pmc_data)
93 		return NULL;
94 
95 	pmc_data->ncore = ncore;
96 	pmc_data->chws = pmc_data->hwtable;
97 
98 	pmc_data->nsystem = nsystem;
99 	pmc_data->shws = pmc_data->chws + ncore;
100 
101 	pmc_data->nperiph = nperiph;
102 	pmc_data->phws = pmc_data->shws + nsystem;
103 
104 	pmc_data->ngck = ngck;
105 	pmc_data->ghws = pmc_data->phws + nperiph;
106 
107 	pmc_data->npck = npck;
108 	pmc_data->pchws = pmc_data->ghws + ngck;
109 
110 	return pmc_data;
111 }
112 
113 #ifdef CONFIG_PM
114 
115 /* Address in SECURAM that say if we suspend to backup mode. */
116 static void __iomem *at91_pmc_backup_suspend;
117 
118 static int at91_pmc_suspend(void)
119 {
120 	unsigned int backup;
121 
122 	if (!at91_pmc_backup_suspend)
123 		return 0;
124 
125 	backup = readl_relaxed(at91_pmc_backup_suspend);
126 	if (!backup)
127 		return 0;
128 
129 	return clk_save_context();
130 }
131 
132 static void at91_pmc_resume(void)
133 {
134 	unsigned int backup;
135 
136 	if (!at91_pmc_backup_suspend)
137 		return;
138 
139 	backup = readl_relaxed(at91_pmc_backup_suspend);
140 	if (!backup)
141 		return;
142 
143 	clk_restore_context();
144 }
145 
146 static struct syscore_ops pmc_syscore_ops = {
147 	.suspend = at91_pmc_suspend,
148 	.resume = at91_pmc_resume,
149 };
150 
151 static const struct of_device_id pmc_dt_ids[] = {
152 	{ .compatible = "atmel,sama5d2-pmc" },
153 	{ .compatible = "microchip,sama7g5-pmc", },
154 	{ /* sentinel */ }
155 };
156 
157 static int __init pmc_register_ops(void)
158 {
159 	struct device_node *np;
160 
161 	np = of_find_matching_node(NULL, pmc_dt_ids);
162 	if (!np)
163 		return -ENODEV;
164 
165 	if (!of_device_is_available(np)) {
166 		of_node_put(np);
167 		return -ENODEV;
168 	}
169 	of_node_put(np);
170 
171 	np = of_find_compatible_node(NULL, NULL, "atmel,sama5d2-securam");
172 	if (!np)
173 		return -ENODEV;
174 
175 	if (!of_device_is_available(np)) {
176 		of_node_put(np);
177 		return -ENODEV;
178 	}
179 	of_node_put(np);
180 
181 	at91_pmc_backup_suspend = of_iomap(np, 0);
182 	if (!at91_pmc_backup_suspend) {
183 		pr_warn("%s(): unable to map securam\n", __func__);
184 		return -ENOMEM;
185 	}
186 
187 	register_syscore_ops(&pmc_syscore_ops);
188 
189 	return 0;
190 }
191 /* This has to happen before arch_initcall because of the tcb_clksrc driver */
192 postcore_initcall(pmc_register_ops);
193 #endif
194