1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * R-Car Gen3 Clock Pulse Generator Library
4  *
5  * Copyright (C) 2015-2018 Glider bvba
6  * Copyright (C) 2019 Renesas Electronics Corp.
7  *
8  * Based on clk-rcar-gen3.c
9  *
10  * Copyright (C) 2015 Renesas Electronics Corp.
11  */
12 
13 #include <linux/clk.h>
14 #include <linux/clk-provider.h>
15 #include <linux/device.h>
16 #include <linux/err.h>
17 #include <linux/init.h>
18 #include <linux/io.h>
19 #include <linux/pm.h>
20 #include <linux/slab.h>
21 #include <linux/sys_soc.h>
22 
23 #include "rcar-cpg-lib.h"
24 
25 spinlock_t cpg_lock;
26 
27 void cpg_reg_modify(void __iomem *reg, u32 clear, u32 set)
28 {
29 	unsigned long flags;
30 	u32 val;
31 
32 	spin_lock_irqsave(&cpg_lock, flags);
33 	val = readl(reg);
34 	val &= ~clear;
35 	val |= set;
36 	writel(val, reg);
37 	spin_unlock_irqrestore(&cpg_lock, flags);
38 };
39 
40 static int cpg_simple_notifier_call(struct notifier_block *nb,
41 				    unsigned long action, void *data)
42 {
43 	struct cpg_simple_notifier *csn =
44 		container_of(nb, struct cpg_simple_notifier, nb);
45 
46 	switch (action) {
47 	case PM_EVENT_SUSPEND:
48 		csn->saved = readl(csn->reg);
49 		return NOTIFY_OK;
50 
51 	case PM_EVENT_RESUME:
52 		writel(csn->saved, csn->reg);
53 		return NOTIFY_OK;
54 	}
55 	return NOTIFY_DONE;
56 }
57 
58 void cpg_simple_notifier_register(struct raw_notifier_head *notifiers,
59 				  struct cpg_simple_notifier *csn)
60 {
61 	csn->nb.notifier_call = cpg_simple_notifier_call;
62 	raw_notifier_chain_register(notifiers, &csn->nb);
63 }
64 
65 /*
66  * SDn Clock
67  */
68 
69 #define SDnSRCFC_SHIFT 2
70 #define STPnHCK	BIT(9 - SDnSRCFC_SHIFT)
71 
72 static const struct clk_div_table cpg_sdh_div_table[] = {
73 	{ 0, 1 }, { 1, 2 }, { STPnHCK | 2, 4 }, { STPnHCK | 3, 8 },
74 	{ STPnHCK | 4, 16 }, { 0, 0 },
75 };
76 
77 struct clk * __init cpg_sdh_clk_register(const char *name,
78 	void __iomem *sdnckcr, const char *parent_name,
79 	struct raw_notifier_head *notifiers)
80 {
81 	struct cpg_simple_notifier *csn;
82 	struct clk *clk;
83 
84 	csn = kzalloc(sizeof(*csn), GFP_KERNEL);
85 	if (!csn)
86 		return ERR_PTR(-ENOMEM);
87 
88 	csn->reg = sdnckcr;
89 
90 	clk = clk_register_divider_table(NULL, name, parent_name, 0, sdnckcr,
91 					 SDnSRCFC_SHIFT, 8, 0, cpg_sdh_div_table,
92 					 &cpg_lock);
93 	if (IS_ERR(clk)) {
94 		kfree(csn);
95 		return clk;
96 	}
97 
98 	cpg_simple_notifier_register(notifiers, csn);
99 	return clk;
100 }
101 
102 static const struct clk_div_table cpg_sd_div_table[] = {
103 	{ 0, 2 }, { 1, 4 }, { 0, 0 },
104 };
105 
106 struct clk * __init cpg_sd_clk_register(const char *name,
107 	void __iomem *sdnckcr, const char *parent_name)
108 {
109 	return clk_register_divider_table(NULL, name, parent_name, 0, sdnckcr,
110 					  0, 2, 0, cpg_sd_div_table, &cpg_lock);
111 }
112 
113 struct rpc_clock {
114 	struct clk_divider div;
115 	struct clk_gate gate;
116 	/*
117 	 * One notifier covers both RPC and RPCD2 clocks as they are both
118 	 * controlled by the same RPCCKCR register...
119 	 */
120 	struct cpg_simple_notifier csn;
121 };
122 
123 static const struct clk_div_table cpg_rpc_div_table[] = {
124 	{ 1, 2 }, { 3, 4 }, { 5, 6 }, { 7, 8 }, { 0, 0 },
125 };
126 
127 struct clk * __init cpg_rpc_clk_register(const char *name,
128 	void __iomem *rpcckcr, const char *parent_name,
129 	struct raw_notifier_head *notifiers)
130 {
131 	struct rpc_clock *rpc;
132 	struct clk *clk;
133 
134 	rpc = kzalloc(sizeof(*rpc), GFP_KERNEL);
135 	if (!rpc)
136 		return ERR_PTR(-ENOMEM);
137 
138 	rpc->div.reg = rpcckcr;
139 	rpc->div.width = 3;
140 	rpc->div.table = cpg_rpc_div_table;
141 	rpc->div.lock = &cpg_lock;
142 
143 	rpc->gate.reg = rpcckcr;
144 	rpc->gate.bit_idx = 8;
145 	rpc->gate.flags = CLK_GATE_SET_TO_DISABLE;
146 	rpc->gate.lock = &cpg_lock;
147 
148 	rpc->csn.reg = rpcckcr;
149 
150 	clk = clk_register_composite(NULL, name, &parent_name, 1, NULL, NULL,
151 				     &rpc->div.hw,  &clk_divider_ops,
152 				     &rpc->gate.hw, &clk_gate_ops,
153 				     CLK_SET_RATE_PARENT);
154 	if (IS_ERR(clk)) {
155 		kfree(rpc);
156 		return clk;
157 	}
158 
159 	cpg_simple_notifier_register(notifiers, &rpc->csn);
160 	return clk;
161 }
162 
163 struct rpcd2_clock {
164 	struct clk_fixed_factor fixed;
165 	struct clk_gate gate;
166 };
167 
168 struct clk * __init cpg_rpcd2_clk_register(const char *name,
169 					   void __iomem *rpcckcr,
170 					   const char *parent_name)
171 {
172 	struct rpcd2_clock *rpcd2;
173 	struct clk *clk;
174 
175 	rpcd2 = kzalloc(sizeof(*rpcd2), GFP_KERNEL);
176 	if (!rpcd2)
177 		return ERR_PTR(-ENOMEM);
178 
179 	rpcd2->fixed.mult = 1;
180 	rpcd2->fixed.div = 2;
181 
182 	rpcd2->gate.reg = rpcckcr;
183 	rpcd2->gate.bit_idx = 9;
184 	rpcd2->gate.flags = CLK_GATE_SET_TO_DISABLE;
185 	rpcd2->gate.lock = &cpg_lock;
186 
187 	clk = clk_register_composite(NULL, name, &parent_name, 1, NULL, NULL,
188 				     &rpcd2->fixed.hw, &clk_fixed_factor_ops,
189 				     &rpcd2->gate.hw, &clk_gate_ops,
190 				     CLK_SET_RATE_PARENT);
191 	if (IS_ERR(clk))
192 		kfree(rpcd2);
193 
194 	return clk;
195 }
196 
197