xref: /openbmc/linux/drivers/clk/mmp/clk-apmu.c (revision dff03381)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * mmp AXI peripharal clock operation source file
4  *
5  * Copyright (C) 2012 Marvell
6  * Chao Xie <xiechao.mail@gmail.com>
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/io.h>
11 #include <linux/err.h>
12 #include <linux/delay.h>
13 #include <linux/slab.h>
14 
15 #include "clk.h"
16 
17 #define to_clk_apmu(clk) (container_of(clk, struct clk_apmu, clk))
18 struct clk_apmu {
19 	struct clk_hw   hw;
20 	void __iomem    *base;
21 	u32		rst_mask;
22 	u32		enable_mask;
23 	spinlock_t	*lock;
24 };
25 
26 static int clk_apmu_enable(struct clk_hw *hw)
27 {
28 	struct clk_apmu *apmu = to_clk_apmu(hw);
29 	unsigned long data;
30 	unsigned long flags = 0;
31 
32 	if (apmu->lock)
33 		spin_lock_irqsave(apmu->lock, flags);
34 
35 	data = readl_relaxed(apmu->base) | apmu->enable_mask;
36 	writel_relaxed(data, apmu->base);
37 
38 	if (apmu->lock)
39 		spin_unlock_irqrestore(apmu->lock, flags);
40 
41 	return 0;
42 }
43 
44 static void clk_apmu_disable(struct clk_hw *hw)
45 {
46 	struct clk_apmu *apmu = to_clk_apmu(hw);
47 	unsigned long data;
48 	unsigned long flags = 0;
49 
50 	if (apmu->lock)
51 		spin_lock_irqsave(apmu->lock, flags);
52 
53 	data = readl_relaxed(apmu->base) & ~apmu->enable_mask;
54 	writel_relaxed(data, apmu->base);
55 
56 	if (apmu->lock)
57 		spin_unlock_irqrestore(apmu->lock, flags);
58 }
59 
60 static const struct clk_ops clk_apmu_ops = {
61 	.enable = clk_apmu_enable,
62 	.disable = clk_apmu_disable,
63 };
64 
65 struct clk *mmp_clk_register_apmu(const char *name, const char *parent_name,
66 		void __iomem *base, u32 enable_mask, spinlock_t *lock)
67 {
68 	struct clk_apmu *apmu;
69 	struct clk *clk;
70 	struct clk_init_data init;
71 
72 	apmu = kzalloc(sizeof(*apmu), GFP_KERNEL);
73 	if (!apmu)
74 		return NULL;
75 
76 	init.name = name;
77 	init.ops = &clk_apmu_ops;
78 	init.flags = CLK_SET_RATE_PARENT;
79 	init.parent_names = (parent_name ? &parent_name : NULL);
80 	init.num_parents = (parent_name ? 1 : 0);
81 
82 	apmu->base = base;
83 	apmu->enable_mask = enable_mask;
84 	apmu->lock = lock;
85 	apmu->hw.init = &init;
86 
87 	clk = clk_register(NULL, &apmu->hw);
88 
89 	if (IS_ERR(clk))
90 		kfree(apmu);
91 
92 	return clk;
93 }
94