2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License version 2 as
4 * published by the Free Software Foundation.
6 * This program is distributed in the hope that it will be useful,
7 * but WITHOUT ANY WARRANTY; without even the implied warranty of
8 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
9 * GNU General Public License for more details.
11 * Copyright (C) 2013 ARM Limited
14 #include <linux/amba/sp810.h>
15 #include <linux/slab.h>
16 #include <linux/clk.h>
17 #include <linux/clk-provider.h>
18 #include <linux/err.h>
21 #include <linux/of_address.h>
23 #define to_clk_sp810_timerclken(_hw) \
24 container_of(_hw, struct clk_sp810_timerclken, hw)
28 struct clk_sp810_timerclken {
31 struct clk_sp810 *sp810;
36 struct device_node *node;
39 struct clk_sp810_timerclken timerclken[4];
42 static u8 clk_sp810_timerclken_get_parent(struct clk_hw *hw)
44 struct clk_sp810_timerclken *timerclken = to_clk_sp810_timerclken(hw);
45 u32 val = readl(timerclken->sp810->base + SCCTRL);
47 return !!(val & (1 << SCCTRL_TIMERENnSEL_SHIFT(timerclken->channel)));
50 static int clk_sp810_timerclken_set_parent(struct clk_hw *hw, u8 index)
52 struct clk_sp810_timerclken *timerclken = to_clk_sp810_timerclken(hw);
53 struct clk_sp810 *sp810 = timerclken->sp810;
54 u32 val, shift = SCCTRL_TIMERENnSEL_SHIFT(timerclken->channel);
55 unsigned long flags = 0;
57 if (WARN_ON(index > 1))
60 spin_lock_irqsave(&sp810->lock, flags);
62 val = readl(sp810->base + SCCTRL);
64 val |= index << shift;
65 writel(val, sp810->base + SCCTRL);
67 spin_unlock_irqrestore(&sp810->lock, flags);
72 static const struct clk_ops clk_sp810_timerclken_ops = {
73 .get_parent = clk_sp810_timerclken_get_parent,
74 .set_parent = clk_sp810_timerclken_set_parent,
77 static struct clk *clk_sp810_timerclken_of_get(struct of_phandle_args *clkspec,
80 struct clk_sp810 *sp810 = data;
82 if (WARN_ON(clkspec->args_count != 1 ||
83 clkspec->args[0] >= ARRAY_SIZE(sp810->timerclken)))
86 return sp810->timerclken[clkspec->args[0]].clk;
89 static void __init clk_sp810_of_setup(struct device_node *node)
91 struct clk_sp810 *sp810 = kzalloc(sizeof(*sp810), GFP_KERNEL);
92 const char *parent_names[2];
93 int num = ARRAY_SIZE(parent_names);
95 struct clk_init_data init;
103 if (of_clk_parent_fill(node, parent_names, num) != num) {
104 pr_warn("Failed to obtain parent clocks for SP810!\n");
110 sp810->base = of_iomap(node, 0);
111 spin_lock_init(&sp810->lock);
114 init.ops = &clk_sp810_timerclken_ops;
116 init.parent_names = parent_names;
117 init.num_parents = num;
119 deprecated = !of_find_property(node, "assigned-clock-parents", NULL);
121 for (i = 0; i < ARRAY_SIZE(sp810->timerclken); i++) {
122 snprintf(name, sizeof(name), "sp810_%d_%d", instance, i);
124 sp810->timerclken[i].sp810 = sp810;
125 sp810->timerclken[i].channel = i;
126 sp810->timerclken[i].hw.init = &init;
129 * If DT isn't setting the parent, force it to be
130 * the 1 MHz clock without going through the framework.
131 * We do this before clk_register() so that it can determine
132 * the parent and setup the tree properly.
135 init.ops->set_parent(&sp810->timerclken[i].hw, 1);
137 sp810->timerclken[i].clk = clk_register(NULL,
138 &sp810->timerclken[i].hw);
139 WARN_ON(IS_ERR(sp810->timerclken[i].clk));
142 of_clk_add_provider(node, clk_sp810_timerclken_of_get, sp810);
145 CLK_OF_DECLARE(sp810, "arm,sp810", clk_sp810_of_setup);