| /* |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * Copyright (C) 2013 ARM Limited |
| */ |
| |
| #include <linux/amba/sp810.h> |
| #include <linux/slab.h> |
| #include <linux/clk.h> |
| #include <linux/clk-provider.h> |
| #include <linux/err.h> |
| #include <linux/of.h> |
| #include <linux/of_address.h> |
| |
| #define to_clk_sp810_timerclken(_hw) \ |
| container_of(_hw, struct clk_sp810_timerclken, hw) |
| |
| struct clk_sp810; |
| |
| struct clk_sp810_timerclken { |
| struct clk_hw hw; |
| struct clk *clk; |
| struct clk_sp810 *sp810; |
| int channel; |
| }; |
| |
| struct clk_sp810 { |
| struct device_node *node; |
| void __iomem *base; |
| spinlock_t lock; |
| struct clk_sp810_timerclken timerclken[4]; |
| }; |
| |
| static u8 clk_sp810_timerclken_get_parent(struct clk_hw *hw) |
| { |
| struct clk_sp810_timerclken *timerclken = to_clk_sp810_timerclken(hw); |
| u32 val = readl(timerclken->sp810->base + SCCTRL); |
| |
| return !!(val & (1 << SCCTRL_TIMERENnSEL_SHIFT(timerclken->channel))); |
| } |
| |
| static int clk_sp810_timerclken_set_parent(struct clk_hw *hw, u8 index) |
| { |
| struct clk_sp810_timerclken *timerclken = to_clk_sp810_timerclken(hw); |
| struct clk_sp810 *sp810 = timerclken->sp810; |
| u32 val, shift = SCCTRL_TIMERENnSEL_SHIFT(timerclken->channel); |
| unsigned long flags = 0; |
| |
| if (WARN_ON(index > 1)) |
| return -EINVAL; |
| |
| spin_lock_irqsave(&sp810->lock, flags); |
| |
| val = readl(sp810->base + SCCTRL); |
| val &= ~(1 << shift); |
| val |= index << shift; |
| writel(val, sp810->base + SCCTRL); |
| |
| spin_unlock_irqrestore(&sp810->lock, flags); |
| |
| return 0; |
| } |
| |
| static const struct clk_ops clk_sp810_timerclken_ops = { |
| .get_parent = clk_sp810_timerclken_get_parent, |
| .set_parent = clk_sp810_timerclken_set_parent, |
| }; |
| |
| static struct clk *clk_sp810_timerclken_of_get(struct of_phandle_args *clkspec, |
| void *data) |
| { |
| struct clk_sp810 *sp810 = data; |
| |
| if (WARN_ON(clkspec->args_count != 1 || |
| clkspec->args[0] >= ARRAY_SIZE(sp810->timerclken))) |
| return NULL; |
| |
| return sp810->timerclken[clkspec->args[0]].clk; |
| } |
| |
| static void __init clk_sp810_of_setup(struct device_node *node) |
| { |
| struct clk_sp810 *sp810 = kzalloc(sizeof(*sp810), GFP_KERNEL); |
| const char *parent_names[2]; |
| int num = ARRAY_SIZE(parent_names); |
| char name[12]; |
| struct clk_init_data init; |
| int i; |
| bool deprecated; |
| |
| if (!sp810) |
| return; |
| |
| if (of_clk_parent_fill(node, parent_names, num) != num) { |
| pr_warn("Failed to obtain parent clocks for SP810!\n"); |
| kfree(sp810); |
| return; |
| } |
| |
| sp810->node = node; |
| sp810->base = of_iomap(node, 0); |
| spin_lock_init(&sp810->lock); |
| |
| init.name = name; |
| init.ops = &clk_sp810_timerclken_ops; |
| init.flags = CLK_IS_BASIC; |
| init.parent_names = parent_names; |
| init.num_parents = num; |
| |
| deprecated = !of_find_property(node, "assigned-clock-parents", NULL); |
| |
| for (i = 0; i < ARRAY_SIZE(sp810->timerclken); i++) { |
| snprintf(name, ARRAY_SIZE(name), "timerclken%d", i); |
| |
| sp810->timerclken[i].sp810 = sp810; |
| sp810->timerclken[i].channel = i; |
| sp810->timerclken[i].hw.init = &init; |
| |
| /* |
| * If DT isn't setting the parent, force it to be |
| * the 1 MHz clock without going through the framework. |
| * We do this before clk_register() so that it can determine |
| * the parent and setup the tree properly. |
| */ |
| if (deprecated) |
| init.ops->set_parent(&sp810->timerclken[i].hw, 1); |
| |
| sp810->timerclken[i].clk = clk_register(NULL, |
| &sp810->timerclken[i].hw); |
| WARN_ON(IS_ERR(sp810->timerclken[i].clk)); |
| } |
| |
| of_clk_add_provider(node, clk_sp810_timerclken_of_get, sp810); |
| } |
| CLK_OF_DECLARE(sp810, "arm,sp810", clk_sp810_of_setup); |