145 lines
3.8 KiB
C
145 lines
3.8 KiB
C
/*
|
|
* 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;
|
|
static int instance;
|
|
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, sizeof(name), "sp810_%d_%d", instance, 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);
|
|
instance++;
|
|
}
|
|
CLK_OF_DECLARE(sp810, "arm,sp810", clk_sp810_of_setup);
|