linux_old1/arch/mips/loongson1/common/clock.c

182 lines
3.2 KiB
C

/*
* Copyright (c) 2011 Zhang, Keguang <keguang.zhang@gmail.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#include <linux/module.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <asm/clock.h>
#include <asm/time.h>
#include <loongson1.h>
static LIST_HEAD(clocks);
static DEFINE_MUTEX(clocks_mutex);
struct clk *clk_get(struct device *dev, const char *name)
{
struct clk *c;
struct clk *ret = NULL;
mutex_lock(&clocks_mutex);
list_for_each_entry(c, &clocks, node) {
if (!strcmp(c->name, name)) {
ret = c;
break;
}
}
mutex_unlock(&clocks_mutex);
return ret;
}
EXPORT_SYMBOL(clk_get);
int clk_enable(struct clk *clk)
{
return 0;
}
EXPORT_SYMBOL(clk_enable);
void clk_disable(struct clk *clk)
{
}
EXPORT_SYMBOL(clk_disable);
unsigned long clk_get_rate(struct clk *clk)
{
return clk->rate;
}
EXPORT_SYMBOL(clk_get_rate);
void clk_put(struct clk *clk)
{
}
EXPORT_SYMBOL(clk_put);
static void pll_clk_init(struct clk *clk)
{
u32 pll;
pll = __raw_readl(LS1X_CLK_PLL_FREQ);
clk->rate = (12 + (pll & 0x3f)) * 33 / 2
+ ((pll >> 8) & 0x3ff) * 33 / 1024 / 2;
clk->rate *= 1000000;
}
static void cpu_clk_init(struct clk *clk)
{
u32 pll, ctrl;
pll = clk_get_rate(clk->parent);
ctrl = __raw_readl(LS1X_CLK_PLL_DIV) & DIV_CPU;
clk->rate = pll / (ctrl >> DIV_CPU_SHIFT);
}
static void ddr_clk_init(struct clk *clk)
{
u32 pll, ctrl;
pll = clk_get_rate(clk->parent);
ctrl = __raw_readl(LS1X_CLK_PLL_DIV) & DIV_DDR;
clk->rate = pll / (ctrl >> DIV_DDR_SHIFT);
}
static void dc_clk_init(struct clk *clk)
{
u32 pll, ctrl;
pll = clk_get_rate(clk->parent);
ctrl = __raw_readl(LS1X_CLK_PLL_DIV) & DIV_DC;
clk->rate = pll / (ctrl >> DIV_DC_SHIFT);
}
static struct clk_ops pll_clk_ops = {
.init = pll_clk_init,
};
static struct clk_ops cpu_clk_ops = {
.init = cpu_clk_init,
};
static struct clk_ops ddr_clk_ops = {
.init = ddr_clk_init,
};
static struct clk_ops dc_clk_ops = {
.init = dc_clk_init,
};
static struct clk pll_clk = {
.name = "pll",
.ops = &pll_clk_ops,
};
static struct clk cpu_clk = {
.name = "cpu",
.parent = &pll_clk,
.ops = &cpu_clk_ops,
};
static struct clk ddr_clk = {
.name = "ddr",
.parent = &pll_clk,
.ops = &ddr_clk_ops,
};
static struct clk dc_clk = {
.name = "dc",
.parent = &pll_clk,
.ops = &dc_clk_ops,
};
int clk_register(struct clk *clk)
{
mutex_lock(&clocks_mutex);
list_add(&clk->node, &clocks);
if (clk->ops->init)
clk->ops->init(clk);
mutex_unlock(&clocks_mutex);
return 0;
}
EXPORT_SYMBOL(clk_register);
static struct clk *ls1x_clks[] = {
&pll_clk,
&cpu_clk,
&ddr_clk,
&dc_clk,
};
int __init ls1x_clock_init(void)
{
int i;
for (i = 0; i < ARRAY_SIZE(ls1x_clks); i++)
clk_register(ls1x_clks[i]);
return 0;
}
void __init plat_time_init(void)
{
struct clk *clk;
/* Initialize LS1X clocks */
ls1x_clock_init();
/* setup mips r4k timer */
clk = clk_get(NULL, "cpu");
if (IS_ERR(clk))
panic("unable to get dc clock, err=%ld", PTR_ERR(clk));
mips_hpt_frequency = clk_get_rate(clk) / 2;
}