linux-sg2042/drivers/clk/clk-ls1x.c

112 lines
2.8 KiB
C

/*
* Copyright (c) 2012 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/clkdev.h>
#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <loongson1.h>
#define OSC 33
static DEFINE_SPINLOCK(_lock);
static int ls1x_pll_clk_enable(struct clk_hw *hw)
{
return 0;
}
static void ls1x_pll_clk_disable(struct clk_hw *hw)
{
}
static unsigned long ls1x_pll_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
u32 pll, rate;
pll = __raw_readl(LS1X_CLK_PLL_FREQ);
rate = ((12 + (pll & 0x3f)) * 1000000) +
((((pll >> 8) & 0x3ff) * 1000000) >> 10);
rate *= OSC;
rate >>= 1;
return rate;
}
static const struct clk_ops ls1x_pll_clk_ops = {
.enable = ls1x_pll_clk_enable,
.disable = ls1x_pll_clk_disable,
.recalc_rate = ls1x_pll_recalc_rate,
};
static struct clk * __init clk_register_pll(struct device *dev,
const char *name, const char *parent_name, unsigned long flags)
{
struct clk_hw *hw;
struct clk *clk;
struct clk_init_data init;
/* allocate the divider */
hw = kzalloc(sizeof(struct clk_hw), GFP_KERNEL);
if (!hw) {
pr_err("%s: could not allocate clk_hw\n", __func__);
return ERR_PTR(-ENOMEM);
}
init.name = name;
init.ops = &ls1x_pll_clk_ops;
init.flags = flags | CLK_IS_BASIC;
init.parent_names = (parent_name ? &parent_name : NULL);
init.num_parents = (parent_name ? 1 : 0);
hw->init = &init;
/* register the clock */
clk = clk_register(dev, hw);
if (IS_ERR(clk))
kfree(hw);
return clk;
}
void __init ls1x_clk_init(void)
{
struct clk *clk;
clk = clk_register_pll(NULL, "pll_clk", NULL, CLK_IS_ROOT);
clk_prepare_enable(clk);
clk = clk_register_divider(NULL, "cpu_clk", "pll_clk",
CLK_SET_RATE_PARENT, LS1X_CLK_PLL_DIV, DIV_CPU_SHIFT,
DIV_CPU_WIDTH, CLK_DIVIDER_ONE_BASED, &_lock);
clk_prepare_enable(clk);
clk_register_clkdev(clk, "cpu", NULL);
clk = clk_register_divider(NULL, "dc_clk", "pll_clk",
CLK_SET_RATE_PARENT, LS1X_CLK_PLL_DIV, DIV_DC_SHIFT,
DIV_DC_WIDTH, CLK_DIVIDER_ONE_BASED, &_lock);
clk_prepare_enable(clk);
clk_register_clkdev(clk, "dc", NULL);
clk = clk_register_divider(NULL, "ahb_clk", "pll_clk",
CLK_SET_RATE_PARENT, LS1X_CLK_PLL_DIV, DIV_DDR_SHIFT,
DIV_DDR_WIDTH, CLK_DIVIDER_ONE_BASED, &_lock);
clk_prepare_enable(clk);
clk_register_clkdev(clk, "ahb", NULL);
clk_register_clkdev(clk, "stmmaceth", NULL);
clk = clk_register_fixed_factor(NULL, "apb_clk", "ahb_clk", 0, 1, 2);
clk_prepare_enable(clk);
clk_register_clkdev(clk, "apb", NULL);
clk_register_clkdev(clk, "serial8250", NULL);
}