openwrt/target/linux/ramips/files/arch/mips/ralink/rt305x/clock.c

113 lines
2.3 KiB
C

/*
* Ralink RT305X clock API
*
* Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <asm/mach-ralink/common.h>
#include <asm/mach-ralink/rt305x.h>
#include <asm/mach-ralink/rt305x_regs.h>
#include "common.h"
struct clk {
unsigned long rate;
};
static struct clk rt305x_cpu_clk;
static struct clk rt305x_sys_clk;
static struct clk rt305x_wdt_clk;
static struct clk rt305x_uart_clk;
void __init rt305x_clocks_init(void)
{
u32 t;
t = rt305x_sysc_rr(SYSC_REG_SYSTEM_CONFIG);
if (soc_is_rt305x() || soc_is_rt3350()) {
t = (t >> RT305X_SYSCFG_CPUCLK_SHIFT) &
RT305X_SYSCFG_CPUCLK_MASK;
switch (t) {
case RT305X_SYSCFG_CPUCLK_LOW:
rt305x_cpu_clk.rate = 320000000;
break;
case RT305X_SYSCFG_CPUCLK_HIGH:
rt305x_cpu_clk.rate = 384000000;
break;
}
rt305x_sys_clk.rate = rt305x_cpu_clk.rate / 3;
rt305x_uart_clk.rate = rt305x_sys_clk.rate;
rt305x_wdt_clk.rate = rt305x_sys_clk.rate;
} else if (soc_is_rt3352()) {
t = (t >> RT3352_SYSCFG0_CPUCLK_SHIFT) &
RT3352_SYSCFG0_CPUCLK_MASK;
switch (t) {
case RT3352_SYSCFG0_CPUCLK_LOW:
rt305x_cpu_clk.rate = 384000000;
break;
case RT3352_SYSCFG0_CPUCLK_HIGH:
rt305x_cpu_clk.rate = 400000000;
break;
}
rt305x_sys_clk.rate = rt305x_cpu_clk.rate / 3;
rt305x_uart_clk.rate = rt305x_sys_clk.rate / 10;
rt305x_wdt_clk.rate = rt305x_sys_clk.rate;
} else {
BUG();
}
}
/*
* Linux clock API
*/
struct clk *clk_get(struct device *dev, const char *id)
{
if (!strcmp(id, "sys"))
return &rt305x_sys_clk;
if (!strcmp(id, "cpu"))
return &rt305x_cpu_clk;
if (!strcmp(id, "wdt"))
return &rt305x_wdt_clk;
if (!strcmp(id, "uart"))
return &rt305x_uart_clk;
return ERR_PTR(-ENOENT);
}
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);