blob: f87778ddeb60125cbd6e7ec610749ce00647a1a0 [file] [log] [blame]
/*
* (C) Copyright 2010 Quantenna Communications Inc.
*
* 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.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <linux/module.h>
#include <linux/io.h>
#include <linux/device.h>
#include <linux/err.h>
#include <asm/hardware.h>
#include <asm/board/platform.h>
struct clk {
unsigned long rate; /* Clock rate in HZ */
};
struct qtn_clk_lookup_entry {
const char *name;
struct clk *clk_p;
};
static struct clk qtn_clk_bus = {
.rate = 0,
};
static struct qtn_clk_lookup_entry qtn_clk_list[] = {
{ .name = "qtn-i2c.0", .clk_p = &qtn_clk_bus },
{ .name = "bus-clk", .clk_p = &qtn_clk_bus },
};
static unsigned long qtn_clk_get_bus_freq(void)
{
unsigned long freq = 0;
#ifdef CONFIG_ARC700_FPGA
freq = CONFIG_ARC700_FPGA_CLK;
#else
switch(readl(IO_ADDRESS(RUBY_SYS_CTL_CTRL)) & RUBY_SYS_CTL_MASK_CLKSEL) {
case RUBY_SYS_CTL_CLKSEL(0x0):
freq = RUBY_SYS_CTL_CLKSEL_00_BUS_FREQ;
break;
case RUBY_SYS_CTL_CLKSEL(0x1):
freq = RUBY_SYS_CTL_CLKSEL_01_BUS_FREQ;
break;
case RUBY_SYS_CTL_CLKSEL(0x2):
freq = RUBY_SYS_CTL_CLKSEL_10_BUS_FREQ;
break;
case RUBY_SYS_CTL_CLKSEL(0x3):
freq = RUBY_SYS_CTL_CLKSEL_11_BUS_FREQ;
break;
default:
panic("Logic error!\n");
break;
}
#endif
return freq;
}
static int __init qtn_clk_init_rates(void)
{
/* Clock source bits are latched on power-on */
qtn_clk_bus.rate = qtn_clk_get_bus_freq();
return 0;
}
arch_initcall(qtn_clk_init_rates);
struct clk *clk_get(struct device *dev, const char *id)
{
struct clk *ret_clk = NULL;
const char *dev_id = NULL;
int i;
if (dev) {
dev_id = dev_name(dev);
for (i = 0; i < ARRAY_SIZE(qtn_clk_list); ++i) {
if (!strcmp(dev_id, qtn_clk_list[i].name)) {
ret_clk = qtn_clk_list[i].clk_p;
break;
}
}
}
return ret_clk ? ret_clk : ERR_PTR(-ENOENT);
}
EXPORT_SYMBOL(clk_get);
unsigned long clk_get_rate(struct clk *clk)
{
return clk ? clk->rate : 0;
}
EXPORT_SYMBOL(clk_get_rate);