original_kernel/arch/sh/kernel/cpu/sh3/clock-sh7705.c

85 lines
2.1 KiB
C
Raw Normal View History

/*
* arch/sh/kernel/cpu/sh3/clock-sh7705.c
*
* SH7705 support for the clock framework
*
* Copyright (C) 2005 Paul Mundt
*
* FRQCR parsing hacked out of arch/sh/kernel/time.c
*
* Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
* Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
* Copyright (C) 2002, 2003, 2004 Paul Mundt
* Copyright (C) 2002 M. R. Brown <mrbrown@linux-sh.org>
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <asm/clock.h>
#include <asm/freq.h>
#include <asm/io.h>
/*
* SH7705 uses the same divisors as the generic SH-3 case, it's just the
* FRQCR layout that is a bit different..
*/
static int stc_multipliers[] = { 1, 2, 3, 4, 6, 1, 1, 1 };
static int ifc_divisors[] = { 1, 2, 3, 4, 1, 1, 1, 1 };
static int pfc_divisors[] = { 1, 2, 3, 4, 6, 1, 1, 1 };
static void master_clk_init(struct clk *clk)
{
clk->rate *= pfc_divisors[ctrl_inw(FRQCR) & 0x0003];
}
static struct clk_ops sh7705_master_clk_ops = {
.init = master_clk_init,
};
static void module_clk_recalc(struct clk *clk)
{
int idx = ctrl_inw(FRQCR) & 0x0003;
clk->rate = clk->parent->rate / pfc_divisors[idx];
}
static struct clk_ops sh7705_module_clk_ops = {
.recalc = module_clk_recalc,
};
static void bus_clk_recalc(struct clk *clk)
{
int idx = (ctrl_inw(FRQCR) & 0x0300) >> 8;
clk->rate = clk->parent->rate / stc_multipliers[idx];
}
static struct clk_ops sh7705_bus_clk_ops = {
.recalc = bus_clk_recalc,
};
static void cpu_clk_recalc(struct clk *clk)
{
int idx = (ctrl_inw(FRQCR) & 0x0030) >> 4;
clk->rate = clk->parent->rate / ifc_divisors[idx];
}
static struct clk_ops sh7705_cpu_clk_ops = {
.recalc = cpu_clk_recalc,
};
static struct clk_ops *sh7705_clk_ops[] = {
&sh7705_master_clk_ops,
&sh7705_module_clk_ops,
&sh7705_bus_clk_ops,
&sh7705_cpu_clk_ops,
};
void __init arch_init_clk_ops(struct clk_ops **ops, int idx)
{
if (idx < ARRAY_SIZE(sh7705_clk_ops))
*ops = sh7705_clk_ops[idx];
}