linux-stable-rt/arch/sh/kernel/cpu/sh4a/clock-sh7780.c

127 lines
2.9 KiB
C

/*
* arch/sh/kernel/cpu/sh4/clock-sh7780.c
*
* SH7780 support for the clock framework
*
* Copyright (C) 2005 Paul Mundt
*
* 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>
static int ifc_divisors[] = { 2, 4 };
static int bfc_divisors[] = { 1, 1, 1, 8, 12, 16, 24, 1 };
static int pfc_divisors[] = { 1, 24, 24, 1 };
static int cfc_divisors[] = { 1, 1, 4, 1, 6, 1, 1, 1 };
static void master_clk_init(struct clk *clk)
{
clk->rate *= pfc_divisors[ctrl_inl(FRQCR) & 0x0003];
}
static struct clk_ops sh7780_master_clk_ops = {
.init = master_clk_init,
};
static void module_clk_recalc(struct clk *clk)
{
int idx = (ctrl_inl(FRQCR) & 0x0003);
clk->rate = clk->parent->rate / pfc_divisors[idx];
}
static struct clk_ops sh7780_module_clk_ops = {
.recalc = module_clk_recalc,
};
static void bus_clk_recalc(struct clk *clk)
{
int idx = ((ctrl_inl(FRQCR) >> 16) & 0x0007);
clk->rate = clk->parent->rate / bfc_divisors[idx];
}
static struct clk_ops sh7780_bus_clk_ops = {
.recalc = bus_clk_recalc,
};
static void cpu_clk_recalc(struct clk *clk)
{
int idx = ((ctrl_inl(FRQCR) >> 24) & 0x0001);
clk->rate = clk->parent->rate / ifc_divisors[idx];
}
static struct clk_ops sh7780_cpu_clk_ops = {
.recalc = cpu_clk_recalc,
};
static struct clk_ops *sh7780_clk_ops[] = {
&sh7780_master_clk_ops,
&sh7780_module_clk_ops,
&sh7780_bus_clk_ops,
&sh7780_cpu_clk_ops,
};
void __init arch_init_clk_ops(struct clk_ops **ops, int idx)
{
if (idx < ARRAY_SIZE(sh7780_clk_ops))
*ops = sh7780_clk_ops[idx];
}
static void shyway_clk_recalc(struct clk *clk)
{
int idx = ((ctrl_inl(FRQCR) >> 20) & 0x0007);
clk->rate = clk->parent->rate / cfc_divisors[idx];
}
static struct clk_ops sh7780_shyway_clk_ops = {
.recalc = shyway_clk_recalc,
};
static struct clk sh7780_shyway_clk = {
.name = "shyway_clk",
.flags = CLK_ALWAYS_ENABLED,
.ops = &sh7780_shyway_clk_ops,
};
/*
* Additional SH7780-specific on-chip clocks that aren't already part of the
* clock framework
*/
static struct clk *sh7780_onchip_clocks[] = {
&sh7780_shyway_clk,
};
static int __init sh7780_clk_init(void)
{
struct clk *clk = clk_get(NULL, "master_clk");
int i;
for (i = 0; i < ARRAY_SIZE(sh7780_onchip_clocks); i++) {
struct clk *clkp = sh7780_onchip_clocks[i];
clkp->parent = clk;
clk_register(clkp);
clk_enable(clkp);
}
/*
* Now that we have the rest of the clocks registered, we need to
* force the parent clock to propagate so that these clocks will
* automatically figure out their rate. We cheat by handing the
* parent clock its current rate and forcing child propagation.
*/
clk_set_rate(clk, clk_get_rate(clk));
clk_put(clk);
return 0;
}
arch_initcall(sh7780_clk_init);