linux-stable-rt/arch/sh/kernel/cpu/sh4a/clock-sh7757.c

140 lines
3.3 KiB
C

/*
* arch/sh/kernel/cpu/sh4/clock-sh7757.c
*
* SH7757 support for the clock framework
*
* Copyright (C) 2009 Renesas Solutions Corp.
*
* 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 <linux/io.h>
#include <asm/clkdev.h>
#include <asm/clock.h>
#include <asm/freq.h>
static int ifc_divisors[] = { 2, 1, 4, 1, 1, 8, 1, 1,
16, 1, 1, 32, 1, 1, 1, 1 };
static int sfc_divisors[] = { 2, 1, 4, 1, 1, 8, 1, 1,
16, 1, 1, 32, 1, 1, 1, 1 };
static int bfc_divisors[] = { 2, 1, 4, 1, 1, 8, 1, 1,
16, 1, 1, 32, 1, 1, 1, 1 };
static int p1fc_divisors[] = { 2, 1, 4, 1, 1, 8, 1, 1,
16, 1, 1, 32, 1, 1, 1, 1 };
static void master_clk_init(struct clk *clk)
{
clk->rate = CONFIG_SH_PCLK_FREQ * 16;
}
static struct clk_ops sh7757_master_clk_ops = {
.init = master_clk_init,
};
static void module_clk_recalc(struct clk *clk)
{
int idx = __raw_readl(FRQCR) & 0x0000000f;
clk->rate = clk->parent->rate / p1fc_divisors[idx];
}
static struct clk_ops sh7757_module_clk_ops = {
.recalc = module_clk_recalc,
};
static void bus_clk_recalc(struct clk *clk)
{
int idx = (__raw_readl(FRQCR) >> 8) & 0x0000000f;
clk->rate = clk->parent->rate / bfc_divisors[idx];
}
static struct clk_ops sh7757_bus_clk_ops = {
.recalc = bus_clk_recalc,
};
static void cpu_clk_recalc(struct clk *clk)
{
int idx = (__raw_readl(FRQCR) >> 20) & 0x0000000f;
clk->rate = clk->parent->rate / ifc_divisors[idx];
}
static struct clk_ops sh7757_cpu_clk_ops = {
.recalc = cpu_clk_recalc,
};
static struct clk_ops *sh7757_clk_ops[] = {
&sh7757_master_clk_ops,
&sh7757_module_clk_ops,
&sh7757_bus_clk_ops,
&sh7757_cpu_clk_ops,
};
void __init arch_init_clk_ops(struct clk_ops **ops, int idx)
{
if (idx < ARRAY_SIZE(sh7757_clk_ops))
*ops = sh7757_clk_ops[idx];
}
static void shyway_clk_recalc(struct clk *clk)
{
int idx = (__raw_readl(FRQCR) >> 12) & 0x0000000f;
clk->rate = clk->parent->rate / sfc_divisors[idx];
}
static struct clk_ops sh7757_shyway_clk_ops = {
.recalc = shyway_clk_recalc,
};
static struct clk sh7757_shyway_clk = {
.flags = CLK_ENABLE_ON_INIT,
.ops = &sh7757_shyway_clk_ops,
};
/*
* Additional sh7757-specific on-chip clocks that aren't already part of the
* clock framework
*/
static struct clk *sh7757_onchip_clocks[] = {
&sh7757_shyway_clk,
};
#define CLKDEV_CON_ID(_id, _clk) { .con_id = _id, .clk = _clk }
static struct clk_lookup lookups[] = {
/* main clocks */
CLKDEV_CON_ID("shyway_clk", &sh7757_shyway_clk),
};
static int __init sh7757_clk_init(void)
{
struct clk *clk = clk_get(NULL, "master_clk");
int i;
for (i = 0; i < ARRAY_SIZE(sh7757_onchip_clocks); i++) {
struct clk *clkp = sh7757_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);
clkdev_add_table(lookups, ARRAY_SIZE(lookups));
return 0;
}
arch_initcall(sh7757_clk_init);