arch/sh/kernel/cpu/hwblk.c

#include <linux/clk.h>
#include <linux/compiler.h>
#include <linux/io.h>
#include <linux/spinlock.h>
#include <asm/suspend.h>
#include <asm/hwblk.h>
#include <asm/clock.h>

static DEFINE_SPINLOCK(hwblk_lock);

static void hwblk_area_mod_cnt(struct hwblk_info *info,
			       int area, int counter, int value, int goal)
{
	struct hwblk_area *hap = info->areas + area;

	hap->cnt[counter] += value;

	if (hap->cnt[counter] != goal)
		return;

	if (hap->flags & HWBLK_AREA_FLAG_PARENT)
		hwblk_area_mod_cnt(info, hap->parent, counter, value, goal);
}


static int __hwblk_mod_cnt(struct hwblk_info *info, int hwblk,
			  int counter, int value, int goal)
{
	struct hwblk *hp = info->hwblks + hwblk;

	hp->cnt[counter] += value;
	if (hp->cnt[counter] == goal)
		hwblk_area_mod_cnt(info, hp->area, counter, value, goal);

	return hp->cnt[counter];
}

static void hwblk_mod_cnt(struct hwblk_info *info, int hwblk,
			  int counter, int value, int goal)
{
	unsigned long flags;

	spin_lock_irqsave(&hwblk_lock, flags);
	__hwblk_mod_cnt(info, hwblk, counter, value, goal);
	spin_unlock_irqrestore(&hwblk_lock, flags);
}

void hwblk_cnt_inc(struct hwblk_info *info, int hwblk, int counter)
{
	hwblk_mod_cnt(info, hwblk, counter, 1, 1);
}

void hwblk_cnt_dec(struct hwblk_info *info, int hwblk, int counter)
{
	hwblk_mod_cnt(info, hwblk, counter, -1, 0);
}

void hwblk_enable(struct hwblk_info *info, int hwblk)
{
	struct hwblk *hp = info->hwblks + hwblk;
	unsigned long tmp;
	unsigned long flags;
	int ret;

	spin_lock_irqsave(&hwblk_lock, flags);

	ret = __hwblk_mod_cnt(info, hwblk, HWBLK_CNT_USAGE, 1, 1);
	if (ret == 1) {
		tmp = __raw_readl(hp->mstp);
		tmp &= ~(1 << hp->bit);
		__raw_writel(tmp, hp->mstp);
	}

	spin_unlock_irqrestore(&hwblk_lock, flags);
}

void hwblk_disable(struct hwblk_info *info, int hwblk)
{
	struct hwblk *hp = info->hwblks + hwblk;
	unsigned long tmp;
	unsigned long flags;
	int ret;

	spin_lock_irqsave(&hwblk_lock, flags);

	ret = __hwblk_mod_cnt(info, hwblk, HWBLK_CNT_USAGE, -1, 0);
	if (ret == 0) {
		tmp = __raw_readl(hp->mstp);
		tmp |= 1 << hp->bit;
		__raw_writel(tmp, hp->mstp);
	}

	spin_unlock_irqrestore(&hwblk_lock, flags);
}

struct hwblk_info *hwblk_info;

int __init hwblk_register(struct hwblk_info *info)
{
	hwblk_info = info;
	return 0;
}

int __init __weak arch_hwblk_init(void)
{
	return 0;
}

int __weak arch_hwblk_sleep_mode(void)
{
	return SUSP_SH_SLEEP;
}

int __init hwblk_init(void)
{
	return arch_hwblk_init();
}

/* allow clocks to enable and disable hardware blocks */
static int sh_hwblk_clk_enable(struct clk *clk)
{
	if (!hwblk_info)
		return -ENOENT;

	hwblk_enable(hwblk_info, clk->arch_flags);
	return 0;
}

static void sh_hwblk_clk_disable(struct clk *clk)
{
	if (hwblk_info)
		hwblk_disable(hwblk_info, clk->arch_flags);
}

static struct clk_ops sh_hwblk_clk_ops = {
	.enable		= sh_hwblk_clk_enable,
	.disable	= sh_hwblk_clk_disable,
	.recalc		= followparent_recalc,
};

int __init sh_hwblk_clk_register(struct clk *clks, int nr)
{
	struct clk *clkp;
	int ret = 0;
	int k;

	for (k = 0; !ret && (k < nr); k++) {
		clkp = clks + k;

		/* skip over clocks using hwblk 0 (HWBLK_UNKNOWN) */
		if (!clkp->arch_flags)
			continue;

		clkp->ops = &sh_hwblk_clk_ops;
		ret |= clk_register(clkp);
	}

	return ret;
}