linux/linux-5.18.11/drivers/clk/mmp/pwr-island.c

116 lines
2.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* MMP PMU power island support
*
* Copyright (C) 2020 Lubomir Rintel <lkundrak@v3.sk>
*/
#include <linux/pm_domain.h>
#include <linux/slab.h>
#include <linux/io.h>
#include "clk.h"
#define to_mmp_pm_domain(genpd) container_of(genpd, struct mmp_pm_domain, genpd)
struct mmp_pm_domain {
struct generic_pm_domain genpd;
void __iomem *reg;
spinlock_t *lock;
u32 power_on;
u32 reset;
u32 clock_enable;
unsigned int flags;
};
static int mmp_pm_domain_power_on(struct generic_pm_domain *genpd)
{
struct mmp_pm_domain *pm_domain = to_mmp_pm_domain(genpd);
unsigned long flags = 0;
u32 val;
if (pm_domain->lock)
spin_lock_irqsave(pm_domain->lock, flags);
val = readl(pm_domain->reg);
/* Turn on the power island */
val |= pm_domain->power_on;
writel(val, pm_domain->reg);
/* Disable isolation */
val |= 0x100;
writel(val, pm_domain->reg);
/* Some blocks need to be reset after a power up */
if (pm_domain->reset || pm_domain->clock_enable) {
u32 after_power_on = val;
val &= ~pm_domain->reset;
writel(val, pm_domain->reg);
val |= pm_domain->clock_enable;
writel(val, pm_domain->reg);
val |= pm_domain->reset;
writel(val, pm_domain->reg);
writel(after_power_on, pm_domain->reg);
}
if (pm_domain->lock)
spin_unlock_irqrestore(pm_domain->lock, flags);
return 0;
}
static int mmp_pm_domain_power_off(struct generic_pm_domain *genpd)
{
struct mmp_pm_domain *pm_domain = to_mmp_pm_domain(genpd);
unsigned long flags = 0;
u32 val;
if (pm_domain->flags & MMP_PM_DOMAIN_NO_DISABLE)
return 0;
if (pm_domain->lock)
spin_lock_irqsave(pm_domain->lock, flags);
/* Turn off and isolate the power island. */
val = readl(pm_domain->reg);
val &= ~pm_domain->power_on;
val &= ~0x100;
writel(val, pm_domain->reg);
if (pm_domain->lock)
spin_unlock_irqrestore(pm_domain->lock, flags);
return 0;
}
struct generic_pm_domain *mmp_pm_domain_register(const char *name,
void __iomem *reg,
u32 power_on, u32 reset, u32 clock_enable,
unsigned int flags, spinlock_t *lock)
{
struct mmp_pm_domain *pm_domain;
pm_domain = kzalloc(sizeof(*pm_domain), GFP_KERNEL);
if (!pm_domain)
return ERR_PTR(-ENOMEM);
pm_domain->reg = reg;
pm_domain->power_on = power_on;
pm_domain->reset = reset;
pm_domain->clock_enable = clock_enable;
pm_domain->flags = flags;
pm_domain->lock = lock;
pm_genpd_init(&pm_domain->genpd, NULL, true);
pm_domain->genpd.name = name;
pm_domain->genpd.power_on = mmp_pm_domain_power_on;
pm_domain->genpd.power_off = mmp_pm_domain_power_off;
return &pm_domain->genpd;
}