diff options
Diffstat (limited to 'drivers/clk/mmp/pwr-island.c')
-rw-r--r-- | drivers/clk/mmp/pwr-island.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/drivers/clk/mmp/pwr-island.c b/drivers/clk/mmp/pwr-island.c new file mode 100644 index 000000000..edaa2433a --- /dev/null +++ b/drivers/clk/mmp/pwr-island.c @@ -0,0 +1,115 @@ +// 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; +} |