diff options
Diffstat (limited to 'drivers/clk/stm32/clk-stm32-core.c')
-rw-r--r-- | drivers/clk/stm32/clk-stm32-core.c | 695 |
1 files changed, 695 insertions, 0 deletions
diff --git a/drivers/clk/stm32/clk-stm32-core.c b/drivers/clk/stm32/clk-stm32-core.c new file mode 100644 index 000000000..45a279e73 --- /dev/null +++ b/drivers/clk/stm32/clk-stm32-core.c @@ -0,0 +1,695 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) STMicroelectronics 2022 - All Rights Reserved + * Author: Gabriel Fernandez <gabriel.fernandez@foss.st.com> for STMicroelectronics. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/slab.h> +#include <linux/spinlock.h> + +#include "clk-stm32-core.h" +#include "reset-stm32.h" + +static DEFINE_SPINLOCK(rlock); + +static int stm32_rcc_clock_init(struct device *dev, + const struct of_device_id *match, + void __iomem *base) +{ + const struct stm32_rcc_match_data *data = match->data; + struct clk_hw_onecell_data *clk_data = data->hw_clks; + struct device_node *np = dev_of_node(dev); + struct clk_hw **hws; + int n, max_binding; + + max_binding = data->maxbinding; + + clk_data = devm_kzalloc(dev, struct_size(clk_data, hws, max_binding), GFP_KERNEL); + if (!clk_data) + return -ENOMEM; + + clk_data->num = max_binding; + + hws = clk_data->hws; + + for (n = 0; n < max_binding; n++) + hws[n] = ERR_PTR(-ENOENT); + + for (n = 0; n < data->num_clocks; n++) { + const struct clock_config *cfg_clock = &data->tab_clocks[n]; + struct clk_hw *hw = ERR_PTR(-ENOENT); + + if (data->check_security && + data->check_security(base, cfg_clock)) + continue; + + if (cfg_clock->func) + hw = (*cfg_clock->func)(dev, data, base, &rlock, + cfg_clock); + + if (IS_ERR(hw)) { + dev_err(dev, "Can't register clk %d: %ld\n", n, + PTR_ERR(hw)); + return PTR_ERR(hw); + } + + if (cfg_clock->id != NO_ID) + hws[cfg_clock->id] = hw; + } + + return of_clk_add_hw_provider(np, of_clk_hw_onecell_get, clk_data); +} + +int stm32_rcc_init(struct device *dev, const struct of_device_id *match_data, + void __iomem *base) +{ + const struct of_device_id *match; + int err; + + match = of_match_node(match_data, dev_of_node(dev)); + if (!match) { + dev_err(dev, "match data not found\n"); + return -ENODEV; + } + + /* RCC Reset Configuration */ + err = stm32_rcc_reset_init(dev, match, base); + if (err) { + pr_err("stm32 reset failed to initialize\n"); + return err; + } + + /* RCC Clock Configuration */ + err = stm32_rcc_clock_init(dev, match, base); + if (err) { + pr_err("stm32 clock failed to initialize\n"); + return err; + } + + return 0; +} + +static u8 stm32_mux_get_parent(void __iomem *base, + struct clk_stm32_clock_data *data, + u16 mux_id) +{ + const struct stm32_mux_cfg *mux = &data->muxes[mux_id]; + u32 mask = BIT(mux->width) - 1; + u32 val; + + val = readl(base + mux->offset) >> mux->shift; + val &= mask; + + return val; +} + +static int stm32_mux_set_parent(void __iomem *base, + struct clk_stm32_clock_data *data, + u16 mux_id, u8 index) +{ + const struct stm32_mux_cfg *mux = &data->muxes[mux_id]; + + u32 mask = BIT(mux->width) - 1; + u32 reg = readl(base + mux->offset); + u32 val = index << mux->shift; + + reg &= ~(mask << mux->shift); + reg |= val; + + writel(reg, base + mux->offset); + + return 0; +} + +static void stm32_gate_endisable(void __iomem *base, + struct clk_stm32_clock_data *data, + u16 gate_id, int enable) +{ + const struct stm32_gate_cfg *gate = &data->gates[gate_id]; + void __iomem *addr = base + gate->offset; + + if (enable) { + if (data->gate_cpt[gate_id]++ > 0) + return; + + if (gate->set_clr != 0) + writel(BIT(gate->bit_idx), addr); + else + writel(readl(addr) | BIT(gate->bit_idx), addr); + } else { + if (--data->gate_cpt[gate_id] > 0) + return; + + if (gate->set_clr != 0) + writel(BIT(gate->bit_idx), addr + gate->set_clr); + else + writel(readl(addr) & ~BIT(gate->bit_idx), addr); + } +} + +static void stm32_gate_disable_unused(void __iomem *base, + struct clk_stm32_clock_data *data, + u16 gate_id) +{ + const struct stm32_gate_cfg *gate = &data->gates[gate_id]; + void __iomem *addr = base + gate->offset; + + if (data->gate_cpt[gate_id] > 0) + return; + + if (gate->set_clr != 0) + writel(BIT(gate->bit_idx), addr + gate->set_clr); + else + writel(readl(addr) & ~BIT(gate->bit_idx), addr); +} + +static int stm32_gate_is_enabled(void __iomem *base, + struct clk_stm32_clock_data *data, + u16 gate_id) +{ + const struct stm32_gate_cfg *gate = &data->gates[gate_id]; + + return (readl(base + gate->offset) & BIT(gate->bit_idx)) != 0; +} + +static unsigned int _get_table_div(const struct clk_div_table *table, + unsigned int val) +{ + const struct clk_div_table *clkt; + + for (clkt = table; clkt->div; clkt++) + if (clkt->val == val) + return clkt->div; + return 0; +} + +static unsigned int _get_div(const struct clk_div_table *table, + unsigned int val, unsigned long flags, u8 width) +{ + if (flags & CLK_DIVIDER_ONE_BASED) + return val; + if (flags & CLK_DIVIDER_POWER_OF_TWO) + return 1 << val; + if (table) + return _get_table_div(table, val); + return val + 1; +} + +static unsigned long stm32_divider_get_rate(void __iomem *base, + struct clk_stm32_clock_data *data, + u16 div_id, + unsigned long parent_rate) +{ + const struct stm32_div_cfg *divider = &data->dividers[div_id]; + unsigned int val; + unsigned int div; + + val = readl(base + divider->offset) >> divider->shift; + val &= clk_div_mask(divider->width); + div = _get_div(divider->table, val, divider->flags, divider->width); + + if (!div) { + WARN(!(divider->flags & CLK_DIVIDER_ALLOW_ZERO), + "%d: Zero divisor and CLK_DIVIDER_ALLOW_ZERO not set\n", + div_id); + return parent_rate; + } + + return DIV_ROUND_UP_ULL((u64)parent_rate, div); +} + +static int stm32_divider_set_rate(void __iomem *base, + struct clk_stm32_clock_data *data, + u16 div_id, unsigned long rate, + unsigned long parent_rate) +{ + const struct stm32_div_cfg *divider = &data->dividers[div_id]; + int value; + u32 val; + + value = divider_get_val(rate, parent_rate, divider->table, + divider->width, divider->flags); + if (value < 0) + return value; + + if (divider->flags & CLK_DIVIDER_HIWORD_MASK) { + val = clk_div_mask(divider->width) << (divider->shift + 16); + } else { + val = readl(base + divider->offset); + val &= ~(clk_div_mask(divider->width) << divider->shift); + } + + val |= (u32)value << divider->shift; + + writel(val, base + divider->offset); + + return 0; +} + +static u8 clk_stm32_mux_get_parent(struct clk_hw *hw) +{ + struct clk_stm32_mux *mux = to_clk_stm32_mux(hw); + + return stm32_mux_get_parent(mux->base, mux->clock_data, mux->mux_id); +} + +static int clk_stm32_mux_set_parent(struct clk_hw *hw, u8 index) +{ + struct clk_stm32_mux *mux = to_clk_stm32_mux(hw); + unsigned long flags = 0; + + spin_lock_irqsave(mux->lock, flags); + + stm32_mux_set_parent(mux->base, mux->clock_data, mux->mux_id, index); + + spin_unlock_irqrestore(mux->lock, flags); + + return 0; +} + +const struct clk_ops clk_stm32_mux_ops = { + .get_parent = clk_stm32_mux_get_parent, + .set_parent = clk_stm32_mux_set_parent, +}; + +static void clk_stm32_gate_endisable(struct clk_hw *hw, int enable) +{ + struct clk_stm32_gate *gate = to_clk_stm32_gate(hw); + unsigned long flags = 0; + + spin_lock_irqsave(gate->lock, flags); + + stm32_gate_endisable(gate->base, gate->clock_data, gate->gate_id, enable); + + spin_unlock_irqrestore(gate->lock, flags); +} + +static int clk_stm32_gate_enable(struct clk_hw *hw) +{ + clk_stm32_gate_endisable(hw, 1); + + return 0; +} + +static void clk_stm32_gate_disable(struct clk_hw *hw) +{ + clk_stm32_gate_endisable(hw, 0); +} + +static int clk_stm32_gate_is_enabled(struct clk_hw *hw) +{ + struct clk_stm32_gate *gate = to_clk_stm32_gate(hw); + + return stm32_gate_is_enabled(gate->base, gate->clock_data, gate->gate_id); +} + +static void clk_stm32_gate_disable_unused(struct clk_hw *hw) +{ + struct clk_stm32_gate *gate = to_clk_stm32_gate(hw); + unsigned long flags = 0; + + spin_lock_irqsave(gate->lock, flags); + + stm32_gate_disable_unused(gate->base, gate->clock_data, gate->gate_id); + + spin_unlock_irqrestore(gate->lock, flags); +} + +const struct clk_ops clk_stm32_gate_ops = { + .enable = clk_stm32_gate_enable, + .disable = clk_stm32_gate_disable, + .is_enabled = clk_stm32_gate_is_enabled, + .disable_unused = clk_stm32_gate_disable_unused, +}; + +static int clk_stm32_divider_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_stm32_div *div = to_clk_stm32_divider(hw); + unsigned long flags = 0; + int ret; + + if (div->div_id == NO_STM32_DIV) + return rate; + + spin_lock_irqsave(div->lock, flags); + + ret = stm32_divider_set_rate(div->base, div->clock_data, div->div_id, rate, parent_rate); + + spin_unlock_irqrestore(div->lock, flags); + + return ret; +} + +static long clk_stm32_divider_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + struct clk_stm32_div *div = to_clk_stm32_divider(hw); + const struct stm32_div_cfg *divider; + + if (div->div_id == NO_STM32_DIV) + return rate; + + divider = &div->clock_data->dividers[div->div_id]; + + /* if read only, just return current value */ + if (divider->flags & CLK_DIVIDER_READ_ONLY) { + u32 val; + + val = readl(div->base + divider->offset) >> divider->shift; + val &= clk_div_mask(divider->width); + + return divider_ro_round_rate(hw, rate, prate, divider->table, + divider->width, divider->flags, + val); + } + + return divider_round_rate_parent(hw, clk_hw_get_parent(hw), + rate, prate, divider->table, + divider->width, divider->flags); +} + +static unsigned long clk_stm32_divider_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_stm32_div *div = to_clk_stm32_divider(hw); + + if (div->div_id == NO_STM32_DIV) + return parent_rate; + + return stm32_divider_get_rate(div->base, div->clock_data, div->div_id, parent_rate); +} + +const struct clk_ops clk_stm32_divider_ops = { + .recalc_rate = clk_stm32_divider_recalc_rate, + .round_rate = clk_stm32_divider_round_rate, + .set_rate = clk_stm32_divider_set_rate, +}; + +static int clk_stm32_composite_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + unsigned long flags = 0; + int ret; + + if (composite->div_id == NO_STM32_DIV) + return rate; + + spin_lock_irqsave(composite->lock, flags); + + ret = stm32_divider_set_rate(composite->base, composite->clock_data, + composite->div_id, rate, parent_rate); + + spin_unlock_irqrestore(composite->lock, flags); + + return ret; +} + +static unsigned long clk_stm32_composite_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + + if (composite->div_id == NO_STM32_DIV) + return parent_rate; + + return stm32_divider_get_rate(composite->base, composite->clock_data, + composite->div_id, parent_rate); +} + +static long clk_stm32_composite_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + + const struct stm32_div_cfg *divider; + + if (composite->div_id == NO_STM32_DIV) + return rate; + + divider = &composite->clock_data->dividers[composite->div_id]; + + /* if read only, just return current value */ + if (divider->flags & CLK_DIVIDER_READ_ONLY) { + u32 val; + + val = readl(composite->base + divider->offset) >> divider->shift; + val &= clk_div_mask(divider->width); + + return divider_ro_round_rate(hw, rate, prate, divider->table, + divider->width, divider->flags, + val); + } + + return divider_round_rate_parent(hw, clk_hw_get_parent(hw), + rate, prate, divider->table, + divider->width, divider->flags); +} + +static u8 clk_stm32_composite_get_parent(struct clk_hw *hw) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + + return stm32_mux_get_parent(composite->base, composite->clock_data, composite->mux_id); +} + +static int clk_stm32_composite_set_parent(struct clk_hw *hw, u8 index) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + unsigned long flags = 0; + + spin_lock_irqsave(composite->lock, flags); + + stm32_mux_set_parent(composite->base, composite->clock_data, composite->mux_id, index); + + spin_unlock_irqrestore(composite->lock, flags); + + if (composite->clock_data->is_multi_mux) { + struct clk_hw *other_mux_hw = composite->clock_data->is_multi_mux(hw); + + if (other_mux_hw) { + struct clk_hw *hwp = clk_hw_get_parent_by_index(hw, index); + + clk_hw_reparent(other_mux_hw, hwp); + } + } + + return 0; +} + +static int clk_stm32_composite_is_enabled(struct clk_hw *hw) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + + if (composite->gate_id == NO_STM32_GATE) + return (__clk_get_enable_count(hw->clk) > 0); + + return stm32_gate_is_enabled(composite->base, composite->clock_data, composite->gate_id); +} + +#define MUX_SAFE_POSITION 0 + +static int clk_stm32_has_safe_mux(struct clk_hw *hw) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + const struct stm32_mux_cfg *mux = &composite->clock_data->muxes[composite->mux_id]; + + return !!(mux->flags & MUX_SAFE); +} + +static void clk_stm32_set_safe_position_mux(struct clk_hw *hw) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + + if (!clk_stm32_composite_is_enabled(hw)) { + unsigned long flags = 0; + + if (composite->clock_data->is_multi_mux) { + struct clk_hw *other_mux_hw = NULL; + + other_mux_hw = composite->clock_data->is_multi_mux(hw); + + if (!other_mux_hw || clk_stm32_composite_is_enabled(other_mux_hw)) + return; + } + + spin_lock_irqsave(composite->lock, flags); + + stm32_mux_set_parent(composite->base, composite->clock_data, + composite->mux_id, MUX_SAFE_POSITION); + + spin_unlock_irqrestore(composite->lock, flags); + } +} + +static void clk_stm32_safe_restore_position_mux(struct clk_hw *hw) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + int sel = clk_hw_get_parent_index(hw); + unsigned long flags = 0; + + spin_lock_irqsave(composite->lock, flags); + + stm32_mux_set_parent(composite->base, composite->clock_data, composite->mux_id, sel); + + spin_unlock_irqrestore(composite->lock, flags); +} + +static void clk_stm32_composite_gate_endisable(struct clk_hw *hw, int enable) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + unsigned long flags = 0; + + spin_lock_irqsave(composite->lock, flags); + + stm32_gate_endisable(composite->base, composite->clock_data, composite->gate_id, enable); + + spin_unlock_irqrestore(composite->lock, flags); +} + +static int clk_stm32_composite_gate_enable(struct clk_hw *hw) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + + if (composite->gate_id == NO_STM32_GATE) + return 0; + + clk_stm32_composite_gate_endisable(hw, 1); + + if (composite->mux_id != NO_STM32_MUX && clk_stm32_has_safe_mux(hw)) + clk_stm32_safe_restore_position_mux(hw); + + return 0; +} + +static void clk_stm32_composite_gate_disable(struct clk_hw *hw) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + + if (composite->gate_id == NO_STM32_GATE) + return; + + clk_stm32_composite_gate_endisable(hw, 0); + + if (composite->mux_id != NO_STM32_MUX && clk_stm32_has_safe_mux(hw)) + clk_stm32_set_safe_position_mux(hw); +} + +static void clk_stm32_composite_disable_unused(struct clk_hw *hw) +{ + struct clk_stm32_composite *composite = to_clk_stm32_composite(hw); + unsigned long flags = 0; + + if (composite->gate_id == NO_STM32_GATE) + return; + + spin_lock_irqsave(composite->lock, flags); + + stm32_gate_disable_unused(composite->base, composite->clock_data, composite->gate_id); + + spin_unlock_irqrestore(composite->lock, flags); +} + +const struct clk_ops clk_stm32_composite_ops = { + .set_rate = clk_stm32_composite_set_rate, + .recalc_rate = clk_stm32_composite_recalc_rate, + .round_rate = clk_stm32_composite_round_rate, + .get_parent = clk_stm32_composite_get_parent, + .set_parent = clk_stm32_composite_set_parent, + .enable = clk_stm32_composite_gate_enable, + .disable = clk_stm32_composite_gate_disable, + .is_enabled = clk_stm32_composite_is_enabled, + .disable_unused = clk_stm32_composite_disable_unused, +}; + +struct clk_hw *clk_stm32_mux_register(struct device *dev, + const struct stm32_rcc_match_data *data, + void __iomem *base, + spinlock_t *lock, + const struct clock_config *cfg) +{ + struct clk_stm32_mux *mux = cfg->clock_cfg; + struct clk_hw *hw = &mux->hw; + int err; + + mux->base = base; + mux->lock = lock; + mux->clock_data = data->clock_data; + + err = clk_hw_register(dev, hw); + if (err) + return ERR_PTR(err); + + return hw; +} + +struct clk_hw *clk_stm32_gate_register(struct device *dev, + const struct stm32_rcc_match_data *data, + void __iomem *base, + spinlock_t *lock, + const struct clock_config *cfg) +{ + struct clk_stm32_gate *gate = cfg->clock_cfg; + struct clk_hw *hw = &gate->hw; + int err; + + gate->base = base; + gate->lock = lock; + gate->clock_data = data->clock_data; + + err = clk_hw_register(dev, hw); + if (err) + return ERR_PTR(err); + + return hw; +} + +struct clk_hw *clk_stm32_div_register(struct device *dev, + const struct stm32_rcc_match_data *data, + void __iomem *base, + spinlock_t *lock, + const struct clock_config *cfg) +{ + struct clk_stm32_div *div = cfg->clock_cfg; + struct clk_hw *hw = &div->hw; + int err; + + div->base = base; + div->lock = lock; + div->clock_data = data->clock_data; + + err = clk_hw_register(dev, hw); + if (err) + return ERR_PTR(err); + + return hw; +} + +struct clk_hw *clk_stm32_composite_register(struct device *dev, + const struct stm32_rcc_match_data *data, + void __iomem *base, + spinlock_t *lock, + const struct clock_config *cfg) +{ + struct clk_stm32_composite *composite = cfg->clock_cfg; + struct clk_hw *hw = &composite->hw; + int err; + + composite->base = base; + composite->lock = lock; + composite->clock_data = data->clock_data; + + err = clk_hw_register(dev, hw); + if (err) + return ERR_PTR(err); + + return hw; +} |