diff options
Diffstat (limited to 'drivers/clk/eswin/clk.c')
| -rw-r--r-- | drivers/clk/eswin/clk.c | 586 |
1 files changed, 586 insertions, 0 deletions
diff --git a/drivers/clk/eswin/clk.c b/drivers/clk/eswin/clk.c new file mode 100644 index 000000000..e09a52cc3 --- /dev/null +++ b/drivers/clk/eswin/clk.c @@ -0,0 +1,586 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2026, Beijing ESWIN Computing Technology Co., Ltd.. + * All rights reserved. + * + * Authors: + * Yifeng Huang <huangyifeng@eswincomputing.com> + * Xuyang Dong <dongxuyang@eswincomputing.com> + */ + +#include <linux/bitfield.h> +#include <linux/clk-provider.h> +#include <linux/iopoll.h> +#include <linux/math.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#include "common.h" + +#define PLL_EN_MASK GENMASK(1, 0) +#define PLL_REFDIV_MASK GENMASK(17, 12) +#define PLL_FBDIV_MASK GENMASK(31, 20) +#define PLL_FRAC_MASK GENMASK(27, 4) +#define PLL_POSTDIV1_MASK GENMASK(10, 8) +#define PLL_POSTDIV2_MASK GENMASK(18, 16) + +struct eswin_clock_data *eswin_clk_init(struct platform_device *pdev, + size_t nr_clks) +{ + struct eswin_clock_data *eclk_data; + + eclk_data = devm_kzalloc(&pdev->dev, + struct_size(eclk_data, clk_data.hws, nr_clks), + GFP_KERNEL); + if (!eclk_data) + return ERR_PTR(-ENOMEM); + + eclk_data->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(eclk_data->base)) + return ERR_PTR(-EINVAL); + + eclk_data->clk_data.num = nr_clks; + spin_lock_init(&eclk_data->lock); + + return eclk_data; +} +EXPORT_SYMBOL_GPL(eswin_clk_init); + +/** + * eswin_calc_pll - calculate PLL values + * @frac_val: fractional divider + * @fbdiv_val: feedback divider + * @rate: reference rate + * @parent_rate: parent rate + * + * Calculate PLL values for frac and fbdiv: + * fbdiv = rate * 4 / parent_rate + * frac = (rate * 4 % parent_rate * (2 ^ 24)) / parent_rate + */ +static void eswin_calc_pll(u32 *frac_val, u32 *fbdiv_val, unsigned long rate, + unsigned long parent_rate) +{ + u32 rem; + u64 tmp; + + /* step 1: rate * 4 */ + tmp = rate * 4; + /* step 2: use do_div() to get the quotient(tmp) and remainder(rem) */ + rem = do_div(tmp, (u32)parent_rate); + /* fbdiv = rate * 4 / parent_rate */ + *fbdiv_val = (u32)tmp; + /* + * step 3: rem << 24 + * 24: 24-bit fractional accuracy + */ + tmp = (u64)rem << 24; + /* step 4: use do_div() to get the quotient(tmp) */ + do_div(tmp, (u32)parent_rate); + /* frac = (rate * 4 % parent_rate * (2 ^ 24)) / parent_rate */ + *frac_val = (u32)tmp; +} + +static inline struct eswin_clk_pll *to_pll_clk(struct clk_hw *hw) +{ + return container_of(hw, struct eswin_clk_pll, hw); +} + +static int clk_pll_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct eswin_clk_pll *clk = to_pll_clk(hw); + u32 frac_val, fbdiv_val, val, mask; + int ret; + + eswin_calc_pll(&frac_val, &fbdiv_val, rate, parent_rate); + + /* First, disable pll */ + val = readl_relaxed(clk->ctrl_reg0); + val &= ~PLL_EN_MASK; + val |= FIELD_PREP(PLL_EN_MASK, 0); + writel_relaxed(val, clk->ctrl_reg0); + + val = readl_relaxed(clk->ctrl_reg0); + val &= ~(PLL_REFDIV_MASK | PLL_FBDIV_MASK); + val |= FIELD_PREP(PLL_FBDIV_MASK, fbdiv_val); + val |= FIELD_PREP(PLL_REFDIV_MASK, 1); + writel_relaxed(val, clk->ctrl_reg0); + + val = readl_relaxed(clk->ctrl_reg1); + val &= ~PLL_FRAC_MASK; + val |= FIELD_PREP(PLL_FRAC_MASK, frac_val); + writel_relaxed(val, clk->ctrl_reg1); + + val = readl_relaxed(clk->ctrl_reg2); + val &= ~(PLL_POSTDIV1_MASK | PLL_POSTDIV2_MASK); + val |= FIELD_PREP(PLL_POSTDIV1_MASK, 1); + val |= FIELD_PREP(PLL_POSTDIV2_MASK, 1); + writel_relaxed(val, clk->ctrl_reg2); + + /* Last, enable pll */ + val = readl_relaxed(clk->ctrl_reg0); + val &= ~PLL_EN_MASK; + val |= FIELD_PREP(PLL_EN_MASK, 1); + writel_relaxed(val, clk->ctrl_reg0); + + /* Usually the pll will lock in 50us */ + mask = GENMASK(clk->lock_shift + clk->lock_width - 1, clk->lock_shift); + ret = readl_poll_timeout(clk->status_reg, val, val & mask, 1, 50 * 2); + if (ret) + pr_err("failed to lock the pll!\n"); + + return ret; +} + +static unsigned long clk_pll_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct eswin_clk_pll *clk = to_pll_clk(hw); + u64 fbdiv_val, frac_val, tmp; + u32 rem, val; + + val = readl_relaxed(clk->ctrl_reg0); + val &= PLL_FBDIV_MASK; + fbdiv_val = (val >> clk->fbdiv_shift); + + val = readl_relaxed(clk->ctrl_reg1); + val &= PLL_FRAC_MASK; + frac_val = (val >> clk->frac_shift); + + /* rate = 24000000 * (fbdiv + frac / (2 ^ 24)) / 4 */ + tmp = parent_rate * frac_val; + rem = do_div(tmp, BIT(24)); + if (rem) + tmp = parent_rate * fbdiv_val + tmp + 1; + else + tmp = parent_rate * fbdiv_val + tmp; + + do_div(tmp, 4); + + return tmp; +} + +static int clk_pll_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + struct eswin_clk_pll *clk = to_pll_clk(hw); + + req->rate = clamp(req->rate, clk->min_rate, clk->max_rate); + req->min_rate = clk->min_rate; + req->max_rate = clk->max_rate; + + return 0; +} + +int eswin_clk_register_fixed_rate(struct device *dev, + struct eswin_fixed_rate_clock *clks, + int nums, struct eswin_clock_data *data) +{ + struct clk_hw *clk_hw; + int i; + + for (i = 0; i < nums; i++) { + clk_hw = devm_clk_hw_register_fixed_rate(dev, clks[i].name, + NULL, clks[i].flags, + clks[i].rate); + if (IS_ERR(clk_hw)) + return PTR_ERR(clk_hw); + + clks[i].hw = *clk_hw; + data->clk_data.hws[clks[i].id] = clk_hw; + } + + return 0; +} +EXPORT_SYMBOL_GPL(eswin_clk_register_fixed_rate); + +static const struct clk_ops eswin_clk_pll_ops = { + .set_rate = clk_pll_set_rate, + .recalc_rate = clk_pll_recalc_rate, + .determine_rate = clk_pll_determine_rate, +}; + +int eswin_clk_register_pll(struct device *dev, struct eswin_pll_clock *clks, + int nums, struct eswin_clock_data *data) +{ + struct eswin_clk_pll *p_clk = NULL; + struct clk_init_data init; + struct clk_hw *clk_hw; + int i, ret; + + p_clk = devm_kzalloc(dev, sizeof(*p_clk) * nums, GFP_KERNEL); + if (!p_clk) + return -ENOMEM; + + for (i = 0; i < nums; i++) { + p_clk->id = clks[i].id; + p_clk->ctrl_reg0 = data->base + clks[i].ctrl_reg0; + p_clk->fbdiv_shift = clks[i].fbdiv_shift; + + p_clk->ctrl_reg1 = data->base + clks[i].ctrl_reg1; + p_clk->frac_shift = clks[i].frac_shift; + + p_clk->ctrl_reg2 = data->base + clks[i].ctrl_reg2; + + p_clk->status_reg = data->base + clks[i].status_reg; + p_clk->lock_shift = clks[i].lock_shift; + p_clk->lock_width = clks[i].lock_width; + + p_clk->max_rate = clks[i].max_rate; + p_clk->min_rate = clks[i].min_rate; + + init.name = clks[i].name; + init.flags = 0; + init.parent_data = clks[i].parent_data; + init.num_parents = 1; + init.ops = &eswin_clk_pll_ops; + p_clk->hw.init = &init; + + clk_hw = &p_clk->hw; + + ret = devm_clk_hw_register(dev, clk_hw); + if (ret) + return ret; + + clks[i].hw = *clk_hw; + data->clk_data.hws[clks[i].id] = clk_hw; + p_clk++; + } + + return 0; +} +EXPORT_SYMBOL_GPL(eswin_clk_register_pll); + +int eswin_clk_register_fixed_factor(struct device *dev, + struct eswin_fixed_factor_clock *clks, + int nums, struct eswin_clock_data *data) +{ + struct clk_hw *clk_hw; + int i; + + for (i = 0; i < nums; i++) { + clk_hw = devm_clk_hw_register_fixed_factor_index(dev, clks[i].name, + clks[i].parent_data->index, + clks[i].flags, clks[i].mult, + clks[i].div); + + if (IS_ERR(clk_hw)) + return PTR_ERR(clk_hw); + + clks[i].hw = *clk_hw; + data->clk_data.hws[clks[i].id] = clk_hw; + } + + return 0; +} +EXPORT_SYMBOL_GPL(eswin_clk_register_fixed_factor); + +int eswin_clk_register_mux(struct device *dev, struct eswin_mux_clock *clks, + int nums, struct eswin_clock_data *data) +{ + struct clk_hw *clk_hw; + int i; + + for (i = 0; i < nums; i++) { + clk_hw = devm_clk_hw_register_mux_parent_data_table(dev, clks[i].name, + clks[i].parent_data, + clks[i].num_parents, + clks[i].flags, + data->base + clks[i].reg, + clks[i].shift, clks[i].width, + clks[i].mux_flags, + clks[i].table, &data->lock); + + if (IS_ERR(clk_hw)) + return PTR_ERR(clk_hw); + + clks[i].hw = *clk_hw; + data->clk_data.hws[clks[i].id] = clk_hw; + } + + return 0; +} +EXPORT_SYMBOL_GPL(eswin_clk_register_mux); + +static unsigned int _eswin_get_val(unsigned int div, unsigned long flags, + u8 width) +{ + unsigned int maxdiv; + + maxdiv = clk_div_mask(width); + div = div > maxdiv ? maxdiv : div; + + if (flags & ESWIN_PRIV_DIV_MIN_2) + return (div < 2) ? 2 : div; + + return div; +} + +static unsigned int eswin_div_get_val(unsigned long rate, + unsigned long parent_rate, u8 width, + unsigned long flags) +{ + unsigned int div; + + div = DIV_ROUND_UP_ULL((u64)parent_rate, rate); + + return _eswin_get_val(div, flags, width); +} + +static inline struct eswin_divider_clock *to_div_clk(struct clk_hw *hw) +{ + return container_of(hw, struct eswin_divider_clock, hw); +} + +static int clk_div_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct eswin_divider_clock *dclk = to_div_clk(hw); + unsigned long flags; + unsigned int value; + u32 val; + + value = eswin_div_get_val(rate, parent_rate, dclk->width, + dclk->priv_flag); + + spin_lock_irqsave(dclk->lock, flags); + + val = readl_relaxed(dclk->ctrl_reg); + val &= ~(clk_div_mask(dclk->width) << dclk->shift); + val |= (u32)value << dclk->shift; + writel_relaxed(val, dclk->ctrl_reg); + + spin_unlock_irqrestore(dclk->lock, flags); + + return 0; +} + +static unsigned long clk_div_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct eswin_divider_clock *dclk = to_div_clk(hw); + unsigned int div, val; + + val = readl_relaxed(dclk->ctrl_reg) >> dclk->shift; + val &= clk_div_mask(dclk->width); + div = _eswin_get_val(val, dclk->priv_flag, dclk->width); + + return DIV_ROUND_UP_ULL((u64)parent_rate, div); +} + +static int eswin_clk_bestdiv(unsigned long rate, + unsigned long best_parent_rate, u8 width, + unsigned long flags) +{ + unsigned long bestdiv, up_rate, down_rate; + int up, down; + + if (!rate) + rate = 1; + + /* closest round */ + up = DIV_ROUND_UP_ULL((u64)best_parent_rate, rate); + down = best_parent_rate / rate; + + up_rate = DIV_ROUND_UP_ULL((u64)best_parent_rate, up); + down_rate = DIV_ROUND_UP_ULL((u64)best_parent_rate, down); + + bestdiv = (rate - up_rate) <= (down_rate - rate) ? up : down; + + return bestdiv; +} + +static int clk_div_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + struct eswin_divider_clock *dclk = to_div_clk(hw); + int div; + + div = eswin_clk_bestdiv(req->rate, req->best_parent_rate, dclk->width, + dclk->priv_flag); + div = _eswin_get_val(div, dclk->priv_flag, dclk->width); + req->rate = DIV_ROUND_UP_ULL((u64)req->best_parent_rate, div); + + return 0; +} + +static const struct clk_ops eswin_clk_div_ops = { + .set_rate = clk_div_set_rate, + .recalc_rate = clk_div_recalc_rate, + .determine_rate = clk_div_determine_rate, +}; + +struct clk_hw *eswin_register_clkdiv(struct device *dev, unsigned int id, + const char *name, + const struct clk_hw *parent_hw, + unsigned long flags, void __iomem *reg, + u8 shift, u8 width, + unsigned long clk_divider_flags, + unsigned long priv_flag, spinlock_t *lock) +{ + struct eswin_divider_clock *dclk; + struct clk_init_data init; + struct clk_hw *clk_hw; + int ret; + + dclk = devm_kzalloc(dev, sizeof(*dclk), GFP_KERNEL); + if (!dclk) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &eswin_clk_div_ops; + init.flags = flags; + init.parent_hws = &parent_hw; + init.num_parents = 1; + + /* struct clk_divider assignments */ + dclk->id = id; + dclk->ctrl_reg = reg; + dclk->shift = shift; + dclk->width = width; + dclk->div_flags = clk_divider_flags; + dclk->priv_flag = priv_flag; + dclk->lock = lock; + dclk->hw.init = &init; + + /* register the clock */ + clk_hw = &dclk->hw; + ret = devm_clk_hw_register(dev, clk_hw); + if (ret) { + dev_err(dev, "failed to register divider clock!\n"); + return ERR_PTR(ret); + } + + return clk_hw; +} +EXPORT_SYMBOL_GPL(eswin_register_clkdiv); + +int eswin_clk_register_divider(struct device *dev, + struct eswin_divider_clock *clks, + int nums, struct eswin_clock_data *data) +{ + struct clk_hw *clk_hw; + int i; + + for (i = 0; i < nums; i++) { + clk_hw = devm_clk_hw_register_divider_parent_data(dev, clks[i].name, + clks[i].parent_data, + clks[i].flags, + data->base + clks[i].reg, + clks[i].shift, clks[i].width, + clks[i].div_flags, &data->lock); + + if (IS_ERR(clk_hw)) + return PTR_ERR(clk_hw); + + clks[i].hw = *clk_hw; + data->clk_data.hws[clks[i].id] = clk_hw; + } + + return 0; +} +EXPORT_SYMBOL_GPL(eswin_clk_register_divider); + +int eswin_clk_register_gate(struct device *dev, struct eswin_gate_clock *clks, + int nums, struct eswin_clock_data *data) +{ + struct clk_hw *clk_hw; + int i; + + for (i = 0; i < nums; i++) { + clk_hw = devm_clk_hw_register_gate_parent_data(dev, clks[i].name, + clks[i].parent_data, + clks[i].flags, + data->base + clks[i].reg, + clks[i].bit_idx, clks[i].gate_flags, + &data->lock); + + if (IS_ERR(clk_hw)) + return PTR_ERR(clk_hw); + + clks[i].hw = *clk_hw; + data->clk_data.hws[clks[i].id] = clk_hw; + } + + return 0; +} +EXPORT_SYMBOL_GPL(eswin_clk_register_gate); + +int eswin_clk_register_clks(struct device *dev, struct eswin_clk_info *clks, + int nums, struct eswin_clock_data *data) +{ + struct eswin_clk_info *info; + const struct clk_hw *phw = NULL; + struct clk_hw *hw; + int i; + + for (i = 0; i < nums; i++) { + info = &clks[i]; + switch (info->type) { + case CLK_FIXED_FACTOR: { + const struct eswin_fixed_factor_clock *factor; + + factor = &info->data.factor; + phw = data->clk_data.hws[info->pid]; + hw = devm_clk_hw_register_fixed_factor_parent_hw(dev, factor->name, phw, + factor->flags, + factor->mult, + factor->div); + break; + } + case CLK_MUX: { + const struct eswin_mux_clock *mux = &info->data.mux; + + hw = devm_clk_hw_register_mux_parent_data_table(dev, mux->name, + mux->parent_data, + mux->num_parents, + mux->flags, + data->base + mux->reg, + mux->shift, mux->width, + mux->mux_flags, + mux->table, &data->lock); + break; + } + case CLK_DIVIDER: { + const struct eswin_divider_clock *div = &info->data.div; + + phw = data->clk_data.hws[info->pid]; + if (div->priv_flag) + hw = eswin_register_clkdiv(dev, div->id, div->name, phw, + div->flags, data->base + div->reg, + div->shift, div->width, div->div_flags, + div->priv_flag, &data->lock); + else + hw = devm_clk_hw_register_divider_parent_hw(dev, div->name, phw, + div->flags, + data->base + div->reg, + div->shift, div->width, + div->div_flags, + &data->lock); + break; + } + case CLK_GATE: { + const struct eswin_gate_clock *gate = &info->data.gate; + + phw = data->clk_data.hws[info->pid]; + hw = devm_clk_hw_register_gate_parent_hw(dev, gate->name, phw, + gate->flags, + data->base + gate->reg, + gate->bit_idx, gate->gate_flags, + &data->lock); + break; + } + default: + dev_err(dev, "Unidentifiable clock type!\n"); + return -EINVAL; + } + if (IS_ERR(hw)) + return PTR_ERR(hw); + + info->hw = *hw; + data->clk_data.hws[info->id] = hw; + } + + return 0; +} +EXPORT_SYMBOL_GPL(eswin_clk_register_clks); |