[PATCH v4 2/8] clk: starfive: Add system-0 domain PLL clock driver
Changhuang Liang <[email protected]> Sat, 8 Aug 2026 18:50:48 -0700
| Newsgroups | org.kernel.vger.linux-clk,org.infradead.lists.linux-riscv,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
Add system-0 domain PLL clock driver for StarFive JHB100 SoC. Signed-off-by: Changhuang Liang <[email protected]> --- drivers/clk/starfive/Kconfig | 8 + drivers/clk/starfive/Makefile | 1 + .../clk/starfive/clk-starfive-jhb100-pll.c | 535 ++++++++++++++++++ 3 files changed, 544 insertions(+) create mode 100644 drivers/clk/starfive/clk-starfive-jhb100-pll.c diff --git a/drivers/clk/starfive/Kconfig b/drivers/clk/starfive/Kconfig index 852464949334..a39dd22112fa 100644 --- a/drivers/clk/starfive/Kconfig +++ b/drivers/clk/starfive/Kconfig @@ -117,6 +117,14 @@ config CLK_STARFIVE_JHB100_PER3 Say yes here to support the peripheral-3 clock controller on the StarFive JHB100 SoC. +config CLK_STARFIVE_JHB100_PLL + bool "StarFive JHB100 PLL clock support" + depends on ARCH_STARFIVE || COMPILE_TEST + default ARCH_STARFIVE + help + Say yes here to support the PLL clock controller on the + StarFive JHB100 SoC. + config CLK_STARFIVE_JHB100_SYS0 bool "StarFive JHB100 system-0 clock support" depends on ARCH_STARFIVE || COMPILE_TEST diff --git a/drivers/clk/starfive/Makefile b/drivers/clk/starfive/Makefile index f00690f0cdad..547a8c170728 100644 --- a/drivers/clk/starfive/Makefile +++ b/drivers/clk/starfive/Makefile @@ -15,6 +15,7 @@ obj-$(CONFIG_CLK_STARFIVE_JHB100_PER0) += clk-starfive-jhb100-per0.o obj-$(CONFIG_CLK_STARFIVE_JHB100_PER1) += clk-starfive-jhb100-per1.o obj-$(CONFIG_CLK_STARFIVE_JHB100_PER2) += clk-starfive-jhb100-per2.o obj-$(CONFIG_CLK_STARFIVE_JHB100_PER3) += clk-starfive-jhb100-per3.o +obj-$(CONFIG_CLK_STARFIVE_JHB100_PLL) += clk-starfive-jhb100-pll.o obj-$(CONFIG_CLK_STARFIVE_JHB100_SYS0) += clk-starfive-jhb100-sys0.o obj-$(CONFIG_CLK_STARFIVE_JHB100_SYS1) += clk-starfive-jhb100-sys1.o obj-$(CONFIG_CLK_STARFIVE_JHB100_SYS2) += clk-starfive-jhb100-sys2.o diff --git a/drivers/clk/starfive/clk-starfive-jhb100-pll.c b/drivers/clk/starfive/clk-starfive-jhb100-pll.c new file mode 100644 index 000000000000..55d589bc831e --- /dev/null +++ b/drivers/clk/starfive/clk-starfive-jhb100-pll.c @@ -0,0 +1,535 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * StarFive JHB100 PLL Clock Generator Driver + * + * Copyright (C) 2024 StarFive Technology Co., Ltd. + * + * Author: Changhuang Liang <[email protected]> + */ + +#include <linux/bits.h> +#include <linux/clk-provider.h> +#include <linux/debugfs.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/math64.h> +#include <linux/mfd/syscon.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/units.h> + +#include <dt-bindings/clock/starfive,jhb100-crg.h> + +/* this driver expects a 25MHz input frequency from the oscillator */ +#define JHB100_PLL_OSC_RATE (25 * HZ_PER_MHZ) + +/* System-0 domain PLL */ +#define JHB100_PLL2_OFFSET 0x00 +#define JHB100_PLL3_OFFSET 0x0c +#define JHB100_PLL4_OFFSET 0x18 +#define JHB100_PLL5_OFFSET 0x24 + +#define JHB100_PLL_CFG0_OFFSET 0x0 +#define JHB100_PLL_CFG1_OFFSET 0x4 +#define JHB100_PLL_CFG2_OFFSET 0x8 + +#define JHB100_PLLX_CFG0(offset) ((offset) + JHB100_PLL_CFG0_OFFSET) +/* fbdiv value should be 16 to 4095 */ +#define JHB100_PLL_FBDIV GENMASK(13, 2) +#define JHB100_PLL_FBDIV_SHIFT 2 +#define JHB100_PLL_FOUTPOSTDIV_EN BIT(14) +#define JHB100_PLL_FOUTPOSTDIV_EN_SHIFT 14 +#define JHB100_PLL_FOUTVCOP_EN BIT(16) +#define JHB100_PLL_FOUTVCOP_EN_SHIFT 16 + +#define JHB100_PLLX_CFG1(offset) ((offset) + JHB100_PLL_CFG1_OFFSET) +/* frac value should be decimals multiplied by 2^24 */ +#define JHB100_PLL_FRAC GENMASK(23, 0) +#define JHB100_PLL_FRAC_SHIFT 0 +#define JHB100_PLL_LOCK BIT(24) +#define JHB100_PLL_LOCK_SHIFT 24 + +#define JHB100_PLLX_CFG2(offset) ((offset) + JHB100_PLL_CFG2_OFFSET) +#define JHB100_PLL_PD BIT(13) +#define JHB100_PLL_PD_SHIFT 13 +#define JHB100_PLL_POSTDIV GENMASK(15, 14) +#define JHB100_PLL_POSTDIV_SHIFT 14 +#define JHB100_PLL_REFDIV GENMASK(23, 18) +#define JHB100_PLL_REFDIV_SHIFT 18 + +#define JHB100_PLL_TIMEOUT_US 1000 +#define JHB100_PLL_INTERVAL_US 100 + +struct jhb100_pll_preset { + unsigned long freq; + u32 frac; /* frac value should be decimals multiplied by 2^24 */ + unsigned fbdiv : 12; /* fbdiv value should be 16 to 4095 */ + unsigned refdiv : 6; + unsigned postdiv : 2; + unsigned foutpostdiv_en : 1; + unsigned foutvcop_en : 1; +}; + +struct jhb100_pll_info { + char *name; + const struct jhb100_pll_preset *presets; + unsigned int npresets; + unsigned long flag; + u8 offset; + bool continuous; +}; + +#define _JHB100_PLL(_idx, _name, _presets, _npresets, _offset, _flag, _cont) \ + [_idx] = { \ + .name = _name, \ + .offset = _offset, \ + .presets = _presets, \ + .npresets = _npresets, \ + .flag = _flag, \ + .continuous = _cont, \ + } + +#define JHB100_PLL(idx, name, presets, npresets, offset, cont) \ + _JHB100_PLL(idx, name, presets, npresets, offset, 0, cont) + +struct jhb100_pll_match_data { + const struct jhb100_pll_info *pll_info; + int num_pll; +}; + +struct jhb100_pll_data { + struct clk_hw hw; + unsigned int idx; +}; + +struct jhb100_pll_priv { + struct device *dev; + struct regmap *regmap; + const struct jhb100_pll_match_data *match_data; + struct jhb100_pll_data pll[]; +}; + +struct jhb100_pll_regvals { + u32 fbdiv; + u32 frac; + u32 postdiv; + u32 refdiv; + bool foutpostdiv_en; + bool foutvcop_en; +}; + +static struct jhb100_pll_data *jhb100_pll_data_from(struct clk_hw *hw) +{ + return container_of(hw, struct jhb100_pll_data, hw); +} + +static struct jhb100_pll_priv *jhb100_pll_priv_from(struct jhb100_pll_data *pll) +{ + return container_of(pll, struct jhb100_pll_priv, pll[pll->idx]); +} + +static int jhb100_pll_prepare(struct clk_hw *hw) +{ + struct jhb100_pll_data *pll = jhb100_pll_data_from(hw); + struct jhb100_pll_priv *priv = jhb100_pll_priv_from(pll); + const struct jhb100_pll_info *info = &priv->match_data->pll_info[pll->idx]; + + return regmap_update_bits(priv->regmap, JHB100_PLLX_CFG2(info->offset), + JHB100_PLL_PD, 0); +} + +static void jhb100_pll_unprepare(struct clk_hw *hw) +{ + struct jhb100_pll_data *pll = jhb100_pll_data_from(hw); + struct jhb100_pll_priv *priv = jhb100_pll_priv_from(pll); + const struct jhb100_pll_info *info = &priv->match_data->pll_info[pll->idx]; + + regmap_update_bits(priv->regmap, JHB100_PLLX_CFG2(info->offset), + JHB100_PLL_PD, BIT(JHB100_PLL_PD_SHIFT)); +} + +static int jhb100_pll_is_prepared(struct clk_hw *hw) +{ + struct jhb100_pll_data *pll = jhb100_pll_data_from(hw); + struct jhb100_pll_priv *priv = jhb100_pll_priv_from(pll); + const struct jhb100_pll_info *info = &priv->match_data->pll_info[pll->idx]; + u32 val; + int ret; + + ret = regmap_read(priv->regmap, JHB100_PLLX_CFG2(info->offset), &val); + if (ret) + return ret; + + return !(val & JHB100_PLL_PD); +} + +static int jhb100_pll_regvals_get(struct regmap *regmap, + const struct jhb100_pll_info *info, + struct jhb100_pll_regvals *val) +{ + u32 value; + int ret; + + ret = regmap_read(regmap, JHB100_PLLX_CFG0(info->offset), &value); + if (ret) + return ret; + + val->fbdiv = (value & JHB100_PLL_FBDIV) >> JHB100_PLL_FBDIV_SHIFT; + val->foutpostdiv_en = !!((value & JHB100_PLL_FOUTPOSTDIV_EN) >> + JHB100_PLL_FOUTPOSTDIV_EN_SHIFT); + val->foutvcop_en = !!((value & JHB100_PLL_FOUTVCOP_EN) >> + JHB100_PLL_FOUTVCOP_EN_SHIFT); + + ret = regmap_read(regmap, JHB100_PLLX_CFG1(info->offset), &value); + if (ret) + return ret; + + val->frac = (value & JHB100_PLL_FRAC) >> JHB100_PLL_FRAC_SHIFT; + + ret = regmap_read(regmap, JHB100_PLLX_CFG2(info->offset), &value); + if (ret) + return ret; + + val->postdiv = (value & JHB100_PLL_POSTDIV) >> JHB100_PLL_POSTDIV_SHIFT; + val->refdiv = (value & JHB100_PLL_REFDIV) >> JHB100_PLL_REFDIV_SHIFT; + + return 0; +} + +static unsigned long jhb100_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) +{ + struct jhb100_pll_data *pll = jhb100_pll_data_from(hw); + struct jhb100_pll_priv *priv = jhb100_pll_priv_from(pll); + struct jhb100_pll_regvals val; + u32 power = 0; + u64 rate; + int ret; + + ret = jhb100_pll_regvals_get(priv->regmap, &priv->match_data->pll_info[pll->idx], &val); + if (ret) + return 0; + + /* + * + * if (foutvcop_en) + * rate = parent * (fbdiv + frac / 2^24) / refdiv + * + * if (foutpostdiv_en) + * rate = parent * (fbdiv + frac / 2^24) / refdiv / 2^(postdiv + 1) + * + * parent * (fbdiv + frac / 2^24) = parent * fbdiv + parent * frac / 2^24 + */ + + if (!!val.foutvcop_en == !!val.foutpostdiv_en || !val.refdiv) + return 0; + + rate = mul_u32_u32(parent_rate, val.frac) >> 24; + + if (val.foutpostdiv_en) + power = val.postdiv + 1; + + rate += mul_u32_u32(parent_rate, val.fbdiv); + rate = div_u64(rate, (u64)val.refdiv << power); + + return rate; +} + +static int jhb100_pll_determine_rate(struct clk_hw *hw, struct clk_rate_request *req) +{ + struct jhb100_pll_data *pll = jhb100_pll_data_from(hw); + struct jhb100_pll_priv *priv = jhb100_pll_priv_from(pll); + const struct jhb100_pll_info *info = &priv->match_data->pll_info[pll->idx]; + const struct jhb100_pll_preset *selected = &info->presets[0]; + unsigned int idx; + + /* if the parent rate doesn't match our expectations the presets won't work */ + if (req->best_parent_rate != JHB100_PLL_OSC_RATE) { + req->rate = jhb100_pll_recalc_rate(hw, req->best_parent_rate); + return 0; + } + + /* continuous means support any rate */ + if (info->continuous) + return 0; + + /* find highest rate lower or equal to the requested rate */ + for (idx = 1; idx < info->npresets; idx++) { + const struct jhb100_pll_preset *val = &info->presets[idx]; + + if (req->rate < val->freq) + break; + + selected = val; + } + + req->rate = selected->freq; + + return 0; +} + +static int jhb100_pll_set_preset(struct clk_hw *hw, const struct jhb100_pll_preset *val) +{ + struct jhb100_pll_data *pll = jhb100_pll_data_from(hw); + struct jhb100_pll_priv *priv = jhb100_pll_priv_from(pll); + const struct jhb100_pll_info *info = &priv->match_data->pll_info[pll->idx]; + unsigned int value, cfg; + int ret; + + cfg = ((u32)val->fbdiv << JHB100_PLL_FBDIV_SHIFT) | + ((u32)val->foutpostdiv_en << JHB100_PLL_FOUTPOSTDIV_EN_SHIFT) | + ((u32)val->foutvcop_en << JHB100_PLL_FOUTVCOP_EN_SHIFT); + + ret = regmap_update_bits(priv->regmap, JHB100_PLLX_CFG0(info->offset), + JHB100_PLL_FBDIV | JHB100_PLL_FOUTPOSTDIV_EN | + JHB100_PLL_FOUTVCOP_EN, cfg); + if (ret) + return ret; + + ret = regmap_update_bits(priv->regmap, JHB100_PLLX_CFG1(info->offset), JHB100_PLL_FRAC, + val->frac << JHB100_PLL_FRAC_SHIFT); + if (ret) + return ret; + + cfg = ((u32)val->refdiv << JHB100_PLL_REFDIV_SHIFT) | + ((u32)val->postdiv << JHB100_PLL_POSTDIV_SHIFT); + + ret = regmap_update_bits(priv->regmap, JHB100_PLLX_CFG2(info->offset), + JHB100_PLL_REFDIV | JHB100_PLL_POSTDIV, cfg); + if (ret) + return ret; + + /* waiting for PLL to lock */ + return regmap_read_poll_timeout(priv->regmap, JHB100_PLLX_CFG1(info->offset), + value, value & JHB100_PLL_LOCK, + JHB100_PLL_INTERVAL_US, + JHB100_PLL_TIMEOUT_US); +} + +static int jhb100_pll_rate_to_preset(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct jhb100_pll_preset val = { + .refdiv = 1, + .postdiv = 3, + .foutpostdiv_en = 1, + .foutvcop_en = 0, + }; + unsigned int power = 0; + u64 fbdiv_24, t; + u32 fbdiv; + + if (val.foutpostdiv_en) + power = val.postdiv + 1; + + t = (u64)val.refdiv << power; + t *= rate; + + fbdiv = div64_ul(t, parent_rate); + if (fbdiv < 16 || fbdiv > 4095) + return -EINVAL; + val.fbdiv = fbdiv; + + fbdiv_24 = div64_ul(t << 24, parent_rate); + val.frac = fbdiv_24 - ((u64)fbdiv << 24); + + return jhb100_pll_set_preset(hw, &val); +} + +static int jhb100_pll_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct jhb100_pll_data *pll = jhb100_pll_data_from(hw); + struct jhb100_pll_priv *priv = jhb100_pll_priv_from(pll); + const struct jhb100_pll_info *info = &priv->match_data->pll_info[pll->idx]; + const struct jhb100_pll_preset *val; + unsigned int idx; + + /* if the parent rate doesn't match our expectations the presets won't work */ + if (parent_rate != JHB100_PLL_OSC_RATE) + return -EINVAL; + + if (info->continuous) + return jhb100_pll_rate_to_preset(hw, rate, parent_rate); + + for (idx = 0, val = &info->presets[0]; idx < info->npresets; idx++, val++) { + if (val->freq == rate) + return jhb100_pll_set_preset(hw, val); + } + return -EINVAL; +} + +#ifdef CONFIG_DEBUG_FS +static int jhb100_pll_registers_read(struct seq_file *s, void *unused) +{ + struct jhb100_pll_data *pll = s->private; + struct jhb100_pll_priv *priv = jhb100_pll_priv_from(pll); + struct jhb100_pll_regvals val; + int ret; + + ret = jhb100_pll_regvals_get(priv->regmap, &priv->match_data->pll_info[pll->idx], &val); + if (ret) + return ret; + + seq_printf(s, "fbdiv=%u\n" + "frac=%u\n" + "refdiv=%u\n" + "postdiv=%u\n" + "foutpostdiv_en=%u\n" + "foutvcop_en=%u\n", + val.fbdiv, val.frac, val.refdiv, val.postdiv, + val.foutpostdiv_en, val.foutvcop_en); + + return 0; +} + +static int jhb100_pll_registers_open(struct inode *inode, struct file *f) +{ + return single_open(f, jhb100_pll_registers_read, inode->i_private); +} + +static const struct file_operations jhb100_pll_registers_ops = { + .owner = THIS_MODULE, + .open = jhb100_pll_registers_open, + .release = single_release, + .read = seq_read, + .llseek = seq_lseek +}; + +static void jhb100_pll_debug_init(struct clk_hw *hw, struct dentry *dentry) +{ + struct jhb100_pll_data *pll = jhb100_pll_data_from(hw); + + debugfs_create_file("registers", 0400, dentry, pll, + &jhb100_pll_registers_ops); +} +#else +#define jhb100_pll_debug_init NULL +#endif + +static const struct clk_ops jhb100_pll_ops = { + .prepare = jhb100_pll_prepare, + .unprepare = jhb100_pll_unprepare, + .is_prepared = jhb100_pll_is_prepared, + .recalc_rate = jhb100_pll_recalc_rate, + .determine_rate = jhb100_pll_determine_rate, + .set_rate = jhb100_pll_set_rate, + .debug_init = jhb100_pll_debug_init, +}; + +static struct clk_hw *jhb100_pll_get(struct of_phandle_args *clkspec, void *data) +{ + struct jhb100_pll_priv *priv = data; + unsigned int idx = clkspec->args[0]; + + if (idx < priv->match_data->num_pll) + return &priv->pll[idx].hw; + + return ERR_PTR(-EINVAL); +} + +static int jhb100_pll_probe(struct platform_device *pdev) +{ + const struct jhb100_pll_match_data *match_data; + struct jhb100_pll_priv *priv; + unsigned int idx; + int ret; + + match_data = of_device_get_match_data(&pdev->dev); + if (!match_data) + return -EINVAL; + + priv = devm_kzalloc(&pdev->dev, + struct_size(priv, pll, match_data->num_pll), + GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->match_data = match_data; + priv->dev = &pdev->dev; + priv->regmap = syscon_node_to_regmap(priv->dev->of_node); + if (IS_ERR(priv->regmap)) + return PTR_ERR(priv->regmap); + + for (idx = 0; idx < match_data->num_pll; idx++) { + struct clk_parent_data parents = { + .index = 0, + }; + struct clk_init_data init = { + .name = match_data->pll_info[idx].name, + .ops = &jhb100_pll_ops, + .parent_data = &parents, + .num_parents = 1, + .flags = match_data->pll_info[idx].flag, + }; + struct jhb100_pll_data *pll = &priv->pll[idx]; + + pll->hw.init = &init; + pll->idx = idx; + + ret = devm_clk_hw_register(&pdev->dev, &pll->hw); + if (ret) + return ret; + } + + return devm_of_clk_add_hw_provider(&pdev->dev, jhb100_pll_get, priv); +} + +static const struct jhb100_pll_preset jhb100_pll2_presets[] = { + { + .freq = 903168000, + .fbdiv = 72, + .frac = 4252017, + .refdiv = 1, + .postdiv = 0, + .foutpostdiv_en = 1, + .foutvcop_en = 0, + }, +}; + +static const struct jhb100_pll_preset jhb100_pll3_presets[] = { + { + .freq = 800000000, + .fbdiv = 64, + .frac = 0, + .refdiv = 1, + .postdiv = 0, + .foutpostdiv_en = 1, + .foutvcop_en = 0, + }, +}; + +static const struct jhb100_pll_info jhb100_sys0_pll_info[] = { + JHB100_PLL(JHB100_SYS0PLL_PLL2_OUT, "pll2_out", jhb100_pll2_presets, + ARRAY_SIZE(jhb100_pll2_presets), JHB100_PLL2_OFFSET, false), + _JHB100_PLL(JHB100_SYS0PLL_PLL3_OUT, "pll3_out", jhb100_pll3_presets, + ARRAY_SIZE(jhb100_pll3_presets), JHB100_PLL3_OFFSET, + CLK_IS_CRITICAL, false), + _JHB100_PLL(JHB100_SYS0PLL_PLL4_OUT, "pll4_out", NULL, 0, + JHB100_PLL4_OFFSET, CLK_IGNORE_UNUSED, true), + _JHB100_PLL(JHB100_SYS0PLL_PLL5_OUT, "pll5_out", NULL, 0, + JHB100_PLL5_OFFSET, CLK_IGNORE_UNUSED, true), +}; + +static const struct jhb100_pll_match_data jhb100_sys0_pll = { + .pll_info = jhb100_sys0_pll_info, + .num_pll = ARRAY_SIZE(jhb100_sys0_pll_info), +}; + +static const struct of_device_id jhb100_pll_match[] = { + { + .compatible = "starfive,jhb100-sys0-syscon", + .data = &jhb100_sys0_pll, + }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, jhb100_pll_match); + +static struct platform_driver jhb100_pll_driver = { + .probe = jhb100_pll_probe, + .driver = { + .name = "clk-starfive-jhb100-pll", + .of_match_table = jhb100_pll_match, + .suppress_bind_attrs = true, + }, +}; +builtin_platform_driver(jhb100_pll_driver); -- 2.25.1