diff options
Diffstat (limited to 'drivers/clk/mediatek/clk-pll.c')
-rw-r--r-- | drivers/clk/mediatek/clk-pll.c | 449 |
1 files changed, 449 insertions, 0 deletions
diff --git a/drivers/clk/mediatek/clk-pll.c b/drivers/clk/mediatek/clk-pll.c new file mode 100644 index 0000000000..513ab6b1b3 --- /dev/null +++ b/drivers/clk/mediatek/clk-pll.c @@ -0,0 +1,449 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2014 MediaTek Inc. + * Author: James Liao <jamesjj.liao@mediatek.com> + */ + +#include <linux/clk-provider.h> +#include <linux/container_of.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/slab.h> + +#include "clk-pll.h" + +#define MHZ (1000 * 1000) + +#define REG_CON0 0 +#define REG_CON1 4 + +#define CON0_BASE_EN BIT(0) +#define CON0_PWR_ON BIT(0) +#define CON0_ISO_EN BIT(1) +#define PCW_CHG_MASK BIT(31) + +#define AUDPLL_TUNER_EN BIT(31) + +/* default 7 bits integer, can be overridden with pcwibits. */ +#define INTEGER_BITS 7 + +int mtk_pll_is_prepared(struct clk_hw *hw) +{ + struct mtk_clk_pll *pll = to_mtk_clk_pll(hw); + + return (readl(pll->en_addr) & BIT(pll->data->pll_en_bit)) != 0; +} + +static unsigned long __mtk_pll_recalc_rate(struct mtk_clk_pll *pll, u32 fin, + u32 pcw, int postdiv) +{ + int pcwbits = pll->data->pcwbits; + int pcwfbits = 0; + int ibits; + u64 vco; + u8 c = 0; + + /* The fractional part of the PLL divider. */ + ibits = pll->data->pcwibits ? pll->data->pcwibits : INTEGER_BITS; + if (pcwbits > ibits) + pcwfbits = pcwbits - ibits; + + vco = (u64)fin * pcw; + + if (pcwfbits && (vco & GENMASK(pcwfbits - 1, 0))) + c = 1; + + vco >>= pcwfbits; + + if (c) + vco++; + + return ((unsigned long)vco + postdiv - 1) / postdiv; +} + +static void __mtk_pll_tuner_enable(struct mtk_clk_pll *pll) +{ + u32 r; + + if (pll->tuner_en_addr) { + r = readl(pll->tuner_en_addr) | BIT(pll->data->tuner_en_bit); + writel(r, pll->tuner_en_addr); + } else if (pll->tuner_addr) { + r = readl(pll->tuner_addr) | AUDPLL_TUNER_EN; + writel(r, pll->tuner_addr); + } +} + +static void __mtk_pll_tuner_disable(struct mtk_clk_pll *pll) +{ + u32 r; + + if (pll->tuner_en_addr) { + r = readl(pll->tuner_en_addr) & ~BIT(pll->data->tuner_en_bit); + writel(r, pll->tuner_en_addr); + } else if (pll->tuner_addr) { + r = readl(pll->tuner_addr) & ~AUDPLL_TUNER_EN; + writel(r, pll->tuner_addr); + } +} + +static void mtk_pll_set_rate_regs(struct mtk_clk_pll *pll, u32 pcw, + int postdiv) +{ + u32 chg, val; + + /* disable tuner */ + __mtk_pll_tuner_disable(pll); + + /* set postdiv */ + val = readl(pll->pd_addr); + val &= ~(POSTDIV_MASK << pll->data->pd_shift); + val |= (ffs(postdiv) - 1) << pll->data->pd_shift; + + /* postdiv and pcw need to set at the same time if on same register */ + if (pll->pd_addr != pll->pcw_addr) { + writel(val, pll->pd_addr); + val = readl(pll->pcw_addr); + } + + /* set pcw */ + val &= ~GENMASK(pll->data->pcw_shift + pll->data->pcwbits - 1, + pll->data->pcw_shift); + val |= pcw << pll->data->pcw_shift; + writel(val, pll->pcw_addr); + chg = readl(pll->pcw_chg_addr) | PCW_CHG_MASK; + writel(chg, pll->pcw_chg_addr); + if (pll->tuner_addr) + writel(val + 1, pll->tuner_addr); + + /* restore tuner_en */ + __mtk_pll_tuner_enable(pll); + + udelay(20); +} + +/* + * mtk_pll_calc_values - calculate good values for a given input frequency. + * @pll: The pll + * @pcw: The pcw value (output) + * @postdiv: The post divider (output) + * @freq: The desired target frequency + * @fin: The input frequency + * + */ +void mtk_pll_calc_values(struct mtk_clk_pll *pll, u32 *pcw, u32 *postdiv, + u32 freq, u32 fin) +{ + unsigned long fmin = pll->data->fmin ? pll->data->fmin : (1000 * MHZ); + const struct mtk_pll_div_table *div_table = pll->data->div_table; + u64 _pcw; + int ibits; + u32 val; + + if (freq > pll->data->fmax) + freq = pll->data->fmax; + + if (div_table) { + if (freq > div_table[0].freq) + freq = div_table[0].freq; + + for (val = 0; div_table[val + 1].freq != 0; val++) { + if (freq > div_table[val + 1].freq) + break; + } + *postdiv = 1 << val; + } else { + for (val = 0; val < 5; val++) { + *postdiv = 1 << val; + if ((u64)freq * *postdiv >= fmin) + break; + } + } + + /* _pcw = freq * postdiv / fin * 2^pcwfbits */ + ibits = pll->data->pcwibits ? pll->data->pcwibits : INTEGER_BITS; + _pcw = ((u64)freq << val) << (pll->data->pcwbits - ibits); + do_div(_pcw, fin); + + *pcw = (u32)_pcw; +} + +int mtk_pll_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct mtk_clk_pll *pll = to_mtk_clk_pll(hw); + u32 pcw = 0; + u32 postdiv; + + mtk_pll_calc_values(pll, &pcw, &postdiv, rate, parent_rate); + mtk_pll_set_rate_regs(pll, pcw, postdiv); + + return 0; +} + +unsigned long mtk_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) +{ + struct mtk_clk_pll *pll = to_mtk_clk_pll(hw); + u32 postdiv; + u32 pcw; + + postdiv = (readl(pll->pd_addr) >> pll->data->pd_shift) & POSTDIV_MASK; + postdiv = 1 << postdiv; + + pcw = readl(pll->pcw_addr) >> pll->data->pcw_shift; + pcw &= GENMASK(pll->data->pcwbits - 1, 0); + + return __mtk_pll_recalc_rate(pll, parent_rate, pcw, postdiv); +} + +long mtk_pll_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + struct mtk_clk_pll *pll = to_mtk_clk_pll(hw); + u32 pcw = 0; + int postdiv; + + mtk_pll_calc_values(pll, &pcw, &postdiv, rate, *prate); + + return __mtk_pll_recalc_rate(pll, *prate, pcw, postdiv); +} + +int mtk_pll_prepare(struct clk_hw *hw) +{ + struct mtk_clk_pll *pll = to_mtk_clk_pll(hw); + u32 r; + + r = readl(pll->pwr_addr) | CON0_PWR_ON; + writel(r, pll->pwr_addr); + udelay(1); + + r = readl(pll->pwr_addr) & ~CON0_ISO_EN; + writel(r, pll->pwr_addr); + udelay(1); + + r = readl(pll->en_addr) | BIT(pll->data->pll_en_bit); + writel(r, pll->en_addr); + + if (pll->data->en_mask) { + r = readl(pll->base_addr + REG_CON0) | pll->data->en_mask; + writel(r, pll->base_addr + REG_CON0); + } + + __mtk_pll_tuner_enable(pll); + + udelay(20); + + if (pll->data->flags & HAVE_RST_BAR) { + r = readl(pll->base_addr + REG_CON0); + r |= pll->data->rst_bar_mask; + writel(r, pll->base_addr + REG_CON0); + } + + return 0; +} + +void mtk_pll_unprepare(struct clk_hw *hw) +{ + struct mtk_clk_pll *pll = to_mtk_clk_pll(hw); + u32 r; + + if (pll->data->flags & HAVE_RST_BAR) { + r = readl(pll->base_addr + REG_CON0); + r &= ~pll->data->rst_bar_mask; + writel(r, pll->base_addr + REG_CON0); + } + + __mtk_pll_tuner_disable(pll); + + if (pll->data->en_mask) { + r = readl(pll->base_addr + REG_CON0) & ~pll->data->en_mask; + writel(r, pll->base_addr + REG_CON0); + } + + r = readl(pll->en_addr) & ~BIT(pll->data->pll_en_bit); + writel(r, pll->en_addr); + + r = readl(pll->pwr_addr) | CON0_ISO_EN; + writel(r, pll->pwr_addr); + + r = readl(pll->pwr_addr) & ~CON0_PWR_ON; + writel(r, pll->pwr_addr); +} + +const struct clk_ops mtk_pll_ops = { + .is_prepared = mtk_pll_is_prepared, + .prepare = mtk_pll_prepare, + .unprepare = mtk_pll_unprepare, + .recalc_rate = mtk_pll_recalc_rate, + .round_rate = mtk_pll_round_rate, + .set_rate = mtk_pll_set_rate, +}; + +struct clk_hw *mtk_clk_register_pll_ops(struct mtk_clk_pll *pll, + const struct mtk_pll_data *data, + void __iomem *base, + const struct clk_ops *pll_ops) +{ + struct clk_init_data init = {}; + int ret; + const char *parent_name = "clk26m"; + + pll->base_addr = base + data->reg; + pll->pwr_addr = base + data->pwr_reg; + pll->pd_addr = base + data->pd_reg; + pll->pcw_addr = base + data->pcw_reg; + if (data->pcw_chg_reg) + pll->pcw_chg_addr = base + data->pcw_chg_reg; + else + pll->pcw_chg_addr = pll->base_addr + REG_CON1; + if (data->tuner_reg) + pll->tuner_addr = base + data->tuner_reg; + if (data->tuner_en_reg || data->tuner_en_bit) + pll->tuner_en_addr = base + data->tuner_en_reg; + if (data->en_reg) + pll->en_addr = base + data->en_reg; + else + pll->en_addr = pll->base_addr + REG_CON0; + pll->hw.init = &init; + pll->data = data; + + init.name = data->name; + init.flags = (data->flags & PLL_AO) ? CLK_IS_CRITICAL : 0; + init.ops = pll_ops; + if (data->parent_name) + init.parent_names = &data->parent_name; + else + init.parent_names = &parent_name; + init.num_parents = 1; + + ret = clk_hw_register(NULL, &pll->hw); + + if (ret) + return ERR_PTR(ret); + + return &pll->hw; +} + +struct clk_hw *mtk_clk_register_pll(const struct mtk_pll_data *data, + void __iomem *base) +{ + struct mtk_clk_pll *pll; + struct clk_hw *hw; + + pll = kzalloc(sizeof(*pll), GFP_KERNEL); + if (!pll) + return ERR_PTR(-ENOMEM); + + hw = mtk_clk_register_pll_ops(pll, data, base, &mtk_pll_ops); + if (IS_ERR(hw)) + kfree(pll); + + return hw; +} + +void mtk_clk_unregister_pll(struct clk_hw *hw) +{ + struct mtk_clk_pll *pll; + + if (!hw) + return; + + pll = to_mtk_clk_pll(hw); + + clk_hw_unregister(hw); + kfree(pll); +} + +int mtk_clk_register_plls(struct device_node *node, + const struct mtk_pll_data *plls, int num_plls, + struct clk_hw_onecell_data *clk_data) +{ + void __iomem *base; + int i; + struct clk_hw *hw; + + base = of_iomap(node, 0); + if (!base) { + pr_err("%s(): ioremap failed\n", __func__); + return -EINVAL; + } + + for (i = 0; i < num_plls; i++) { + const struct mtk_pll_data *pll = &plls[i]; + + if (!IS_ERR_OR_NULL(clk_data->hws[pll->id])) { + pr_warn("%pOF: Trying to register duplicate clock ID: %d\n", + node, pll->id); + continue; + } + + hw = mtk_clk_register_pll(pll, base); + + if (IS_ERR(hw)) { + pr_err("Failed to register clk %s: %pe\n", pll->name, + hw); + goto err; + } + + clk_data->hws[pll->id] = hw; + } + + return 0; + +err: + while (--i >= 0) { + const struct mtk_pll_data *pll = &plls[i]; + + mtk_clk_unregister_pll(clk_data->hws[pll->id]); + clk_data->hws[pll->id] = ERR_PTR(-ENOENT); + } + + iounmap(base); + + return PTR_ERR(hw); +} +EXPORT_SYMBOL_GPL(mtk_clk_register_plls); + +__iomem void *mtk_clk_pll_get_base(struct clk_hw *hw, + const struct mtk_pll_data *data) +{ + struct mtk_clk_pll *pll = to_mtk_clk_pll(hw); + + return pll->base_addr - data->reg; +} + +void mtk_clk_unregister_plls(const struct mtk_pll_data *plls, int num_plls, + struct clk_hw_onecell_data *clk_data) +{ + __iomem void *base = NULL; + int i; + + if (!clk_data) + return; + + for (i = num_plls; i > 0; i--) { + const struct mtk_pll_data *pll = &plls[i - 1]; + + if (IS_ERR_OR_NULL(clk_data->hws[pll->id])) + continue; + + /* + * This is quite ugly but unfortunately the clks don't have + * any device tied to them, so there's no place to store the + * pointer to the I/O region base address. We have to fetch + * it from one of the registered clks. + */ + base = mtk_clk_pll_get_base(clk_data->hws[pll->id], pll); + + mtk_clk_unregister_pll(clk_data->hws[pll->id]); + clk_data->hws[pll->id] = ERR_PTR(-ENOENT); + } + + iounmap(base); +} +EXPORT_SYMBOL_GPL(mtk_clk_unregister_plls); + +MODULE_LICENSE("GPL"); |