| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Toshiba Visconti PLL driver |
| * |
| * Copyright (c) 2021 TOSHIBA CORPORATION |
| * Copyright (c) 2021 Toshiba Electronic Devices & Storage Corporation |
| * |
| * Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp> |
| */ |
| |
| #include <linux/bitfield.h> |
| #include <linux/clk-provider.h> |
| #include <linux/delay.h> |
| #include <linux/slab.h> |
| #include <linux/io.h> |
| |
| #include "pll.h" |
| |
| struct visconti_pll { |
| struct clk_hw hw; |
| void __iomem *pll_base; |
| spinlock_t *lock; |
| unsigned long flags; |
| const struct visconti_pll_rate_table *rate_table; |
| size_t rate_count; |
| struct visconti_pll_provider *ctx; |
| }; |
| |
| #define PLL_CONF_REG 0x0000 |
| #define PLL_CTRL_REG 0x0004 |
| #define PLL_FRACMODE_REG 0x0010 |
| #define PLL_INTIN_REG 0x0014 |
| #define PLL_FRACIN_REG 0x0018 |
| #define PLL_REFDIV_REG 0x001c |
| #define PLL_POSTDIV_REG 0x0020 |
| |
| #define PLL_CONFIG_SEL BIT(0) |
| #define PLL_PLLEN BIT(4) |
| #define PLL_BYPASS BIT(16) |
| #define PLL_INTIN_MASK GENMASK(11, 0) |
| #define PLL_FRACIN_MASK GENMASK(23, 0) |
| #define PLL_REFDIV_MASK GENMASK(5, 0) |
| #define PLL_POSTDIV_MASK GENMASK(2, 0) |
| |
| #define PLL0_FRACMODE_DACEN BIT(4) |
| #define PLL0_FRACMODE_DSMEN BIT(0) |
| |
| #define PLL_CREATE_FRACMODE(table) (table->dacen << 4 | table->dsmen) |
| #define PLL_CREATE_OSTDIV(table) (table->postdiv2 << 4 | table->postdiv1) |
| |
| static inline struct visconti_pll *to_visconti_pll(struct clk_hw *hw) |
| { |
| return container_of(hw, struct visconti_pll, hw); |
| } |
| |
| static void visconti_pll_get_params(struct visconti_pll *pll, |
| struct visconti_pll_rate_table *rate_table) |
| { |
| u32 postdiv, val; |
| |
| val = readl(pll->pll_base + PLL_FRACMODE_REG); |
| |
| rate_table->dacen = FIELD_GET(PLL0_FRACMODE_DACEN, val); |
| rate_table->dsmen = FIELD_GET(PLL0_FRACMODE_DSMEN, val); |
| |
| rate_table->fracin = readl(pll->pll_base + PLL_FRACIN_REG) & PLL_FRACIN_MASK; |
| rate_table->intin = readl(pll->pll_base + PLL_INTIN_REG) & PLL_INTIN_MASK; |
| rate_table->refdiv = readl(pll->pll_base + PLL_REFDIV_REG) & PLL_REFDIV_MASK; |
| |
| postdiv = readl(pll->pll_base + PLL_POSTDIV_REG); |
| rate_table->postdiv1 = postdiv & PLL_POSTDIV_MASK; |
| rate_table->postdiv2 = (postdiv >> 4) & PLL_POSTDIV_MASK; |
| } |
| |
| static const struct visconti_pll_rate_table *visconti_get_pll_settings(struct visconti_pll *pll, |
| unsigned long rate) |
| { |
| const struct visconti_pll_rate_table *rate_table = pll->rate_table; |
| int i; |
| |
| for (i = 0; i < pll->rate_count; i++) |
| if (rate == rate_table[i].rate) |
| return &rate_table[i]; |
| |
| return NULL; |
| } |
| |
| static unsigned long visconti_get_pll_rate_from_data(struct visconti_pll *pll, |
| const struct visconti_pll_rate_table *rate) |
| { |
| const struct visconti_pll_rate_table *rate_table = pll->rate_table; |
| int i; |
| |
| for (i = 0; i < pll->rate_count; i++) |
| if (memcmp(&rate_table[i].dacen, &rate->dacen, |
| sizeof(*rate) - sizeof(unsigned long)) == 0) |
| return rate_table[i].rate; |
| |
| /* set default */ |
| return rate_table[0].rate; |
| } |
| |
| static long visconti_pll_round_rate(struct clk_hw *hw, |
| unsigned long rate, unsigned long *prate) |
| { |
| struct visconti_pll *pll = to_visconti_pll(hw); |
| const struct visconti_pll_rate_table *rate_table = pll->rate_table; |
| int i; |
| |
| /* Assumming rate_table is in descending order */ |
| for (i = 0; i < pll->rate_count; i++) |
| if (rate >= rate_table[i].rate) |
| return rate_table[i].rate; |
| |
| /* return minimum supported value */ |
| return rate_table[i - 1].rate; |
| } |
| |
| static unsigned long visconti_pll_recalc_rate(struct clk_hw *hw, |
| unsigned long parent_rate) |
| { |
| struct visconti_pll *pll = to_visconti_pll(hw); |
| struct visconti_pll_rate_table rate_table; |
| |
| memset(&rate_table, 0, sizeof(rate_table)); |
| visconti_pll_get_params(pll, &rate_table); |
| |
| return visconti_get_pll_rate_from_data(pll, &rate_table); |
| } |
| |
| static int visconti_pll_set_params(struct visconti_pll *pll, |
| const struct visconti_pll_rate_table *rate_table) |
| { |
| writel(PLL_CREATE_FRACMODE(rate_table), pll->pll_base + PLL_FRACMODE_REG); |
| writel(PLL_CREATE_OSTDIV(rate_table), pll->pll_base + PLL_POSTDIV_REG); |
| writel(rate_table->intin, pll->pll_base + PLL_INTIN_REG); |
| writel(rate_table->fracin, pll->pll_base + PLL_FRACIN_REG); |
| writel(rate_table->refdiv, pll->pll_base + PLL_REFDIV_REG); |
| |
| return 0; |
| } |
| |
| static int visconti_pll_set_rate(struct clk_hw *hw, unsigned long rate, |
| unsigned long parent_rate) |
| { |
| struct visconti_pll *pll = to_visconti_pll(hw); |
| const struct visconti_pll_rate_table *rate_table; |
| |
| rate_table = visconti_get_pll_settings(pll, rate); |
| if (!rate_table) |
| return -EINVAL; |
| |
| return visconti_pll_set_params(pll, rate_table); |
| } |
| |
| static int visconti_pll_is_enabled(struct clk_hw *hw) |
| { |
| struct visconti_pll *pll = to_visconti_pll(hw); |
| u32 reg; |
| |
| reg = readl(pll->pll_base + PLL_CTRL_REG); |
| |
| return (reg & PLL_PLLEN); |
| } |
| |
| static int visconti_pll_enable(struct clk_hw *hw) |
| { |
| struct visconti_pll *pll = to_visconti_pll(hw); |
| const struct visconti_pll_rate_table *rate_table = pll->rate_table; |
| unsigned long flags; |
| u32 reg; |
| |
| if (visconti_pll_is_enabled(hw)) |
| return 0; |
| |
| spin_lock_irqsave(pll->lock, flags); |
| |
| writel(PLL_CONFIG_SEL, pll->pll_base + PLL_CONF_REG); |
| |
| reg = readl(pll->pll_base + PLL_CTRL_REG); |
| reg |= PLL_BYPASS; |
| writel(reg, pll->pll_base + PLL_CTRL_REG); |
| |
| visconti_pll_set_params(pll, &rate_table[0]); |
| |
| reg = readl(pll->pll_base + PLL_CTRL_REG); |
| reg &= ~PLL_PLLEN; |
| writel(reg, pll->pll_base + PLL_CTRL_REG); |
| |
| udelay(1); |
| |
| reg = readl(pll->pll_base + PLL_CTRL_REG); |
| reg |= PLL_PLLEN; |
| writel(reg, pll->pll_base + PLL_CTRL_REG); |
| |
| udelay(40); |
| |
| reg = readl(pll->pll_base + PLL_CTRL_REG); |
| reg &= ~PLL_BYPASS; |
| writel(reg, pll->pll_base + PLL_CTRL_REG); |
| |
| spin_unlock_irqrestore(pll->lock, flags); |
| |
| return 0; |
| } |
| |
| static void visconti_pll_disable(struct clk_hw *hw) |
| { |
| struct visconti_pll *pll = to_visconti_pll(hw); |
| unsigned long flags; |
| u32 reg; |
| |
| if (!visconti_pll_is_enabled(hw)) |
| return; |
| |
| spin_lock_irqsave(pll->lock, flags); |
| |
| writel(PLL_CONFIG_SEL, pll->pll_base + PLL_CONF_REG); |
| |
| reg = readl(pll->pll_base + PLL_CTRL_REG); |
| reg |= PLL_BYPASS; |
| writel(reg, pll->pll_base + PLL_CTRL_REG); |
| |
| reg = readl(pll->pll_base + PLL_CTRL_REG); |
| reg &= ~PLL_PLLEN; |
| writel(reg, pll->pll_base + PLL_CTRL_REG); |
| |
| spin_unlock_irqrestore(pll->lock, flags); |
| } |
| |
| static const struct clk_ops visconti_pll_ops = { |
| .enable = visconti_pll_enable, |
| .disable = visconti_pll_disable, |
| .is_enabled = visconti_pll_is_enabled, |
| .round_rate = visconti_pll_round_rate, |
| .recalc_rate = visconti_pll_recalc_rate, |
| .set_rate = visconti_pll_set_rate, |
| }; |
| |
| static struct clk_hw *visconti_register_pll(struct visconti_pll_provider *ctx, |
| const char *name, |
| const char *parent_name, |
| int offset, |
| const struct visconti_pll_rate_table *rate_table, |
| spinlock_t *lock) |
| { |
| struct clk_init_data init; |
| struct visconti_pll *pll; |
| struct clk_hw *pll_hw_clk; |
| size_t len; |
| int ret; |
| |
| pll = kzalloc(sizeof(*pll), GFP_KERNEL); |
| if (!pll) |
| return ERR_PTR(-ENOMEM); |
| |
| init.name = name; |
| init.flags = CLK_IGNORE_UNUSED; |
| init.parent_names = &parent_name; |
| init.num_parents = 1; |
| |
| for (len = 0; rate_table[len].rate != 0; ) |
| len++; |
| pll->rate_count = len; |
| pll->rate_table = kmemdup(rate_table, |
| pll->rate_count * sizeof(struct visconti_pll_rate_table), |
| GFP_KERNEL); |
| WARN(!pll->rate_table, "%s: could not allocate rate table for %s\n", __func__, name); |
| |
| init.ops = &visconti_pll_ops; |
| pll->hw.init = &init; |
| pll->pll_base = ctx->reg_base + offset; |
| pll->lock = lock; |
| pll->ctx = ctx; |
| |
| pll_hw_clk = &pll->hw; |
| ret = clk_hw_register(NULL, &pll->hw); |
| if (ret) { |
| pr_err("failed to register pll clock %s : %d\n", name, ret); |
| kfree(pll->rate_table); |
| kfree(pll); |
| pll_hw_clk = ERR_PTR(ret); |
| } |
| |
| return pll_hw_clk; |
| } |
| |
| static void visconti_pll_add_lookup(struct visconti_pll_provider *ctx, |
| struct clk_hw *hw_clk, |
| unsigned int id) |
| { |
| if (id) |
| ctx->clk_data.hws[id] = hw_clk; |
| } |
| |
| void __init visconti_register_plls(struct visconti_pll_provider *ctx, |
| const struct visconti_pll_info *list, |
| unsigned int nr_plls, |
| spinlock_t *lock) |
| { |
| int idx; |
| |
| for (idx = 0; idx < nr_plls; idx++, list++) { |
| struct clk_hw *clk; |
| |
| clk = visconti_register_pll(ctx, |
| list->name, |
| list->parent, |
| list->base_reg, |
| list->rate_table, |
| lock); |
| if (IS_ERR(clk)) { |
| pr_err("failed to register clock %s\n", list->name); |
| continue; |
| } |
| |
| visconti_pll_add_lookup(ctx, clk, list->id); |
| } |
| } |
| |
| struct visconti_pll_provider * __init visconti_init_pll(struct device_node *np, |
| void __iomem *base, |
| unsigned long nr_plls) |
| { |
| struct visconti_pll_provider *ctx; |
| int i; |
| |
| ctx = kzalloc(struct_size(ctx, clk_data.hws, nr_plls), GFP_KERNEL); |
| if (!ctx) |
| return ERR_PTR(-ENOMEM); |
| |
| ctx->node = np; |
| ctx->reg_base = base; |
| ctx->clk_data.num = nr_plls; |
| |
| for (i = 0; i < nr_plls; ++i) |
| ctx->clk_data.hws[i] = ERR_PTR(-ENOENT); |
| |
| return ctx; |
| } |