| /* |
| * Copyright (C) 2016 Maxime Ripard |
| * Maxime Ripard <maxime.ripard@free-electrons.com> |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License as |
| * published by the Free Software Foundation; either version 2 of |
| * the License, or (at your option) any later version. |
| */ |
| |
| #include <linux/clk-provider.h> |
| #include <linux/rational.h> |
| |
| #include "ccu_frac.h" |
| #include "ccu_gate.h" |
| #include "ccu_nm.h" |
| |
| static void ccu_nm_disable(struct clk_hw *hw) |
| { |
| struct ccu_nm *nm = hw_to_ccu_nm(hw); |
| |
| return ccu_gate_helper_disable(&nm->common, nm->enable); |
| } |
| |
| static int ccu_nm_enable(struct clk_hw *hw) |
| { |
| struct ccu_nm *nm = hw_to_ccu_nm(hw); |
| |
| return ccu_gate_helper_enable(&nm->common, nm->enable); |
| } |
| |
| static int ccu_nm_is_enabled(struct clk_hw *hw) |
| { |
| struct ccu_nm *nm = hw_to_ccu_nm(hw); |
| |
| return ccu_gate_helper_is_enabled(&nm->common, nm->enable); |
| } |
| |
| static unsigned long ccu_nm_recalc_rate(struct clk_hw *hw, |
| unsigned long parent_rate) |
| { |
| struct ccu_nm *nm = hw_to_ccu_nm(hw); |
| unsigned long n, m; |
| u32 reg; |
| |
| if (ccu_frac_helper_is_enabled(&nm->common, &nm->frac)) |
| return ccu_frac_helper_read_rate(&nm->common, &nm->frac); |
| |
| reg = readl(nm->common.base + nm->common.reg); |
| |
| n = reg >> nm->n.shift; |
| n &= (1 << nm->n.width) - 1; |
| |
| m = reg >> nm->m.shift; |
| m &= (1 << nm->m.width) - 1; |
| |
| return parent_rate * (n + 1) / (m + 1); |
| } |
| |
| static long ccu_nm_round_rate(struct clk_hw *hw, unsigned long rate, |
| unsigned long *parent_rate) |
| { |
| struct ccu_nm *nm = hw_to_ccu_nm(hw); |
| unsigned long n, m; |
| |
| rational_best_approximation(rate, *parent_rate, |
| 1 << nm->n.width, 1 << nm->m.width, |
| &n, &m); |
| |
| return *parent_rate * n / m; |
| } |
| |
| static int ccu_nm_set_rate(struct clk_hw *hw, unsigned long rate, |
| unsigned long parent_rate) |
| { |
| struct ccu_nm *nm = hw_to_ccu_nm(hw); |
| unsigned long flags; |
| unsigned long n, m; |
| u32 reg; |
| |
| if (ccu_frac_helper_has_rate(&nm->common, &nm->frac, rate)) |
| return ccu_frac_helper_set_rate(&nm->common, &nm->frac, rate); |
| else |
| ccu_frac_helper_disable(&nm->common, &nm->frac); |
| |
| rational_best_approximation(rate, parent_rate, |
| 1 << nm->n.width, 1 << nm->m.width, |
| &n, &m); |
| |
| spin_lock_irqsave(nm->common.lock, flags); |
| |
| reg = readl(nm->common.base + nm->common.reg); |
| reg &= ~GENMASK(nm->n.width + nm->n.shift - 1, nm->n.shift); |
| reg &= ~GENMASK(nm->m.width + nm->m.shift - 1, nm->m.shift); |
| |
| writel(reg | ((m - 1) << nm->m.shift) | ((n - 1) << nm->n.shift), |
| nm->common.base + nm->common.reg); |
| |
| spin_unlock_irqrestore(nm->common.lock, flags); |
| |
| ccu_helper_wait_for_lock(&nm->common, nm->lock); |
| |
| return 0; |
| } |
| |
| const struct clk_ops ccu_nm_ops = { |
| .disable = ccu_nm_disable, |
| .enable = ccu_nm_enable, |
| .is_enabled = ccu_nm_is_enabled, |
| |
| .recalc_rate = ccu_nm_recalc_rate, |
| .round_rate = ccu_nm_round_rate, |
| .set_rate = ccu_nm_set_rate, |
| }; |