1 /* 2 * Copyright (C) 2016 Maxime Ripard 3 * Maxime Ripard <maxime.ripard@free-electrons.com> 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU General Public License as 7 * published by the Free Software Foundation; either version 2 of 8 * the License, or (at your option) any later version. 9 */ 10 11 #include <linux/clk-provider.h> 12 #include <linux/io.h> 13 14 #include "ccu_gate.h" 15 16 void ccu_gate_helper_disable(struct ccu_common *common, u32 gate) 17 { 18 unsigned long flags; 19 u32 reg; 20 21 if (!gate) 22 return; 23 24 spin_lock_irqsave(common->lock, flags); 25 26 reg = readl(common->base + common->reg); 27 writel(reg & ~gate, common->base + common->reg); 28 29 spin_unlock_irqrestore(common->lock, flags); 30 } 31 32 static void ccu_gate_disable(struct clk_hw *hw) 33 { 34 struct ccu_gate *cg = hw_to_ccu_gate(hw); 35 36 return ccu_gate_helper_disable(&cg->common, cg->enable); 37 } 38 39 int ccu_gate_helper_enable(struct ccu_common *common, u32 gate) 40 { 41 unsigned long flags; 42 u32 reg; 43 44 if (!gate) 45 return 0; 46 47 spin_lock_irqsave(common->lock, flags); 48 49 reg = readl(common->base + common->reg); 50 writel(reg | gate, common->base + common->reg); 51 52 spin_unlock_irqrestore(common->lock, flags); 53 54 return 0; 55 } 56 57 static int ccu_gate_enable(struct clk_hw *hw) 58 { 59 struct ccu_gate *cg = hw_to_ccu_gate(hw); 60 61 return ccu_gate_helper_enable(&cg->common, cg->enable); 62 } 63 64 int ccu_gate_helper_is_enabled(struct ccu_common *common, u32 gate) 65 { 66 if (!gate) 67 return 1; 68 69 return readl(common->base + common->reg) & gate; 70 } 71 72 static int ccu_gate_is_enabled(struct clk_hw *hw) 73 { 74 struct ccu_gate *cg = hw_to_ccu_gate(hw); 75 76 return ccu_gate_helper_is_enabled(&cg->common, cg->enable); 77 } 78 79 static unsigned long ccu_gate_recalc_rate(struct clk_hw *hw, 80 unsigned long parent_rate) 81 { 82 struct ccu_gate *cg = hw_to_ccu_gate(hw); 83 unsigned long rate = parent_rate; 84 85 if (cg->common.features & CCU_FEATURE_ALL_PREDIV) 86 rate /= cg->common.prediv; 87 88 return rate; 89 } 90 91 static long ccu_gate_round_rate(struct clk_hw *hw, unsigned long rate, 92 unsigned long *prate) 93 { 94 struct ccu_gate *cg = hw_to_ccu_gate(hw); 95 int div = 1; 96 97 if (cg->common.features & CCU_FEATURE_ALL_PREDIV) 98 div = cg->common.prediv; 99 100 if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) { 101 unsigned long best_parent = rate; 102 103 if (cg->common.features & CCU_FEATURE_ALL_PREDIV) 104 best_parent *= div; 105 *prate = clk_hw_round_rate(clk_hw_get_parent(hw), best_parent); 106 } 107 108 return *prate / div; 109 } 110 111 static int ccu_gate_set_rate(struct clk_hw *hw, unsigned long rate, 112 unsigned long parent_rate) 113 { 114 /* 115 * We must report success but we can do so unconditionally because 116 * clk_factor_round_rate returns values that ensure this call is a 117 * nop. 118 */ 119 120 return 0; 121 } 122 123 const struct clk_ops ccu_gate_ops = { 124 .disable = ccu_gate_disable, 125 .enable = ccu_gate_enable, 126 .is_enabled = ccu_gate_is_enabled, 127 .round_rate = ccu_gate_round_rate, 128 .set_rate = ccu_gate_set_rate, 129 .recalc_rate = ccu_gate_recalc_rate, 130 }; 131