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/spinlock.h> 13 14 #include "ccu_frac.h" 15 16 bool ccu_frac_helper_is_enabled(struct ccu_common *common, 17 struct ccu_frac_internal *cf) 18 { 19 if (!(common->features & CCU_FEATURE_FRACTIONAL)) 20 return false; 21 22 return !(readl(common->base + common->reg) & cf->enable); 23 } 24 25 void ccu_frac_helper_enable(struct ccu_common *common, 26 struct ccu_frac_internal *cf) 27 { 28 unsigned long flags; 29 u32 reg; 30 31 if (!(common->features & CCU_FEATURE_FRACTIONAL)) 32 return; 33 34 spin_lock_irqsave(common->lock, flags); 35 reg = readl(common->base + common->reg); 36 writel(reg & ~cf->enable, common->base + common->reg); 37 spin_unlock_irqrestore(common->lock, flags); 38 } 39 40 void ccu_frac_helper_disable(struct ccu_common *common, 41 struct ccu_frac_internal *cf) 42 { 43 unsigned long flags; 44 u32 reg; 45 46 if (!(common->features & CCU_FEATURE_FRACTIONAL)) 47 return; 48 49 spin_lock_irqsave(common->lock, flags); 50 reg = readl(common->base + common->reg); 51 writel(reg | cf->enable, common->base + common->reg); 52 spin_unlock_irqrestore(common->lock, flags); 53 } 54 55 bool ccu_frac_helper_has_rate(struct ccu_common *common, 56 struct ccu_frac_internal *cf, 57 unsigned long rate) 58 { 59 if (!(common->features & CCU_FEATURE_FRACTIONAL)) 60 return false; 61 62 return (cf->rates[0] == rate) || (cf->rates[1] == rate); 63 } 64 65 unsigned long ccu_frac_helper_read_rate(struct ccu_common *common, 66 struct ccu_frac_internal *cf) 67 { 68 u32 reg; 69 70 pr_debug("%s: Read fractional\n", clk_hw_get_name(&common->hw)); 71 72 if (!(common->features & CCU_FEATURE_FRACTIONAL)) 73 return 0; 74 75 pr_debug("%s: clock is fractional (rates %lu and %lu)\n", 76 clk_hw_get_name(&common->hw), cf->rates[0], cf->rates[1]); 77 78 reg = readl(common->base + common->reg); 79 80 pr_debug("%s: clock reg is 0x%x (select is 0x%x)\n", 81 clk_hw_get_name(&common->hw), reg, cf->select); 82 83 return (reg & cf->select) ? cf->rates[1] : cf->rates[0]; 84 } 85 86 int ccu_frac_helper_set_rate(struct ccu_common *common, 87 struct ccu_frac_internal *cf, 88 unsigned long rate, u32 lock) 89 { 90 unsigned long flags; 91 u32 reg, sel; 92 93 if (!(common->features & CCU_FEATURE_FRACTIONAL)) 94 return -EINVAL; 95 96 if (cf->rates[0] == rate) 97 sel = 0; 98 else if (cf->rates[1] == rate) 99 sel = cf->select; 100 else 101 return -EINVAL; 102 103 spin_lock_irqsave(common->lock, flags); 104 reg = readl(common->base + common->reg); 105 reg &= ~cf->select; 106 writel(reg | sel, common->base + common->reg); 107 spin_unlock_irqrestore(common->lock, flags); 108 109 ccu_helper_wait_for_lock(common, lock); 110 111 return 0; 112 } 113