1 /* 2 * OMAP clockdomain support 3 * 4 * Copyright (C) 2013 Texas Instruments, Inc. 5 * 6 * Tero Kristo <t-kristo@ti.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 * 12 * This program is distributed "as is" WITHOUT ANY WARRANTY of any 13 * kind, whether express or implied; without even the implied warranty 14 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 */ 17 18 #include <linux/clk.h> 19 #include <linux/clk-provider.h> 20 #include <linux/slab.h> 21 #include <linux/of.h> 22 #include <linux/of_address.h> 23 #include <linux/clk/ti.h> 24 25 #include "clock.h" 26 27 #undef pr_fmt 28 #define pr_fmt(fmt) "%s: " fmt, __func__ 29 30 /** 31 * omap2_clkops_enable_clkdm - increment usecount on clkdm of @hw 32 * @hw: struct clk_hw * of the clock being enabled 33 * 34 * Increment the usecount of the clockdomain of the clock pointed to 35 * by @hw; if the usecount is 1, the clockdomain will be "enabled." 36 * Only needed for clocks that don't use omap2_dflt_clk_enable() as 37 * their enable function pointer. Passes along the return value of 38 * clkdm_clk_enable(), -EINVAL if @hw is not associated with a 39 * clockdomain, or 0 if clock framework-based clockdomain control is 40 * not implemented. 41 */ 42 int omap2_clkops_enable_clkdm(struct clk_hw *hw) 43 { 44 struct clk_hw_omap *clk; 45 int ret = 0; 46 47 clk = to_clk_hw_omap(hw); 48 49 if (unlikely(!clk->clkdm)) { 50 pr_err("%s: %s: no clkdm set ?!\n", __func__, 51 clk_hw_get_name(hw)); 52 return -EINVAL; 53 } 54 55 if (unlikely(clk->enable_reg)) 56 pr_err("%s: %s: should use dflt_clk_enable ?!\n", __func__, 57 clk_hw_get_name(hw)); 58 59 if (ti_clk_get_features()->flags & TI_CLK_DISABLE_CLKDM_CONTROL) { 60 pr_err("%s: %s: clkfw-based clockdomain control disabled ?!\n", 61 __func__, clk_hw_get_name(hw)); 62 return 0; 63 } 64 65 ret = ti_clk_ll_ops->clkdm_clk_enable(clk->clkdm, hw->clk); 66 WARN(ret, "%s: could not enable %s's clockdomain %s: %d\n", 67 __func__, clk_hw_get_name(hw), clk->clkdm_name, ret); 68 69 return ret; 70 } 71 72 /** 73 * omap2_clkops_disable_clkdm - decrement usecount on clkdm of @hw 74 * @hw: struct clk_hw * of the clock being disabled 75 * 76 * Decrement the usecount of the clockdomain of the clock pointed to 77 * by @hw; if the usecount is 0, the clockdomain will be "disabled." 78 * Only needed for clocks that don't use omap2_dflt_clk_disable() as their 79 * disable function pointer. No return value. 80 */ 81 void omap2_clkops_disable_clkdm(struct clk_hw *hw) 82 { 83 struct clk_hw_omap *clk; 84 85 clk = to_clk_hw_omap(hw); 86 87 if (unlikely(!clk->clkdm)) { 88 pr_err("%s: %s: no clkdm set ?!\n", __func__, 89 clk_hw_get_name(hw)); 90 return; 91 } 92 93 if (unlikely(clk->enable_reg)) 94 pr_err("%s: %s: should use dflt_clk_disable ?!\n", __func__, 95 clk_hw_get_name(hw)); 96 97 if (ti_clk_get_features()->flags & TI_CLK_DISABLE_CLKDM_CONTROL) { 98 pr_err("%s: %s: clkfw-based clockdomain control disabled ?!\n", 99 __func__, clk_hw_get_name(hw)); 100 return; 101 } 102 103 ti_clk_ll_ops->clkdm_clk_disable(clk->clkdm, hw->clk); 104 } 105 106 static void __init of_ti_clockdomain_setup(struct device_node *node) 107 { 108 struct clk *clk; 109 struct clk_hw *clk_hw; 110 const char *clkdm_name = node->name; 111 int i; 112 int num_clks; 113 114 num_clks = of_clk_get_parent_count(node); 115 116 for (i = 0; i < num_clks; i++) { 117 clk = of_clk_get(node, i); 118 if (IS_ERR(clk)) { 119 pr_err("%s: Failed get %s' clock nr %d (%ld)\n", 120 __func__, node->full_name, i, PTR_ERR(clk)); 121 continue; 122 } 123 clk_hw = __clk_get_hw(clk); 124 if (clk_hw_get_flags(clk_hw) & CLK_IS_BASIC) { 125 pr_warn("can't setup clkdm for basic clk %s\n", 126 __clk_get_name(clk)); 127 continue; 128 } 129 to_clk_hw_omap(clk_hw)->clkdm_name = clkdm_name; 130 omap2_init_clk_clkdm(clk_hw); 131 } 132 } 133 134 static const struct of_device_id ti_clkdm_match_table[] __initconst = { 135 { .compatible = "ti,clockdomain" }, 136 { } 137 }; 138 139 /** 140 * ti_dt_clockdomains_setup - setup device tree clockdomains 141 * 142 * Initializes clockdomain nodes for a SoC. This parses through all the 143 * nodes with compatible = "ti,clockdomain", and add the clockdomain 144 * info for all the clocks listed under these. This function shall be 145 * called after rest of the DT clock init has completed and all 146 * clock nodes have been registered. 147 */ 148 void __init ti_dt_clockdomains_setup(void) 149 { 150 struct device_node *np; 151 for_each_matching_node(np, ti_clkdm_match_table) { 152 of_ti_clockdomain_setup(np); 153 } 154 } 155