1 /* 2 * Copyright (c) 2012, 2013, NVIDIA CORPORATION. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or modify it 5 * under the terms and conditions of the GNU General Public License, 6 * version 2, as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 11 * more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program. If not, see <http://www.gnu.org/licenses/>. 15 */ 16 17 #include <linux/io.h> 18 #include <linux/clk-provider.h> 19 #include <linux/of.h> 20 #include <linux/of_address.h> 21 #include <linux/delay.h> 22 #include <linux/export.h> 23 #include <linux/clk/tegra.h> 24 25 #include "clk.h" 26 #include "clk-id.h" 27 28 #define OSC_CTRL 0x50 29 #define OSC_CTRL_OSC_FREQ_SHIFT 28 30 #define OSC_CTRL_PLL_REF_DIV_SHIFT 26 31 32 int __init tegra_osc_clk_init(void __iomem *clk_base, struct tegra_clk *clks, 33 unsigned long *input_freqs, unsigned int num, 34 unsigned int clk_m_div, unsigned long *osc_freq, 35 unsigned long *pll_ref_freq) 36 { 37 struct clk *clk, *osc; 38 struct clk **dt_clk; 39 u32 val, pll_ref_div; 40 unsigned osc_idx; 41 42 val = readl_relaxed(clk_base + OSC_CTRL); 43 osc_idx = val >> OSC_CTRL_OSC_FREQ_SHIFT; 44 45 if (osc_idx < num) 46 *osc_freq = input_freqs[osc_idx]; 47 else 48 *osc_freq = 0; 49 50 if (!*osc_freq) { 51 WARN_ON(1); 52 return -EINVAL; 53 } 54 55 osc = clk_register_fixed_rate(NULL, "osc", NULL, CLK_IS_ROOT, 56 *osc_freq); 57 58 dt_clk = tegra_lookup_dt_id(tegra_clk_clk_m, clks); 59 if (!dt_clk) 60 return 0; 61 62 clk = clk_register_fixed_factor(NULL, "clk_m", "osc", 63 0, 1, clk_m_div); 64 *dt_clk = clk; 65 66 /* pll_ref */ 67 val = (val >> OSC_CTRL_PLL_REF_DIV_SHIFT) & 3; 68 pll_ref_div = 1 << val; 69 dt_clk = tegra_lookup_dt_id(tegra_clk_pll_ref, clks); 70 if (!dt_clk) 71 return 0; 72 73 clk = clk_register_fixed_factor(NULL, "pll_ref", "osc", 74 0, 1, pll_ref_div); 75 *dt_clk = clk; 76 77 if (pll_ref_freq) 78 *pll_ref_freq = *osc_freq / pll_ref_div; 79 80 return 0; 81 } 82 83 void __init tegra_fixed_clk_init(struct tegra_clk *tegra_clks) 84 { 85 struct clk *clk; 86 struct clk **dt_clk; 87 88 /* clk_32k */ 89 dt_clk = tegra_lookup_dt_id(tegra_clk_clk_32k, tegra_clks); 90 if (dt_clk) { 91 clk = clk_register_fixed_rate(NULL, "clk_32k", NULL, 92 CLK_IS_ROOT, 32768); 93 *dt_clk = clk; 94 } 95 96 /* clk_m_div2 */ 97 dt_clk = tegra_lookup_dt_id(tegra_clk_clk_m_div2, tegra_clks); 98 if (dt_clk) { 99 clk = clk_register_fixed_factor(NULL, "clk_m_div2", "clk_m", 100 CLK_SET_RATE_PARENT, 1, 2); 101 *dt_clk = clk; 102 } 103 104 /* clk_m_div4 */ 105 dt_clk = tegra_lookup_dt_id(tegra_clk_clk_m_div4, tegra_clks); 106 if (dt_clk) { 107 clk = clk_register_fixed_factor(NULL, "clk_m_div4", "clk_m", 108 CLK_SET_RATE_PARENT, 1, 4); 109 *dt_clk = clk; 110 } 111 } 112 113