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.h> 19 #include <linux/clk-provider.h> 20 #include <linux/of.h> 21 #include <linux/of_address.h> 22 #include <linux/delay.h> 23 #include <linux/export.h> 24 #include <linux/clk/tegra.h> 25 26 #include "clk.h" 27 #include "clk-id.h" 28 29 #define OSC_CTRL 0x50 30 #define OSC_CTRL_OSC_FREQ_SHIFT 28 31 #define OSC_CTRL_PLL_REF_DIV_SHIFT 26 32 33 int __init tegra_osc_clk_init(void __iomem *clk_base, 34 struct tegra_clk *tegra_clks, 35 unsigned long *input_freqs, int num, 36 unsigned long *osc_freq, 37 unsigned long *pll_ref_freq) 38 { 39 struct clk *clk; 40 struct clk **dt_clk; 41 u32 val, pll_ref_div; 42 unsigned osc_idx; 43 44 val = readl_relaxed(clk_base + OSC_CTRL); 45 osc_idx = val >> OSC_CTRL_OSC_FREQ_SHIFT; 46 47 if (osc_idx < num) 48 *osc_freq = input_freqs[osc_idx]; 49 else 50 *osc_freq = 0; 51 52 if (!*osc_freq) { 53 WARN_ON(1); 54 return -EINVAL; 55 } 56 57 dt_clk = tegra_lookup_dt_id(tegra_clk_clk_m, tegra_clks); 58 if (!dt_clk) 59 return 0; 60 61 clk = clk_register_fixed_rate(NULL, "clk_m", NULL, CLK_IS_ROOT, 62 *osc_freq); 63 *dt_clk = clk; 64 65 /* pll_ref */ 66 val = (val >> OSC_CTRL_PLL_REF_DIV_SHIFT) & 3; 67 pll_ref_div = 1 << val; 68 dt_clk = tegra_lookup_dt_id(tegra_clk_pll_ref, tegra_clks); 69 if (!dt_clk) 70 return 0; 71 72 clk = clk_register_fixed_factor(NULL, "pll_ref", "clk_m", 73 0, 1, pll_ref_div); 74 *dt_clk = clk; 75 76 if (pll_ref_freq) 77 *pll_ref_freq = *osc_freq / pll_ref_div; 78 79 return 0; 80 } 81 82 void __init tegra_fixed_clk_init(struct tegra_clk *tegra_clks) 83 { 84 struct clk *clk; 85 struct clk **dt_clk; 86 87 /* clk_32k */ 88 dt_clk = tegra_lookup_dt_id(tegra_clk_clk_32k, tegra_clks); 89 if (dt_clk) { 90 clk = clk_register_fixed_rate(NULL, "clk_32k", NULL, 91 CLK_IS_ROOT, 32768); 92 *dt_clk = clk; 93 } 94 95 /* clk_m_div2 */ 96 dt_clk = tegra_lookup_dt_id(tegra_clk_clk_m_div2, tegra_clks); 97 if (dt_clk) { 98 clk = clk_register_fixed_factor(NULL, "clk_m_div2", "clk_m", 99 CLK_SET_RATE_PARENT, 1, 2); 100 *dt_clk = clk; 101 } 102 103 /* clk_m_div4 */ 104 dt_clk = tegra_lookup_dt_id(tegra_clk_clk_m_div4, tegra_clks); 105 if (dt_clk) { 106 clk = clk_register_fixed_factor(NULL, "clk_m_div4", "clk_m", 107 CLK_SET_RATE_PARENT, 1, 4); 108 *dt_clk = clk; 109 } 110 } 111 112