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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 | /* * mmp gate clock operation source file * * Copyright (C) 2014 Marvell * Chao Xie <chao.xie@marvell.com> * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. */ #include <linux/clk-provider.h> #include <linux/slab.h> #include <linux/io.h> #include <linux/err.h> #include <linux/delay.h> #include "clk.h" /* * Some clocks will have mutiple bits to enable the clocks, and * the bits to disable the clock is not same as enabling bits. */ #define to_clk_mmp_gate(hw) container_of(hw, struct mmp_clk_gate, hw) static int mmp_clk_gate_enable(struct clk_hw *hw) { struct mmp_clk_gate *gate = to_clk_mmp_gate(hw); unsigned long flags = 0; unsigned long rate; u32 tmp; if (gate->lock) spin_lock_irqsave(gate->lock, flags); tmp = readl(gate->reg); tmp &= ~gate->mask; tmp |= gate->val_enable; writel(tmp, gate->reg); if (gate->lock) spin_unlock_irqrestore(gate->lock, flags); if (gate->flags & MMP_CLK_GATE_NEED_DELAY) { rate = clk_hw_get_rate(hw); /* Need delay 2 cycles. */ udelay(2000000/rate); } return 0; } static void mmp_clk_gate_disable(struct clk_hw *hw) { struct mmp_clk_gate *gate = to_clk_mmp_gate(hw); unsigned long flags = 0; u32 tmp; if (gate->lock) spin_lock_irqsave(gate->lock, flags); tmp = readl(gate->reg); tmp &= ~gate->mask; tmp |= gate->val_disable; writel(tmp, gate->reg); if (gate->lock) spin_unlock_irqrestore(gate->lock, flags); } static int mmp_clk_gate_is_enabled(struct clk_hw *hw) { struct mmp_clk_gate *gate = to_clk_mmp_gate(hw); unsigned long flags = 0; u32 tmp; if (gate->lock) spin_lock_irqsave(gate->lock, flags); tmp = readl(gate->reg); if (gate->lock) spin_unlock_irqrestore(gate->lock, flags); return (tmp & gate->mask) == gate->val_enable; } const struct clk_ops mmp_clk_gate_ops = { .enable = mmp_clk_gate_enable, .disable = mmp_clk_gate_disable, .is_enabled = mmp_clk_gate_is_enabled, }; struct clk *mmp_clk_register_gate(struct device *dev, const char *name, const char *parent_name, unsigned long flags, void __iomem *reg, u32 mask, u32 val_enable, u32 val_disable, unsigned int gate_flags, spinlock_t *lock) { struct mmp_clk_gate *gate; struct clk *clk; struct clk_init_data init; /* allocate the gate */ gate = kzalloc(sizeof(*gate), GFP_KERNEL); if (!gate) return ERR_PTR(-ENOMEM); init.name = name; init.ops = &mmp_clk_gate_ops; init.flags = flags | CLK_IS_BASIC; init.parent_names = (parent_name ? &parent_name : NULL); init.num_parents = (parent_name ? 1 : 0); /* struct clk_gate assignments */ gate->reg = reg; gate->mask = mask; gate->val_enable = val_enable; gate->val_disable = val_disable; gate->flags = gate_flags; gate->lock = lock; gate->hw.init = &init; clk = clk_register(dev, &gate->hw); if (IS_ERR(clk)) kfree(gate); return clk; } |