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108 lines
2.2 KiB
108 lines
2.2 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* Copyright (c) 2014 Lucas Stach <[email protected]>, Pengutronix |
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*/ |
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#include <linux/clk.h> |
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#include <linux/clk-provider.h> |
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#include <linux/export.h> |
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#include <linux/slab.h> |
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#include "clk.h" |
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struct clk_cpu { |
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struct clk_hw hw; |
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struct clk *div; |
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struct clk *mux; |
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struct clk *pll; |
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struct clk *step; |
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}; |
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static inline struct clk_cpu *to_clk_cpu(struct clk_hw *hw) |
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{ |
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return container_of(hw, struct clk_cpu, hw); |
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} |
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static unsigned long clk_cpu_recalc_rate(struct clk_hw *hw, |
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unsigned long parent_rate) |
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{ |
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struct clk_cpu *cpu = to_clk_cpu(hw); |
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return clk_get_rate(cpu->div); |
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} |
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static long clk_cpu_round_rate(struct clk_hw *hw, unsigned long rate, |
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unsigned long *prate) |
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{ |
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struct clk_cpu *cpu = to_clk_cpu(hw); |
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return clk_round_rate(cpu->pll, rate); |
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} |
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static int clk_cpu_set_rate(struct clk_hw *hw, unsigned long rate, |
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unsigned long parent_rate) |
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{ |
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struct clk_cpu *cpu = to_clk_cpu(hw); |
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int ret; |
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/* switch to PLL bypass clock */ |
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ret = clk_set_parent(cpu->mux, cpu->step); |
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if (ret) |
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return ret; |
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/* reprogram PLL */ |
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ret = clk_set_rate(cpu->pll, rate); |
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if (ret) { |
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clk_set_parent(cpu->mux, cpu->pll); |
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return ret; |
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} |
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/* switch back to PLL clock */ |
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clk_set_parent(cpu->mux, cpu->pll); |
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/* Ensure the divider is what we expect */ |
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clk_set_rate(cpu->div, rate); |
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return 0; |
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} |
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static const struct clk_ops clk_cpu_ops = { |
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.recalc_rate = clk_cpu_recalc_rate, |
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.round_rate = clk_cpu_round_rate, |
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.set_rate = clk_cpu_set_rate, |
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}; |
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struct clk_hw *imx_clk_hw_cpu(const char *name, const char *parent_name, |
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struct clk *div, struct clk *mux, struct clk *pll, |
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struct clk *step) |
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{ |
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struct clk_cpu *cpu; |
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struct clk_hw *hw; |
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struct clk_init_data init; |
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int ret; |
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cpu = kzalloc(sizeof(*cpu), GFP_KERNEL); |
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if (!cpu) |
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return ERR_PTR(-ENOMEM); |
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cpu->div = div; |
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cpu->mux = mux; |
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cpu->pll = pll; |
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cpu->step = step; |
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init.name = name; |
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init.ops = &clk_cpu_ops; |
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init.flags = CLK_IS_CRITICAL; |
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init.parent_names = &parent_name; |
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init.num_parents = 1; |
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cpu->hw.init = &init; |
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hw = &cpu->hw; |
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ret = clk_hw_register(NULL, hw); |
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if (ret) { |
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kfree(cpu); |
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return ERR_PTR(ret); |
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} |
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return hw; |
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} |
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EXPORT_SYMBOL_GPL(imx_clk_hw_cpu);
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