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112 lines
2.5 KiB
112 lines
2.5 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
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/* |
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* clk-h32mx.c |
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* |
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* Copyright (C) 2014 Atmel |
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* |
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* Alexandre Belloni <[email protected]> |
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*/ |
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#include <linux/clk-provider.h> |
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#include <linux/clkdev.h> |
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#include <linux/clk/at91_pmc.h> |
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#include <linux/of.h> |
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#include <linux/regmap.h> |
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#include <linux/mfd/syscon.h> |
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#include "pmc.h" |
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#define H32MX_MAX_FREQ 90000000 |
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struct clk_sama5d4_h32mx { |
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struct clk_hw hw; |
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struct regmap *regmap; |
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}; |
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#define to_clk_sama5d4_h32mx(hw) container_of(hw, struct clk_sama5d4_h32mx, hw) |
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static unsigned long clk_sama5d4_h32mx_recalc_rate(struct clk_hw *hw, |
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unsigned long parent_rate) |
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{ |
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struct clk_sama5d4_h32mx *h32mxclk = to_clk_sama5d4_h32mx(hw); |
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unsigned int mckr; |
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regmap_read(h32mxclk->regmap, AT91_PMC_MCKR, &mckr); |
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if (mckr & AT91_PMC_H32MXDIV) |
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return parent_rate / 2; |
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if (parent_rate > H32MX_MAX_FREQ) |
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pr_warn("H32MX clock is too fast\n"); |
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return parent_rate; |
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} |
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static long clk_sama5d4_h32mx_round_rate(struct clk_hw *hw, unsigned long rate, |
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unsigned long *parent_rate) |
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{ |
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unsigned long div; |
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if (rate > *parent_rate) |
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return *parent_rate; |
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div = *parent_rate / 2; |
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if (rate < div) |
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return div; |
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if (rate - div < *parent_rate - rate) |
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return div; |
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return *parent_rate; |
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} |
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static int clk_sama5d4_h32mx_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_sama5d4_h32mx *h32mxclk = to_clk_sama5d4_h32mx(hw); |
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u32 mckr = 0; |
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if (parent_rate != rate && (parent_rate / 2) != rate) |
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return -EINVAL; |
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if ((parent_rate / 2) == rate) |
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mckr = AT91_PMC_H32MXDIV; |
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regmap_update_bits(h32mxclk->regmap, AT91_PMC_MCKR, |
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AT91_PMC_H32MXDIV, mckr); |
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return 0; |
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} |
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static const struct clk_ops h32mx_ops = { |
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.recalc_rate = clk_sama5d4_h32mx_recalc_rate, |
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.round_rate = clk_sama5d4_h32mx_round_rate, |
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.set_rate = clk_sama5d4_h32mx_set_rate, |
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}; |
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struct clk_hw * __init |
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at91_clk_register_h32mx(struct regmap *regmap, const char *name, |
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const char *parent_name) |
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{ |
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struct clk_sama5d4_h32mx *h32mxclk; |
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struct clk_init_data init; |
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int ret; |
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h32mxclk = kzalloc(sizeof(*h32mxclk), GFP_KERNEL); |
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if (!h32mxclk) |
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return ERR_PTR(-ENOMEM); |
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init.name = name; |
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init.ops = &h32mx_ops; |
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init.parent_names = parent_name ? &parent_name : NULL; |
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init.num_parents = parent_name ? 1 : 0; |
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init.flags = CLK_SET_RATE_GATE; |
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h32mxclk->hw.init = &init; |
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h32mxclk->regmap = regmap; |
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ret = clk_hw_register(NULL, &h32mxclk->hw); |
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if (ret) { |
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kfree(h32mxclk); |
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return ERR_PTR(ret); |
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} |
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return &h32mxclk->hw; |
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}
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