123 lines
4.1 KiB
C
123 lines
4.1 KiB
C
/*
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* Copyright (c) 2012-2016 Zhang, Keguang <keguang.zhang@gmail.com>
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the
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* Free Software Foundation; either version 2 of the License, or (at your
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* option) any later version.
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*/
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#include <linux/clkdev.h>
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#include <linux/clk-provider.h>
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#include <linux/io.h>
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#include <linux/err.h>
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#include <loongson1.h>
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#include "clk.h"
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#define OSC (33 * 1000000)
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#define DIV_APB 2
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static DEFINE_SPINLOCK(_lock);
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static unsigned long ls1x_pll_recalc_rate(struct clk_hw *hw,
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unsigned long parent_rate)
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{
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u32 pll, rate;
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pll = __raw_readl(LS1X_CLK_PLL_FREQ);
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rate = 12 + (pll & GENMASK(5, 0));
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rate *= OSC;
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rate >>= 1;
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return rate;
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}
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static const struct clk_ops ls1x_pll_clk_ops = {
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.recalc_rate = ls1x_pll_recalc_rate,
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};
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static const char *const cpu_parents[] = { "cpu_clk_div", "osc_clk", };
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static const char *const ahb_parents[] = { "ahb_clk_div", "osc_clk", };
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static const char *const dc_parents[] = { "dc_clk_div", "osc_clk", };
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void __init ls1x_clk_init(void)
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{
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struct clk_hw *hw;
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hw = clk_hw_register_fixed_rate(NULL, "osc_clk", NULL, 0, OSC);
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clk_hw_register_clkdev(hw, "osc_clk", NULL);
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/* clock derived from 33 MHz OSC clk */
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hw = clk_hw_register_pll(NULL, "pll_clk", "osc_clk",
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&ls1x_pll_clk_ops, 0);
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clk_hw_register_clkdev(hw, "pll_clk", NULL);
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/* clock derived from PLL clk */
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/* _____
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* _______________________| |
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* OSC ___/ | MUX |___ CPU CLK
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* \___ PLL ___ CPU DIV ___| |
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* |_____|
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*/
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hw = clk_hw_register_divider(NULL, "cpu_clk_div", "pll_clk",
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CLK_GET_RATE_NOCACHE, LS1X_CLK_PLL_DIV,
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DIV_CPU_SHIFT, DIV_CPU_WIDTH,
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CLK_DIVIDER_ONE_BASED |
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CLK_DIVIDER_ROUND_CLOSEST, &_lock);
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clk_hw_register_clkdev(hw, "cpu_clk_div", NULL);
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hw = clk_hw_register_mux(NULL, "cpu_clk", cpu_parents,
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ARRAY_SIZE(cpu_parents),
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CLK_SET_RATE_NO_REPARENT, LS1X_CLK_PLL_DIV,
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BYPASS_CPU_SHIFT, BYPASS_CPU_WIDTH, 0, &_lock);
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clk_hw_register_clkdev(hw, "cpu_clk", NULL);
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/* _____
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* _______________________| |
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* OSC ___/ | MUX |___ DC CLK
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* \___ PLL ___ DC DIV ___| |
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* |_____|
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*/
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hw = clk_hw_register_divider(NULL, "dc_clk_div", "pll_clk",
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0, LS1X_CLK_PLL_DIV, DIV_DC_SHIFT,
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DIV_DC_WIDTH, CLK_DIVIDER_ONE_BASED, &_lock);
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clk_hw_register_clkdev(hw, "dc_clk_div", NULL);
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hw = clk_hw_register_mux(NULL, "dc_clk", dc_parents,
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ARRAY_SIZE(dc_parents),
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CLK_SET_RATE_NO_REPARENT, LS1X_CLK_PLL_DIV,
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BYPASS_DC_SHIFT, BYPASS_DC_WIDTH, 0, &_lock);
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clk_hw_register_clkdev(hw, "dc_clk", NULL);
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/* _____
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* _______________________| |
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* OSC ___/ | MUX |___ DDR CLK
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* \___ PLL ___ DDR DIV ___| |
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* |_____|
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*/
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hw = clk_hw_register_divider(NULL, "ahb_clk_div", "pll_clk",
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0, LS1X_CLK_PLL_DIV, DIV_DDR_SHIFT,
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DIV_DDR_WIDTH, CLK_DIVIDER_ONE_BASED,
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&_lock);
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clk_hw_register_clkdev(hw, "ahb_clk_div", NULL);
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hw = clk_hw_register_mux(NULL, "ahb_clk", ahb_parents,
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ARRAY_SIZE(ahb_parents),
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CLK_SET_RATE_NO_REPARENT, LS1X_CLK_PLL_DIV,
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BYPASS_DDR_SHIFT, BYPASS_DDR_WIDTH, 0, &_lock);
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clk_hw_register_clkdev(hw, "ahb_clk", NULL);
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clk_hw_register_clkdev(hw, "ls1x-dma", NULL);
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clk_hw_register_clkdev(hw, "stmmaceth", NULL);
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/* clock derived from AHB clk */
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/* APB clk is always half of the AHB clk */
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hw = clk_hw_register_fixed_factor(NULL, "apb_clk", "ahb_clk", 0, 1,
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DIV_APB);
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clk_hw_register_clkdev(hw, "apb_clk", NULL);
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clk_hw_register_clkdev(hw, "ls1x-ac97", NULL);
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clk_hw_register_clkdev(hw, "ls1x-i2c", NULL);
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clk_hw_register_clkdev(hw, "ls1x-nand", NULL);
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clk_hw_register_clkdev(hw, "ls1x-pwmtimer", NULL);
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clk_hw_register_clkdev(hw, "ls1x-spi", NULL);
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clk_hw_register_clkdev(hw, "ls1x-wdt", NULL);
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clk_hw_register_clkdev(hw, "serial8250", NULL);
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}
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