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torvalds
GitHub Repository: torvalds/linux
 Path: blob/master/arch/mips/ralink/clk.c
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// SPDX-License-Identifier: GPL-2.0-only

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/*

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 *

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 *  Copyright (C) 2011 Gabor Juhos <[email protected]>

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 *  Copyright (C) 2013 John Crispin <[email protected]>

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 */

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#include <linux/kernel.h>

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#include <linux/init.h>

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#include <linux/export.h>

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#include <linux/clkdev.h>

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#include <linux/clk.h>

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#include <linux/clk-provider.h>

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#include <asm/mach-ralink/ralink_regs.h>

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#include <asm/time.h>

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#include "common.h"

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static const char *clk_cpu(int *idx)

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{

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	switch (ralink_soc) {

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	case RT2880_SOC:

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		*idx = 0;

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		return "ralink,rt2880-sysc";

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	case RT3883_SOC:

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		*idx = 0;

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		return "ralink,rt3883-sysc";

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	case RT305X_SOC_RT3050:

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		*idx = 0;

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		return "ralink,rt3050-sysc";

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	case RT305X_SOC_RT3052:

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		*idx = 0;

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		return "ralink,rt3052-sysc";

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	case RT305X_SOC_RT3350:

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		*idx = 1;

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		return "ralink,rt3350-sysc";

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	case RT305X_SOC_RT3352:

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		*idx = 1;

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		return "ralink,rt3352-sysc";

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	case RT305X_SOC_RT5350:

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		*idx = 1;

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		return "ralink,rt5350-sysc";

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	case MT762X_SOC_MT7620A:

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		*idx = 2;

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		return "ralink,mt7620-sysc";

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	case MT762X_SOC_MT7620N:

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		*idx = 2;

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		return "ralink,mt7620-sysc";

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	case MT762X_SOC_MT7628AN:

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		*idx = 1;

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		return "ralink,mt7628-sysc";

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	case MT762X_SOC_MT7688:

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		*idx = 1;

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		return "ralink,mt7688-sysc";

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	default:

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		*idx = -1;

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		return "invalid";

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	}

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}

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void __init plat_time_init(void)

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{

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	struct of_phandle_args clkspec;

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	const char *compatible;

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	struct clk *clk;

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	int cpu_clk_idx;

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	ralink_of_remap();

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	compatible = clk_cpu(&cpu_clk_idx);

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	if (cpu_clk_idx == -1)

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		panic("unable to get CPU clock index");

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	of_clk_init(NULL);

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	clkspec.np = of_find_compatible_node(NULL, NULL, compatible);

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	clkspec.args_count = 1;

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	clkspec.args[0] = cpu_clk_idx;

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	clk = of_clk_get_from_provider(&clkspec);

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	if (IS_ERR(clk))

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		panic("unable to get CPU clock, err=%ld", PTR_ERR(clk));

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	pr_info("CPU Clock: %ldMHz\n", clk_get_rate(clk) / 1000000);

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	mips_hpt_frequency = clk_get_rate(clk) / 2;

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	clk_put(clk);

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	timer_probe();

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}

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