linux-imx

/*

 * CPU frequency scaling for Broadcom BMIPS SoCs

 *

 * Copyright (c) 2017 Broadcom

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License as

 * published by the Free Software Foundation version 2.

 *

 * This program is distributed "as is" WITHOUT ANY WARRANTY of any

 * kind, whether express or implied; without even the implied warranty

 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 */

​

#include <linux/cpufreq.h>

#include <linux/module.h>

#include <linux/of_address.h>

#include <linux/slab.h>

​

/* for mips_hpt_frequency */

#include <asm/time.h>

​

#define BMIPS_CPUFREQ_PREFIX    "bmips"

#define BMIPS_CPUFREQ_NAME  BMIPS_CPUFREQ_PREFIX "-cpufreq"

​

#define TRANSITION_LATENCY  (25 * 1000) /* 25 us */

​

#define BMIPS5_CLK_DIV_SET_SHIFT    0x7

#define BMIPS5_CLK_DIV_SHIFT        0x4

#define BMIPS5_CLK_DIV_MASK     0xf

​

enum bmips_type {

    BMIPS5000,

    BMIPS5200,

};

​

struct cpufreq_compat {

    const char *compatible;

    unsigned int bmips_type;

    unsigned int clk_mult;

    unsigned int max_freqs;

};

​

#define BMIPS(c, t, m, f) { \

    .compatible = c, \

    .bmips_type = (t), \

    .clk_mult = (m), \

    .max_freqs = (f), \

}

​

static struct cpufreq_compat bmips_cpufreq_compat[] = {

    BMIPS("brcm,bmips5000", BMIPS5000, 8, 4),

    BMIPS("brcm,bmips5200", BMIPS5200, 8, 4),

    { }

};

​

static struct cpufreq_compat *priv;

​

static int htp_freq_to_cpu_freq(unsigned int clk_mult)

{

    return mips_hpt_frequency * clk_mult / 1000;

}