/*
* Copyright (c) 2010-20122Samsung Electronics Co., Ltd.
* http://www.samsung.com
*
* EXYNOS5250 - CPU frequency scaling support
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/cpufreq.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include "exynos-cpufreq.h"
static struct clk *cpu_clk;
static struct clk *moutcore;
static struct clk *mout_mpll;
static struct clk *mout_apll;
static struct exynos_dvfs_info *cpufreq;
static unsigned int exynos5250_volt_table[] = {
1300000, 1250000, 1225000, 1200000, 1150000,
1125000, 1100000, 1075000, 1050000, 1025000,
1012500, 1000000, 975000, 950000, 937500,
925000
};
static struct cpufreq_frequency_table exynos5250_freq_table[] = {
{0, L0, 1700 * 1000},
{0, L1, 1600 * 1000},
{0, L2, 1500 * 1000},
{0, L3, 1400 * 1000},
{0, L4, 1300 * 1000},
{0, L5, 1200 * 1000},
{0, L6, 1100 * 1000},
{0, L7, 1000 * 1000},
{0, L8, 900 * 1000},
{0, L9, 800 * 1000},
{0, L10, 700 * 1000},
{0, L11, 600 * 1000},
{0, L12, 500 * 1000},
{0, L13, 400 * 1000},
{0, L14, 300 * 1000},
{0, L15, 200 * 1000},
{0, 0, CPUFREQ_TABLE_END},
};
static struct apll_freq apll_freq_5250[] = {
/*
* values:
* freq
* clock divider for ARM, CPUD, ACP, PERIPH, ATB, PCLK_DBG, APLL, ARM2
* clock divider for COPY, HPM, RESERVED
* PLL M, P, S
*/
APLL_FREQ(1700, 0, 3, 7, 7, 7, 3, 5, 0, 0, 2, 0, 425, 6, 0),
APLL_FREQ(1600, 0, 3, 7, 7, 7, 1, 4, 0, 0, 2, 0, 200, 3, 0),
APLL_FREQ(1500, 0, 2, 7, 7, 7, 1, 4, 0, 0, 2, 0, 250, 4, 0),
APLL_FREQ(1400, 0, 2, 7, 7, 6, 1, 4, 0, 0, 2, 0, 175, 3, 0),
APLL_FREQ(1300, 0, 2, 7, 7, 6, 1, 3, 0, 0, 2, 0, 325, 6, 0),
APLL_FREQ(1200, 0, 2, 7, 7, 5, 1, 3, 0, 0, 2, 0, 200, 4, 0),
APLL_FREQ(1100, 0, 3, 7, 7, 5, 1, 3, 0, 0, 2, 0, 275, 6, 0),
APLL_FREQ(1000, 0, 1, 7, 7, 4, 1, 2, 0, 0, 2, 0, 125, 3, 0),
APLL_FREQ(900, 0, 1, 7, 7, 4, 1, 2, 0, 0, 2, 0, 150, 4, 0),
APLL_FREQ(800, 0, 1, 7, 7, 4, 1, 2, 0, 0, 2, 0, 100, 3, 0),
APLL_FREQ(700, 0, 1, 7, 7, 3, 1, 1, 0, 0, 2, 0, 175, 3, 1),
APLL_FREQ(600, 0, 1, 7, 7, 3, 1, 1, 0, 0, 2, 0, 200, 4, 1),
APLL_FREQ(500, 0, 1, 7, 7, 2, 1, 1, 0, 0, 2, 0, 125, 3, 1),
APLL_FREQ(400, 0, 1, 7, 7, 2, 1, 1, 0, 0, 2, 0, 100, 3, 1),
APLL_FREQ(300, 0, 1, 7, 7, 1, 1, 1, 0, 0, 2, 0, 200, 4, 2),
APLL_FREQ(200, 0, 1, 7, 7, 1, 1, 1, 0, 0, 2, 0, 100, 3, 2),
};
static void set_clkdiv(unsigned int div_index)
{
unsigned int tmp;
/* Change Divider - CPU0 */
tmp = apll_freq_5250[div_index].clk_div_cpu0;
__raw_writel(tmp, cpufreq->cmu_regs + EXYNOS5_CLKDIV_CPU0);
while (__raw_readl(cpufreq->cmu_regs + EXYNOS5_CLKDIV_STATCPU0)
& 0x11111111)
cpu_relax();
/* Change Divider - CPU1 */
tmp = apll_freq_5250[div_index].clk_div_cpu1;
__raw_writel(tmp, cpufreq->cmu_regs + EXYNOS5_CLKDIV_CPU1);
while (__raw_readl(cpufreq->cmu_regs + EXYNOS5_CLKDIV_STATCPU1) & 0x11)
cpu_relax();
}
static void set_apll(unsigned int index)
{
unsigned int tmp;
unsigned int freq = apll_freq_5250[index].freq;
/* MUX_CORE_SEL = MPLL, ARMCLK uses MPLL for lock time */
clk_set_parent(moutcore, mout_mpll);
do {
cpu_relax();
tmp = (__raw_readl(cpufreq->cmu_regs + EXYNOS5_CLKMUX_STATCPU)
>> 16);
tmp &= 0x7;
} while (tmp != 0x2);
clk_set_rate(mout_apll, freq * 1000);
/* MUX_CORE_SEL = APLL */
clk_set_parent(moutcore, mout_apll);
do {
cpu_relax();
tmp = __raw_readl(cpufreq->cmu_regs + EXYNOS5_CLKMUX_STATCPU);
tmp &= (0x7 << 16);
} while (tmp != (0x1 << 16));
}
static void exynos5250_set_frequency(unsigned int old_index,
unsigned int new_index)
{
if (old_index > new_index) {
set_clkdiv(new_index);
set_apll(new_index);
} else if (old_index < new_index) {
set_apll(new_index);
set_clkdiv(new_index);
}
}
int exynos5250_cpufreq_init(struct exynos_dvfs_info *info)
{
struct device_node *np;
unsigned long rate;
/*
* HACK: This is a temporary workaround to get access to clock
* controller registers directly and remove static mappings and
* dependencies on platform headers. It is necessary to enable
* Exynos multi-platform support and will be removed together with
* this whole driver as soon as Exynos gets migrated to use
* cpufreq-dt driver.
*/
np = of_find_compatible_node(NULL, NULL, "samsung,exynos5250-clock");
if (!np) {
pr_err("%s: failed to find clock controller DT node\n",
__func__);
return -ENODEV;
}
info->cmu_regs = of_iomap(np, 0);
if (!info->cmu_regs) {
pr_err("%s: failed to map CMU registers\n", __func__);
return -EFAULT;
}
cpu_clk = clk_get(NULL, "armclk");
if (IS_ERR(cpu_clk))
return PTR_ERR(cpu_clk);
moutcore = clk_get(NULL, "mout_cpu");
if (IS_ERR(moutcore))
goto err_moutcore;
mout_mpll = clk_get(NULL, "mout_mpll");
if (IS_ERR(mout_mpll))
goto err_mout_mpll;
rate = clk_get_rate(mout_mpll) / 1000;
mout_apll = clk_get(NULL, "mout_apll");
if (IS_ERR(mout_apll))
goto err_mout_apll;
info->mpll_freq_khz = rate;
/* 800Mhz */
info->pll_safe_idx = L9;
info->cpu_clk = cpu_clk;
info->volt_table = exynos5250_volt_table;
info->freq_table = exynos5250_freq_table;
info->set_freq = exynos5250_set_frequency;
cpufreq = info;
return 0;
err_mout_apll:
clk_put(mout_mpll);
err_mout_mpll:
clk_put(moutcore);
err_moutcore:
clk_put(cpu_clk);
pr_err("%s: failed initialization\n", __func__);
return -EINVAL;
}
