- 根目录:
- drivers
- cpufreq
- exynos4210-cpufreq.c
/*
* Copyright (c) 2010-2011 Samsung Electronics Co., Ltd.
* http://www.samsung.com
*
* EXYNOS4210 - 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 <mach/regs-clock.h>
#include <mach/cpufreq.h>
#define CPUFREQ_LEVEL_END L5
static int max_support_idx = L0;
static int min_support_idx = (CPUFREQ_LEVEL_END - 1);
static struct clk *cpu_clk;
static struct clk *moutcore;
static struct clk *mout_mpll;
static struct clk *mout_apll;
struct cpufreq_clkdiv {
unsigned int index;
unsigned int clkdiv;
};
static unsigned int exynos4210_volt_table[CPUFREQ_LEVEL_END] = {
1250000, 1150000, 1050000, 975000, 950000,
};
static struct cpufreq_clkdiv exynos4210_clkdiv_table[CPUFREQ_LEVEL_END];
static struct cpufreq_frequency_table exynos4210_freq_table[] = {
{L0, 1200*1000},
{L1, 1000*1000},
{L2, 800*1000},
{L3, 500*1000},
{L4, 200*1000},
{0, CPUFREQ_TABLE_END},
};
static unsigned int clkdiv_cpu0[CPUFREQ_LEVEL_END][7] = {
/*
* Clock divider value for following
* { DIVCORE, DIVCOREM0, DIVCOREM1, DIVPERIPH,
* DIVATB, DIVPCLK_DBG, DIVAPLL }
*/
/* ARM L0: 1200MHz */
{ 0, 3, 7, 3, 4, 1, 7 },
/* ARM L1: 1000MHz */
{ 0, 3, 7, 3, 4, 1, 7 },
/* ARM L2: 800MHz */
{ 0, 3, 7, 3, 3, 1, 7 },
/* ARM L3: 500MHz */
{ 0, 3, 7, 3, 3, 1, 7 },
/* ARM L4: 200MHz */
{ 0, 1, 3, 1, 3, 1, 0 },
};
static unsigned int clkdiv_cpu1[CPUFREQ_LEVEL_END][2] = {
/*
* Clock divider value for following
* { DIVCOPY, DIVHPM }
*/
/* ARM L0: 1200MHz */
{ 5, 0 },
/* ARM L1: 1000MHz */
{ 4, 0 },
/* ARM L2: 800MHz */
{ 3, 0 },
/* ARM L3: 500MHz */
{ 3, 0 },
/* ARM L4: 200MHz */
{ 3, 0 },
};
static unsigned int exynos4210_apll_pms_table[CPUFREQ_LEVEL_END] = {
/* APLL FOUT L0: 1200MHz */
((150 << 16) | (3 << 8) | 1),
/* APLL FOUT L1: 1000MHz */
((250 << 16) | (6 << 8) | 1),
/* APLL FOUT L2: 800MHz */
((200 << 16) | (6 << 8) | 1),
/* APLL FOUT L3: 500MHz */
((250 << 16) | (6 << 8) | 2),
/* APLL FOUT L4: 200MHz */
((200 << 16) | (6 << 8) | 3),
};
static void exynos4210_set_clkdiv(unsigned int div_index)
{
unsigned int tmp;
/* Change Divider - CPU0 */
tmp = exynos4210_clkdiv_table[div_index].clkdiv;
__raw_writel(tmp, S5P_CLKDIV_CPU);
do {
tmp = __raw_readl(S5P_CLKDIV_STATCPU);
} while (tmp & 0x1111111);
/* Change Divider - CPU1 */
tmp = __raw_readl(S5P_CLKDIV_CPU1);
tmp &= ~((0x7 << 4) | 0x7);
tmp |= ((clkdiv_cpu1[div_index][0] << 4) |
(clkdiv_cpu1[div_index][1] << 0));
__raw_writel(tmp, S5P_CLKDIV_CPU1);
do {
tmp = __raw_readl(S5P_CLKDIV_STATCPU1);
} while (tmp & 0x11);
}
static void exynos4210_set_apll(unsigned int index)
{
unsigned int tmp;
/* 1. MUX_CORE_SEL = MPLL, ARMCLK uses MPLL for lock time */
clk_set_parent(moutcore, mout_mpll);
do {
tmp = (__raw_readl(S5P_CLKMUX_STATCPU)
>> S5P_CLKSRC_CPU_MUXCORE_SHIFT);
tmp &= 0x7;
} while (tmp != 0x2);
/* 2. Set APLL Lock time */
__raw_writel(S5P_APLL_LOCKTIME, S5P_APLL_LOCK);
/* 3. Change PLL PMS values */
tmp = __raw_readl(S5P_APLL_CON0);
tmp &= ~((0x3ff << 16) | (0x3f << 8) | (0x7 << 0));
tmp |= exynos4210_apll_pms_table[index];
__raw_writel(tmp, S5P_APLL_CON0);
/* 4. wait_lock_time */
do {
tmp = __raw_readl(S5P_APLL_CON0);
} while (!(tmp & (0x1 << S5P_APLLCON0_LOCKED_SHIFT)));
/* 5. MUX_CORE_SEL = APLL */
clk_set_parent(moutcore, mout_apll);
do {
tmp = __raw_readl(S5P_CLKMUX_STATCPU);
tmp &= S5P_CLKMUX_STATCPU_MUXCORE_MASK;
} while (tmp != (0x1 << S5P_CLKSRC_CPU_MUXCORE_SHIFT));
}
bool exynos4210_pms_change(unsigned int old_index, unsigned int new_index)
{
unsigned int old_pm = (exynos4210_apll_pms_table[old_index] >> 8);
unsigned int new_pm = (exynos4210_apll_pms_table[new_index] >> 8);
return (old_pm == new_pm) ? 0 : 1;
}
static void exynos4210_set_frequency(unsigned int old_index,
unsigned int new_index)
{
unsigned int tmp;
if (old_index > new_index) {
if (!exynos4210_pms_change(old_index, new_index)) {
/* 1. Change the system clock divider values */
exynos4210_set_clkdiv(new_index);
/* 2. Change just s value in apll m,p,s value */
tmp = __raw_readl(S5P_APLL_CON0);
tmp &= ~(0x7 << 0);
tmp |= (exynos4210_apll_pms_table[new_index] & 0x7);
__raw_writel(tmp, S5P_APLL_CON0);
} else {
/* Clock Configuration Procedure */
/* 1. Change the system clock divider values */
exynos4210_set_clkdiv(new_index);
/* 2. Change the apll m,p,s value */
exynos4210_set_apll(new_index);
}
} else if (old_index < new_index) {
if (!exynos4210_pms_change(old_index, new_index)) {
/* 1. Change just s value in apll m,p,s value */
tmp = __raw_readl(S5P_APLL_CON0);
tmp &= ~(0x7 << 0);
tmp |= (exynos4210_apll_pms_table[new_index] & 0x7);
__raw_writel(tmp, S5P_APLL_CON0);
/* 2. Change the system clock divider values */
exynos4210_set_clkdiv(new_index);
} else {
/* Clock Configuration Procedure */
/* 1. Change the apll m,p,s value */
exynos4210_set_apll(new_index);
/* 2. Change the system clock divider values */
exynos4210_set_clkdiv(new_index);
}
}
}
int exynos4210_cpufreq_init(struct exynos_dvfs_info *info)
{
int i;
unsigned int tmp;
unsigned long rate;
cpu_clk = clk_get(NULL, "armclk");
if (IS_ERR(cpu_clk))
return PTR_ERR(cpu_clk);
moutcore = clk_get(NULL, "moutcore");
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;
tmp = __raw_readl(S5P_CLKDIV_CPU);
for (i = L0; i < CPUFREQ_LEVEL_END; i++) {
tmp &= ~(S5P_CLKDIV_CPU0_CORE_MASK |
S5P_CLKDIV_CPU0_COREM0_MASK |
S5P_CLKDIV_CPU0_COREM1_MASK |
S5P_CLKDIV_CPU0_PERIPH_MASK |
S5P_CLKDIV_CPU0_ATB_MASK |
S5P_CLKDIV_CPU0_PCLKDBG_MASK |
S5P_CLKDIV_CPU0_APLL_MASK);
tmp |= ((clkdiv_cpu0[i][0] << S5P_CLKDIV_CPU0_CORE_SHIFT) |
(clkdiv_cpu0[i][1] << S5P_CLKDIV_CPU0_COREM0_SHIFT) |
(clkdiv_cpu0[i][2] << S5P_CLKDIV_CPU0_COREM1_SHIFT) |
(clkdiv_cpu0[i][3] << S5P_CLKDIV_CPU0_PERIPH_SHIFT) |
(clkdiv_cpu0[i][4] << S5P_CLKDIV_CPU0_ATB_SHIFT) |
(clkdiv_cpu0[i][5] << S5P_CLKDIV_CPU0_PCLKDBG_SHIFT) |
(clkdiv_cpu0[i][6] << S5P_CLKDIV_CPU0_APLL_SHIFT));
exynos4210_clkdiv_table[i].clkdiv = tmp;
}
info->mpll_freq_khz = rate;
info->pm_lock_idx = L2;
info->pll_safe_idx = L2;
info->max_support_idx = max_support_idx;
info->min_support_idx = min_support_idx;
info->cpu_clk = cpu_clk;
info->volt_table = exynos4210_volt_table;
info->freq_table = exynos4210_freq_table;
info->set_freq = exynos4210_set_frequency;
info->need_apll_change = exynos4210_pms_change;
return 0;
err_mout_apll:
if (!IS_ERR(mout_mpll))
clk_put(mout_mpll);
err_mout_mpll:
if (!IS_ERR(moutcore))
clk_put(moutcore);
err_moutcore:
if (!IS_ERR(cpu_clk))
clk_put(cpu_clk);
pr_debug("%s: failed initialization\n", __func__);
return -EINVAL;
}
EXPORT_SYMBOL(exynos4210_cpufreq_init);