arch/arm/mach-s5pv310/cpufreq.c

/* linux/arch/arm/mach-s5pv310/cpufreq.c
 *
 * Copyright (c) 2010 Samsung Electronics Co., Ltd.
 *		http://www.samsung.com
 *
 * S5PV310 - 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/types.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/regulator/consumer.h>
#include <linux/cpufreq.h>

#include <mach/map.h>
#include <mach/regs-clock.h>
#include <mach/regs-mem.h>

#include <plat/clock.h>

static struct clk *cpu_clk;
static struct clk *moutcore;
static struct clk *mout_mpll;
static struct clk *mout_apll;

#ifdef CONFIG_REGULATOR
static struct regulator *arm_regulator;
static struct regulator *int_regulator;
#endif

static struct cpufreq_freqs freqs;
static unsigned int armclk_use_apll;
static unsigned int memtype;

enum s5pv310_memory_type {
	DDR2 = 4,
	LPDDR2,
	DDR3,
};

enum cpufreq_level_index {
	L0, L1, L2, L3, L4, CPUFREQ_LEVEL_END,
};

static struct cpufreq_frequency_table s5pv310_freq_table[] = {
	{L0, 1000*1000},
	{L1, 800*1000},
	{L2, 400*1000},
	{L3, 200*1000},
	{L4, 100*1000},
	{0, CPUFREQ_TABLE_END},
};

static unsigned int clkdiv_cpu0[CPUFREQ_LEVEL_END + 1][7] = {
	/*
	 * Clock divider value for following
	 * { DIVCORE, DIVCOREM0, DIVCOREM1, DIVPERIPH,
	 *		DIVATB, DIVPCLK_DBG, DIVAPLL }
	 */

	/* ARM L0: 1000MHz */
	{ 0, 3, 7, 3, 3, 0, 0 },

	/* ARM L1: 800MHz */
	{ 0, 3, 7, 3, 3, 0, 0 },

	/* ARM L2: 400MHz */
	{ 1, 1, 3, 1, 1, 0, 0 },

	/* ARM L3: 200MHz */
	{ 3, 0, 1, 0, 0, 0, 0 },

	/* ARM L4A: 100MHz, for DDR2/3 */
	{ 7, 0, 1, 0, 0, 0, 0 },

	/* ARM L4B: 100MHz, for LPDDR2 (SMDKV310 has LPDDR2) */
	{ 7, 0, 1, 0, 0, 0, 0 },
};

static unsigned int clkdiv_dmc0[CPUFREQ_LEVEL_END + 1][8] = {
	/*
	 * Clock divider value for following
	 * { DIVACP, DIVACP_PCLK, DIVDPHY, DIVDMC, DIVDMCD
	 *		DIVDMCP, DIVCOPY2, DIVCORE_TIMERS }
	 */

	/* DMC L0: 400MHz */
	{ 3, 1, 1, 1, 1, 1, 3, 1 },

	/* DMC L1: 400MHz */
	{ 3, 1, 1, 1, 1, 1, 3, 1 },

	/* DMC L2: 400MHz */
	{ 3, 1, 1, 1, 1, 1, 3, 1 },

	/* DMC L3: 400MHz */
	{ 3, 1, 1, 1, 1, 1, 3, 1 },

	/* DMC L4A: 400MHz, for DDR2/3 */
	{ 7, 1, 1, 1, 1, 1, 3, 1 },

	/* DMC L4B: 200MHz, for LPDDR2 */
	{ 7, 1, 1, 3, 1, 1, 3, 1 },
};

static unsigned int clkdiv_top[CPUFREQ_LEVEL_END + 1][5] = {
	/*
	 * Clock divider value for following
	 * { DIVACLK200, DIVACLK100, DIVACLK160, DIVACLK133, DIVONENAND }
	 */

	/* ACLK200 L0: 200MHz */
	{ 3, 7, 4, 5, 1 },

	/* ACLK200 L1: 200MHz */
	{ 3, 7, 4, 5, 1 },

	/* ACLK200 L2: 200MHz */
	{ 3, 7, 4, 5, 1 },

	/* ACLK200 L3: 200MHz */
	{ 3, 7, 4, 5, 1 },

	/* ACLK200 L4A: 100MHz */
	{ 7, 7, 7, 7, 1 },

	/* ACLK200 L4B: 100MHz */
	{ 7, 7, 7, 7, 1 },
};

static unsigned int clkdiv_lr_bus[CPUFREQ_LEVEL_END + 1][2] = {
	/*
	 * Clock divider value for following
	 * { DIVGDL/R, DIVGPL/R }
	 */

	/* ACLK_GDL/R L0: 200MHz */
	{ 3, 1 },

	/* ACLK_GDL/R L1: 200MHz */
	{ 3, 1 },

	/* ACLK_GDL/R L2: 200MHz */
	{ 3, 1 },

	/* ACLK_GDL/R L3: 200MHz */
	{ 3, 1 },

	/* ACLK_GDL/R L4A: 100MHz */
	{ 7, 1 },

	/* ACLK_GDL/R L4B: 100MHz */
	{ 7, 1 },
};

struct cpufreq_voltage_table {
	unsigned int	index;		/* any */
	unsigned int	arm_volt;	/* uV */
	unsigned int	int_volt;
};

static struct cpufreq_voltage_table s5pv310_volt_table[] = {
	{
		.index		= L0,
		.arm_volt	= 1200000,
		.int_volt	= 1100000,
	}, {
		.index		= L1,
		.arm_volt	= 1100000,
		.int_volt	= 1100000,
	}, {
		.index		= L2,
		.arm_volt	= 1050000,
		.int_volt	= 1100000,
	}, {
		.index		= L3,
		.arm_volt	= 1050000,
		.int_volt	= 1100000,
	}, {
		.index		= L4,
		.arm_volt	= 1000000,
		.int_volt	= 1000000,
	},
};

int s5pv310_verify_speed(struct cpufreq_policy *policy)
{
	return cpufreq_frequency_table_verify(policy, s5pv310_freq_table);
}

unsigned int s5pv310_getspeed(unsigned int cpu)
{
	return clk_get_rate(cpu_clk) / 1000;
}

void s5pv310_set_clkdiv(unsigned int div_index)
{
	unsigned int tmp;

	/* Change Divider - CPU0 */

	tmp = __raw_readl(S5P_CLKDIV_CPU);

	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[div_index][0] << S5P_CLKDIV_CPU0_CORE_SHIFT) |
		(clkdiv_cpu0[div_index][1] << S5P_CLKDIV_CPU0_COREM0_SHIFT) |
		(clkdiv_cpu0[div_index][2] << S5P_CLKDIV_CPU0_COREM1_SHIFT) |
		(clkdiv_cpu0[div_index][3] << S5P_CLKDIV_CPU0_PERIPH_SHIFT) |
		(clkdiv_cpu0[div_index][4] << S5P_CLKDIV_CPU0_ATB_SHIFT) |
		(clkdiv_cpu0[div_index][5] << S5P_CLKDIV_CPU0_PCLKDBG_SHIFT) |
		(clkdiv_cpu0[div_index][6] << S5P_CLKDIV_CPU0_APLL_SHIFT));

	__raw_writel(tmp, S5P_CLKDIV_CPU);

	do {
		tmp = __raw_readl(S5P_CLKDIV_STATCPU);
	} while (tmp & 0x1111111);

	/* Change Divider - DMC0 */

	tmp = __raw_readl(S5P_CLKDIV_DMC0);

	tmp &= ~(S5P_CLKDIV_DMC0_ACP_MASK | S5P_CLKDIV_DMC0_ACPPCLK_MASK |
		S5P_CLKDIV_DMC0_DPHY_MASK | S5P_CLKDIV_DMC0_DMC_MASK |
		S5P_CLKDIV_DMC0_DMCD_MASK | S5P_CLKDIV_DMC0_DMCP_MASK |
		S5P_CLKDIV_DMC0_COPY2_MASK | S5P_CLKDIV_DMC0_CORETI_MASK);

	tmp |= ((clkdiv_dmc0[div_index][0] << S5P_CLKDIV_DMC0_ACP_SHIFT) |
		(clkdiv_dmc0[div_index][1] << S5P_CLKDIV_DMC0_ACPPCLK_SHIFT) |
		(clkdiv_dmc0[div_index][2] << S5P_CLKDIV_DMC0_DPHY_SHIFT) |
		(clkdiv_dmc0[div_index][3] << S5P_CLKDIV_DMC0_DMC_SHIFT) |
		(clkdiv_dmc0[div_index][4] << S5P_CLKDIV_DMC0_DMCD_SHIFT) |
		(clkdiv_dmc0[div_index][5] << S5P_CLKDIV_DMC0_DMCP_SHIFT) |
		(clkdiv_dmc0[div_index][6] << S5P_CLKDIV_DMC0_COPY2_SHIFT) |
		(clkdiv_dmc0[div_index][7] << S5P_CLKDIV_DMC0_CORETI_SHIFT));

	__raw_writel(tmp, S5P_CLKDIV_DMC0);

	do {
		tmp = __raw_readl(S5P_CLKDIV_STAT_DMC0);
	} while (tmp & 0x11111111);

	/* Change Divider - TOP */

	tmp = __raw_readl(S5P_CLKDIV_TOP);

	tmp &= ~(S5P_CLKDIV_TOP_ACLK200_MASK | S5P_CLKDIV_TOP_ACLK100_MASK |
		S5P_CLKDIV_TOP_ACLK160_MASK | S5P_CLKDIV_TOP_ACLK133_MASK |
		S5P_CLKDIV_TOP_ONENAND_MASK);

	tmp |= ((clkdiv_top[div_index][0] << S5P_CLKDIV_TOP_ACLK200_SHIFT) |
		(clkdiv_top[div_index][1] << S5P_CLKDIV_TOP_ACLK100_SHIFT) |
		(clkdiv_top[div_index][2] << S5P_CLKDIV_TOP_ACLK160_SHIFT) |
		(clkdiv_top[div_index][3] << S5P_CLKDIV_TOP_ACLK133_SHIFT) |
		(clkdiv_top[div_index][4] << S5P_CLKDIV_TOP_ONENAND_SHIFT));

	__raw_writel(tmp, S5P_CLKDIV_TOP);

	do {
		tmp = __raw_readl(S5P_CLKDIV_STAT_TOP);
	} while (tmp & 0x11111);

	/* Change Divider - LEFTBUS */

	tmp = __raw_readl(S5P_CLKDIV_LEFTBUS);

	tmp &= ~(S5P_CLKDIV_BUS_GDLR_MASK | S5P_CLKDIV_BUS_GPLR_MASK);

	tmp |= ((clkdiv_lr_bus[div_index][0] << S5P_CLKDIV_BUS_GDLR_SHIFT) |
		(clkdiv_lr_bus[div_index][1] << S5P_CLKDIV_BUS_GPLR_SHIFT));

	__raw_writel(tmp, S5P_CLKDIV_LEFTBUS);

	do {
		tmp = __raw_readl(S5P_CLKDIV_STAT_LEFTBUS);
	} while (tmp & 0x11);

	/* Change Divider - RIGHTBUS */

	tmp = __raw_readl(S5P_CLKDIV_RIGHTBUS);

	tmp &= ~(S5P_CLKDIV_BUS_GDLR_MASK | S5P_CLKDIV_BUS_GPLR_MASK);

	tmp |= ((clkdiv_lr_bus[div_index][0] << S5P_CLKDIV_BUS_GDLR_SHIFT) |
		(clkdiv_lr_bus[div_index][1] << S5P_CLKDIV_BUS_GPLR_SHIFT));

	__raw_writel(tmp, S5P_CLKDIV_RIGHTBUS);

	do {
		tmp = __raw_readl(S5P_CLKDIV_STAT_RIGHTBUS);
	} while (tmp & 0x11);
}

static int s5pv310_target(struct cpufreq_policy *policy,
			  unsigned int target_freq,
			  unsigned int relation)
{
	unsigned int index, div_index, tmp;
	unsigned int arm_volt, int_volt;
	unsigned int need_apll = 0;

	freqs.old = s5pv310_getspeed(policy->cpu);

	if (cpufreq_frequency_table_target(policy, s5pv310_freq_table,
					   target_freq, relation, &index))
		return -EINVAL;

	freqs.new = s5pv310_freq_table[index].frequency;
	freqs.cpu = policy->cpu;

	if (freqs.new == freqs.old)
		return 0;

	/*
	 * If freqs.new is higher than 800MHz
	 * cpufreq driver should turn on apll
	 */
	if (index < L1)
		need_apll = 1;

	/* If the memory type is LPDDR2, use L4-B instead of L4-A */
	if ((index == L4) && (memtype == LPDDR2))
		div_index = index + 1;
	else
		div_index = index;

	/* get the voltage value */
	arm_volt = s5pv310_volt_table[index].arm_volt;
	int_volt = s5pv310_volt_table[index].int_volt;

	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);

	/* control regulator */
	if (freqs.new > freqs.old) {
		/* Voltage up */
#ifdef CONFIG_REGULATOR
		regulator_set_voltage(arm_regulator, arm_volt, arm_volt);
		regulator_set_voltage(int_regulator, int_volt, int_volt);
#endif
	}

	/* Clock Configuration Procedure */

	/* 1. Change the system clock divider values */
	s5pv310_set_clkdiv(div_index);

	/* 2. Change the divider values for special clocks in CMU_TOP */
	/* currently nothing */

	/* 3. Change the XPLL values or Select the parent XPLL */
	if (need_apll) {
		if (!armclk_use_apll) {
			/*
			 * If the parent clock of armclk isn't apll
			 * here need to set apll (include m,p,s value)
			 */

			/* a. 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);

			/* b. Set APLL Lock time */
			__raw_writel(S5P_APLL_LOCKTIME, S5P_APLL_LOCK);

			/* c. Change PLL PMS values */
			__raw_writel(S5P_APLL_VAL_1000, S5P_APLL_CON0);

			/* d. Turn on a PLL */
			tmp = __raw_readl(S5P_APLL_CON0);
			tmp |= (0x1 << S5P_APLLCON0_ENABLE_SHIFT);
			__raw_writel(tmp, S5P_APLL_CON0);

			/* e. wait_lock_time */
			do {
				tmp = __raw_readl(S5P_APLL_CON0);
			} while (!(tmp & (0x1 << S5P_APLLCON0_LOCKED_SHIFT)));

			armclk_use_apll = 1;

		}

		/* 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));

	} else {
		if (clk_get_parent(moutcore) != mout_mpll) {
			clk_set_parent(moutcore, mout_mpll);

			do {
				tmp = __raw_readl(S5P_CLKMUX_STATCPU);
				tmp &= S5P_CLKMUX_STATCPU_MUXCORE_MASK;
			} while (tmp != (0x2 << S5P_CLKSRC_CPU_MUXCORE_SHIFT));
		}
	}

	/* control regulator */
	if (freqs.new < freqs.old) {
		/* Voltage down */
#ifdef CONFIG_REGULATOR
		regulator_set_voltage(arm_regulator, arm_volt, arm_volt);
		regulator_set_voltage(int_regulator, int_volt, int_volt);
#endif
	}

	cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);

	return 0;
}

#ifdef CONFIG_PM
static int s5pv310_cpufreq_suspend(struct cpufreq_policy *policy,
				   pm_message_t pmsg)
{
	return 0;
}

static int s5pv310_cpufreq_resume(struct cpufreq_policy *policy)
{
	return 0;
}
#endif

static int s5pv310_cpufreq_cpu_init(struct cpufreq_policy *policy)
{
	policy->cur = policy->min = policy->max = s5pv310_getspeed(policy->cpu);

	cpufreq_frequency_table_get_attr(s5pv310_freq_table, policy->cpu);

	/* set the transition latency value */
	policy->cpuinfo.transition_latency = 100000;

	/*
	 * S5PV310 multi-core processors has 2 cores
	 * that the frequency cannot be set independently.
	 * Each cpu is bound to the same speed.
	 * So the affected cpu is all of the cpus.
	 */
	cpumask_setall(policy->cpus);

	return cpufreq_frequency_table_cpuinfo(policy, s5pv310_freq_table);
}

static struct cpufreq_driver s5pv310_driver = {
	.flags		= CPUFREQ_STICKY,
	.verify		= s5pv310_verify_speed,
	.target		= s5pv310_target,
	.get		= s5pv310_getspeed,
	.init		= s5pv310_cpufreq_cpu_init,
	.name		= "s5pv310_cpufreq",
#ifdef CONFIG_PM
	.suspend	= s5pv310_cpufreq_suspend,
	.resume		= s5pv310_cpufreq_resume,
#endif
};

static int __init s5pv310_cpufreq_init(void)
{
	unsigned int tmp;

	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 out;

	mout_mpll = clk_get(NULL, "mout_mpll");
	if (IS_ERR(mout_mpll))
		goto out;

	mout_apll = clk_get(NULL, "mout_apll");
	if (IS_ERR(mout_apll))
		goto out;

#ifdef CONFIG_REGULATOR
	arm_regulator = regulator_get(NULL, "vdd_arm");
	if (IS_ERR(arm_regulator)) {
		printk(KERN_ERR "failed to get resource %s\n", "vdd_arm");
		goto out;
	}

	int_regulator = regulator_get(NULL, "vdd_int");
	if (IS_ERR(int_regulator)) {
		printk(KERN_ERR "failed to get resource %s\n", "vdd_int");
		goto out;
	}
#endif

	/* check parent clock of armclk */
	tmp = __raw_readl(S5P_CLKSRC_CPU);
	if (tmp & S5P_CLKSRC_CPU_MUXCORE_SHIFT)
		armclk_use_apll = 0;
	else
		armclk_use_apll = 1;

	/*
	 * Check DRAM type.
	 * Because DVFS level is different according to DRAM type.
	 */
	memtype = __raw_readl(S5P_VA_DMC0 + S5P_DMC0_MEMCON_OFFSET);
	memtype = (memtype >> S5P_DMC0_MEMTYPE_SHIFT);
	memtype &= S5P_DMC0_MEMTYPE_MASK;

	if ((memtype < DDR2) && (memtype > DDR3)) {
		printk(KERN_ERR "%s: wrong memtype= 0x%x\n", __func__, memtype);
		goto out;
	} else {
		printk(KERN_DEBUG "%s: memtype= 0x%x\n", __func__, memtype);
	}

	return cpufreq_register_driver(&s5pv310_driver);

out:
	if (!IS_ERR(cpu_clk))
		clk_put(cpu_clk);

	if (!IS_ERR(moutcore))
		clk_put(moutcore);

	if (!IS_ERR(mout_mpll))
		clk_put(mout_mpll);

	if (!IS_ERR(mout_apll))
		clk_put(mout_apll);

#ifdef CONFIG_REGULATOR
	if (!IS_ERR(arm_regulator))
		regulator_put(arm_regulator);

	if (!IS_ERR(int_regulator))
		regulator_put(int_regulator);
#endif

	printk(KERN_ERR "%s: failed initialization\n", __func__);

	return -EINVAL;
}
late_initcall(s5pv310_cpufreq_init);