[PATCH v4 7/7] ARM: S5PV210: Initial CPUFREQ Support

MyungJoo Ham myungjoo.ham at samsung.com
Thu Jul 22 05:22:53 EDT 2010


S5PV210 CPUFREQ Support.

This CPUFREQ may work without PMIC's DVS support. However, it is not
as effective without DVS support as supposed. AVS is not supported in
this version.

Note that CLK_SRC of some clocks including ARMCLK, G3D, G2D, MFC,
and ONEDRAM are modified directly without updating clksrc_src
representations of the clocks.  Because CPUFREQ reverts the CLK_SRC
to the supposed values, this does not affect the consistency as long as
there are no other modules that modifies clock sources of ARMCLK, G3D,
G2D, MFC, and ONEDRAM (and only CPUFREQ should have the control). As
soon as clock framework is settled, we may update source clocks
(.parent field) of those clocks accordingly later.

Signed-off-by: MyungJoo Ham <myungjoo.ham at samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
--
v2:
	- Ramp-up delay is removed. (let regulator framework do the job)
	- Provide proper max values for regulator_set_voltage
	- Removed unneccesary #ifdef's.
	- Removed unnecessary initialiser for CLK_OUT
v3:
	- Style corrections (pr_info/pr_err, ...)
	- Revised dvs_conf struct
v4:
	- Renamed cpufreq-s5pv210.c -> cpufreq.c
	- Style corrections (less #ifdef's, comments)
	- Removed unncessary codes
	- Remove #ifdef for WORKAROUND, use s5pv210_workaround()
	- Renamed some static variables (get rid of s5pv210 prefix)
	- Added machine dependency to Kconfig/Makefile
	- DMC0, DMC1 refresh counter is not updated by a hardcoded value, but
	with the value given as the default and relative clock speeds. Besides,
	the algorithm to update DMC0/1 refresh counter is reformed.

---
 arch/arm/Kconfig                              |    1 +
 arch/arm/mach-s5pv210/Kconfig                 |    5 +
 arch/arm/mach-s5pv210/Makefile                |    2 +
 arch/arm/mach-s5pv210/cpufreq.c               |  783 +++++++++++++++++++++++++
 arch/arm/mach-s5pv210/include/mach/cpu-freq.h |   40 ++
 5 files changed, 831 insertions(+), 0 deletions(-)
 create mode 100644 arch/arm/mach-s5pv210/cpufreq.c
 create mode 100644 arch/arm/mach-s5pv210/include/mach/cpu-freq.h

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 98922f7..d5a5916 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -701,6 +701,7 @@ config ARCH_S5PV210
 	select HAVE_CLK
 	select ARM_L1_CACHE_SHIFT_6
 	select ARCH_USES_GETTIMEOFFSET
+	select ARCH_HAS_CPUFREQ
 	help
 	  Samsung S5PV210/S5PC110 series based systems
 
diff --git a/arch/arm/mach-s5pv210/Kconfig b/arch/arm/mach-s5pv210/Kconfig
index 631019a..1c6d3bc 100644
--- a/arch/arm/mach-s5pv210/Kconfig
+++ b/arch/arm/mach-s5pv210/Kconfig
@@ -14,6 +14,7 @@ config CPU_S5PV210
 	select PLAT_S5P
 	select S3C_PL330_DMA
 	select S5P_EXT_INT
+	select S5PV210_CPU_FREQ if CPU_FREQ
 	help
 	  Enable S5PV210 CPU support
 
@@ -101,4 +102,8 @@ config MACH_SMDKC110
 	  Machine support for Samsung SMDKC110
 	  S5PC110(MCP) is one of package option of S5PV210
 
+config S5PV210_CPU_FREQ
+	bool "S5PV210 CPU-FREQ Support"
+	depends on CPU_S5PV210 && CPU_FREQ
+
 endif
diff --git a/arch/arm/mach-s5pv210/Makefile b/arch/arm/mach-s5pv210/Makefile
index aae592a..72ca5ec 100644
--- a/arch/arm/mach-s5pv210/Makefile
+++ b/arch/arm/mach-s5pv210/Makefile
@@ -34,3 +34,5 @@ obj-$(CONFIG_S5PV210_SETUP_I2C2) 	+= setup-i2c2.o
 obj-$(CONFIG_S5PV210_SETUP_KEYPAD)	+= setup-keypad.o
 obj-$(CONFIG_S5PV210_SETUP_SDHCI)       += setup-sdhci.o
 obj-$(CONFIG_S5PV210_SETUP_SDHCI_GPIO)	+= setup-sdhci-gpio.o
+
+obj-$(CONFIG_S5PV210_CPU_FREQ)		+= cpufreq.o
diff --git a/arch/arm/mach-s5pv210/cpufreq.c b/arch/arm/mach-s5pv210/cpufreq.c
new file mode 100644
index 0000000..8ea1ce8
--- /dev/null
+++ b/arch/arm/mach-s5pv210/cpufreq.c
@@ -0,0 +1,783 @@
+/*  linux/arch/arm/mach-s5pv210/cpufreq.c
+ *
+ *  Copyright (C) 2010 Samsung Electronics Co., Ltd.
+ *
+ *  CPU frequency scaling for S5PV210/S5PC110
+ *  Based on cpu-sa1110.c and s5pc11x-cpufreq.c
+ *
+ * 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/sched.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/regulator/consumer.h>
+#include <linux/gpio.h>
+#include <asm/system.h>
+
+#include <mach/hardware.h>
+#include <mach/map.h>
+#include <mach/regs-clock.h>
+#include <mach/regs-gpio.h>
+#include <mach/cpu-freq.h>
+
+#include <plat/cpu-freq.h>
+#include <plat/pll.h>
+#include <plat/clock.h>
+#include <plat/gpio-cfg.h>
+#include <plat/regs-fb.h>
+#ifdef CONFIG_PM
+#include <plat/pm.h>
+#endif
+
+static struct clk *mpu_clk;
+static struct regulator *arm_regulator;
+static struct regulator *internal_regulator;
+
+struct s3c_cpufreq_freqs s3c_freqs;
+
+static unsigned long previous_arm_volt;
+
+static unsigned int backup_dmc0_reg;
+static unsigned int backup_dmc1_reg;
+static unsigned int backup_freq_level;
+static unsigned int mpll_freq; /* in MHz */
+static unsigned int apll_freq_max; /* in MHz */
+
+/* frequency */
+static struct cpufreq_frequency_table freq_table[] = {
+	{L0, 1000*1000},
+	{L1, 800*1000},
+	{L2, 400*1000},
+	{L3, 200*1000},
+	{L4, 100*1000},
+	{0, CPUFREQ_TABLE_END},
+};
+
+struct s5pv210_dvs_conf {
+	unsigned long       arm_volt;   /* uV */
+	unsigned long       int_volt;   /* uV */
+};
+
+const unsigned long arm_volt_max = 1350000;
+const unsigned long int_volt_max = 1250000;
+
+static struct s5pv210_dvs_conf dvs_conf_workaround[] = {
+	[L0] = {
+		.arm_volt   = 1300000,
+		.int_volt   = 1200000,
+	},
+	[L1] = {
+		.arm_volt   = 1250000,
+		.int_volt   = 1200000,
+
+	},
+	[L2] = {
+		.arm_volt   = 1250000,
+		.int_volt   = 1200000,
+
+	},
+	[L3] = {
+		.arm_volt   = 1250000,
+		.int_volt   = 1200000,
+	},
+	[L4] = {
+		.arm_volt   = 1250000,
+		.int_volt   = 1200000,
+	},
+};
+static struct s5pv210_dvs_conf dvs_conf_default[] = {
+	[L0] = {
+		.arm_volt   = 1250000,
+		.int_volt   = 1100000,
+	},
+	[L1] = {
+		.arm_volt   = 1200000,
+		.int_volt   = 1100000,
+	},
+	[L2] = {
+		.arm_volt   = 1050000,
+		.int_volt   = 1100000,
+	},
+	[L3] = {
+		.arm_volt   = 950000,
+		.int_volt   = 1100000,
+	},
+	[L4] = {
+		.arm_volt   = 950000,
+		.int_volt   = 1000000,
+	},
+};
+static struct s5pv210_dvs_conf *dvs_conf = dvs_conf_default;
+
+static u32 clkdiv_val[5][11] = {
+	/*{ APLL, A2M, HCLK_MSYS, PCLK_MSYS,
+	 * HCLK_DSYS, PCLK_DSYS, HCLK_PSYS, PCLK_PSYS, ONEDRAM,
+	 * MFC, G3D }
+	 */
+	/* L0 : [1000/200/200/100][166/83][133/66][200/200] */
+	{0, 4, 4, 1, 3, 1, 4, 1, 3, 0, 0},
+	/* L1 : [800/200/200/100][166/83][133/66][200/200] */
+	{0, 3, 3, 1, 3, 1, 4, 1, 3, 0, 0},
+	/* L2 : [400/200/200/100][166/83][133/66][200/200] */
+	{1, 3, 1, 1, 3, 1, 4, 1, 3, 0, 0},
+	/* L3 : [200/200/200/100][166/83][133/66][200/200] */
+	{3, 3, 0, 1, 3, 1, 4, 1, 3, 0, 0},
+	/* L4 : [100/100/100/100][83/83][66/66][100/100] */
+	{7, 7, 0, 0, 7, 0, 9, 0, 7, 0, 0},
+};
+
+static struct s3c_freq clk_info[] = {
+	[L0] = {	/* L0: 1GHz */
+		.fclk       = 1000000,
+		.armclk     = 1000000,
+		.hclk_tns   = 0,
+		.hclk       = 133000,
+		.pclk       = 66000,
+		.hclk_msys  = 200000,
+		.pclk_msys  = 100000,
+		.hclk_dsys  = 166750,
+		.pclk_dsys  = 83375,
+	},
+	[L1] = {	/* L1: 800MHz */
+		.fclk       = 800000,
+		.armclk     = 800000,
+		.hclk_tns   = 0,
+		.hclk       = 133000,
+		.pclk       = 66000,
+		.hclk_msys  = 200000,
+		.pclk_msys  = 100000,
+		.hclk_dsys  = 166750,
+		.pclk_dsys  = 83375,
+	},
+	[L2] = {	/* L2: 400MHz */
+		.fclk       = 800000,
+		.armclk     = 400000,
+		.hclk_tns   = 0,
+		.hclk       = 133000,
+		.pclk       = 66000,
+		.hclk_msys  = 200000,
+		.pclk_msys  = 100000,
+		.hclk_dsys  = 166750,
+		.pclk_dsys  = 83375,
+	},
+	[L3] = {	/* L3: 200MHz */
+		.fclk       = 800000,
+		.armclk     = 200000,
+		.hclk_tns   = 0,
+		.hclk       = 133000,
+		.pclk       = 66000,
+		.hclk_msys  = 200000,
+		.pclk_msys  = 100000,
+		.hclk_dsys  = 166750,
+		.pclk_dsys  = 83375,
+	},
+	[L4] = {	/* L4: 100MHz */
+		.fclk       = 800000,
+		.armclk     = 100000,
+		.hclk_tns   = 0,
+		.hclk       = 66000,
+		.pclk       = 66000,
+		.hclk_msys  = 100000,
+		.pclk_msys  = 100000,
+		.hclk_dsys  = 83375,
+		.pclk_dsys  = 83375,
+	},
+};
+
+static int s5pv210_verify_speed(struct cpufreq_policy *policy)
+{
+
+	if (policy->cpu)
+		return -EINVAL;
+
+	return cpufreq_frequency_table_verify(policy, freq_table);
+}
+
+static unsigned int s5pv210_getspeed(unsigned int cpu)
+{
+	unsigned long rate;
+
+	if (cpu)
+		return 0;
+
+	rate = clk_get_rate(mpu_clk) / 1000;
+
+	return rate;
+}
+
+static void s5pv210_target_APLL2MPLL(unsigned int index,
+		unsigned int bus_speed_changing)
+{
+	unsigned int reg;
+
+	/*
+	 * 1. Temporarily change divider for MFC and G3D
+	 * SCLKA2M(200/1=200)->(200/4=50)MHz
+	 */
+	reg = __raw_readl(S5P_CLK_DIV2);
+	reg &= ~(S5P_CLKDIV2_G3D_MASK | S5P_CLKDIV2_MFC_MASK);
+	reg |= (0x3 << S5P_CLKDIV2_G3D_SHIFT) |
+		(0x3 << S5P_CLKDIV2_MFC_SHIFT);
+	if (s5pv210_workaround()) {
+		/*
+		 * Early version does NOT have G2D
+		 * Do Nothing about G2D.
+		 */
+	} else {
+		reg &= ~S5P_CLKDIV2_G2D_MASK;
+		reg |= (0x2 << S5P_CLKDIV2_G2D_SHIFT);
+	}
+
+	__raw_writel(reg, S5P_CLK_DIV2);
+
+	/* For MFC, G3D dividing */
+	do {
+		reg = __raw_readl(S5P_CLK_DIV_STAT0);
+	} while (reg & ((1 << 16) | (1 << 17)));
+
+	/*
+	 * 2. Change SCLKA2M(200MHz) to SCLKMPLL in MFC_MUX, G3D MUX
+	 * (100/4=50)->(667/4=166)MHz
+	 */
+	reg = __raw_readl(S5P_CLK_SRC2);
+	reg &= ~(S5P_CLKSRC2_G3D_MASK | S5P_CLKSRC2_MFC_MASK);
+	reg |= (0x1 << S5P_CLKSRC2_G3D_SHIFT) |
+		(0x1 << S5P_CLKSRC2_MFC_SHIFT);
+	if (s5pv210_workaround()) {
+		/*
+		 * Early version does NOT have G2D
+		 * Do Nothing about G2D.
+		 */
+	} else {
+		reg &= ~S5P_CLKSRC2_G2D_MASK;
+		reg |= (0x1 << S5P_CLKSRC2_G2D_SHIFT);
+	}
+	__raw_writel(reg, S5P_CLK_SRC2);
+
+	do {
+		reg = __raw_readl(S5P_CLK_MUX_STAT1);
+	} while (reg & ((1 << 7) | (1 << 3)));
+
+	/* 3. msys: SCLKAPLL -> SCLKMPLL */
+	reg = __raw_readl(S5P_CLK_SRC0);
+	reg &= ~(S5P_CLKSRC0_MUX200_MASK);
+	reg |= (0x1 << S5P_CLKSRC0_MUX200_SHIFT);
+	__raw_writel(reg, S5P_CLK_SRC0);
+
+	do {
+		reg = __raw_readl(S5P_CLK_MUX_STAT0);
+	} while (reg & (0x1 << 18));
+}
+
+static void s5pv210_target_MPLL2APLL(unsigned int index,
+		unsigned int bus_speed_changing)
+{
+	unsigned int reg;
+
+	/*
+	 * 7. Set Lock time = 30us*24MHz = 02cf (EVT1)
+	 * WORKAROUND: Lock time = 300us*24Mhz = 7200(0x1c20)
+	 * Normal:     Lock time = 30us*24Mhz = 0x2cf
+	 */
+	if (s5pv210_workaround())
+		__raw_writel(0x1c20, S5P_APLL_LOCK);
+	else
+		__raw_writel(0x2cf, S5P_APLL_LOCK);
+
+	/*
+	 * 8. Turn on APLL
+	 * 8-1. Set PMS values
+	 * 8-3. Wait until the PLL is locked
+	 */
+	if (index == L0)
+		/* APLL FOUT becomes 1000 Mhz */
+		__raw_writel(PLL45XX_APLL_VAL_1000, S5P_APLL_CON);
+	else
+		/* APLL FOUT becomes 800 Mhz */
+		__raw_writel(PLL45XX_APLL_VAL_800, S5P_APLL_CON);
+
+	do {
+		reg = __raw_readl(S5P_APLL_CON);
+	} while (!(reg & (0x1 << 29)));
+
+	/*
+	 * 9. Change source clock from SCLKMPLL(667MHz)
+	 * to SCLKA2M(200MHz) in MFC_MUX and G3D_MUX
+	 * (667/4=166)->(200/4=50)MHz
+	 */
+	reg = __raw_readl(S5P_CLK_SRC2);
+	reg &= ~(S5P_CLKSRC2_G3D_MASK | S5P_CLKSRC2_MFC_MASK);
+	reg |= (0 << S5P_CLKSRC2_G3D_SHIFT) | (0 << S5P_CLKSRC2_MFC_SHIFT);
+	if (s5pv210_workaround()) {
+		/*
+		 * Early version does NOT have G2D
+		 * Do Nothing about G2D.
+		 */
+	} else {
+		reg &= ~S5P_CLKSRC2_G2D_MASK;
+		reg |= 0x1 << S5P_CLKSRC2_G2D_SHIFT;
+	}
+	__raw_writel(reg, S5P_CLK_SRC2);
+
+	do {
+		reg = __raw_readl(S5P_CLK_MUX_STAT1);
+	} while (reg & ((1 << 7) | (1 << 3)));
+
+	/*
+	 * 10. Change divider for MFC and G3D
+	 * (200/4=50)->(200/1=200)MHz
+	 */
+	reg = __raw_readl(S5P_CLK_DIV2);
+	reg &= ~(S5P_CLKDIV2_G3D_MASK | S5P_CLKDIV2_MFC_MASK);
+	reg |= (clkdiv_val[index][10] << S5P_CLKDIV2_G3D_SHIFT) |
+		(clkdiv_val[index][9] << S5P_CLKDIV2_MFC_SHIFT);
+	if (s5pv210_workaround()) {
+		/*
+		 * Early version does NOT have G2D
+		 * Do Nothing about G2D.
+		 */
+	} else {
+		reg &= ~S5P_CLKDIV2_G2D_MASK;
+		reg |= 0x2 << S5P_CLKDIV2_G2D_SHIFT;
+	}
+	__raw_writel(reg, S5P_CLK_DIV2);
+
+	do {
+		reg = __raw_readl(S5P_CLK_DIV_STAT0);
+	} while (reg & ((1 << 16) | (1 << 17)));
+
+	/* 11. Change MPLL to APLL in MSYS_MUX */
+	reg = __raw_readl(S5P_CLK_SRC0);
+	reg &= ~(S5P_CLKSRC0_MUX200_MASK);
+	reg |= (0x0 << S5P_CLKSRC0_MUX200_SHIFT); /* SCLKMPLL -> SCLKAPLL   */
+	__raw_writel(reg, S5P_CLK_SRC0);
+
+	do {
+		reg = __raw_readl(S5P_CLK_MUX_STAT0);
+	} while (reg & (0x1 << 18));
+}
+
+#ifdef CONFIG_PM
+static int no_cpufreq_access;
+/*
+ * s5pv210_target: relation has an additional symantics other than
+ * the standard
+ * [0x30]:
+ *	1: disable further access to target until being re-enabled.
+ *	2: re-enable access to target */
+#endif
+static int s5pv210_target(struct cpufreq_policy *policy,
+		unsigned int target_freq,
+		unsigned int relation)
+{
+	static int initialized;
+	int ret = 0;
+	unsigned long arm_clk;
+	unsigned int index, reg, arm_volt, int_volt;
+	unsigned int pll_changing = 0;
+	unsigned int bus_speed_changing = 0;
+
+	cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, KERN_INFO,
+			"cpufreq: Entering for %dkHz\n", target_freq);
+#ifdef CONFIG_PM
+	if ((relation & ENABLE_FURTHER_CPUFREQ) &&
+			(relation & DISABLE_FURTHER_CPUFREQ)) {
+		/* Invalidate both if both marked */
+		relation &= ~ENABLE_FURTHER_CPUFREQ;
+		relation &= ~DISABLE_FURTHER_CPUFREQ;
+		pr_err("%s:%d denied marking \"FURTHER_CPUFREQ\""
+				" as both marked.\n",
+				__FILE__, __LINE__);
+	}
+	if (relation & ENABLE_FURTHER_CPUFREQ)
+		no_cpufreq_access = 0;
+	if (no_cpufreq_access == 1) {
+#ifdef CONFIG_PM_VERBOSE
+		pr_err("%s:%d denied access to %s as it is disabled"
+			       " temporarily\n", __FILE__, __LINE__, __func__);
+#endif
+		ret = -EINVAL;
+		goto out;
+	}
+	if (relation & DISABLE_FURTHER_CPUFREQ)
+		no_cpufreq_access = 1;
+	relation &= ~MASK_FURTHER_CPUFREQ;
+#endif
+
+	s3c_freqs.freqs.old = s5pv210_getspeed(0);
+
+	if (cpufreq_frequency_table_target(policy, freq_table,
+				target_freq, relation, &index)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	arm_clk = freq_table[index].frequency;
+
+	s3c_freqs.freqs.new = arm_clk;
+	s3c_freqs.freqs.cpu = 0;
+
+	/*
+	 * Run this function unconditionally until s3c_freqs.freqs.new
+	 * and s3c_freqs.freqs.old are both set by this function.
+	 */
+	if (s3c_freqs.freqs.new == s3c_freqs.freqs.old &&
+			initialized >= 2)
+		return 0;
+	else if (initialized < 2)
+		initialized++;
+
+	arm_volt = dvs_conf[index].arm_volt;
+	int_volt = dvs_conf[index].int_volt;
+
+	/* iNew clock information update */
+	memcpy(&s3c_freqs.new, &clk_info[index],
+			sizeof(struct s3c_freq));
+
+	if (s3c_freqs.freqs.new >= s3c_freqs.freqs.old) {
+		/* Voltage up code: increase ARM first */
+		if (!IS_ERR_OR_NULL(arm_regulator) &&
+				!IS_ERR_OR_NULL(internal_regulator)) {
+			regulator_set_voltage(arm_regulator,
+					arm_volt, arm_volt_max);
+			regulator_set_voltage(internal_regulator,
+					int_volt, int_volt_max);
+		}
+	}
+	cpufreq_notify_transition(&s3c_freqs.freqs, CPUFREQ_PRECHANGE);
+
+	if (s3c_freqs.new.fclk != s3c_freqs.old.fclk || initialized < 2)
+		pll_changing = 1;
+
+	if (s3c_freqs.new.hclk_msys != s3c_freqs.old.hclk_msys ||
+			initialized < 2)
+		bus_speed_changing = 1;
+
+	/*
+	 * If ONEDRAM(DMC0)'s clock is getting slower, DMC0's
+	 * refresh counter should decrease before slowing down
+	 * DMC0 clock. We assume that DMC0's source clock never
+	 * changes. This is a temporary setting for the transition.
+	 * Stable setting is done at the end of this function.
+	 */
+	reg = (__raw_readl(S5P_CLK_DIV6) & S5P_CLKDIV6_ONEDRAM_MASK)
+		>> S5P_CLKDIV6_ONEDRAM_SHIFT;
+	if (clkdiv_val[index][8] > reg) {
+		reg = backup_dmc0_reg * (reg + 1) / (clkdiv_val[index][8] + 1);
+		WARN_ON(reg > 0xFFFF);
+		reg &= 0xFFFF;
+		__raw_writel(reg, S5P_VA_DMC0 + 0x30);
+	}
+
+	/*
+	 * If hclk_msys (for DMC1) is getting slower, DMC1's
+	 * refresh counter should decrease before slowing down
+	 * hclk_msys in order to get rid of glitches in the
+	 * transition. This is temporary setting for the transition.
+	 * Stable setting is done at the end of this function.
+	 *
+	 * Besides, we need to consider the case when PLL speed changes,
+	 * where the DMC1's source clock hclk_msys is changed from ARMCLK
+	 * to MPLL temporarily. DMC1 needs to be ready for this
+	 * transition as well.
+	 */
+	if (s3c_freqs.new.hclk_msys < s3c_freqs.old.hclk_msys) {
+		/*
+		 * hclk_msys is up to 12bit. (200000)
+		 * reg is 16bit. so no overflow, yet.
+		 *
+		 * May need to use div64.h later with larger hclk_msys or
+		 * DMCx refresh counter. But, we have bugs in do_div and
+		 * that should be fixed before.
+		 */
+		reg = backup_dmc1_reg * s3c_freqs.new.hclk_msys;
+		reg /= clk_info[backup_freq_level].hclk_msys;
+
+		/*
+		 * When ARM_CLK is absed on APLL->MPLL,
+		 * hclk_msys becomes hclk_msys *= MPLL/APLL;
+		 *
+		 * Based on the worst case scenario, we use MPLL/APLL_MAX
+		 * assuming that MPLL clock speed does not change.
+		 *
+		 * Multiplied first in order to reduce rounding error.
+		 * because reg has 15b length, using 64b should be enough to
+		 * prevent overflow.
+		 */
+		if (pll_changing) {
+			reg *= mpll_freq;
+			reg /= apll_freq_max;
+		}
+		WARN_ON(reg > 0xFFFF);
+		__raw_writel(reg & 0xFFFF, S5P_VA_DMC1 + 0x30);
+	}
+
+	/*
+	 * APLL should be changed in this level
+	 * APLL -> MPLL(for stable transition) -> APLL
+	 * Some clock source's clock API  are not prepared. Do not use clock API
+	 * in below code.
+	 */
+	if (pll_changing)
+		s5pv210_target_APLL2MPLL(index, bus_speed_changing);
+
+	/* ARM MCS value changed */
+	if (index != L4) {
+		reg = __raw_readl(S5P_ARM_MCS_CON);
+		reg &= ~0x3;
+		reg |= 0x1;
+		__raw_writel(reg, S5P_ARM_MCS_CON);
+	}
+
+	reg = __raw_readl(S5P_CLK_DIV0);
+
+	reg &= ~(S5P_CLKDIV0_APLL_MASK | S5P_CLKDIV0_A2M_MASK
+			| S5P_CLKDIV0_HCLK200_MASK | S5P_CLKDIV0_PCLK100_MASK
+			| S5P_CLKDIV0_HCLK166_MASK | S5P_CLKDIV0_PCLK83_MASK
+			| S5P_CLKDIV0_HCLK133_MASK | S5P_CLKDIV0_PCLK66_MASK);
+
+	reg |= ((clkdiv_val[index][0]<<S5P_CLKDIV0_APLL_SHIFT)
+			| (clkdiv_val[index][1] << S5P_CLKDIV0_A2M_SHIFT)
+			| (clkdiv_val[index][2] << S5P_CLKDIV0_HCLK200_SHIFT)
+			| (clkdiv_val[index][3] << S5P_CLKDIV0_PCLK100_SHIFT)
+			| (clkdiv_val[index][4] << S5P_CLKDIV0_HCLK166_SHIFT)
+			| (clkdiv_val[index][5] << S5P_CLKDIV0_PCLK83_SHIFT)
+			| (clkdiv_val[index][6] << S5P_CLKDIV0_HCLK133_SHIFT)
+			| (clkdiv_val[index][7] << S5P_CLKDIV0_PCLK66_SHIFT));
+
+	__raw_writel(reg, S5P_CLK_DIV0);
+
+	do {
+		reg = __raw_readl(S5P_CLK_DIV_STAT0);
+	} while (reg & 0xff);
+
+	/* ARM MCS value changed */
+	if (index == L4) {
+		reg = __raw_readl(S5P_ARM_MCS_CON);
+		reg &= ~0x3;
+		reg |= 0x3;
+		__raw_writel(reg, S5P_ARM_MCS_CON);
+	}
+
+	if (pll_changing)
+		s5pv210_target_MPLL2APLL(index, bus_speed_changing);
+
+	/*
+	 * Adjust DMC0 refresh ratio according to the rate of DMC0
+	 * The DIV value of DMC0 clock changes and SRC value is not controlled.
+	 * We assume that no one changes SRC value of DMC0 clock, either.
+	 */
+	reg = __raw_readl(S5P_CLK_DIV6);
+	reg &= ~S5P_CLKDIV6_ONEDRAM_MASK;
+	reg |= (clkdiv_val[index][8] << S5P_CLKDIV6_ONEDRAM_SHIFT);
+	/* ONEDRAM(DMC0) Clock Divider Ratio: 7+1 for L4, 3+1 for Others */
+	__raw_writel(reg, S5P_CLK_DIV6);
+	do {
+		reg = __raw_readl(S5P_CLK_DIV_STAT1);
+	} while (reg & (1 << 15));
+
+	/*
+	 * If DMC0 clock gets slower (by orginal clock speed / n),
+	 * then, the refresh rate should decrease
+	 * (by original refresh count / n) (n: divider)
+	 */
+	reg = backup_dmc0_reg * (clkdiv_val[backup_freq_level][8] + 1)
+		/ (clkdiv_val[index][8] + 1);
+	__raw_writel(reg & 0xFFFF, S5P_VA_DMC0 + 0x30);
+
+	/*
+	 * Adjust DMC1 refresh ratio according to the rate of hclk_msys
+	 * (L0~L3: 200 <-> L4: 100)
+	 * If DMC1 clock gets slower (by original clock speed * n),
+	 * then, the refresh rate should decrease
+	 * (by original refresh count * n) (n : clock rate)
+	 */
+	reg = backup_dmc1_reg * clk_info[index].hclk_msys;
+	reg /= clk_info[backup_freq_level].hclk_msys;
+	__raw_writel(reg & 0xFFFF, S5P_VA_DMC1 + 0x30);
+
+	if (s3c_freqs.freqs.new < s3c_freqs.freqs.old) {
+		/* Voltage down: decrease INT first.*/
+		if (!IS_ERR_OR_NULL(arm_regulator) &&
+				!IS_ERR_OR_NULL(internal_regulator)) {
+			regulator_set_voltage(internal_regulator,
+					int_volt, int_volt_max);
+			regulator_set_voltage(arm_regulator,
+					arm_volt, arm_volt_max);
+		}
+	}
+	cpufreq_notify_transition(&s3c_freqs.freqs, CPUFREQ_POSTCHANGE);
+
+	memcpy(&s3c_freqs.old, &s3c_freqs.new, sizeof(struct s3c_freq));
+	cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, KERN_INFO,
+			"cpufreq: Performance changed[L%d]\n", index);
+	previous_arm_volt = dvs_conf[index].arm_volt;
+out:
+	return ret;
+}
+
+#ifdef CONFIG_PM
+static int previous_frequency;
+
+static int s5pv210_cpufreq_suspend(struct cpufreq_policy *policy,
+		pm_message_t pmsg)
+{
+	int ret = 0;
+	pr_info("cpufreq: Entering suspend.\n");
+
+	previous_frequency = cpufreq_get(0);
+	ret = __cpufreq_driver_target(cpufreq_cpu_get(0), SLEEP_FREQ,
+			DISABLE_FURTHER_CPUFREQ);
+	return ret;
+}
+
+static int s5pv210_cpufreq_resume(struct cpufreq_policy *policy)
+{
+	int ret = 0;
+	u32 rate;
+	int level = CPUFREQ_TABLE_END;
+	int i;
+
+	pr_info("cpufreq: Waking up from a suspend.\n");
+
+	__cpufreq_driver_target(cpufreq_cpu_get(0), previous_frequency,
+			ENABLE_FURTHER_CPUFREQ);
+
+	/* Clock information update with wakeup value */
+	rate = clk_get_rate(mpu_clk);
+
+	i = 0;
+	while (freq_table[i].frequency != CPUFREQ_TABLE_END) {
+		if (freq_table[i].frequency * 1000 == rate) {
+			level = freq_table[i].index;
+			break;
+		}
+		i++;
+	}
+
+	if (level == CPUFREQ_TABLE_END) { /* Not found */
+		pr_err("[%s:%d] clock speed does not match: "
+				"%d. Using L1 of 800MHz.\n",
+				__FILE__, __LINE__, rate);
+		level = L1;
+	}
+
+	memcpy(&s3c_freqs.old, &clk_info[level],
+			sizeof(struct s3c_freq));
+	previous_arm_volt = dvs_conf[level].arm_volt;
+	return ret;
+}
+#endif
+
+static int __init s5pv210_cpu_init(struct cpufreq_policy *policy)
+{
+	u32 rate ;
+	int i, level = CPUFREQ_TABLE_END;
+	struct clk *mpll_clk;
+
+	pr_info("S5PV210 CPUFREQ Initialising...\n");
+#ifdef CONFIG_PM
+	no_cpufreq_access = 0;
+#endif
+	mpu_clk = clk_get(NULL, "armclk");
+	if (IS_ERR(mpu_clk)) {
+		pr_err("S5PV210 CPUFREQ cannot get armclk\n");
+		return PTR_ERR(mpu_clk);
+	}
+
+	if (policy->cpu != 0) {
+		pr_err("S5PV210 CPUFREQ cannot get proper cpu(%d)\n",
+				policy->cpu);
+		return -EINVAL;
+	}
+	policy->cur = policy->min = policy->max = s5pv210_getspeed(0);
+
+	cpufreq_frequency_table_get_attr(freq_table, policy->cpu);
+
+	policy->cpuinfo.transition_latency = 40000;	/* 1us */
+
+	rate = clk_get_rate(mpu_clk);
+	i = 0;
+
+	while (freq_table[i].frequency != CPUFREQ_TABLE_END) {
+		if (freq_table[i].frequency * 1000 == rate) {
+			level = freq_table[i].index;
+			break;
+		}
+		i++;
+	}
+
+	if (level == CPUFREQ_TABLE_END) { /* Not found */
+		pr_err("[%s:%d] clock speed does not match: "
+				"%d. Using L1 of 800MHz.\n",
+				__FILE__, __LINE__, rate);
+		level = L1;
+	}
+
+	backup_dmc0_reg = __raw_readl(S5P_VA_DMC0 + 0x30) & 0xFFFF;
+	backup_dmc1_reg = __raw_readl(S5P_VA_DMC1 + 0x30) & 0xFFFF;
+	backup_freq_level = level;
+	mpll_clk = clk_get(NULL, "mout_mpll");
+	mpll_freq = clk_get_rate(mpll_clk) / 1000 / 1000; /* in MHz */
+	clk_put(mpll_clk);
+	i = 0;
+	do {
+		int index = freq_table[i].index;
+		if (apll_freq_max < clk_info[index].fclk)
+			apll_freq_max = clk_info[index].fclk;
+		i++;
+	} while (freq_table[i].frequency != CPUFREQ_TABLE_END);
+	apll_freq_max /= 1000; /* in MHz */
+
+	memcpy(&s3c_freqs.old, &clk_info[level],
+			sizeof(struct s3c_freq));
+	previous_arm_volt = dvs_conf[level].arm_volt;
+
+	return cpufreq_frequency_table_cpuinfo(policy, freq_table);
+}
+
+static struct cpufreq_driver s5pv210_driver = {
+	.flags		= CPUFREQ_STICKY,
+	.verify		= s5pv210_verify_speed,
+	.target		= s5pv210_target,
+	.get		= s5pv210_getspeed,
+	.init		= s5pv210_cpu_init,
+	.name		= "s5pv210",
+#ifdef CONFIG_PM
+	.suspend	= s5pv210_cpufreq_suspend,
+	.resume		= s5pv210_cpufreq_resume,
+#endif
+};
+
+static int __init s5pv210_cpufreq_init(void)
+{
+	if (s5pv210_workaround())
+		dvs_conf = dvs_conf_workaround;
+
+	arm_regulator = regulator_get_exclusive(NULL, "vddarm");
+	if (IS_ERR(arm_regulator)) {
+		pr_err("failed to get regulater resource vddarm\n");
+		goto error;
+	}
+	internal_regulator = regulator_get_exclusive(NULL, "vddint");
+	if (IS_ERR(internal_regulator)) {
+		pr_err("failed to get regulater resource vddint\n");
+		goto error;
+	}
+	goto finish;
+error:
+	pr_warn("Cannot get vddarm or vddint. CPUFREQ Will not"
+		       " change the voltage.\n");
+finish:
+	return cpufreq_register_driver(&s5pv210_driver);
+}
+
+late_initcall(s5pv210_cpufreq_init);
diff --git a/arch/arm/mach-s5pv210/include/mach/cpu-freq.h b/arch/arm/mach-s5pv210/include/mach/cpu-freq.h
new file mode 100644
index 0000000..e1a1c0c
--- /dev/null
+++ b/arch/arm/mach-s5pv210/include/mach/cpu-freq.h
@@ -0,0 +1,40 @@
+/* arch/arm/mach-s5pv210/include/mach/cpu-freq.h
+ *
+ * Copyright (c) 2010 Samsung Electronics
+ *
+ *       MyungJoo Ham <myungjoo.ham at samsung.com>
+ *
+ * S5PV210/S5PC110 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.
+*/
+
+#ifndef __ASM_ARCH_CPU_FREQ_H
+#define __ASM_ARCH_CPU_FREQ_H
+
+#include <linux/cpufreq.h>
+
+#define USE_FREQ_TABLE
+
+enum perf_level {
+	L0 = 0,
+	L1,
+	L2,
+	L3,
+	L4,
+};
+
+#ifdef CONFIG_PM
+#define SLEEP_FREQ      (800 * 1000) /* Use 800MHz when entering sleep */
+
+/* additional symantics for "relation" in cpufreq with pm */
+#define DISABLE_FURTHER_CPUFREQ         0x10
+#define ENABLE_FURTHER_CPUFREQ          0x20
+#define MASK_FURTHER_CPUFREQ            0x30
+/* With 0x00(NOCHANGE), it depends on the previous "further" status */
+
+#endif /* CONFIG_PM */
+
+#endif /* __ASM_ARCH_CPU_FREQ_H */
-- 
1.6.3.3




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