Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / devfreq / exynos / exynos4_bus.c
diff --git a/kernel/drivers/devfreq/exynos/exynos4_bus.c b/kernel/drivers/devfreq/exynos/exynos4_bus.c
new file mode 100644 (file)
index 0000000..da95092
--- /dev/null
@@ -0,0 +1,1055 @@
+/* drivers/devfreq/exynos4210_memorybus.c
+ *
+ * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+ *             http://www.samsung.com/
+ *     MyungJoo Ham <myungjoo.ham@samsung.com>
+ *
+ * EXYNOS4 - Memory/Bus clock frequency scaling support in DEVFREQ framework
+ *     This version supports EXYNOS4210 only. This changes bus frequencies
+ *     and vddint voltages. Exynos4412/4212 should be able to be supported
+ *     with minor modifications.
+ *
+ * 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/io.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/suspend.h>
+#include <linux/pm_opp.h>
+#include <linux/devfreq.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/module.h>
+
+#include <mach/map.h>
+
+#include "exynos_ppmu.h"
+#include "exynos4_bus.h"
+
+#define MAX_SAFEVOLT   1200000 /* 1.2V */
+
+enum exynos4_busf_type {
+       TYPE_BUSF_EXYNOS4210,
+       TYPE_BUSF_EXYNOS4x12,
+};
+
+/* Assume that the bus is saturated if the utilization is 40% */
+#define BUS_SATURATION_RATIO   40
+
+enum busclk_level_idx {
+       LV_0 = 0,
+       LV_1,
+       LV_2,
+       LV_3,
+       LV_4,
+       _LV_END
+};
+
+enum exynos_ppmu_idx {
+       PPMU_DMC0,
+       PPMU_DMC1,
+       PPMU_END,
+};
+
+#define EX4210_LV_MAX  LV_2
+#define EX4x12_LV_MAX  LV_4
+#define EX4210_LV_NUM  (LV_2 + 1)
+#define EX4x12_LV_NUM  (LV_4 + 1)
+
+/**
+ * struct busfreq_opp_info - opp information for bus
+ * @rate:      Frequency in hertz
+ * @volt:      Voltage in microvolts corresponding to this OPP
+ */
+struct busfreq_opp_info {
+       unsigned long rate;
+       unsigned long volt;
+};
+
+struct busfreq_data {
+       enum exynos4_busf_type type;
+       struct device *dev;
+       struct devfreq *devfreq;
+       bool disabled;
+       struct regulator *vdd_int;
+       struct regulator *vdd_mif; /* Exynos4412/4212 only */
+       struct busfreq_opp_info curr_oppinfo;
+       struct busfreq_ppmu_data ppmu_data;
+
+       struct notifier_block pm_notifier;
+       struct mutex lock;
+
+       /* Dividers calculated at boot/probe-time */
+       unsigned int dmc_divtable[_LV_END]; /* DMC0 */
+       unsigned int top_divtable[_LV_END];
+};
+
+/* 4210 controls clock of mif and voltage of int */
+static struct bus_opp_table exynos4210_busclk_table[] = {
+       {LV_0, 400000, 1150000},
+       {LV_1, 267000, 1050000},
+       {LV_2, 133000, 1025000},
+       {0, 0, 0},
+};
+
+/*
+ * MIF is the main control knob clock for Exynos4x12 MIF/INT
+ * clock and voltage of both mif/int are controlled.
+ */
+static struct bus_opp_table exynos4x12_mifclk_table[] = {
+       {LV_0, 400000, 1100000},
+       {LV_1, 267000, 1000000},
+       {LV_2, 160000, 950000},
+       {LV_3, 133000, 950000},
+       {LV_4, 100000, 950000},
+       {0, 0, 0},
+};
+
+/*
+ * INT is not the control knob of 4x12. LV_x is not meant to represent
+ * the current performance. (MIF does)
+ */
+static struct bus_opp_table exynos4x12_intclk_table[] = {
+       {LV_0, 200000, 1000000},
+       {LV_1, 160000, 950000},
+       {LV_2, 133000, 925000},
+       {LV_3, 100000, 900000},
+       {0, 0, 0},
+};
+
+/* TODO: asv volt definitions are "__initdata"? */
+/* Some chips have different operating voltages */
+static unsigned int exynos4210_asv_volt[][EX4210_LV_NUM] = {
+       {1150000, 1050000, 1050000},
+       {1125000, 1025000, 1025000},
+       {1100000, 1000000, 1000000},
+       {1075000, 975000, 975000},
+       {1050000, 950000, 950000},
+};
+
+static unsigned int exynos4x12_mif_step_50[][EX4x12_LV_NUM] = {
+       /* 400      267     160     133     100 */
+       {1050000, 950000, 900000, 900000, 900000}, /* ASV0 */
+       {1050000, 950000, 900000, 900000, 900000}, /* ASV1 */
+       {1050000, 950000, 900000, 900000, 900000}, /* ASV2 */
+       {1050000, 900000, 900000, 900000, 900000}, /* ASV3 */
+       {1050000, 900000, 900000, 900000, 850000}, /* ASV4 */
+       {1050000, 900000, 900000, 850000, 850000}, /* ASV5 */
+       {1050000, 900000, 850000, 850000, 850000}, /* ASV6 */
+       {1050000, 900000, 850000, 850000, 850000}, /* ASV7 */
+       {1050000, 900000, 850000, 850000, 850000}, /* ASV8 */
+};
+
+static unsigned int exynos4x12_int_volt[][EX4x12_LV_NUM] = {
+       /* 200    160      133     100 */
+       {1000000, 950000, 925000, 900000}, /* ASV0 */
+       {975000,  925000, 925000, 900000}, /* ASV1 */
+       {950000,  925000, 900000, 875000}, /* ASV2 */
+       {950000,  900000, 900000, 875000}, /* ASV3 */
+       {925000,  875000, 875000, 875000}, /* ASV4 */
+       {900000,  850000, 850000, 850000}, /* ASV5 */
+       {900000,  850000, 850000, 850000}, /* ASV6 */
+       {900000,  850000, 850000, 850000}, /* ASV7 */
+       {900000,  850000, 850000, 850000}, /* ASV8 */
+};
+
+/*** Clock Divider Data for Exynos4210 ***/
+static unsigned int exynos4210_clkdiv_dmc0[][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: 266.7MHz */
+       { 4, 1, 1, 2, 1, 1, 3, 1 },
+       /* DMC L2: 133MHz */
+       { 5, 1, 1, 5, 1, 1, 3, 1 },
+};
+static unsigned int exynos4210_clkdiv_top[][5] = {
+       /*
+        * Clock divider value for following
+        * { DIVACLK200, DIVACLK100, DIVACLK160, DIVACLK133, DIVONENAND }
+        */
+       /* ACLK200 L0: 200MHz */
+       { 3, 7, 4, 5, 1 },
+       /* ACLK200 L1: 160MHz */
+       { 4, 7, 5, 6, 1 },
+       /* ACLK200 L2: 133MHz */
+       { 5, 7, 7, 7, 1 },
+};
+static unsigned int exynos4210_clkdiv_lr_bus[][2] = {
+       /*
+        * Clock divider value for following
+        * { DIVGDL/R, DIVGPL/R }
+        */
+       /* ACLK_GDL/R L1: 200MHz */
+       { 3, 1 },
+       /* ACLK_GDL/R L2: 160MHz */
+       { 4, 1 },
+       /* ACLK_GDL/R L3: 133MHz */
+       { 5, 1 },
+};
+
+/*** Clock Divider Data for Exynos4212/4412 ***/
+static unsigned int exynos4x12_clkdiv_dmc0[][6] = {
+       /*
+        * Clock divider value for following
+        * { DIVACP, DIVACP_PCLK, DIVDPHY, DIVDMC, DIVDMCD
+        *              DIVDMCP}
+        */
+
+       /* DMC L0: 400MHz */
+       {3, 1, 1, 1, 1, 1},
+       /* DMC L1: 266.7MHz */
+       {4, 1, 1, 2, 1, 1},
+       /* DMC L2: 160MHz */
+       {5, 1, 1, 4, 1, 1},
+       /* DMC L3: 133MHz */
+       {5, 1, 1, 5, 1, 1},
+       /* DMC L4: 100MHz */
+       {7, 1, 1, 7, 1, 1},
+};
+static unsigned int exynos4x12_clkdiv_dmc1[][6] = {
+       /*
+        * Clock divider value for following
+        * { G2DACP, DIVC2C, DIVC2C_ACLK }
+        */
+
+       /* DMC L0: 400MHz */
+       {3, 1, 1},
+       /* DMC L1: 266.7MHz */
+       {4, 2, 1},
+       /* DMC L2: 160MHz */
+       {5, 4, 1},
+       /* DMC L3: 133MHz */
+       {5, 5, 1},
+       /* DMC L4: 100MHz */
+       {7, 7, 1},
+};
+static unsigned int exynos4x12_clkdiv_top[][5] = {
+       /*
+        * Clock divider value for following
+        * { DIVACLK266_GPS, DIVACLK100, DIVACLK160,
+               DIVACLK133, DIVONENAND }
+        */
+
+       /* ACLK_GDL/R L0: 200MHz */
+       {2, 7, 4, 5, 1},
+       /* ACLK_GDL/R L1: 200MHz */
+       {2, 7, 4, 5, 1},
+       /* ACLK_GDL/R L2: 160MHz */
+       {4, 7, 5, 7, 1},
+       /* ACLK_GDL/R L3: 133MHz */
+       {4, 7, 5, 7, 1},
+       /* ACLK_GDL/R L4: 100MHz */
+       {7, 7, 7, 7, 1},
+};
+static unsigned int exynos4x12_clkdiv_lr_bus[][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: 160MHz */
+       {4, 1},
+       /* ACLK_GDL/R L3: 133MHz */
+       {5, 1},
+       /* ACLK_GDL/R L4: 100MHz */
+       {7, 1},
+};
+static unsigned int exynos4x12_clkdiv_sclkip[][3] = {
+       /*
+        * Clock divider value for following
+        * { DIVMFC, DIVJPEG, DIVFIMC0~3}
+        */
+
+       /* SCLK_MFC: 200MHz */
+       {3, 3, 4},
+       /* SCLK_MFC: 200MHz */
+       {3, 3, 4},
+       /* SCLK_MFC: 160MHz */
+       {4, 4, 5},
+       /* SCLK_MFC: 133MHz */
+       {5, 5, 5},
+       /* SCLK_MFC: 100MHz */
+       {7, 7, 7},
+};
+
+
+static int exynos4210_set_busclk(struct busfreq_data *data,
+                                struct busfreq_opp_info *oppi)
+{
+       unsigned int index;
+       unsigned int tmp;
+
+       for (index = LV_0; index < EX4210_LV_NUM; index++)
+               if (oppi->rate == exynos4210_busclk_table[index].clk)
+                       break;
+
+       if (index == EX4210_LV_NUM)
+               return -EINVAL;
+
+       /* Change Divider - DMC0 */
+       tmp = data->dmc_divtable[index];
+
+       __raw_writel(tmp, EXYNOS4_CLKDIV_DMC0);
+
+       do {
+               tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_DMC0);
+       } while (tmp & 0x11111111);
+
+       /* Change Divider - TOP */
+       tmp = data->top_divtable[index];
+
+       __raw_writel(tmp, EXYNOS4_CLKDIV_TOP);
+
+       do {
+               tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_TOP);
+       } while (tmp & 0x11111);
+
+       /* Change Divider - LEFTBUS */
+       tmp = __raw_readl(EXYNOS4_CLKDIV_LEFTBUS);
+
+       tmp &= ~(EXYNOS4_CLKDIV_BUS_GDLR_MASK | EXYNOS4_CLKDIV_BUS_GPLR_MASK);
+
+       tmp |= ((exynos4210_clkdiv_lr_bus[index][0] <<
+                               EXYNOS4_CLKDIV_BUS_GDLR_SHIFT) |
+               (exynos4210_clkdiv_lr_bus[index][1] <<
+                               EXYNOS4_CLKDIV_BUS_GPLR_SHIFT));
+
+       __raw_writel(tmp, EXYNOS4_CLKDIV_LEFTBUS);
+
+       do {
+               tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_LEFTBUS);
+       } while (tmp & 0x11);
+
+       /* Change Divider - RIGHTBUS */
+       tmp = __raw_readl(EXYNOS4_CLKDIV_RIGHTBUS);
+
+       tmp &= ~(EXYNOS4_CLKDIV_BUS_GDLR_MASK | EXYNOS4_CLKDIV_BUS_GPLR_MASK);
+
+       tmp |= ((exynos4210_clkdiv_lr_bus[index][0] <<
+                               EXYNOS4_CLKDIV_BUS_GDLR_SHIFT) |
+               (exynos4210_clkdiv_lr_bus[index][1] <<
+                               EXYNOS4_CLKDIV_BUS_GPLR_SHIFT));
+
+       __raw_writel(tmp, EXYNOS4_CLKDIV_RIGHTBUS);
+
+       do {
+               tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_RIGHTBUS);
+       } while (tmp & 0x11);
+
+       return 0;
+}
+
+static int exynos4x12_set_busclk(struct busfreq_data *data,
+                                struct busfreq_opp_info *oppi)
+{
+       unsigned int index;
+       unsigned int tmp;
+
+       for (index = LV_0; index < EX4x12_LV_NUM; index++)
+               if (oppi->rate == exynos4x12_mifclk_table[index].clk)
+                       break;
+
+       if (index == EX4x12_LV_NUM)
+               return -EINVAL;
+
+       /* Change Divider - DMC0 */
+       tmp = data->dmc_divtable[index];
+
+       __raw_writel(tmp, EXYNOS4_CLKDIV_DMC0);
+
+       do {
+               tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_DMC0);
+       } while (tmp & 0x11111111);
+
+       /* Change Divider - DMC1 */
+       tmp = __raw_readl(EXYNOS4_CLKDIV_DMC1);
+
+       tmp &= ~(EXYNOS4_CLKDIV_DMC1_G2D_ACP_MASK |
+               EXYNOS4_CLKDIV_DMC1_C2C_MASK |
+               EXYNOS4_CLKDIV_DMC1_C2CACLK_MASK);
+
+       tmp |= ((exynos4x12_clkdiv_dmc1[index][0] <<
+                               EXYNOS4_CLKDIV_DMC1_G2D_ACP_SHIFT) |
+               (exynos4x12_clkdiv_dmc1[index][1] <<
+                               EXYNOS4_CLKDIV_DMC1_C2C_SHIFT) |
+               (exynos4x12_clkdiv_dmc1[index][2] <<
+                               EXYNOS4_CLKDIV_DMC1_C2CACLK_SHIFT));
+
+       __raw_writel(tmp, EXYNOS4_CLKDIV_DMC1);
+
+       do {
+               tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_DMC1);
+       } while (tmp & 0x111111);
+
+       /* Change Divider - TOP */
+       tmp = __raw_readl(EXYNOS4_CLKDIV_TOP);
+
+       tmp &= ~(EXYNOS4_CLKDIV_TOP_ACLK266_GPS_MASK |
+               EXYNOS4_CLKDIV_TOP_ACLK100_MASK |
+               EXYNOS4_CLKDIV_TOP_ACLK160_MASK |
+               EXYNOS4_CLKDIV_TOP_ACLK133_MASK |
+               EXYNOS4_CLKDIV_TOP_ONENAND_MASK);
+
+       tmp |= ((exynos4x12_clkdiv_top[index][0] <<
+                               EXYNOS4_CLKDIV_TOP_ACLK266_GPS_SHIFT) |
+               (exynos4x12_clkdiv_top[index][1] <<
+                               EXYNOS4_CLKDIV_TOP_ACLK100_SHIFT) |
+               (exynos4x12_clkdiv_top[index][2] <<
+                               EXYNOS4_CLKDIV_TOP_ACLK160_SHIFT) |
+               (exynos4x12_clkdiv_top[index][3] <<
+                               EXYNOS4_CLKDIV_TOP_ACLK133_SHIFT) |
+               (exynos4x12_clkdiv_top[index][4] <<
+                               EXYNOS4_CLKDIV_TOP_ONENAND_SHIFT));
+
+       __raw_writel(tmp, EXYNOS4_CLKDIV_TOP);
+
+       do {
+               tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_TOP);
+       } while (tmp & 0x11111);
+
+       /* Change Divider - LEFTBUS */
+       tmp = __raw_readl(EXYNOS4_CLKDIV_LEFTBUS);
+
+       tmp &= ~(EXYNOS4_CLKDIV_BUS_GDLR_MASK | EXYNOS4_CLKDIV_BUS_GPLR_MASK);
+
+       tmp |= ((exynos4x12_clkdiv_lr_bus[index][0] <<
+                               EXYNOS4_CLKDIV_BUS_GDLR_SHIFT) |
+               (exynos4x12_clkdiv_lr_bus[index][1] <<
+                               EXYNOS4_CLKDIV_BUS_GPLR_SHIFT));
+
+       __raw_writel(tmp, EXYNOS4_CLKDIV_LEFTBUS);
+
+       do {
+               tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_LEFTBUS);
+       } while (tmp & 0x11);
+
+       /* Change Divider - RIGHTBUS */
+       tmp = __raw_readl(EXYNOS4_CLKDIV_RIGHTBUS);
+
+       tmp &= ~(EXYNOS4_CLKDIV_BUS_GDLR_MASK | EXYNOS4_CLKDIV_BUS_GPLR_MASK);
+
+       tmp |= ((exynos4x12_clkdiv_lr_bus[index][0] <<
+                               EXYNOS4_CLKDIV_BUS_GDLR_SHIFT) |
+               (exynos4x12_clkdiv_lr_bus[index][1] <<
+                               EXYNOS4_CLKDIV_BUS_GPLR_SHIFT));
+
+       __raw_writel(tmp, EXYNOS4_CLKDIV_RIGHTBUS);
+
+       do {
+               tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_RIGHTBUS);
+       } while (tmp & 0x11);
+
+       /* Change Divider - MFC */
+       tmp = __raw_readl(EXYNOS4_CLKDIV_MFC);
+
+       tmp &= ~(EXYNOS4_CLKDIV_MFC_MASK);
+
+       tmp |= ((exynos4x12_clkdiv_sclkip[index][0] <<
+                               EXYNOS4_CLKDIV_MFC_SHIFT));
+
+       __raw_writel(tmp, EXYNOS4_CLKDIV_MFC);
+
+       do {
+               tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_MFC);
+       } while (tmp & 0x1);
+
+       /* Change Divider - JPEG */
+       tmp = __raw_readl(EXYNOS4_CLKDIV_CAM1);
+
+       tmp &= ~(EXYNOS4_CLKDIV_CAM1_JPEG_MASK);
+
+       tmp |= ((exynos4x12_clkdiv_sclkip[index][1] <<
+                               EXYNOS4_CLKDIV_CAM1_JPEG_SHIFT));
+
+       __raw_writel(tmp, EXYNOS4_CLKDIV_CAM1);
+
+       do {
+               tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_CAM1);
+       } while (tmp & 0x1);
+
+       /* Change Divider - FIMC0~3 */
+       tmp = __raw_readl(EXYNOS4_CLKDIV_CAM);
+
+       tmp &= ~(EXYNOS4_CLKDIV_CAM_FIMC0_MASK | EXYNOS4_CLKDIV_CAM_FIMC1_MASK |
+               EXYNOS4_CLKDIV_CAM_FIMC2_MASK | EXYNOS4_CLKDIV_CAM_FIMC3_MASK);
+
+       tmp |= ((exynos4x12_clkdiv_sclkip[index][2] <<
+                               EXYNOS4_CLKDIV_CAM_FIMC0_SHIFT) |
+               (exynos4x12_clkdiv_sclkip[index][2] <<
+                               EXYNOS4_CLKDIV_CAM_FIMC1_SHIFT) |
+               (exynos4x12_clkdiv_sclkip[index][2] <<
+                               EXYNOS4_CLKDIV_CAM_FIMC2_SHIFT) |
+               (exynos4x12_clkdiv_sclkip[index][2] <<
+                               EXYNOS4_CLKDIV_CAM_FIMC3_SHIFT));
+
+       __raw_writel(tmp, EXYNOS4_CLKDIV_CAM);
+
+       do {
+               tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_CAM1);
+       } while (tmp & 0x1111);
+
+       return 0;
+}
+
+static int exynos4x12_get_intspec(unsigned long mifclk)
+{
+       int i = 0;
+
+       while (exynos4x12_intclk_table[i].clk) {
+               if (exynos4x12_intclk_table[i].clk <= mifclk)
+                       return i;
+               i++;
+       }
+
+       return -EINVAL;
+}
+
+static int exynos4_bus_setvolt(struct busfreq_data *data,
+                              struct busfreq_opp_info *oppi,
+                              struct busfreq_opp_info *oldoppi)
+{
+       int err = 0, tmp;
+       unsigned long volt = oppi->volt;
+
+       switch (data->type) {
+       case TYPE_BUSF_EXYNOS4210:
+               /* OPP represents DMC clock + INT voltage */
+               err = regulator_set_voltage(data->vdd_int, volt,
+                                           MAX_SAFEVOLT);
+               break;
+       case TYPE_BUSF_EXYNOS4x12:
+               /* OPP represents MIF clock + MIF voltage */
+               err = regulator_set_voltage(data->vdd_mif, volt,
+                                           MAX_SAFEVOLT);
+               if (err)
+                       break;
+
+               tmp = exynos4x12_get_intspec(oppi->rate);
+               if (tmp < 0) {
+                       err = tmp;
+                       regulator_set_voltage(data->vdd_mif,
+                                             oldoppi->volt,
+                                             MAX_SAFEVOLT);
+                       break;
+               }
+               err = regulator_set_voltage(data->vdd_int,
+                                           exynos4x12_intclk_table[tmp].volt,
+                                           MAX_SAFEVOLT);
+               /*  Try to recover */
+               if (err)
+                       regulator_set_voltage(data->vdd_mif,
+                                             oldoppi->volt,
+                                             MAX_SAFEVOLT);
+               break;
+       default:
+               err = -EINVAL;
+       }
+
+       return err;
+}
+
+static int exynos4_bus_target(struct device *dev, unsigned long *_freq,
+                             u32 flags)
+{
+       int err = 0;
+       struct platform_device *pdev = container_of(dev, struct platform_device,
+                                                   dev);
+       struct busfreq_data *data = platform_get_drvdata(pdev);
+       struct dev_pm_opp *opp;
+       unsigned long freq;
+       unsigned long old_freq = data->curr_oppinfo.rate;
+       struct busfreq_opp_info new_oppinfo;
+
+       rcu_read_lock();
+       opp = devfreq_recommended_opp(dev, _freq, flags);
+       if (IS_ERR(opp)) {
+               rcu_read_unlock();
+               return PTR_ERR(opp);
+       }
+       new_oppinfo.rate = dev_pm_opp_get_freq(opp);
+       new_oppinfo.volt = dev_pm_opp_get_voltage(opp);
+       rcu_read_unlock();
+       freq = new_oppinfo.rate;
+
+       if (old_freq == freq)
+               return 0;
+
+       dev_dbg(dev, "targeting %lukHz %luuV\n", freq, new_oppinfo.volt);
+
+       mutex_lock(&data->lock);
+
+       if (data->disabled)
+               goto out;
+
+       if (old_freq < freq)
+               err = exynos4_bus_setvolt(data, &new_oppinfo,
+                                         &data->curr_oppinfo);
+       if (err)
+               goto out;
+
+       if (old_freq != freq) {
+               switch (data->type) {
+               case TYPE_BUSF_EXYNOS4210:
+                       err = exynos4210_set_busclk(data, &new_oppinfo);
+                       break;
+               case TYPE_BUSF_EXYNOS4x12:
+                       err = exynos4x12_set_busclk(data, &new_oppinfo);
+                       break;
+               default:
+                       err = -EINVAL;
+               }
+       }
+       if (err)
+               goto out;
+
+       if (old_freq > freq)
+               err = exynos4_bus_setvolt(data, &new_oppinfo,
+                                         &data->curr_oppinfo);
+       if (err)
+               goto out;
+
+       data->curr_oppinfo = new_oppinfo;
+out:
+       mutex_unlock(&data->lock);
+       return err;
+}
+
+static int exynos4_bus_get_dev_status(struct device *dev,
+                                     struct devfreq_dev_status *stat)
+{
+       struct busfreq_data *data = dev_get_drvdata(dev);
+       struct busfreq_ppmu_data *ppmu_data = &data->ppmu_data;
+       int busier;
+
+       exynos_read_ppmu(ppmu_data);
+       busier = exynos_get_busier_ppmu(ppmu_data);
+       stat->current_frequency = data->curr_oppinfo.rate;
+
+       /* Number of cycles spent on memory access */
+       stat->busy_time = ppmu_data->ppmu[busier].count[PPMU_PMNCNT3];
+       stat->busy_time *= 100 / BUS_SATURATION_RATIO;
+       stat->total_time = ppmu_data->ppmu[busier].ccnt;
+
+       /* If the counters have overflown, retry */
+       if (ppmu_data->ppmu[busier].ccnt_overflow ||
+           ppmu_data->ppmu[busier].count_overflow[0])
+               return -EAGAIN;
+
+       return 0;
+}
+
+static struct devfreq_dev_profile exynos4_devfreq_profile = {
+       .initial_freq   = 400000,
+       .polling_ms     = 50,
+       .target         = exynos4_bus_target,
+       .get_dev_status = exynos4_bus_get_dev_status,
+};
+
+static int exynos4210_init_tables(struct busfreq_data *data)
+{
+       u32 tmp;
+       int mgrp;
+       int i, err = 0;
+
+       tmp = __raw_readl(EXYNOS4_CLKDIV_DMC0);
+       for (i = LV_0; i < EX4210_LV_NUM; i++) {
+               tmp &= ~(EXYNOS4_CLKDIV_DMC0_ACP_MASK |
+                       EXYNOS4_CLKDIV_DMC0_ACPPCLK_MASK |
+                       EXYNOS4_CLKDIV_DMC0_DPHY_MASK |
+                       EXYNOS4_CLKDIV_DMC0_DMC_MASK |
+                       EXYNOS4_CLKDIV_DMC0_DMCD_MASK |
+                       EXYNOS4_CLKDIV_DMC0_DMCP_MASK |
+                       EXYNOS4_CLKDIV_DMC0_COPY2_MASK |
+                       EXYNOS4_CLKDIV_DMC0_CORETI_MASK);
+
+               tmp |= ((exynos4210_clkdiv_dmc0[i][0] <<
+                                       EXYNOS4_CLKDIV_DMC0_ACP_SHIFT) |
+                       (exynos4210_clkdiv_dmc0[i][1] <<
+                                       EXYNOS4_CLKDIV_DMC0_ACPPCLK_SHIFT) |
+                       (exynos4210_clkdiv_dmc0[i][2] <<
+                                       EXYNOS4_CLKDIV_DMC0_DPHY_SHIFT) |
+                       (exynos4210_clkdiv_dmc0[i][3] <<
+                                       EXYNOS4_CLKDIV_DMC0_DMC_SHIFT) |
+                       (exynos4210_clkdiv_dmc0[i][4] <<
+                                       EXYNOS4_CLKDIV_DMC0_DMCD_SHIFT) |
+                       (exynos4210_clkdiv_dmc0[i][5] <<
+                                       EXYNOS4_CLKDIV_DMC0_DMCP_SHIFT) |
+                       (exynos4210_clkdiv_dmc0[i][6] <<
+                                       EXYNOS4_CLKDIV_DMC0_COPY2_SHIFT) |
+                       (exynos4210_clkdiv_dmc0[i][7] <<
+                                       EXYNOS4_CLKDIV_DMC0_CORETI_SHIFT));
+
+               data->dmc_divtable[i] = tmp;
+       }
+
+       tmp = __raw_readl(EXYNOS4_CLKDIV_TOP);
+       for (i = LV_0; i <  EX4210_LV_NUM; i++) {
+               tmp &= ~(EXYNOS4_CLKDIV_TOP_ACLK200_MASK |
+                       EXYNOS4_CLKDIV_TOP_ACLK100_MASK |
+                       EXYNOS4_CLKDIV_TOP_ACLK160_MASK |
+                       EXYNOS4_CLKDIV_TOP_ACLK133_MASK |
+                       EXYNOS4_CLKDIV_TOP_ONENAND_MASK);
+
+               tmp |= ((exynos4210_clkdiv_top[i][0] <<
+                                       EXYNOS4_CLKDIV_TOP_ACLK200_SHIFT) |
+                       (exynos4210_clkdiv_top[i][1] <<
+                                       EXYNOS4_CLKDIV_TOP_ACLK100_SHIFT) |
+                       (exynos4210_clkdiv_top[i][2] <<
+                                       EXYNOS4_CLKDIV_TOP_ACLK160_SHIFT) |
+                       (exynos4210_clkdiv_top[i][3] <<
+                                       EXYNOS4_CLKDIV_TOP_ACLK133_SHIFT) |
+                       (exynos4210_clkdiv_top[i][4] <<
+                                       EXYNOS4_CLKDIV_TOP_ONENAND_SHIFT));
+
+               data->top_divtable[i] = tmp;
+       }
+
+       /*
+        * TODO: init tmp based on busfreq_data
+        * (device-tree or platform-data)
+        */
+       tmp = 0; /* Max voltages for the reliability of the unknown */
+
+       pr_debug("ASV Group of Exynos4 is %d\n", tmp);
+       /* Use merged grouping for voltage */
+       switch (tmp) {
+       case 0:
+               mgrp = 0;
+               break;
+       case 1:
+       case 2:
+               mgrp = 1;
+               break;
+       case 3:
+       case 4:
+               mgrp = 2;
+               break;
+       case 5:
+       case 6:
+               mgrp = 3;
+               break;
+       case 7:
+               mgrp = 4;
+               break;
+       default:
+               pr_warn("Unknown ASV Group. Use max voltage.\n");
+               mgrp = 0;
+       }
+
+       for (i = LV_0; i < EX4210_LV_NUM; i++)
+               exynos4210_busclk_table[i].volt = exynos4210_asv_volt[mgrp][i];
+
+       for (i = LV_0; i < EX4210_LV_NUM; i++) {
+               err = dev_pm_opp_add(data->dev, exynos4210_busclk_table[i].clk,
+                             exynos4210_busclk_table[i].volt);
+               if (err) {
+                       dev_err(data->dev, "Cannot add opp entries.\n");
+                       return err;
+               }
+       }
+
+
+       return 0;
+}
+
+static int exynos4x12_init_tables(struct busfreq_data *data)
+{
+       unsigned int i;
+       unsigned int tmp;
+       int ret;
+
+       /* Enable pause function for DREX2 DVFS */
+       tmp = __raw_readl(EXYNOS4_DMC_PAUSE_CTRL);
+       tmp |= EXYNOS4_DMC_PAUSE_ENABLE;
+       __raw_writel(tmp, EXYNOS4_DMC_PAUSE_CTRL);
+
+       tmp = __raw_readl(EXYNOS4_CLKDIV_DMC0);
+
+       for (i = 0; i <  EX4x12_LV_NUM; i++) {
+               tmp &= ~(EXYNOS4_CLKDIV_DMC0_ACP_MASK |
+                       EXYNOS4_CLKDIV_DMC0_ACPPCLK_MASK |
+                       EXYNOS4_CLKDIV_DMC0_DPHY_MASK |
+                       EXYNOS4_CLKDIV_DMC0_DMC_MASK |
+                       EXYNOS4_CLKDIV_DMC0_DMCD_MASK |
+                       EXYNOS4_CLKDIV_DMC0_DMCP_MASK);
+
+               tmp |= ((exynos4x12_clkdiv_dmc0[i][0] <<
+                                       EXYNOS4_CLKDIV_DMC0_ACP_SHIFT) |
+                       (exynos4x12_clkdiv_dmc0[i][1] <<
+                                       EXYNOS4_CLKDIV_DMC0_ACPPCLK_SHIFT) |
+                       (exynos4x12_clkdiv_dmc0[i][2] <<
+                                       EXYNOS4_CLKDIV_DMC0_DPHY_SHIFT) |
+                       (exynos4x12_clkdiv_dmc0[i][3] <<
+                                       EXYNOS4_CLKDIV_DMC0_DMC_SHIFT) |
+                       (exynos4x12_clkdiv_dmc0[i][4] <<
+                                       EXYNOS4_CLKDIV_DMC0_DMCD_SHIFT) |
+                       (exynos4x12_clkdiv_dmc0[i][5] <<
+                                       EXYNOS4_CLKDIV_DMC0_DMCP_SHIFT));
+
+               data->dmc_divtable[i] = tmp;
+       }
+
+       tmp = 0; /* Max voltages for the reliability of the unknown */
+
+       if (tmp > 8)
+               tmp = 0;
+       pr_debug("ASV Group of Exynos4x12 is %d\n", tmp);
+
+       for (i = 0; i < EX4x12_LV_NUM; i++) {
+               exynos4x12_mifclk_table[i].volt =
+                       exynos4x12_mif_step_50[tmp][i];
+               exynos4x12_intclk_table[i].volt =
+                       exynos4x12_int_volt[tmp][i];
+       }
+
+       for (i = 0; i < EX4x12_LV_NUM; i++) {
+               ret = dev_pm_opp_add(data->dev, exynos4x12_mifclk_table[i].clk,
+                             exynos4x12_mifclk_table[i].volt);
+               if (ret) {
+                       dev_err(data->dev, "Fail to add opp entries.\n");
+                       return ret;
+               }
+       }
+
+       return 0;
+}
+
+static int exynos4_busfreq_pm_notifier_event(struct notifier_block *this,
+               unsigned long event, void *ptr)
+{
+       struct busfreq_data *data = container_of(this, struct busfreq_data,
+                                                pm_notifier);
+       struct dev_pm_opp *opp;
+       struct busfreq_opp_info new_oppinfo;
+       unsigned long maxfreq = ULONG_MAX;
+       int err = 0;
+
+       switch (event) {
+       case PM_SUSPEND_PREPARE:
+               /* Set Fastest and Deactivate DVFS */
+               mutex_lock(&data->lock);
+
+               data->disabled = true;
+
+               rcu_read_lock();
+               opp = dev_pm_opp_find_freq_floor(data->dev, &maxfreq);
+               if (IS_ERR(opp)) {
+                       rcu_read_unlock();
+                       dev_err(data->dev, "%s: unable to find a min freq\n",
+                               __func__);
+                       mutex_unlock(&data->lock);
+                       return PTR_ERR(opp);
+               }
+               new_oppinfo.rate = dev_pm_opp_get_freq(opp);
+               new_oppinfo.volt = dev_pm_opp_get_voltage(opp);
+               rcu_read_unlock();
+
+               err = exynos4_bus_setvolt(data, &new_oppinfo,
+                                         &data->curr_oppinfo);
+               if (err)
+                       goto unlock;
+
+               switch (data->type) {
+               case TYPE_BUSF_EXYNOS4210:
+                       err = exynos4210_set_busclk(data, &new_oppinfo);
+                       break;
+               case TYPE_BUSF_EXYNOS4x12:
+                       err = exynos4x12_set_busclk(data, &new_oppinfo);
+                       break;
+               default:
+                       err = -EINVAL;
+               }
+               if (err)
+                       goto unlock;
+
+               data->curr_oppinfo = new_oppinfo;
+unlock:
+               mutex_unlock(&data->lock);
+               if (err)
+                       return err;
+               return NOTIFY_OK;
+       case PM_POST_RESTORE:
+       case PM_POST_SUSPEND:
+               /* Reactivate */
+               mutex_lock(&data->lock);
+               data->disabled = false;
+               mutex_unlock(&data->lock);
+               return NOTIFY_OK;
+       }
+
+       return NOTIFY_DONE;
+}
+
+static int exynos4_busfreq_probe(struct platform_device *pdev)
+{
+       struct busfreq_data *data;
+       struct busfreq_ppmu_data *ppmu_data;
+       struct dev_pm_opp *opp;
+       struct device *dev = &pdev->dev;
+       int err = 0;
+
+       data = devm_kzalloc(&pdev->dev, sizeof(struct busfreq_data), GFP_KERNEL);
+       if (data == NULL) {
+               dev_err(dev, "Cannot allocate memory.\n");
+               return -ENOMEM;
+       }
+
+       ppmu_data = &data->ppmu_data;
+       ppmu_data->ppmu_end = PPMU_END;
+       ppmu_data->ppmu = devm_kzalloc(dev,
+                                      sizeof(struct exynos_ppmu) * PPMU_END,
+                                      GFP_KERNEL);
+       if (!ppmu_data->ppmu) {
+               dev_err(dev, "Failed to allocate memory for exynos_ppmu\n");
+               return -ENOMEM;
+       }
+
+       data->type = pdev->id_entry->driver_data;
+       ppmu_data->ppmu[PPMU_DMC0].hw_base = S5P_VA_DMC0;
+       ppmu_data->ppmu[PPMU_DMC1].hw_base = S5P_VA_DMC1;
+       data->pm_notifier.notifier_call = exynos4_busfreq_pm_notifier_event;
+       data->dev = dev;
+       mutex_init(&data->lock);
+
+       switch (data->type) {
+       case TYPE_BUSF_EXYNOS4210:
+               err = exynos4210_init_tables(data);
+               break;
+       case TYPE_BUSF_EXYNOS4x12:
+               err = exynos4x12_init_tables(data);
+               break;
+       default:
+               dev_err(dev, "Cannot determine the device id %d\n", data->type);
+               err = -EINVAL;
+       }
+       if (err) {
+               dev_err(dev, "Cannot initialize busfreq table %d\n",
+                            data->type);
+               return err;
+       }
+
+       data->vdd_int = devm_regulator_get(dev, "vdd_int");
+       if (IS_ERR(data->vdd_int)) {
+               dev_err(dev, "Cannot get the regulator \"vdd_int\"\n");
+               return PTR_ERR(data->vdd_int);
+       }
+       if (data->type == TYPE_BUSF_EXYNOS4x12) {
+               data->vdd_mif = devm_regulator_get(dev, "vdd_mif");
+               if (IS_ERR(data->vdd_mif)) {
+                       dev_err(dev, "Cannot get the regulator \"vdd_mif\"\n");
+                       return PTR_ERR(data->vdd_mif);
+               }
+       }
+
+       rcu_read_lock();
+       opp = dev_pm_opp_find_freq_floor(dev,
+                                        &exynos4_devfreq_profile.initial_freq);
+       if (IS_ERR(opp)) {
+               rcu_read_unlock();
+               dev_err(dev, "Invalid initial frequency %lu kHz.\n",
+                       exynos4_devfreq_profile.initial_freq);
+               return PTR_ERR(opp);
+       }
+       data->curr_oppinfo.rate = dev_pm_opp_get_freq(opp);
+       data->curr_oppinfo.volt = dev_pm_opp_get_voltage(opp);
+       rcu_read_unlock();
+
+       platform_set_drvdata(pdev, data);
+
+       data->devfreq = devm_devfreq_add_device(dev, &exynos4_devfreq_profile,
+                                          "simple_ondemand", NULL);
+       if (IS_ERR(data->devfreq))
+               return PTR_ERR(data->devfreq);
+
+       /*
+        * Start PPMU (Performance Profiling Monitoring Unit) to check
+        * utilization of each IP in the Exynos4 SoC.
+        */
+       busfreq_mon_reset(ppmu_data);
+
+       /* Register opp_notifier for Exynos4 busfreq */
+       err = devm_devfreq_register_opp_notifier(dev, data->devfreq);
+       if (err < 0) {
+               dev_err(dev, "Failed to register opp notifier\n");
+               return err;
+       }
+
+       /* Register pm_notifier for Exynos4 busfreq */
+       err = register_pm_notifier(&data->pm_notifier);
+       if (err) {
+               dev_err(dev, "Failed to setup pm notifier\n");
+               return err;
+       }
+
+       return 0;
+}
+
+static int exynos4_busfreq_remove(struct platform_device *pdev)
+{
+       struct busfreq_data *data = platform_get_drvdata(pdev);
+
+       /* Unregister all of notifier chain */
+       unregister_pm_notifier(&data->pm_notifier);
+
+       return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int exynos4_busfreq_resume(struct device *dev)
+{
+       struct busfreq_data *data = dev_get_drvdata(dev);
+       struct busfreq_ppmu_data *ppmu_data = &data->ppmu_data;
+
+       busfreq_mon_reset(ppmu_data);
+       return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(exynos4_busfreq_pm_ops, NULL, exynos4_busfreq_resume);
+
+static const struct platform_device_id exynos4_busfreq_id[] = {
+       { "exynos4210-busfreq", TYPE_BUSF_EXYNOS4210 },
+       { "exynos4412-busfreq", TYPE_BUSF_EXYNOS4x12 },
+       { "exynos4212-busfreq", TYPE_BUSF_EXYNOS4x12 },
+       { },
+};
+
+static struct platform_driver exynos4_busfreq_driver = {
+       .probe  = exynos4_busfreq_probe,
+       .remove = exynos4_busfreq_remove,
+       .id_table = exynos4_busfreq_id,
+       .driver = {
+               .name   = "exynos4-busfreq",
+               .pm     = &exynos4_busfreq_pm_ops,
+       },
+};
+
+static int __init exynos4_busfreq_init(void)
+{
+       return platform_driver_register(&exynos4_busfreq_driver);
+}
+late_initcall(exynos4_busfreq_init);
+
+static void __exit exynos4_busfreq_exit(void)
+{
+       platform_driver_unregister(&exynos4_busfreq_driver);
+}
+module_exit(exynos4_busfreq_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("EXYNOS4 busfreq driver with devfreq framework");
+MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");