Patchwork [U-Boot,2/8,v2] EXYNOS5: TMU: Add driver for Thermal Management Unit

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Submitter Hatim RV
Date Nov. 7, 2012, 1:08 p.m.
Message ID <1352293728-9958-3-git-send-email-hatim.rv@samsung.com>
Download mbox | patch
Permalink /patch/197664/
State Changes Requested
Delegated to: Minkyu Kang
Headers show

Comments

Hatim RV - Nov. 7, 2012, 1:08 p.m.
From: Akshay Saraswat <akshay.s@samsung.com>

Adding Exynos Thermal Management Unit driver to monitor SOC
temperature and take actions corresponding to states of TMU.
System will shutdown if tripping temperature is reached.

Signed-off-by: Akshay Saraswat <akshay.s@samsung.com>
Acked-by: Simon Glass <sjg@chromium.org>
---
Changes since v1:
	- Added new generic header file include/tmu.h
	- Added Acked-by: Simon Glass

 arch/arm/include/asm/arch-exynos/exynos-tmu.h |   58 +++++
 drivers/power/Makefile                        |    1 +
 drivers/power/exynos-tmu.c                    |  297 +++++++++++++++++++++++++
 include/tmu.h                                 |   46 ++++
 4 files changed, 402 insertions(+), 0 deletions(-)
 create mode 100644 arch/arm/include/asm/arch-exynos/exynos-tmu.h
 create mode 100644 drivers/power/exynos-tmu.c
 create mode 100644 include/tmu.h
Simon Glass - Nov. 7, 2012, 9:50 p.m.
Hi Hatim,

On Wed, Nov 7, 2012 at 5:08 AM, Hatim Ali <hatim.rv@samsung.com> wrote:
> From: Akshay Saraswat <akshay.s@samsung.com>
>
> Adding Exynos Thermal Management Unit driver to monitor SOC
> temperature and take actions corresponding to states of TMU.
> System will shutdown if tripping temperature is reached.
>
> Signed-off-by: Akshay Saraswat <akshay.s@samsung.com>
> Acked-by: Simon Glass <sjg@chromium.org>
> ---
> Changes since v1:
>         - Added new generic header file include/tmu.h
>         - Added Acked-by: Simon Glass
>
>  arch/arm/include/asm/arch-exynos/exynos-tmu.h |   58 +++++
>  drivers/power/Makefile                        |    1 +
>  drivers/power/exynos-tmu.c                    |  297 +++++++++++++++++++++++++
>  include/tmu.h                                 |   46 ++++
>  4 files changed, 402 insertions(+), 0 deletions(-)
>  create mode 100644 arch/arm/include/asm/arch-exynos/exynos-tmu.h
>  create mode 100644 drivers/power/exynos-tmu.c
>  create mode 100644 include/tmu.h
>
> diff --git a/arch/arm/include/asm/arch-exynos/exynos-tmu.h b/arch/arm/include/asm/arch-exynos/exynos-tmu.h
> new file mode 100644
> index 0000000..adfaf0d
> --- /dev/null
> +++ b/arch/arm/include/asm/arch-exynos/exynos-tmu.h
> @@ -0,0 +1,58 @@
> +/*
> + * Copyright (c) 2012 Samsung Electronics Co., Ltd.
> + *      http://www.samsung.com
> + * Akshay Saraswat <akshay.s@samsung.com>
> + *
> + * EXYNOS - Thermal Management Unit
> + *
> + * See file CREDITS for list of people who contributed to this
> + * project.
> + *
> + * 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.
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
> + * MA 02111-1307 USA
> + */
> +
> +#ifndef __ASM_ARCH_THERMAL_H
> +#define __ASM_ARCH_THERMAL_H

Suggest renaming this to ASM_ARCH_TMU_H

> +
> +struct tmu_reg {
> +       unsigned triminfo;
> +       unsigned rsvd1;
> +       unsigned rsvd2;
> +       unsigned rsvd3;
> +       unsigned rsvd4;
> +       unsigned triminfo_control;
> +       unsigned rsvd5;
> +       unsigned rsvd6;
> +       unsigned tmu_control;
> +       unsigned rsvd7;
> +       unsigned tmu_status;
> +       unsigned sampling_internal;
> +       unsigned counter_value0;
> +       unsigned counter_value1;
> +       unsigned rsvd8;
> +       unsigned rsvd9;
> +       unsigned current_temp;
> +       unsigned rsvd10;
> +       unsigned rsvd11;
> +       unsigned rsvd12;
> +       unsigned threshold_temp_rise;
> +       unsigned threshold_temp_fall;
> +       unsigned rsvd13;
> +       unsigned rsvd14;
> +       unsigned past_temp3_0;
> +       unsigned past_temp7_4;
> +       unsigned past_temp11_8;
> +       unsigned past_temp15_12;
> +       unsigned inten;
> +       unsigned intstat;
> +       unsigned intclear;
> +       unsigned rsvd15;
> +       unsigned emul_con;
> +};
> +#endif /* __ASM_ARCH_THERMAL_H */
> diff --git a/drivers/power/Makefile b/drivers/power/Makefile
> index 6bf388c..192a7cb 100644
> --- a/drivers/power/Makefile
> +++ b/drivers/power/Makefile
> @@ -30,6 +30,7 @@ COBJS-$(CONFIG_TPS6586X_POWER)        += tps6586x.o
>  COBJS-$(CONFIG_TWL4030_POWER)  += twl4030.o
>  COBJS-$(CONFIG_TWL6030_POWER)  += twl6030.o
>  COBJS-$(CONFIG_TWL6035_POWER)  += twl6035.o
> +COBJS-$(CONFIG_EXYNOS_TMU)     += exynos-tmu.o
>
>  COBJS  := $(COBJS-y)
>  SRCS   := $(COBJS:.o=.c)
> diff --git a/drivers/power/exynos-tmu.c b/drivers/power/exynos-tmu.c
> new file mode 100644
> index 0000000..ce71408
> --- /dev/null
> +++ b/drivers/power/exynos-tmu.c
> @@ -0,0 +1,297 @@
> +/*
> + * Copyright (c) 2012 Samsung Electronics Co., Ltd.
> + *      http://www.samsung.com
> + * Akshay Saraswat <akshay.s@samsung.com>
> + *
> + * EXYNOS - Thermal Management Unit
> + *
> + * See file CREDITS for list of people who contributed to this
> + * project.
> + *
> + * 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.
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
> + * MA 02111-1307 USA
> + */
> +
> +#include <common.h>
> +#include <errno.h>
> +#include <fdtdec.h>
> +#include <tmu.h>
> +#include <asm/arch/exynos-tmu.h>
> +
> +#define TRIMINFO_RELOAD                1
> +#define CORE_EN                        1
> +
> +#define INTEN_RISE0            1
> +#define INTEN_RISE1            (1 << 4)
> +#define INTEN_RISE2            (1 << 8)
> +#define INTEN_FALL0            (1 << 16)
> +#define INTEN_FALL1            (1 << 20)
> +#define INTEN_FALL2            (1 << 24)
> +
> +#define TRIM_INFO_MASK         0xff
> +
> +#define INTCLEAR_RISE0         1
> +#define INTCLEAR_RISE1         (1 << 4)
> +#define INTCLEAR_RISE2         (1 << 8)
> +#define INTCLEAR_FALL0         (1 << 16)
> +#define INTCLEAR_FALL1         (1 << 20)
> +#define INTCLEAR_FALL2         (1 << 24)
> +#define INTCLEARALL            (INTCLEAR_RISE0 | INTCLEAR_RISE1 | \
> +                                INTCLEAR_RISE2 | INTCLEAR_FALL0 | \
> +                                INTCLEAR_FALL1 | INTCLEAR_FALL2)
> +
> +/* Tmeperature threshold values for various thermal events */
> +struct temperature_params {
> +       /* minimum value in temperature code range */
> +       unsigned int min_val;
> +       /* maximum value in temperature code range */
> +       unsigned int max_val;
> +       /* temperature threshold to start warning */
> +       unsigned int start_warning;
> +       /* temperature threshold CPU tripping */
> +       unsigned int start_tripping;
> +};
> +
> +/* Pre-defined values and thresholds for calibration of current temperature */
> +struct tmu_data {
> +       /* pre-defined temperature thresholds */
> +       struct temperature_params ts;
> +       /* pre-defined efuse range minimum value */
> +       unsigned int efuse_min_value;
> +       /* pre-defined efuse value for temperature calibration */
> +       unsigned int efuse_value;
> +       /* pre-defined efuse range maximum value */
> +       unsigned int efuse_max_value;
> +       /* current temperature sensing slope */
> +       unsigned int slope;
> +};
> +
> +/* TMU device specific details and status */
> +struct tmu_info {
> +       /* base Address for the TMU */
> +       unsigned tmu_base;
> +       /* mux Address for the TMU */
> +       int tmu_mux;
> +       /* pre-defined values for calibration and thresholds */
> +       struct tmu_data data;
> +       /* value required for triminfo_25 calibration */
> +       unsigned int te1;
> +       /* value required for triminfo_85 calibration */
> +       unsigned int te2;
> +       /* TMU DC value for threshold calculation */
> +       int dc_value;
> +       /* enum value indicating status of the TMU */
> +       int tmu_state;
> +};
> +
> +/* Global struct tmu_info variable to store init values */
> +static struct tmu_info gbl_info;
> +
> +/*
> + * After reading temperature code from register, compensating
> + * its value and calculating celsius temperatue,
> + * get current temperatue.
> + *
> + * @return     current temperature of the chip as sensed by TMU
> + */
> +int get_cur_temp(struct tmu_info *info)
> +{
> +       int cur_temp;
> +       struct tmu_reg *reg = (struct tmu_reg *)info->tmu_base;
> +
> +       /* Temperature code range between min 25 and max 125 */
> +       cur_temp = readl(&reg->current_temp) & 0xff;
> +
> +       /* Calibrate current temperature */
> +       if (cur_temp)
> +               cur_temp = cur_temp - info->te1 + info->dc_value;
> +
> +       return cur_temp;
> +}
> +
> +/*
> + * Monitors status of the TMU device and exynos temperature
> + *
> + * @param temp pointer to the current temperature value
> + * @return     enum tmu_status_t value, code indicating event to execute
> + */
> +enum tmu_status_t tmu_monitor(int *temp)
> +{
> +       if (gbl_info.tmu_state == TMU_STATUS_INIT)
> +               return -1;
> +
> +       int cur_temp;
> +       struct tmu_data *data = &gbl_info.data;
> +
> +       /* Read current temperature of the SOC */
> +       cur_temp = get_cur_temp(&gbl_info);
> +       *temp = cur_temp;
> +
> +       /* Temperature code lies between min 25 and max 125 */
> +       if (cur_temp >= data->ts.start_tripping &&
> +                       cur_temp <= data->ts.max_val)
> +               return TMU_STATUS_TRIPPED;
> +       else if (cur_temp >= data->ts.start_warning)
> +               return TMU_STATUS_WARNING;
> +       else if (cur_temp < data->ts.start_warning &&
> +                       cur_temp >= data->ts.min_val)
> +               return TMU_STATUS_NORMAL;
> +       /* Temperature code does not lie between min 25 and max 125 */
> +       else {
> +               gbl_info.tmu_state = TMU_STATUS_INIT;
> +               debug("EXYNOS_TMU: Thermal reading failed\n");
> +               return -1;
> +       }
> +       return 0;
> +}
> +
> +/*
> + * Get TMU specific pre-defined values from FDT
> + *
> + * @param info pointer to the tmu_info struct
> + * @param blob  FDT blob
> + * @return     int value, 0 for success
> + */
> +int get_tmu_fdt_values(struct tmu_info *info, const void *blob)
> +{
> +       int node;
> +       int error = 0;
> +
> +       /* Get the node from FDT for TMU */
> +       node = fdtdec_next_compatible(blob, 0,
> +                                     COMPAT_SAMSUNG_EXYNOS_TMU);
> +       if (node < 0) {
> +               debug("EXYNOS_TMU: No node for tmu in device tree\n");
> +               return -1;
> +       }
> +
> +       /*
> +        * Get the pre-defined TMU specific values from FDT.
> +        * All of these are expected to be correct otherwise
> +        * miscalculation of register values in tmu_setup_parameters
> +        * may result in misleading current temperature.
> +        */
> +       info->tmu_base = fdtdec_get_addr(blob, node, "reg");
> +       if (info->tmu_base == FDT_ADDR_T_NONE) {
> +               debug("%s: Missing tmu-base\n", __func__);
> +               return -1;
> +       }
> +       info->tmu_mux = fdtdec_get_int(blob,
> +                               node, "samsung,mux", -1);
> +       error |= info->tmu_mux;
> +       info->data.ts.min_val = fdtdec_get_int(blob,
> +                               node, "samsung,min-temp", -1);
> +       error |= info->data.ts.min_val;
> +       info->data.ts.max_val = fdtdec_get_int(blob,
> +                               node, "samsung,max-temp", -1);
> +       error |= info->data.ts.max_val;
> +       info->data.ts.start_warning = fdtdec_get_int(blob,
> +                               node, "samsung,start-warning", -1);
> +       error |= info->data.ts.start_warning;
> +       info->data.ts.start_tripping = fdtdec_get_int(blob,
> +                               node, "samsung,start-tripping", -1);
> +       error |= info->data.ts.start_tripping;
> +       info->data.efuse_min_value = fdtdec_get_int(blob,
> +                               node, "samsung,efuse-min-value", -1);
> +       error |= info->data.efuse_min_value;
> +       info->data.efuse_value = fdtdec_get_int(blob,
> +                               node, "samsung,efuse-value", -1);
> +       error |= info->data.efuse_value;
> +       info->data.efuse_max_value = fdtdec_get_int(blob,
> +                               node, "samsung,efuse-max-value", -1);
> +       error |= info->data.efuse_max_value;
> +       info->data.slope = fdtdec_get_int(blob,
> +                               node, "samsung,slope", -1);
> +       error |= info->data.slope;
> +       info->dc_value = fdtdec_get_int(blob,
> +                               node, "samsung,dc-value", -1);
> +       error |= info->dc_value;
> +
> +       if (error == -1) {
> +               debug("fail to get tmu node properties\n");
> +               return -1;
> +       }
> +
> +       return 0;
> +}
> +
> +/*
> + * Calibrate and calculate threshold values and
> + * enable interrupt levels
> + *
> + * @param      info pointer to the tmu_info struct
> + */
> +void tmu_setup_parameters(struct tmu_info *info)
> +{
> +       unsigned int te_temp, con;
> +       unsigned int warning_temp, trip_temp;
> +       unsigned int cooling_temp;
> +       unsigned int rising_value;
> +       struct tmu_data *data = &info->data;
> +       struct tmu_reg *reg = (struct tmu_reg *)info->tmu_base;
> +
> +       /* Must reload for using efuse value at EXYNOS */
> +       writel(TRIMINFO_RELOAD, &reg->triminfo_control);
> +
> +       /* Get the compensation parameter */
> +       te_temp = readl(&reg->triminfo);
> +       info->te1 = te_temp & TRIM_INFO_MASK;
> +       info->te2 = ((te_temp >> 8) & TRIM_INFO_MASK);
> +
> +       if ((data->efuse_min_value > info->te1) ||
> +                       (info->te1 > data->efuse_max_value)
> +                       ||  (info->te2 != 0))
> +               info->te1 = data->efuse_value;
> +
> +       /* Get RISING & FALLING Threshold value */
> +       warning_temp = data->ts.start_warning
> +                       + info->te1 - info->dc_value;
> +       trip_temp = data->ts.start_tripping
> +                       + info->te1 - info->dc_value;
> +       cooling_temp = 0;
> +
> +       rising_value = ((warning_temp << 8) | (trip_temp << 16));
> +
> +       /* Set interrupt level */
> +       writel(rising_value, &reg->threshold_temp_rise);
> +       writel(cooling_temp, &reg->threshold_temp_fall);
> +
> +       /*
> +        * Need to init all regsiter setting after getting parameter info
> +        * [28:23] vref [11:8] slope - Tunning parameter
> +        */
> +       writel(data->slope, &reg->tmu_control);
> +
> +       writel(INTCLEARALL, &reg->intclear);
> +       /* TMU core enable */
> +       con = readl(&reg->tmu_control);
> +       con |= (info->tmu_mux << 20) | CORE_EN;
> +
> +       writel(con, &reg->tmu_control);
> +
> +       /* LEV0 LEV1 LEV2 interrupt enable */
> +       writel(INTEN_RISE0 | INTEN_RISE1 | INTEN_RISE2, &reg->inten);
> +}
> +
> +/*
> + * Initialize TMU device
> + *
> + * @param blob  FDT blob
> + * @return     int value, 0 for success
> + */
> +int tmu_init(const void *blob)
> +{
> +       gbl_info.tmu_state = TMU_STATUS_INIT;
> +       if (get_tmu_fdt_values(&gbl_info, blob) < 0)
> +               return -1;
> +
> +       tmu_setup_parameters(&gbl_info);
> +       gbl_info.tmu_state = TMU_STATUS_NORMAL;
> +
> +       return 0;
> +}
> diff --git a/include/tmu.h b/include/tmu.h
> new file mode 100644
> index 0000000..ba813ce
> --- /dev/null
> +++ b/include/tmu.h
> @@ -0,0 +1,46 @@
> +/*
> + * Copyright (c) 2012 Samsung Electronics Co., Ltd.
> + *      http://www.samsung.com
> + * Akshay Saraswat <akshay.s@samsung.com>
> + *
> + * Thermal Management Unit
> + *
> + * See file CREDITS for list of people who contributed to this
> + * project.
> + *
> + * 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.
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
> + * MA 02111-1307 USA
> + */
> +
> +#ifndef _THERMAL_H
> +#define _THERMAL_H

The guard here should be _TMU_H I think.

> +
> +enum tmu_status_t {
> +       TMU_STATUS_INIT = 0,
> +       TMU_STATUS_NORMAL,
> +       TMU_STATUS_WARNING,
> +       TMU_STATUS_TRIPPED,
> +};
> +
> +/*
> + * Monitors status of the TMU device and exynos temperature
> + *
> + * @param temp pointer to the current temperature value
> + * @return     enum tmu_status_t value, code indicating event to execute
> + *             and -1 on error
> + */
> +enum tmu_status_t tmu_monitor(int *temp);
> +
> +/*
> + * Initialize TMU device
> + *
> + * @param blob  FDT blob
> + * @return     int value, 0 for success
> + */
> +int tmu_init(const void *blob);
> +#endif /* _THERMAL_H_ */
> --
> 1.7.2.3
>

Regards,
Simon

Patch

diff --git a/arch/arm/include/asm/arch-exynos/exynos-tmu.h b/arch/arm/include/asm/arch-exynos/exynos-tmu.h
new file mode 100644
index 0000000..adfaf0d
--- /dev/null
+++ b/arch/arm/include/asm/arch-exynos/exynos-tmu.h
@@ -0,0 +1,58 @@ 
+/*
+ * Copyright (c) 2012 Samsung Electronics Co., Ltd.
+ *      http://www.samsung.com
+ * Akshay Saraswat <akshay.s@samsung.com>
+ *
+ * EXYNOS - Thermal Management Unit
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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.
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef __ASM_ARCH_THERMAL_H
+#define __ASM_ARCH_THERMAL_H
+
+struct tmu_reg {
+	unsigned triminfo;
+	unsigned rsvd1;
+	unsigned rsvd2;
+	unsigned rsvd3;
+	unsigned rsvd4;
+	unsigned triminfo_control;
+	unsigned rsvd5;
+	unsigned rsvd6;
+	unsigned tmu_control;
+	unsigned rsvd7;
+	unsigned tmu_status;
+	unsigned sampling_internal;
+	unsigned counter_value0;
+	unsigned counter_value1;
+	unsigned rsvd8;
+	unsigned rsvd9;
+	unsigned current_temp;
+	unsigned rsvd10;
+	unsigned rsvd11;
+	unsigned rsvd12;
+	unsigned threshold_temp_rise;
+	unsigned threshold_temp_fall;
+	unsigned rsvd13;
+	unsigned rsvd14;
+	unsigned past_temp3_0;
+	unsigned past_temp7_4;
+	unsigned past_temp11_8;
+	unsigned past_temp15_12;
+	unsigned inten;
+	unsigned intstat;
+	unsigned intclear;
+	unsigned rsvd15;
+	unsigned emul_con;
+};
+#endif /* __ASM_ARCH_THERMAL_H */
diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index 6bf388c..192a7cb 100644
--- a/drivers/power/Makefile
+++ b/drivers/power/Makefile
@@ -30,6 +30,7 @@  COBJS-$(CONFIG_TPS6586X_POWER)	+= tps6586x.o
 COBJS-$(CONFIG_TWL4030_POWER)	+= twl4030.o
 COBJS-$(CONFIG_TWL6030_POWER)	+= twl6030.o
 COBJS-$(CONFIG_TWL6035_POWER)	+= twl6035.o
+COBJS-$(CONFIG_EXYNOS_TMU)	+= exynos-tmu.o
 
 COBJS	:= $(COBJS-y)
 SRCS 	:= $(COBJS:.o=.c)
diff --git a/drivers/power/exynos-tmu.c b/drivers/power/exynos-tmu.c
new file mode 100644
index 0000000..ce71408
--- /dev/null
+++ b/drivers/power/exynos-tmu.c
@@ -0,0 +1,297 @@ 
+/*
+ * Copyright (c) 2012 Samsung Electronics Co., Ltd.
+ *      http://www.samsung.com
+ * Akshay Saraswat <akshay.s@samsung.com>
+ *
+ * EXYNOS - Thermal Management Unit
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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.
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <fdtdec.h>
+#include <tmu.h>
+#include <asm/arch/exynos-tmu.h>
+
+#define TRIMINFO_RELOAD		1
+#define CORE_EN			1
+
+#define INTEN_RISE0		1
+#define INTEN_RISE1		(1 << 4)
+#define INTEN_RISE2		(1 << 8)
+#define INTEN_FALL0		(1 << 16)
+#define INTEN_FALL1		(1 << 20)
+#define INTEN_FALL2		(1 << 24)
+
+#define TRIM_INFO_MASK		0xff
+
+#define INTCLEAR_RISE0		1
+#define INTCLEAR_RISE1		(1 << 4)
+#define INTCLEAR_RISE2		(1 << 8)
+#define INTCLEAR_FALL0		(1 << 16)
+#define INTCLEAR_FALL1		(1 << 20)
+#define INTCLEAR_FALL2		(1 << 24)
+#define INTCLEARALL		(INTCLEAR_RISE0 | INTCLEAR_RISE1 | \
+				 INTCLEAR_RISE2 | INTCLEAR_FALL0 | \
+				 INTCLEAR_FALL1 | INTCLEAR_FALL2)
+
+/* Tmeperature threshold values for various thermal events */
+struct temperature_params {
+	/* minimum value in temperature code range */
+	unsigned int min_val;
+	/* maximum value in temperature code range */
+	unsigned int max_val;
+	/* temperature threshold to start warning */
+	unsigned int start_warning;
+	/* temperature threshold CPU tripping */
+	unsigned int start_tripping;
+};
+
+/* Pre-defined values and thresholds for calibration of current temperature */
+struct tmu_data {
+	/* pre-defined temperature thresholds */
+	struct temperature_params ts;
+	/* pre-defined efuse range minimum value */
+	unsigned int efuse_min_value;
+	/* pre-defined efuse value for temperature calibration */
+	unsigned int efuse_value;
+	/* pre-defined efuse range maximum value */
+	unsigned int efuse_max_value;
+	/* current temperature sensing slope */
+	unsigned int slope;
+};
+
+/* TMU device specific details and status */
+struct tmu_info {
+	/* base Address for the TMU */
+	unsigned tmu_base;
+	/* mux Address for the TMU */
+	int tmu_mux;
+	/* pre-defined values for calibration and thresholds */
+	struct tmu_data data;
+	/* value required for triminfo_25 calibration */
+	unsigned int te1;
+	/* value required for triminfo_85 calibration */
+	unsigned int te2;
+	/* TMU DC value for threshold calculation */
+	int dc_value;
+	/* enum value indicating status of the TMU */
+	int tmu_state;
+};
+
+/* Global struct tmu_info variable to store init values */
+static struct tmu_info gbl_info;
+
+/*
+ * After reading temperature code from register, compensating
+ * its value and calculating celsius temperatue,
+ * get current temperatue.
+ *
+ * @return	current temperature of the chip as sensed by TMU
+ */
+int get_cur_temp(struct tmu_info *info)
+{
+	int cur_temp;
+	struct tmu_reg *reg = (struct tmu_reg *)info->tmu_base;
+
+	/* Temperature code range between min 25 and max 125 */
+	cur_temp = readl(&reg->current_temp) & 0xff;
+
+	/* Calibrate current temperature */
+	if (cur_temp)
+		cur_temp = cur_temp - info->te1 + info->dc_value;
+
+	return cur_temp;
+}
+
+/*
+ * Monitors status of the TMU device and exynos temperature
+ *
+ * @param temp	pointer to the current temperature value
+ * @return	enum tmu_status_t value, code indicating event to execute
+ */
+enum tmu_status_t tmu_monitor(int *temp)
+{
+	if (gbl_info.tmu_state == TMU_STATUS_INIT)
+		return -1;
+
+	int cur_temp;
+	struct tmu_data *data = &gbl_info.data;
+
+	/* Read current temperature of the SOC */
+	cur_temp = get_cur_temp(&gbl_info);
+	*temp = cur_temp;
+
+	/* Temperature code lies between min 25 and max 125 */
+	if (cur_temp >= data->ts.start_tripping &&
+			cur_temp <= data->ts.max_val)
+		return TMU_STATUS_TRIPPED;
+	else if (cur_temp >= data->ts.start_warning)
+		return TMU_STATUS_WARNING;
+	else if (cur_temp < data->ts.start_warning &&
+			cur_temp >= data->ts.min_val)
+		return TMU_STATUS_NORMAL;
+	/* Temperature code does not lie between min 25 and max 125 */
+	else {
+		gbl_info.tmu_state = TMU_STATUS_INIT;
+		debug("EXYNOS_TMU: Thermal reading failed\n");
+		return -1;
+	}
+	return 0;
+}
+
+/*
+ * Get TMU specific pre-defined values from FDT
+ *
+ * @param info	pointer to the tmu_info struct
+ * @param blob  FDT blob
+ * @return	int value, 0 for success
+ */
+int get_tmu_fdt_values(struct tmu_info *info, const void *blob)
+{
+	int node;
+	int error = 0;
+
+	/* Get the node from FDT for TMU */
+	node = fdtdec_next_compatible(blob, 0,
+				      COMPAT_SAMSUNG_EXYNOS_TMU);
+	if (node < 0) {
+		debug("EXYNOS_TMU: No node for tmu in device tree\n");
+		return -1;
+	}
+
+	/*
+	 * Get the pre-defined TMU specific values from FDT.
+	 * All of these are expected to be correct otherwise
+	 * miscalculation of register values in tmu_setup_parameters
+	 * may result in misleading current temperature.
+	 */
+	info->tmu_base = fdtdec_get_addr(blob, node, "reg");
+	if (info->tmu_base == FDT_ADDR_T_NONE) {
+		debug("%s: Missing tmu-base\n", __func__);
+		return -1;
+	}
+	info->tmu_mux = fdtdec_get_int(blob,
+				node, "samsung,mux", -1);
+	error |= info->tmu_mux;
+	info->data.ts.min_val = fdtdec_get_int(blob,
+				node, "samsung,min-temp", -1);
+	error |= info->data.ts.min_val;
+	info->data.ts.max_val = fdtdec_get_int(blob,
+				node, "samsung,max-temp", -1);
+	error |= info->data.ts.max_val;
+	info->data.ts.start_warning = fdtdec_get_int(blob,
+				node, "samsung,start-warning", -1);
+	error |= info->data.ts.start_warning;
+	info->data.ts.start_tripping = fdtdec_get_int(blob,
+				node, "samsung,start-tripping", -1);
+	error |= info->data.ts.start_tripping;
+	info->data.efuse_min_value = fdtdec_get_int(blob,
+				node, "samsung,efuse-min-value", -1);
+	error |= info->data.efuse_min_value;
+	info->data.efuse_value = fdtdec_get_int(blob,
+				node, "samsung,efuse-value", -1);
+	error |= info->data.efuse_value;
+	info->data.efuse_max_value = fdtdec_get_int(blob,
+				node, "samsung,efuse-max-value", -1);
+	error |= info->data.efuse_max_value;
+	info->data.slope = fdtdec_get_int(blob,
+				node, "samsung,slope", -1);
+	error |= info->data.slope;
+	info->dc_value = fdtdec_get_int(blob,
+				node, "samsung,dc-value", -1);
+	error |= info->dc_value;
+
+	if (error == -1) {
+		debug("fail to get tmu node properties\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * Calibrate and calculate threshold values and
+ * enable interrupt levels
+ *
+ * @param	info pointer to the tmu_info struct
+ */
+void tmu_setup_parameters(struct tmu_info *info)
+{
+	unsigned int te_temp, con;
+	unsigned int warning_temp, trip_temp;
+	unsigned int cooling_temp;
+	unsigned int rising_value;
+	struct tmu_data *data = &info->data;
+	struct tmu_reg *reg = (struct tmu_reg *)info->tmu_base;
+
+	/* Must reload for using efuse value at EXYNOS */
+	writel(TRIMINFO_RELOAD, &reg->triminfo_control);
+
+	/* Get the compensation parameter */
+	te_temp = readl(&reg->triminfo);
+	info->te1 = te_temp & TRIM_INFO_MASK;
+	info->te2 = ((te_temp >> 8) & TRIM_INFO_MASK);
+
+	if ((data->efuse_min_value > info->te1) ||
+			(info->te1 > data->efuse_max_value)
+			||  (info->te2 != 0))
+		info->te1 = data->efuse_value;
+
+	/* Get RISING & FALLING Threshold value */
+	warning_temp = data->ts.start_warning
+			+ info->te1 - info->dc_value;
+	trip_temp = data->ts.start_tripping
+			+ info->te1 - info->dc_value;
+	cooling_temp = 0;
+
+	rising_value = ((warning_temp << 8) | (trip_temp << 16));
+
+	/* Set interrupt level */
+	writel(rising_value, &reg->threshold_temp_rise);
+	writel(cooling_temp, &reg->threshold_temp_fall);
+
+	/*
+	 * Need to init all regsiter setting after getting parameter info
+	 * [28:23] vref [11:8] slope - Tunning parameter
+	 */
+	writel(data->slope, &reg->tmu_control);
+
+	writel(INTCLEARALL, &reg->intclear);
+	/* TMU core enable */
+	con = readl(&reg->tmu_control);
+	con |= (info->tmu_mux << 20) | CORE_EN;
+
+	writel(con, &reg->tmu_control);
+
+	/* LEV0 LEV1 LEV2 interrupt enable */
+	writel(INTEN_RISE0 | INTEN_RISE1 | INTEN_RISE2,	&reg->inten);
+}
+
+/*
+ * Initialize TMU device
+ *
+ * @param blob  FDT blob
+ * @return	int value, 0 for success
+ */
+int tmu_init(const void *blob)
+{
+	gbl_info.tmu_state = TMU_STATUS_INIT;
+	if (get_tmu_fdt_values(&gbl_info, blob) < 0)
+		return -1;
+
+	tmu_setup_parameters(&gbl_info);
+	gbl_info.tmu_state = TMU_STATUS_NORMAL;
+
+	return 0;
+}
diff --git a/include/tmu.h b/include/tmu.h
new file mode 100644
index 0000000..ba813ce
--- /dev/null
+++ b/include/tmu.h
@@ -0,0 +1,46 @@ 
+/*
+ * Copyright (c) 2012 Samsung Electronics Co., Ltd.
+ *      http://www.samsung.com
+ * Akshay Saraswat <akshay.s@samsung.com>
+ *
+ * Thermal Management Unit
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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.
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef _THERMAL_H
+#define _THERMAL_H
+
+enum tmu_status_t {
+	TMU_STATUS_INIT = 0,
+	TMU_STATUS_NORMAL,
+	TMU_STATUS_WARNING,
+	TMU_STATUS_TRIPPED,
+};
+
+/*
+ * Monitors status of the TMU device and exynos temperature
+ *
+ * @param temp	pointer to the current temperature value
+ * @return	enum tmu_status_t value, code indicating event to execute
+ *		and -1 on error
+ */
+enum tmu_status_t tmu_monitor(int *temp);
+
+/*
+ * Initialize TMU device
+ *
+ * @param blob  FDT blob
+ * @return	int value, 0 for success
+ */
+int tmu_init(const void *blob);
+#endif	/* _THERMAL_H_ */