[U-Boot] [PATCH v7 2/4] DM: thermal: Add imx thermal DM driver

[Stefano Babic <sbabic@denx.de>]

Hi Ye,



On 20/11/2014 14:14, Ye.Li wrote:
> Add a new thermal uclass for thermal sensor and implement the imx
> thermal driver basing on this uclass.

Thanks for doing this !

> 
> Signed-off-by: Ye.Li <B37916@freescale.com>
> ---
>  drivers/Makefile                 |    1 +
>  drivers/thermal/Makefile         |    9 ++
>  drivers/thermal/imx_thermal.c    |  177 ++++++++++++++++++++++++++++++++++++++
>  drivers/thermal/thermal-uclass.c |   30 +++++++
>  include/dm/uclass-id.h           |    1 +
>  include/imx_thermal.h            |   17 ++++
>  include/thermal.h                |   42 +++++++++
>  7 files changed, 277 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/Makefile b/drivers/Makefile
> index 33227c8..7683c61 100644
> --- a/drivers/Makefile
> +++ b/drivers/Makefile
> @@ -21,3 +21,4 @@ obj-y += pwm/
>  obj-y += input/
>  # SOC specific infrastructure drivers.
>  obj-y += soc/
> +obj-y += thermal/
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> new file mode 100644
> index 0000000..6d4cacd
> --- /dev/null
> +++ b/drivers/thermal/Makefile
> @@ -0,0 +1,9 @@
> +#
> +# (C) Copyright 2014 Freescale Semiconductor, Inc.
> +# Author: Nitin Garg <nitin.garg@freescale.com>
> +#
> +# SPDX-License-Identifier:	GPL-2.0+
> +#
> +
> +obj-$(CONFIG_DM_THERMAL) += thermal-uclass.o
> +obj-$(CONFIG_IMX6_THERMAL) += imx_thermal.o
> diff --git a/drivers/thermal/imx_thermal.c b/drivers/thermal/imx_thermal.c
> new file mode 100644
> index 0000000..1161585
> --- /dev/null
> +++ b/drivers/thermal/imx_thermal.c
> @@ -0,0 +1,177 @@
> +/*
> + * (C) Copyright 2014 Freescale Semiconductor, Inc.
> + * Author: Nitin Garg <nitin.garg@freescale.com>
> + *             Ye Li <Ye.Li@freescale.com>
> + *
> + * SPDX-License-Identifier:	GPL-2.0+
> + */
> +
> +#include <config.h>
> +#include <common.h>
> +#include <div64.h>
> +#include <fuse.h>
> +#include <asm/io.h>
> +#include <asm/arch/clock.h>
> +#include <dm.h>
> +#include <errno.h>
> +#include <malloc.h>
> +#include <thermal.h>
> +#include <imx_thermal.h>
> +
> +#define TEMPERATURE_MIN		-40
> +#define TEMPERATURE_HOT		80
> +#define TEMPERATURE_MAX		125
> +#define FACTOR0			10000000
> +#define FACTOR1			15976
> +#define FACTOR2			4297157
> +#define MEASURE_FREQ		327
> +
> +#define TEMPSENSE0_TEMP_CNT_SHIFT	8
> +#define TEMPSENSE0_TEMP_CNT_MASK	(0xfff << TEMPSENSE0_TEMP_CNT_SHIFT)
> +#define TEMPSENSE0_FINISHED		(1 << 2)
> +#define TEMPSENSE0_MEASURE_TEMP		(1 << 1)
> +#define TEMPSENSE0_POWER_DOWN		(1 << 0)
> +#define MISC0_REFTOP_SELBIASOFF		(1 << 3)
> +#define TEMPSENSE1_MEASURE_FREQ		0xffff
> +
> +static int read_cpu_temperature(struct udevice *dev)
> +{
> +	int temperature;
> +	unsigned int reg, n_meas;
> +	const struct imx_thermal_plat *pdata = dev_get_platdata(dev);
> +	struct anatop_regs *anatop = (struct anatop_regs *)pdata->regs;
> +	unsigned int *priv = dev_get_priv(dev);
> +	u32 fuse = *priv;
> +	int t1, n1;
> +	u32 c1, c2;
> +	u64 temp64;
> +
> +	/*
> +	 * Sensor data layout:
> +	 *   [31:20] - sensor value @ 25C
> +	 * We use universal formula now and only need sensor value @ 25C
> +	 * slope = 0.4297157 - (0.0015976 * 25C fuse)
> +	 */
> +	n1 = fuse >> 20;
> +	t1 = 25; /* t1 always 25C */
> +
> +	/*
> +	 * Derived from linear interpolation:
> +	 * slope = 0.4297157 - (0.0015976 * 25C fuse)
> +	 * slope = (FACTOR2 - FACTOR1 * n1) / FACTOR0
> +	 * (Nmeas - n1) / (Tmeas - t1) = slope
> +	 * We want to reduce this down to the minimum computation necessary
> +	 * for each temperature read.  Also, we want Tmeas in millicelsius
> +	 * and we don't want to lose precision from integer division. So...
> +	 * Tmeas = (Nmeas - n1) / slope + t1
> +	 * milli_Tmeas = 1000 * (Nmeas - n1) / slope + 1000 * t1
> +	 * milli_Tmeas = -1000 * (n1 - Nmeas) / slope + 1000 * t1
> +	 * Let constant c1 = (-1000 / slope)
> +	 * milli_Tmeas = (n1 - Nmeas) * c1 + 1000 * t1
> +	 * Let constant c2 = n1 *c1 + 1000 * t1
> +	 * milli_Tmeas = c2 - Nmeas * c1
> +	 */
> +	temp64 = FACTOR0;
> +	temp64 *= 1000;
> +	do_div(temp64, FACTOR1 * n1 - FACTOR2);
> +	c1 = temp64;
> +	c2 = n1 * c1 + 1000 * t1;
> +
> +	/*
> +	 * now we only use single measure, every time we read
> +	 * the temperature, we will power on/down anadig thermal
> +	 * module
> +	 */
> +	writel(TEMPSENSE0_POWER_DOWN, &anatop->tempsense0_clr);
> +	writel(MISC0_REFTOP_SELBIASOFF, &anatop->ana_misc0_set);
> +
> +	/* setup measure freq */
> +	reg = readl(&anatop->tempsense1);
> +	reg &= ~TEMPSENSE1_MEASURE_FREQ;
> +	reg |= MEASURE_FREQ;
> +	writel(reg, &anatop->tempsense1);
> +
> +	/* start the measurement process */
> +	writel(TEMPSENSE0_MEASURE_TEMP, &anatop->tempsense0_clr);
> +	writel(TEMPSENSE0_FINISHED, &anatop->tempsense0_clr);
> +	writel(TEMPSENSE0_MEASURE_TEMP, &anatop->tempsense0_set);
> +
> +	/* make sure that the latest temp is valid */
> +	while ((readl(&anatop->tempsense0) &
> +		TEMPSENSE0_FINISHED) == 0)
> +		udelay(10000);
> +
> +	/* read temperature count */
> +	reg = readl(&anatop->tempsense0);
> +	n_meas = (reg & TEMPSENSE0_TEMP_CNT_MASK)
> +		>> TEMPSENSE0_TEMP_CNT_SHIFT;
> +	writel(TEMPSENSE0_FINISHED, &anatop->tempsense0_clr);
> +
> +	/* milli_Tmeas = c2 - Nmeas * c1 */
> +	temperature = (c2 - n_meas * c1)/1000;
> +
> +	/* power down anatop thermal sensor */
> +	writel(TEMPSENSE0_POWER_DOWN, &anatop->tempsense0_set);
> +	writel(MISC0_REFTOP_SELBIASOFF, &anatop->ana_misc0_clr);
> +
> +	return temperature;
> +}
> +
> +int imx_thermal_get_temp(struct udevice *dev, int *temp)
> +{
> +	int cpu_tmp = 0;
> +
> +	cpu_tmp = read_cpu_temperature(dev);
> +	while (cpu_tmp > TEMPERATURE_MIN && cpu_tmp < TEMPERATURE_MAX) {
> +		if (cpu_tmp >= TEMPERATURE_HOT) {
> +			printf("CPU Temperature is %d C, too hot to boot, waiting...\n",
> +			       cpu_tmp);
> +			udelay(5000000);
> +			cpu_tmp = read_cpu_temperature(dev);
> +		} else {
> +			break;
> +		}
> +	}
> +
> +	*temp = cpu_tmp;
> +
> +	return 0;
> +}
> +
> +static const struct dm_thermal_ops imx_thermal_ops = {
> +	.get_temp	= imx_thermal_get_temp,
> +};
> +
> +static int imx_thermal_probe(struct udevice *dev)
> +{
> +	unsigned int fuse = ~0;
> +
> +	const struct imx_thermal_plat *pdata = dev_get_platdata(dev);
> +	unsigned int *priv = dev_get_priv(dev);
> +
> +	/* Read Temperature calibration data fuse */
> +	fuse_read(pdata->fuse_bank, pdata->fuse_word, &fuse);
> +
> +	/* Check for valid fuse */
> +	if (fuse == 0 || fuse == ~0) {
> +		printf("CPU:   Thermal invalid data, fuse: 0x%x\n", fuse);
> +		return -EPERM;
> +	} else {
> +		printf("CPU:   Thermal calibration data: 0x%x\n", fuse);
> +	}
> +
> +	*priv = fuse;
> +
> +	enable_thermal_clk();
> +
> +	return 0;
> +}
> +
> +U_BOOT_DRIVER(imx_thermal) = {
> +	.name	= "imx_thermal",
> +	.id	= UCLASS_THERMAL,
> +	.ops	= &imx_thermal_ops,
> +	.probe	= imx_thermal_probe,
> +	.priv_auto_alloc_size = sizeof(unsigned int),
> +	.flags  = DM_FLAG_PRE_RELOC,
> +};
> diff --git a/drivers/thermal/thermal-uclass.c b/drivers/thermal/thermal-uclass.c
> new file mode 100644
> index 0000000..3bee1a7
> --- /dev/null
> +++ b/drivers/thermal/thermal-uclass.c
> @@ -0,0 +1,30 @@
> +/*
> + * (C) Copyright 2014 Freescale Semiconductor, Inc
> + *
> + * SPDX-License-Identifier:	GPL-2.0+
> + */
> +
> +#include <common.h>
> +#include <dm.h>
> +#include <thermal.h>
> +#include <errno.h>
> +#include <fdtdec.h>
> +#include <malloc.h>
> +#include <asm/io.h>
> +#include <linux/list.h>
> +
> +
> +int thermal_get_temp(struct udevice *dev, int *temp)
> +{
> +	const struct dm_thermal_ops *ops = device_get_ops(dev);
> +
> +	if (!ops->get_temp)
> +		return -ENOSYS;
> +
> +	return ops->get_temp(dev, temp);
> +}
> +
> +UCLASS_DRIVER(thermal) = {
> +	.id		= UCLASS_THERMAL,
> +	.name		= "thermal",
> +};
> diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
> index a8944c9..202f59b 100644
> --- a/include/dm/uclass-id.h
> +++ b/include/dm/uclass-id.h
> @@ -28,6 +28,7 @@ enum uclass_id {
>  	UCLASS_SPI_GENERIC,	/* Generic SPI flash target */
>  	UCLASS_SPI_FLASH,	/* SPI flash */
>  	UCLASS_CROS_EC,	/* Chrome OS EC */
> +	UCLASS_THERMAL,		/* Thermal sensor */
>  
>  	UCLASS_COUNT,
>  	UCLASS_INVALID = -1,
> diff --git a/include/imx_thermal.h b/include/imx_thermal.h
> new file mode 100644
> index 0000000..be13652
> --- /dev/null
> +++ b/include/imx_thermal.h
> @@ -0,0 +1,17 @@
> +/*
> + *
> + * (C) Copyright 2014 Freescale Semiconductor, Inc
> + *
> + * SPDX-License-Identifier:	GPL-2.0+
> + */
> +
> +#ifndef _IMX_THERMAL_H_
> +#define _IMX_THERMAL_H_
> +
> +struct imx_thermal_plat {
> +	void *regs;
> +	int fuse_bank;
> +	int fuse_word;
> +};
> +
> +#endif	/* _IMX_THERMAL_H_ */
> diff --git a/include/thermal.h b/include/thermal.h
> new file mode 100644
> index 0000000..80b549b
> --- /dev/null
> +++ b/include/thermal.h
> @@ -0,0 +1,42 @@
> +/*
> + *
> + * (C) Copyright 2014 Freescale Semiconductor, Inc
> + *
> + * SPDX-License-Identifier:	GPL-2.0+
> + */
> +
> +#ifndef _THERMAL_H_
> +#define _THERMAL_H_
> +
> +#include <dm.h>
> +
> +int thermal_get_temp(struct udevice *dev, int *temp);
> +
> +/**
> + * struct struct dm_thermal_ops - Driver model Thermal operations
> + *
> + * The uclass interface is implemented by all Thermal devices which use
> + * driver model.
> + */
> +struct dm_thermal_ops {
> +	/**
> +	 * Get the current temperature
> +	 *
> +	 * The device provided is the slave device. It's parent controller
> +	 * will be used to provide the communication.
> +	 *
> +	 * This must be called before doing any transfers with a Thermal slave. It
> +	 * will enable and initialize any Thermal hardware as necessary, and make
> +	 * sure that the SCK line is in the correct idle state. It is not
> +	 * allowed to claim the same bus for several slaves without releasing
> +	 * the bus in between.
> +	 *
> +	 * @dev:	The Thermal device
> +	 *
> +	 * Returns: 0 if the bus was claimed successfully, or a negative value
> +	 * if it wasn't.
> +	 */
> +	int (*get_temp)(struct udevice *dev, int *temp);
> +};
> +
> +#endif	/* _THERMAL_H_ */
> 

Fine with me.

Acked-by: Stefano Babic <sbabic@denx.de>

Best regards,
Stefano Babic

-- 
=====================================================================
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-53 Fax: +49-8142-66989-80 Email: sbabic at denx.de
=====================================================================