DM: thermal: Add imx thermal DM driver

Add a new thermal uclass for thermal sensor and implement the imx
thermal driver basing on this uclass.

Signed-off-by: Ye.Li <B37916@freescale.com>
Acked-by: Stefano Babic <sbabic@denx.de>

diff --git a/drivers/Makefile b/drivers/Makefile
index 33227c8bd6de003d170962e7f7778ed1b091c460..7683c6139ffbf1eefe652a28764c0f168a271c95 100644 (file)
--- 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 (file)
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 (file)
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 (file)
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 a8944c97d03a9cfc9162a8c6289b21515862386b..202f59b505d34848a250afff2ebc4b4c4f25c840 100644 (file)
--- 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 (file)
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 (file)
index 0000000..5d6101b
--- /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_ */