[PATCHv3 1/1] ti-soc-thermal: implement omap3 support

Eduardo Valentin
2015-09-10T04:58:16Z

From: Pavel Machek <pavel@ucw.cz>

This adds support for OMAP3 chips to ti-soc-thermal. As requested by
TI people, it is marked unreliable and warning is printed.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-omap@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
---
.../devicetree/bindings/thermal/ti_soc_thermal.txt | 7 ++
drivers/thermal/ti-soc-thermal/Kconfig | 15 +++
drivers/thermal/ti-soc-thermal/Makefile | 1 +
.../thermal/ti-soc-thermal/omap3-thermal-data.c | 103 +++++++++++++++++++++
drivers/thermal/ti-soc-thermal/ti-bandgap.c | 10 ++
drivers/thermal/ti-soc-thermal/ti-bandgap.h | 9 ++
6 files changed, 145 insertions(+)
create mode 100644 drivers/thermal/ti-soc-thermal/omap3-thermal-data.c
---

Just not leave Pavels work behind, I took his patch and amended a couple
of things:
(1) added the omap3 DT example
(2) improved the dev_warn message
(3) improved the code documentation

diff --git a/Documentation/devicetree/bindings/thermal/ti_soc_thermal.txt b/Documentation/devicetree/bindings/thermal/ti_soc_thermal.txt
index 0c9222d..d9a1b54 100644
--- a/Documentation/devicetree/bindings/thermal/ti_soc_thermal.txt
+++ b/Documentation/devicetree/bindings/thermal/ti_soc_thermal.txt
@@ -10,6 +10,7 @@ to the silicon temperature.

Required properties:
- compatible : Should be:
+ - "ti,omap34xx-bandgap" : for OMAP34xx bandgap
- "ti,omap4430-bandgap" : for OMAP4430 bandgap
- "ti,omap4460-bandgap" : for OMAP4460 bandgap
- "ti,omap4470-bandgap" : for OMAP4470 bandgap
@@ -25,6 +26,12 @@ to each bandgap version, because the mapping may change from
soc to soc, apart of depending on available features.

Example:
+OMAP34xx:
+bandgap {
+ reg = <0x48002524 0x4>;
+ compatible = "ti,omap34xx-bandgap";
+};
+
OMAP4430:
bandgap {
reg = <0x4a002260 0x4 0x4a00232C 0x4>;
diff --git a/drivers/thermal/ti-soc-thermal/Kconfig b/drivers/thermal/ti-soc-thermal/Kconfig
index cb6686f..ea8283f 100644
--- a/drivers/thermal/ti-soc-thermal/Kconfig
+++ b/drivers/thermal/ti-soc-thermal/Kconfig
@@ -19,6 +19,21 @@ config TI_THERMAL
This includes trip points definitions, extrapolation rules and
CPU cooling device bindings.

+config OMAP3_THERMAL
+ bool "Texas Instruments OMAP3 thermal support"
+ depends on TI_SOC_THERMAL
+ depends on ARCH_OMAP3 || COMPILE_TEST
+ help
+ If you say yes here you get thermal support for the Texas Instruments
+ OMAP3 SoC family. The current chips supported are:
+ - OMAP3430
+
+ OMAP3 chips normally don't need thermal management, and sensors in
+ this generation are not accurate, nor they are very close to
+ the important hotspots.
+
+ Say 'N' here.
+
config OMAP4_THERMAL
bool "Texas Instruments OMAP4 thermal support"
depends on TI_SOC_THERMAL
diff --git a/drivers/thermal/ti-soc-thermal/Makefile b/drivers/thermal/ti-soc-thermal/Makefile
index 1226b24..0f89bdf 100644
--- a/drivers/thermal/ti-soc-thermal/Makefile
+++ b/drivers/thermal/ti-soc-thermal/Makefile
@@ -2,5 +2,6 @@ obj-$(CONFIG_TI_SOC_THERMAL) += ti-soc-thermal.o
ti-soc-thermal-y := ti-bandgap.o
ti-soc-thermal-$(CONFIG_TI_THERMAL) += ti-thermal-common.o
ti-soc-thermal-$(CONFIG_DRA752_THERMAL) += dra752-thermal-data.o
+ti-soc-thermal-$(CONFIG_OMAP3_THERMAL) += omap3-thermal-data.o
ti-soc-thermal-$(CONFIG_OMAP4_THERMAL) += omap4-thermal-data.o
ti-soc-thermal-$(CONFIG_OMAP5_THERMAL) += omap5-thermal-data.o
diff --git a/drivers/thermal/ti-soc-thermal/omap3-thermal-data.c b/drivers/thermal/ti-soc-thermal/omap3-thermal-data.c
new file mode 100644
index 0000000..8470225
--- /dev/null
+++ b/drivers/thermal/ti-soc-thermal/omap3-thermal-data.c
@@ -0,0 +1,103 @@
+/*
+ * OMAP3 thermal driver.
+ *
+ * Copyright (C) 2011-2012 Texas Instruments Inc.
+ * Copyright (C) 2014 Pavel Machek <pavel@ucw.cz>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Note
+ * http://www.ti.com/lit/er/sprz278f/sprz278f.pdf "Advisory
+ * 3.1.1.186 MMC OCP Clock Not Gated When Thermal Sensor Is Used"
+ *
+ * Also TI says:
+ * Just be careful when you try to make thermal policy like decisions
+ * based on this sensor. Placement of the sensor w.r.t the actual logic
+ * generating heat has to be a factor as well. If you are just looking
+ * for an approximation temperature (thermometerish kind), you might be
+ * ok with this. I am not sure we'd find any TI data around this.. just a
+ * heads up.
+ */
+
+#include "ti-thermal.h"
+#include "ti-bandgap.h"
+
+/*
+ * OMAP34XX has one instance of thermal sensor for MPU
+ * need to describe the individual bit fields
+ */
+static struct temp_sensor_registers
+omap34xx_mpu_temp_sensor_registers = {
+ .temp_sensor_ctrl = 0,
+ .bgap_soc_mask = BIT(8),
+ .bgap_eocz_mask = BIT(7),
+ .bgap_dtemp_mask = 0x7f,
+
+ .bgap_mode_ctrl = 0,
+ .mode_ctrl_mask = BIT(9),
+};
+
+/* Thresholds and limits for OMAP34XX MPU temperature sensor */
+static struct temp_sensor_data omap34xx_mpu_temp_sensor_data = {
+ .min_freq = 32768,
+ .max_freq = 32768,
+ .max_temp = 125000,
+ .min_temp = -40000,
+ .hyst_val = 5000,
+};
+
+/*
+ * Temperature values in milli degree celsius
+ */
+static const int
+omap34xx_adc_to_temp[128] = {
+ -40000, -40000, -40000, -40000, -40000, -39000, -38000, -36000,
+ -34000, -32000, -31000, -29000, -28000, -26000, -25000, -24000,
+ -22000, -21000, -19000, -18000, -17000, -15000, -14000, -12000,
+ -11000, -9000, -8000, -7000, -5000, -4000, -2000, -1000, 0000,
+ 1000, 3000, 4000, 5000, 7000, 8000, 10000, 11000, 13000, 14000,
+ 15000, 17000, 18000, 20000, 21000, 22000, 24000, 25000, 27000,
+ 28000, 30000, 31000, 32000, 34000, 35000, 37000, 38000, 39000,
+ 41000, 42000, 44000, 45000, 47000, 48000, 49000, 51000, 52000,
+ 53000, 55000, 56000, 58000, 59000, 60000, 62000, 63000, 65000,
+ 66000, 67000, 69000, 70000, 72000, 73000, 74000, 76000, 77000,
+ 79000, 80000, 81000, 83000, 84000, 85000, 87000, 88000, 89000,
+ 91000, 92000, 94000, 95000, 96000, 98000, 99000, 100000,
+ 102000, 103000, 105000, 106000, 107000, 109000, 110000, 111000,
+ 113000, 114000, 116000, 117000, 118000, 120000, 121000, 122000,
+ 124000, 124000, 125000, 125000, 125000, 125000, 125000
+};
+
+/* OMAP34XX data */
+const struct ti_bandgap_data omap34xx_data = {
+ .features = TI_BANDGAP_FEATURE_CLK_CTRL | TI_BANDGAP_FEATURE_UNRELIABLE,
+ .fclock_name = "ts_fck",
+ .div_ck_name = "ts_fck",
+ .conv_table = omap34xx_adc_to_temp,
+ .adc_start_val = 0,
+ .adc_end_val = 127,
+ .expose_sensor = ti_thermal_expose_sensor,
+ .remove_sensor = ti_thermal_remove_sensor,
+
+ .sensors = {
+ {
+ .registers = &omap34xx_mpu_temp_sensor_registers,
+ .ts_data = &omap34xx_mpu_temp_sensor_data,
+ .domain = "cpu",
+ .slope = 0,
+ .constant = 20000,
+ .slope_pcb = 0,
+ .constant_pcb = 20000,
+ .register_cooling = NULL,
+ .unregister_cooling = NULL,
+ },
+ },
+ .sensor_count = 1,
+};
diff --git a/drivers/thermal/ti-soc-thermal/ti-bandgap.c b/drivers/thermal/ti-soc-thermal/ti-bandgap.c
index 10c47c0..9f9ed72 100644
--- a/drivers/thermal/ti-soc-thermal/ti-bandgap.c
+++ b/drivers/thermal/ti-soc-thermal/ti-bandgap.c
@@ -1274,6 +1274,10 @@ int ti_bandgap_probe(struct platform_device *pdev)
}
bgp->dev = &pdev->dev;

+ if (TI_BANDGAP_HAS(bgp, UNRELIABLE))
+ dev_warn(&pdev->dev,
+ "This OMAP thermal sensor is unreliable. You've been warned\n");
+
if (TI_BANDGAP_HAS(bgp, TSHUT)) {
ret = ti_bandgap_tshut_init(bgp, pdev);
if (ret) {
@@ -1579,6 +1583,12 @@ static SIMPLE_DEV_PM_OPS(ti_bandgap_dev_pm_ops, ti_bandgap_suspend,
#endif

static const struct of_device_id of_ti_bandgap_match[] = {
+#ifdef CONFIG_OMAP3_THERMAL
+ {
+ .compatible = "ti,omap34xx-bandgap",
+ .data = (void *)&omap34xx_data,
+ },
+#endif
#ifdef CONFIG_OMAP4_THERMAL
{
.compatible = "ti,omap4430-bandgap",
diff --git a/drivers/thermal/ti-soc-thermal/ti-bandgap.h b/drivers/thermal/ti-soc-thermal/ti-bandgap.h
index 0c52f7a..045f642 100644
--- a/drivers/thermal/ti-soc-thermal/ti-bandgap.h
+++ b/drivers/thermal/ti-soc-thermal/ti-bandgap.h
@@ -322,6 +322,8 @@ struct ti_temp_sensor {
* has Errata 814
* TI_BANDGAP_FEATURE_ERRATA_813 - used to workaorund when the bandgap device
* has Errata 813
+ * TI_BANDGAP_FEATURE_UNRELIABLE - used when the sensor readings are too
+ * inaccurate.
* TI_BANDGAP_HAS(b, f) - macro to check if a bandgap device is capable of a
* specific feature (above) or not. Return non-zero, if yes.
*/
@@ -337,6 +339,7 @@ struct ti_temp_sensor {
#define TI_BANDGAP_FEATURE_HISTORY_BUFFER BIT(9)
#define TI_BANDGAP_FEATURE_ERRATA_814 BIT(10)
#define TI_BANDGAP_FEATURE_ERRATA_813 BIT(11)
+#define TI_BANDGAP_FEATURE_UNRELIABLE BIT(12)
#define TI_BANDGAP_HAS(b, f) \
((b)->conf->features & TI_BANDGAP_FEATURE_ ## f)

@@ -390,6 +393,12 @@ int ti_bandgap_set_sensor_data(struct ti_bandgap *bgp, int id, void *data);
void *ti_bandgap_get_sensor_data(struct ti_bandgap *bgp, int id);
int ti_bandgap_get_trend(struct ti_bandgap *bgp, int id, int *trend);

+#ifdef CONFIG_OMAP3_THERMAL
+extern const struct ti_bandgap_data omap34xx_data;
+#else
+#define omap34xx_data NULL
+#endif
+
#ifdef CONFIG_OMAP4_THERMAL
extern const struct ti_bandgap_data omap4430_data;
extern const struct ti_bandgap_data omap4460_data;
--
2.5.0