[PATCH v5 4/4] thermal: Add Tegra SOCTHERM thermal management driver

From: Mikko Perttunen
Date: Thu Aug 21 2014 - 06:18:41 EST


This adds support for the Tegra SOCTHERM thermal sensing and management
system found in the Tegra124 system-on-chip. This initial driver supports
temperature polling for four thermal zones.

Signed-off-by: Mikko Perttunen <mperttunen@xxxxxxxxxx>
---
v5:
- changed tsample_ate to 480
- constified structs
- added missing --i
- read shifted_ft from TSENSOR8 fuse
- use precise divison function when calculating
calibration values

drivers/thermal/Kconfig | 10 +
drivers/thermal/Makefile | 1 +
drivers/thermal/tegra_soctherm.c | 471 +++++++++++++++++++++++++++++++++++++++
3 files changed, 482 insertions(+)
create mode 100644 drivers/thermal/tegra_soctherm.c

diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index 693208e..fd9d049 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -175,6 +175,16 @@ config ARMADA_THERMAL
Enable this option if you want to have support for thermal management
controller present in Armada 370 and Armada XP SoC.

+config TEGRA_SOCTHERM
+ tristate "Tegra SOCTHERM thermal management"
+ depends on ARCH_TEGRA
+ help
+ Enable this option for integrated thermal management support on NVIDIA
+ Tegra124 systems-on-chip. The driver supports four thermal zones
+ (CPU, GPU, MEM, PLLX). Cooling devices can be bound to the thermal
+ zones to manage temperatures. This option is also required for the
+ emergency thermal reset (thermtrip) feature to function.
+
config DB8500_CPUFREQ_COOLING
tristate "DB8500 cpufreq cooling"
depends on ARCH_U8500
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index 31e232f..f0b94d5 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -33,3 +33,4 @@ obj-$(CONFIG_INTEL_SOC_DTS_THERMAL) += intel_soc_dts_thermal.o
obj-$(CONFIG_TI_SOC_THERMAL) += ti-soc-thermal/
obj-$(CONFIG_ACPI_INT3403_THERMAL) += int3403_thermal.o
obj-$(CONFIG_ST_THERMAL) += st/
+obj-$(CONFIG_TEGRA_SOCTHERM) += tegra_soctherm.o
diff --git a/drivers/thermal/tegra_soctherm.c b/drivers/thermal/tegra_soctherm.c
new file mode 100644
index 0000000..3742e24
--- /dev/null
+++ b/drivers/thermal/tegra_soctherm.c
@@ -0,0 +1,471 @@
+/*
+ * drivers/thermal/tegra_soctherm.c
+ *
+ * Copyright (c) 2014, NVIDIA CORPORATION. All rights reserved.
+ *
+ * Author:
+ * Mikko Perttunen <mperttunen@xxxxxxxxxx>
+ *
+ * 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.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include <linux/thermal.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/bitops.h>
+#include <soc/tegra/fuse.h>
+
+#define SENSOR_CONFIG0 0
+#define SENSOR_CONFIG0_STOP BIT(0)
+#define SENSOR_CONFIG0_TALL_SHIFT 8
+#define SENSOR_CONFIG0_TCALC_OVER BIT(4)
+#define SENSOR_CONFIG0_OVER BIT(3)
+#define SENSOR_CONFIG0_CPTR_OVER BIT(2)
+#define SENSOR_CONFIG1 4
+#define SENSOR_CONFIG1_TSAMPLE_SHIFT 0
+#define SENSOR_CONFIG1_TIDDQ_EN_SHIFT 15
+#define SENSOR_CONFIG1_TEN_COUNT_SHIFT 24
+#define SENSOR_CONFIG1_TEMP_ENABLE BIT(31)
+#define SENSOR_CONFIG2 8
+#define SENSOR_CONFIG2_THERMA_SHIFT 16
+#define SENSOR_CONFIG2_THERMB_SHIFT 0
+
+#define SENSOR_PDIV 0x1c0
+#define SENSOR_PDIV_T124 0x8888
+#define SENSOR_HOTSPOT_OFF 0x1c4
+#define SENSOR_HOTSPOT_OFF_T124 0x00060600
+#define SENSOR_TEMP1 0x1c8
+#define SENSOR_TEMP2 0x1cc
+
+#define SENSOR_TEMP_MASK 0xffff
+#define READBACK_VALUE_MASK 0xff00
+#define READBACK_VALUE_SHIFT 8
+#define READBACK_ADD_HALF BIT(7)
+#define READBACK_NEGATE BIT(1)
+
+#define FUSE_TSENSOR8_CALIB 0x180
+#define FUSE_SPARE_REALIGNMENT_REG_0 0x1fc
+
+#define FUSE_TSENSOR_CALIB_CP_TS_BASE_MASK 0x1fff
+#define FUSE_TSENSOR_CALIB_FT_TS_BASE_MASK (0x1fff << 13)
+#define FUSE_TSENSOR_CALIB_FT_TS_BASE_SHIFT 13
+
+#define FUSE_TSENSOR8_CALIB_CP_TS_BASE_MASK 0x3ff
+#define FUSE_TSENSOR8_CALIB_FT_TS_BASE_MASK (0x7ff << 10)
+#define FUSE_TSENSOR8_CALIB_FT_TS_BASE_SHIFT 10
+
+#define FUSE_SPARE_REALIGNMENT_REG_SHIFT_CP_MASK 0x3f
+#define FUSE_SPARE_REALIGNMENT_REG_SHIFT_FT_MASK (0x1f << 21)
+#define FUSE_SPARE_REALIGNMENT_REG_SHIFT_FT_SHIFT 21
+
+#define NOMINAL_CALIB_FT_T124 105
+#define NOMINAL_CALIB_CP_T124 25
+
+struct tegra_tsensor_configuration {
+ u32 tall, tsample, tiddq_en, ten_count;
+ u32 pdiv, tsample_ate, pdiv_ate;
+};
+
+struct tegra_tsensor {
+ u32 base;
+ u32 calib_fuse_offset;
+ /* Correction values used to modify values read from calibration fuses */
+ s32 fuse_corr_alpha, fuse_corr_beta;
+};
+
+struct tegra_thermctl_zone {
+ void __iomem *temp_reg;
+ int temp_shift;
+};
+
+static const struct tegra_tsensor_configuration t124_tsensor_config = {
+ .tall = 16300,
+ .tsample = 120,
+ .tiddq_en = 1,
+ .ten_count = 1,
+ .pdiv = 8,
+ .tsample_ate = 480,
+ .pdiv_ate = 8
+};
+
+static const struct tegra_tsensor t124_tsensors[] = {
+ {
+ .base = 0xc0,
+ .calib_fuse_offset = 0x098,
+ .fuse_corr_alpha = 1135400,
+ .fuse_corr_beta = -6266900,
+ },
+ {
+ .base = 0xe0,
+ .calib_fuse_offset = 0x084,
+ .fuse_corr_alpha = 1122220,
+ .fuse_corr_beta = -5700700,
+ },
+ {
+ .base = 0x100,
+ .calib_fuse_offset = 0x088,
+ .fuse_corr_alpha = 1127000,
+ .fuse_corr_beta = -6768200,
+ },
+ {
+ .base = 0x120,
+ .calib_fuse_offset = 0x12c,
+ .fuse_corr_alpha = 1110900,
+ .fuse_corr_beta = -6232000,
+ },
+ {
+ .base = 0x140,
+ .calib_fuse_offset = 0x158,
+ .fuse_corr_alpha = 1122300,
+ .fuse_corr_beta = -5936400,
+ },
+ {
+ .base = 0x160,
+ .calib_fuse_offset = 0x15c,
+ .fuse_corr_alpha = 1145700,
+ .fuse_corr_beta = -7124600,
+ },
+ {
+ .base = 0x180,
+ .calib_fuse_offset = 0x154,
+ .fuse_corr_alpha = 1120100,
+ .fuse_corr_beta = -6000500,
+ },
+ {
+ .base = 0x1a0,
+ .calib_fuse_offset = 0x160,
+ .fuse_corr_alpha = 1106500,
+ .fuse_corr_beta = -6729300,
+ },
+};
+
+struct tegra_soctherm {
+ struct reset_control *reset;
+ struct clk *clock_tsensor;
+ struct clk *clock_soctherm;
+ void __iomem *regs;
+
+ struct thermal_zone_device *thermctl_tzs[4];
+};
+
+struct tsensor_shared_calibration {
+ u32 base_cp, base_ft;
+ u32 actual_temp_cp, actual_temp_ft;
+};
+
+static int calculate_shared_calibration(struct tsensor_shared_calibration *r)
+{
+ u32 val;
+ u32 shifted_cp, shifted_ft;
+ int err;
+
+ err = tegra_fuse_readl(FUSE_TSENSOR8_CALIB, &val);
+ if (err)
+ return err;
+ r->base_cp = val & FUSE_TSENSOR8_CALIB_CP_TS_BASE_MASK;
+ r->base_ft = (val & FUSE_TSENSOR8_CALIB_FT_TS_BASE_MASK)
+ >> FUSE_TSENSOR8_CALIB_FT_TS_BASE_SHIFT;
+ val = ((val & FUSE_SPARE_REALIGNMENT_REG_SHIFT_FT_MASK)
+ >> FUSE_SPARE_REALIGNMENT_REG_SHIFT_FT_SHIFT);
+ shifted_ft = sign_extend32(val, 4);
+
+ err = tegra_fuse_readl(FUSE_SPARE_REALIGNMENT_REG_0, &val);
+ if (err)
+ return err;
+ shifted_cp = sign_extend32(val, 5);
+
+ r->actual_temp_cp = 2 * NOMINAL_CALIB_CP_T124 + shifted_cp;
+ r->actual_temp_ft = 2 * NOMINAL_CALIB_FT_T124 + shifted_ft;
+
+ return 0;
+}
+
+static s64 div64_s64_precise(s64 a, s64 b)
+{
+ s64 r, al;
+
+ /* Scale up for increased precision division */
+ al = a << 16;
+
+ r = div64_s64(al * 2 + 1, 2 * b);
+ return r >> 16;
+}
+
+static int calculate_tsensor_calibration(
+ const struct tegra_tsensor *sensor,
+ struct tsensor_shared_calibration shared,
+ u32 *calib
+)
+{
+ u32 val;
+ s32 actual_tsensor_ft, actual_tsensor_cp;
+ s32 delta_sens, delta_temp;
+ s32 mult, div;
+ s16 therma, thermb;
+ int err;
+
+ err = tegra_fuse_readl(sensor->calib_fuse_offset, &val);
+ if (err)
+ return err;
+
+ actual_tsensor_cp = (shared.base_cp * 64) + sign_extend32(val, 12);
+ val = (val & FUSE_TSENSOR_CALIB_FT_TS_BASE_MASK)
+ >> FUSE_TSENSOR_CALIB_FT_TS_BASE_SHIFT;
+ actual_tsensor_ft = (shared.base_ft * 32) + sign_extend32(val, 12);
+
+ delta_sens = actual_tsensor_ft - actual_tsensor_cp;
+ delta_temp = shared.actual_temp_ft - shared.actual_temp_cp;
+
+ mult = t124_tsensor_config.pdiv * t124_tsensor_config.tsample_ate;
+ div = t124_tsensor_config.tsample * t124_tsensor_config.pdiv_ate;
+
+ therma = div64_s64_precise((s64) delta_temp * (1LL << 13) * mult,
+ (s64) delta_sens * div);
+ thermb = div64_s64_precise(
+ ((s64) actual_tsensor_ft * shared.actual_temp_cp) -
+ ((s64) actual_tsensor_cp * shared.actual_temp_ft),
+ (s64) delta_sens);
+
+ therma = div64_s64_precise((s64) therma * sensor->fuse_corr_alpha,
+ (s64) 1000000LL);
+ thermb = div64_s64_precise((s64) thermb * sensor->fuse_corr_alpha +
+ sensor->fuse_corr_beta,
+ (s64) 1000000LL);
+
+ *calib = ((u16)(therma) << SENSOR_CONFIG2_THERMA_SHIFT) |
+ ((u16)thermb << SENSOR_CONFIG2_THERMB_SHIFT);
+
+ return 0;
+}
+
+static int enable_tsensor(struct tegra_soctherm *tegra,
+ const struct tegra_tsensor *sensor,
+ struct tsensor_shared_calibration shared)
+{
+ void * __iomem base = tegra->regs + sensor->base;
+ unsigned int val;
+ u32 calib;
+ int err;
+
+ err = calculate_tsensor_calibration(sensor, shared, &calib);
+ if (err)
+ return err;
+
+ val = 0;
+ val |= t124_tsensor_config.tall << SENSOR_CONFIG0_TALL_SHIFT;
+ writel(val, base + SENSOR_CONFIG0);
+
+ val = 0;
+ val |= (t124_tsensor_config.tsample - 1) <<
+ SENSOR_CONFIG1_TSAMPLE_SHIFT;
+ val |= t124_tsensor_config.tiddq_en << SENSOR_CONFIG1_TIDDQ_EN_SHIFT;
+ val |= t124_tsensor_config.ten_count << SENSOR_CONFIG1_TEN_COUNT_SHIFT;
+ val |= SENSOR_CONFIG1_TEMP_ENABLE;
+ writel(val, base + SENSOR_CONFIG1);
+
+ writel(calib, base + SENSOR_CONFIG2);
+
+ return 0;
+}
+
+/* Translate from soctherm readback format to millicelsius.
+ * The soctherm readback format in bits is as follows:
+ * TTTTTTTT H______N
+ * where T's contain the temperature in Celsius,
+ * H denotes an addition of 0.5 Celsius and N denotes negation
+ * of the final value.
+ */
+static inline long translate_temp(u16 val)
+{
+ long t;
+
+ t = ((val & READBACK_VALUE_MASK) >> READBACK_VALUE_SHIFT) * 1000;
+ if (val & READBACK_ADD_HALF)
+ t += 500;
+ if (val & READBACK_NEGATE)
+ t *= -1;
+
+ return t;
+}
+
+static int tegra_thermctl_get_temp(void *data, long *out_temp)
+{
+ struct tegra_thermctl_zone *zone = data;
+ u32 val;
+
+ val = (readl(zone->temp_reg) >> zone->temp_shift) & SENSOR_TEMP_MASK;
+ *out_temp = translate_temp(val);
+
+ return 0;
+}
+
+static const struct of_device_id tegra_soctherm_of_match[] = {
+ { .compatible = "nvidia,tegra124-soctherm" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, tegra_soctherm_of_match);
+
+static const int thermctl_temp_offsets[] = {
+ SENSOR_TEMP1, SENSOR_TEMP2, SENSOR_TEMP1, SENSOR_TEMP2
+};
+
+static const int thermctl_temp_shifts[] = {
+ 16, 16, 0, 0
+};
+
+static int tegra_soctherm_probe(struct platform_device *pdev)
+{
+ struct tegra_soctherm *tegra;
+ struct thermal_zone_device *tz;
+ struct tsensor_shared_calibration shared_calib;
+ int i;
+ int err = 0;
+
+ const struct tegra_tsensor *tsensors = t124_tsensors;
+
+ tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL);
+ if (!tegra)
+ return -ENOMEM;
+
+ tegra->regs = devm_ioremap_resource(&pdev->dev,
+ platform_get_resource(pdev, IORESOURCE_MEM, 0));
+ if (IS_ERR(tegra->regs)) {
+ dev_err(&pdev->dev, "can't get registers");
+ return PTR_ERR(tegra->regs);
+ }
+
+ tegra->reset = devm_reset_control_get(&pdev->dev, "soctherm");
+ if (IS_ERR(tegra->reset)) {
+ dev_err(&pdev->dev, "can't get soctherm reset\n");
+ return PTR_ERR(tegra->reset);
+ }
+
+ tegra->clock_tsensor = devm_clk_get(&pdev->dev, "tsensor");
+ if (IS_ERR(tegra->clock_tsensor)) {
+ dev_err(&pdev->dev, "can't get clock tsensor\n");
+ return PTR_ERR(tegra->clock_tsensor);
+ }
+
+ tegra->clock_soctherm = devm_clk_get(&pdev->dev, "soctherm");
+ if (IS_ERR(tegra->clock_soctherm)) {
+ dev_err(&pdev->dev, "can't get clock soctherm\n");
+ return PTR_ERR(tegra->clock_soctherm);
+ }
+
+ reset_control_assert(tegra->reset);
+
+ err = clk_prepare_enable(tegra->clock_soctherm);
+ if (err) {
+ reset_control_deassert(tegra->reset);
+ return err;
+ }
+
+ err = clk_prepare_enable(tegra->clock_tsensor);
+ if (err) {
+ clk_disable_unprepare(tegra->clock_soctherm);
+ reset_control_deassert(tegra->reset);
+ return err;
+ }
+
+ reset_control_deassert(tegra->reset);
+
+ /* Initialize raw sensors */
+
+ err = calculate_shared_calibration(&shared_calib);
+ if (err)
+ goto disable_clocks;
+
+ for (i = 0; i < ARRAY_SIZE(t124_tsensors); ++i) {
+ err = enable_tsensor(tegra, tsensors + i, shared_calib);
+ if (err)
+ goto disable_clocks;
+ }
+
+ writel(SENSOR_PDIV_T124, tegra->regs + SENSOR_PDIV);
+ writel(SENSOR_HOTSPOT_OFF_T124, tegra->regs + SENSOR_HOTSPOT_OFF);
+
+ /* Initialize thermctl sensors */
+
+ for (i = 0; i < ARRAY_SIZE(tegra->thermctl_tzs); ++i) {
+ struct tegra_thermctl_zone *zone =
+ devm_kzalloc(&pdev->dev, sizeof(*zone), GFP_KERNEL);
+ if (!zone) {
+ err = -ENOMEM;
+ --i;
+ goto unregister_tzs;
+ }
+
+ zone->temp_reg = tegra->regs + thermctl_temp_offsets[i];
+ zone->temp_shift = thermctl_temp_shifts[i];
+
+ tz = thermal_zone_of_sensor_register(
+ &pdev->dev, i, zone, tegra_thermctl_get_temp, NULL);
+ if (IS_ERR(tz)) {
+ err = PTR_ERR(tz);
+ dev_err(&pdev->dev, "failed to register sensor: %d\n",
+ err);
+ --i;
+ goto unregister_tzs;
+ }
+
+ tegra->thermctl_tzs[i] = tz;
+ }
+
+ return 0;
+
+unregister_tzs:
+ for (; i >= 0; i--)
+ thermal_zone_of_sensor_unregister(&pdev->dev,
+ tegra->thermctl_tzs[i]);
+
+disable_clocks:
+ clk_disable_unprepare(tegra->clock_tsensor);
+ clk_disable_unprepare(tegra->clock_soctherm);
+
+ return err;
+}
+
+static int tegra_soctherm_remove(struct platform_device *pdev)
+{
+ struct tegra_soctherm *tegra = platform_get_drvdata(pdev);
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(tegra->thermctl_tzs); ++i) {
+ thermal_zone_of_sensor_unregister(&pdev->dev,
+ tegra->thermctl_tzs[i]);
+ }
+
+ clk_disable_unprepare(tegra->clock_tsensor);
+ clk_disable_unprepare(tegra->clock_soctherm);
+
+ return 0;
+}
+
+static struct platform_driver tegra_soctherm_driver = {
+ .probe = tegra_soctherm_probe,
+ .remove = tegra_soctherm_remove,
+ .driver = {
+ .name = "tegra_soctherm",
+ .of_match_table = tegra_soctherm_of_match,
+ },
+};
+module_platform_driver(tegra_soctherm_driver);
+
+MODULE_AUTHOR("Mikko Perttunen <mperttunen@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Tegra SOCTHERM thermal management driver");
+MODULE_LICENSE("GPL v2");
--
1.8.1.5

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