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-rw-r--r--drivers/thermal/armada_thermal.c270
1 files changed, 269 insertions, 1 deletions
diff --git a/drivers/thermal/armada_thermal.c b/drivers/thermal/armada_thermal.c
index 4b36a3022849..df3054b0ae6b 100644
--- a/drivers/thermal/armada_thermal.c
+++ b/drivers/thermal/armada_thermal.c
@@ -26,6 +26,11 @@
#include <linux/iopoll.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
+#include <linux/interrupt.h>
+
+#include "thermal_core.h"
+
+#define TO_MCELSIUS(c) ((c) * 1000)
/* Thermal Manager Control and Status Register */
#define PMU_TDC0_SW_RST_MASK (0x1 << 1)
@@ -61,9 +66,13 @@
#define CONTROL1_TSEN_AVG_MASK 0x7
#define CONTROL1_EXT_TSEN_SW_RESET BIT(7)
#define CONTROL1_EXT_TSEN_HW_RESETn BIT(8)
+#define CONTROL1_TSEN_INT_EN BIT(25)
+#define CONTROL1_TSEN_SELECT_OFF 21
+#define CONTROL1_TSEN_SELECT_MASK 0x3
#define STATUS_POLL_PERIOD_US 1000
#define STATUS_POLL_TIMEOUT_US 100000
+#define OVERHEAT_INT_POLL_DELAY_MS 1000
struct armada_thermal_data;
@@ -75,7 +84,11 @@ struct armada_thermal_priv {
/* serialize temperature reads/updates */
struct mutex update_lock;
struct armada_thermal_data *data;
+ struct thermal_zone_device *overheat_sensor;
+ int interrupt_source;
int current_channel;
+ long current_threshold;
+ long current_hysteresis;
};
struct armada_thermal_data {
@@ -93,12 +106,20 @@ struct armada_thermal_data {
/* Register shift and mask to access the sensor temperature */
unsigned int temp_shift;
unsigned int temp_mask;
+ unsigned int thresh_shift;
+ unsigned int hyst_shift;
+ unsigned int hyst_mask;
u32 is_valid_bit;
/* Syscon access */
unsigned int syscon_control0_off;
unsigned int syscon_control1_off;
unsigned int syscon_status_off;
+ unsigned int dfx_irq_cause_off;
+ unsigned int dfx_irq_mask_off;
+ unsigned int dfx_overheat_irq;
+ unsigned int dfx_server_irq_mask_off;
+ unsigned int dfx_server_irq_en;
/* One sensor is in the thermal IC, the others are in the CPUs if any */
unsigned int cpu_nr;
@@ -272,6 +293,41 @@ static bool armada_is_valid(struct armada_thermal_priv *priv)
return reg & priv->data->is_valid_bit;
}
+static void armada_enable_overheat_interrupt(struct armada_thermal_priv *priv)
+{
+ struct armada_thermal_data *data = priv->data;
+ u32 reg;
+
+ /* Clear DFX temperature IRQ cause */
+ regmap_read(priv->syscon, data->dfx_irq_cause_off, &reg);
+
+ /* Enable DFX Temperature IRQ */
+ regmap_read(priv->syscon, data->dfx_irq_mask_off, &reg);
+ reg |= data->dfx_overheat_irq;
+ regmap_write(priv->syscon, data->dfx_irq_mask_off, reg);
+
+ /* Enable DFX server IRQ */
+ regmap_read(priv->syscon, data->dfx_server_irq_mask_off, &reg);
+ reg |= data->dfx_server_irq_en;
+ regmap_write(priv->syscon, data->dfx_server_irq_mask_off, reg);
+
+ /* Enable overheat interrupt */
+ regmap_read(priv->syscon, data->syscon_control1_off, &reg);
+ reg |= CONTROL1_TSEN_INT_EN;
+ regmap_write(priv->syscon, data->syscon_control1_off, reg);
+}
+
+static void __maybe_unused
+armada_disable_overheat_interrupt(struct armada_thermal_priv *priv)
+{
+ struct armada_thermal_data *data = priv->data;
+ u32 reg;
+
+ regmap_read(priv->syscon, data->syscon_control1_off, &reg);
+ reg &= ~CONTROL1_TSEN_INT_EN;
+ regmap_write(priv->syscon, data->syscon_control1_off, reg);
+}
+
/* There is currently no board with more than one sensor per channel */
static int armada_select_channel(struct armada_thermal_priv *priv, int channel)
{
@@ -388,6 +444,14 @@ static int armada_get_temp(void *_sensor, int *temp)
/* Do the actual reading */
ret = armada_read_sensor(priv, temp);
+ if (ret)
+ goto unlock_mutex;
+
+ /*
+ * Select back the interrupt source channel from which a potential
+ * critical trip point has been set.
+ */
+ ret = armada_select_channel(priv, priv->interrupt_source);
unlock_mutex:
mutex_unlock(&priv->update_lock);
@@ -399,6 +463,123 @@ static struct thermal_zone_of_device_ops of_ops = {
.get_temp = armada_get_temp,
};
+static unsigned int armada_mc_to_reg_temp(struct armada_thermal_data *data,
+ unsigned int temp_mc)
+{
+ s64 b = data->coef_b;
+ s64 m = data->coef_m;
+ s64 div = data->coef_div;
+ unsigned int sample;
+
+ if (data->inverted)
+ sample = div_s64(((temp_mc * div) + b), m);
+ else
+ sample = div_s64((b - (temp_mc * div)), m);
+
+ return sample & data->temp_mask;
+}
+
+/*
+ * The documentation states:
+ * high/low watermark = threshold +/- 0.4761 * 2^(hysteresis + 2)
+ * which is the mathematical derivation for:
+ * 0x0 <=> 1.9°C, 0x1 <=> 3.8°C, 0x2 <=> 7.6°C, 0x3 <=> 15.2°C
+ */
+static unsigned int hyst_levels_mc[] = {1900, 3800, 7600, 15200};
+
+static unsigned int armada_mc_to_reg_hyst(struct armada_thermal_data *data,
+ unsigned int hyst_mc)
+{
+ int i;
+
+ /*
+ * We will always take the smallest possible hysteresis to avoid risking
+ * the hardware integrity by enlarging the threshold by +8°C in the
+ * worst case.
+ */
+ for (i = ARRAY_SIZE(hyst_levels_mc) - 1; i > 0; i--)
+ if (hyst_mc >= hyst_levels_mc[i])
+ break;
+
+ return i & data->hyst_mask;
+}
+
+static void armada_set_overheat_thresholds(struct armada_thermal_priv *priv,
+ int thresh_mc, int hyst_mc)
+{
+ struct armada_thermal_data *data = priv->data;
+ unsigned int threshold = armada_mc_to_reg_temp(data, thresh_mc);
+ unsigned int hysteresis = armada_mc_to_reg_hyst(data, hyst_mc);
+ u32 ctrl1;
+
+ regmap_read(priv->syscon, data->syscon_control1_off, &ctrl1);
+
+ /* Set Threshold */
+ if (thresh_mc >= 0) {
+ ctrl1 &= ~(data->temp_mask << data->thresh_shift);
+ ctrl1 |= threshold << data->thresh_shift;
+ priv->current_threshold = thresh_mc;
+ }
+
+ /* Set Hysteresis */
+ if (hyst_mc >= 0) {
+ ctrl1 &= ~(data->hyst_mask << data->hyst_shift);
+ ctrl1 |= hysteresis << data->hyst_shift;
+ priv->current_hysteresis = hyst_mc;
+ }
+
+ regmap_write(priv->syscon, data->syscon_control1_off, ctrl1);
+}
+
+static irqreturn_t armada_overheat_isr(int irq, void *blob)
+{
+ /*
+ * Disable the IRQ and continue in thread context (thermal core
+ * notification and temperature monitoring).
+ */
+ disable_irq_nosync(irq);
+
+ return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t armada_overheat_isr_thread(int irq, void *blob)
+{
+ struct armada_thermal_priv *priv = blob;
+ int low_threshold = priv->current_threshold - priv->current_hysteresis;
+ int temperature;
+ u32 dummy;
+ int ret;
+
+ /* Notify the core in thread context */
+ thermal_zone_device_update(priv->overheat_sensor,
+ THERMAL_EVENT_UNSPECIFIED);
+
+ /*
+ * The overheat interrupt must be cleared by reading the DFX interrupt
+ * cause _after_ the temperature has fallen down to the low threshold.
+ * Otherwise future interrupts might not be served.
+ */
+ do {
+ msleep(OVERHEAT_INT_POLL_DELAY_MS);
+ mutex_lock(&priv->update_lock);
+ ret = armada_read_sensor(priv, &temperature);
+ mutex_unlock(&priv->update_lock);
+ if (ret)
+ goto enable_irq;
+ } while (temperature >= low_threshold);
+
+ regmap_read(priv->syscon, priv->data->dfx_irq_cause_off, &dummy);
+
+ /* Notify the thermal core that the temperature is acceptable again */
+ thermal_zone_device_update(priv->overheat_sensor,
+ THERMAL_EVENT_UNSPECIFIED);
+
+enable_irq:
+ enable_irq(irq);
+
+ return IRQ_HANDLED;
+}
+
static const struct armada_thermal_data armadaxp_data = {
.init = armadaxp_init,
.temp_shift = 10,
@@ -454,6 +635,9 @@ static const struct armada_thermal_data armada_ap806_data = {
.is_valid_bit = BIT(16),
.temp_shift = 0,
.temp_mask = 0x3ff,
+ .thresh_shift = 3,
+ .hyst_shift = 19,
+ .hyst_mask = 0x3,
.coef_b = -150000LL,
.coef_m = 423ULL,
.coef_div = 1,
@@ -462,6 +646,11 @@ static const struct armada_thermal_data armada_ap806_data = {
.syscon_control0_off = 0x84,
.syscon_control1_off = 0x88,
.syscon_status_off = 0x8C,
+ .dfx_irq_cause_off = 0x108,
+ .dfx_irq_mask_off = 0x10C,
+ .dfx_overheat_irq = BIT(22),
+ .dfx_server_irq_mask_off = 0x104,
+ .dfx_server_irq_en = BIT(1),
.cpu_nr = 4,
};
@@ -470,6 +659,9 @@ static const struct armada_thermal_data armada_cp110_data = {
.is_valid_bit = BIT(10),
.temp_shift = 0,
.temp_mask = 0x3ff,
+ .thresh_shift = 16,
+ .hyst_shift = 26,
+ .hyst_mask = 0x3,
.coef_b = 1172499100ULL,
.coef_m = 2000096ULL,
.coef_div = 4201,
@@ -477,6 +669,11 @@ static const struct armada_thermal_data armada_cp110_data = {
.syscon_control0_off = 0x70,
.syscon_control1_off = 0x74,
.syscon_status_off = 0x78,
+ .dfx_irq_cause_off = 0x108,
+ .dfx_irq_mask_off = 0x10C,
+ .dfx_overheat_irq = BIT(20),
+ .dfx_server_irq_mask_off = 0x104,
+ .dfx_server_irq_en = BIT(1),
};
static const struct of_device_id armada_thermal_id_table[] = {
@@ -586,6 +783,48 @@ static void armada_set_sane_name(struct platform_device *pdev,
} while (insane_char);
}
+/*
+ * The IP can manage to trigger interrupts on overheat situation from all the
+ * sensors. However, the interrupt source changes along with the last selected
+ * source (ie. the last read sensor), which is an inconsistent behavior. Avoid
+ * possible glitches by always selecting back only one channel (arbitrarily: the
+ * first in the DT which has a critical trip point). We also disable sensor
+ * switch during overheat situations.
+ */
+static int armada_configure_overheat_int(struct armada_thermal_priv *priv,
+ struct thermal_zone_device *tz,
+ int sensor_id)
+{
+ /* Retrieve the critical trip point to enable the overheat interrupt */
+ const struct thermal_trip *trips = of_thermal_get_trip_points(tz);
+ int ret;
+ int i;
+
+ if (!trips)
+ return -EINVAL;
+
+ for (i = 0; i < of_thermal_get_ntrips(tz); i++)
+ if (trips[i].type == THERMAL_TRIP_CRITICAL)
+ break;
+
+ if (i == of_thermal_get_ntrips(tz))
+ return -EINVAL;
+
+ ret = armada_select_channel(priv, sensor_id);
+ if (ret)
+ return ret;
+
+ armada_set_overheat_thresholds(priv,
+ trips[i].temperature,
+ trips[i].hysteresis);
+ priv->overheat_sensor = tz;
+ priv->interrupt_source = sensor_id;
+
+ armada_enable_overheat_interrupt(priv);
+
+ return 0;
+}
+
static int armada_thermal_probe(struct platform_device *pdev)
{
struct thermal_zone_device *tz;
@@ -593,7 +832,7 @@ static int armada_thermal_probe(struct platform_device *pdev)
struct armada_drvdata *drvdata;
const struct of_device_id *match;
struct armada_thermal_priv *priv;
- int sensor_id;
+ int sensor_id, irq;
int ret;
match = of_match_device(armada_thermal_id_table, &pdev->dev);
@@ -663,6 +902,23 @@ static int armada_thermal_probe(struct platform_device *pdev)
drvdata->data.priv = priv;
platform_set_drvdata(pdev, drvdata);
+ irq = platform_get_irq(pdev, 0);
+ if (irq == -EPROBE_DEFER)
+ return irq;
+
+ /* The overheat interrupt feature is not mandatory */
+ if (irq > 0) {
+ ret = devm_request_threaded_irq(&pdev->dev, irq,
+ armada_overheat_isr,
+ armada_overheat_isr_thread,
+ 0, NULL, priv);
+ if (ret) {
+ dev_err(&pdev->dev, "Cannot request threaded IRQ %d\n",
+ irq);
+ return ret;
+ }
+ }
+
/*
* There is one channel for the IC and one per CPU (if any), each
* channel has one sensor.
@@ -686,8 +942,20 @@ static int armada_thermal_probe(struct platform_device *pdev)
devm_kfree(&pdev->dev, sensor);
continue;
}
+
+ /*
+ * The first channel that has a critical trip point registered
+ * in the DT will serve as interrupt source. Others possible
+ * critical trip points will simply be ignored by the driver.
+ */
+ if (irq > 0 && !priv->overheat_sensor)
+ armada_configure_overheat_int(priv, tz, sensor->id);
}
+ /* Just complain if no overheat interrupt was set up */
+ if (!priv->overheat_sensor)
+ dev_warn(&pdev->dev, "Overheat interrupt not available\n");
+
return 0;
}