diff options
| -rw-r--r-- | Documentation/hwmon/bt1-pvt.rst | 117 | ||||
| -rw-r--r-- | Documentation/hwmon/index.rst | 1 | ||||
| -rw-r--r-- | drivers/hwmon/Kconfig | 25 | ||||
| -rw-r--r-- | drivers/hwmon/Makefile | 1 | ||||
| -rw-r--r-- | drivers/hwmon/bt1-pvt.c | 1146 | ||||
| -rw-r--r-- | drivers/hwmon/bt1-pvt.h | 244 |
6 files changed, 1534 insertions, 0 deletions
diff --git a/Documentation/hwmon/bt1-pvt.rst b/Documentation/hwmon/bt1-pvt.rst new file mode 100644 index 000000000000..cbb0c0613132 --- /dev/null +++ b/Documentation/hwmon/bt1-pvt.rst @@ -0,0 +1,117 @@ +.. SPDX-License-Identifier: GPL-2.0-only + +Kernel driver bt1-pvt +===================== + +Supported chips: + + * Baikal-T1 PVT sensor (in SoC) + + Prefix: 'bt1-pvt' + + Addresses scanned: - + + Datasheet: Provided by BAIKAL ELECTRONICS upon request and under NDA + +Authors: + Maxim Kaurkin <maxim.kaurkin@baikalelectronics.ru> + Serge Semin <Sergey.Semin@baikalelectronics.ru> + +Description +----------- + +This driver implements support for the hardware monitoring capabilities of the +embedded into Baikal-T1 process, voltage and temperature sensors. PVT IP-core +consists of one temperature and four voltage sensors, which can be used to +monitor the chip internal environment like heating, supply voltage and +transistors performance. The driver can optionally provide the hwmon alarms +for each sensor the PVT controller supports. The alarms functionality is made +compile-time configurable due to the hardware interface implementation +peculiarity, which is connected with an ability to convert data from only one +sensor at a time. Additional limitation is that the controller performs the +thresholds checking synchronously with the data conversion procedure. Due to +these in order to have the hwmon alarms automatically detected the driver code +must switch from one sensor to another, read converted data and manually check +the threshold status bits. Depending on the measurements timeout settings +(update_interval sysfs node value) this design may cause additional burden on +the system performance. So in case if alarms are unnecessary in your system +design it's recommended to have them disabled to prevent the PVT IRQs being +periodically raised to get the data cache/alarms status up to date. By default +in alarm-less configuration the data conversion is performed by the driver +on demand when read operation is requested via corresponding _input-file. + +Temperature Monitoring +---------------------- + +Temperature is measured with 10-bit resolution and reported in millidegree +Celsius. The driver performs all the scaling by itself therefore reports true +temperatures that don't need any user-space adjustments. While the data +translation formulae isn't linear, which gives us non-linear discreteness, +it's close to one, but giving a bit better accuracy for higher temperatures. +The temperature input is mapped as follows (the last column indicates the input +ranges):: + + temp1: CPU embedded diode -48.38C - +147.438C + +In case if the alarms kernel config is enabled in the driver the temperature input +has associated min and max limits which trigger an alarm when crossed. + +Voltage Monitoring +------------------ + +The voltage inputs are also sampled with 10-bit resolution and reported in +millivolts. But in this case the data translation formulae is linear, which +provides a constant measurements discreteness. The data scaling is also +performed by the driver, so returning true millivolts. The voltage inputs are +mapped as follows (the last column indicates the input ranges):: + + in0: VDD (processor core) 0.62V - 1.168V + in1: Low-Vt (low voltage threshold) 0.62V - 1.168V + in2: High-Vt (high voltage threshold) 0.62V - 1.168V + in3: Standard-Vt (standard voltage threshold) 0.62V - 1.168V + +In case if the alarms config is enabled in the driver the voltage inputs +have associated min and max limits which trigger an alarm when crossed. + +Sysfs Attributes +---------------- + +Following is a list of all sysfs attributes that the driver provides, their +permissions and a short description: + +=============================== ======= ======================================= +Name Perm Description +=============================== ======= ======================================= +update_interval RW Measurements update interval per + sensor. +temp1_type RO Sensor type (always 1 as CPU embedded + diode). +temp1_label RO CPU Core Temperature sensor. +temp1_input RO Measured temperature in millidegree + Celsius. +temp1_min RW Low limit for temp input. +temp1_max RW High limit for temp input. +temp1_min_alarm RO Temperature input alarm. Returns 1 if + temperature input went below min limit, + 0 otherwise. +temp1_max_alarm RO Temperature input alarm. Returns 1 if + temperature input went above max limit, + 0 otherwise. +temp1_offset RW Temperature offset in millidegree + Celsius which is added to the + temperature reading by the chip. It can + be used to manually adjust the + temperature measurements within 7.130 + degrees Celsius. +in[0-3]_label RO CPU Voltage sensor (either core or + low/high/standard thresholds). +in[0-3]_input RO Measured voltage in millivolts. +in[0-3]_min RW Low limit for voltage input. +in[0-3]_max RW High limit for voltage input. +in[0-3]_min_alarm RO Voltage input alarm. Returns 1 if + voltage input went below min limit, + 0 otherwise. +in[0-3]_max_alarm RO Voltage input alarm. Returns 1 if + voltage input went above max limit, + 0 otherwise. +=============================== ======= ======================================= diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst index e463fa9a219d..005bf9e124bb 100644 --- a/Documentation/hwmon/index.rst +++ b/Documentation/hwmon/index.rst @@ -44,6 +44,7 @@ Hardware Monitoring Kernel Drivers asc7621 aspeed-pwm-tacho bel-pfe + bt1-pvt coretemp da9052 da9055 diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 3ae303d6c12b..288ae9f63588 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -414,6 +414,31 @@ config SENSORS_ATXP1 This driver can also be built as a module. If so, the module will be called atxp1. +config SENSORS_BT1_PVT + tristate "Baikal-T1 Process, Voltage, Temperature sensor driver" + depends on MIPS_BAIKAL_T1 || COMPILE_TEST + help + If you say yes here you get support for Baikal-T1 PVT sensor + embedded into the SoC. + + This driver can also be built as a module. If so, the module will be + called bt1-pvt. + +config SENSORS_BT1_PVT_ALARMS + bool "Enable Baikal-T1 PVT sensor alarms" + depends on SENSORS_BT1_PVT + help + Baikal-T1 PVT IP-block provides threshold registers for each + supported sensor. But the corresponding interrupts might be + generated by the thresholds comparator only in synchronization with + a data conversion. Additionally there is only one sensor data can + be converted at a time. All of these makes the interface impossible + to be used for the hwmon alarms implementation without periodic + switch between the PVT sensors. By default the data conversion is + performed on demand from the user-space. If this config is enabled + the data conversion will be periodically performed and the data will be + saved in the internal driver cache. + config SENSORS_DRIVETEMP tristate "Hard disk drives with temperature sensors" depends on SCSI && ATA diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index 892174f18f6b..3e32c21f5efe 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -54,6 +54,7 @@ obj-$(CONFIG_SENSORS_ASC7621) += asc7621.o obj-$(CONFIG_SENSORS_ASPEED) += aspeed-pwm-tacho.o obj-$(CONFIG_SENSORS_ATXP1) += atxp1.o obj-$(CONFIG_SENSORS_AXI_FAN_CONTROL) += axi-fan-control.o +obj-$(CONFIG_SENSORS_BT1_PVT) += bt1-pvt.o obj-$(CONFIG_SENSORS_CORETEMP) += coretemp.o obj-$(CONFIG_SENSORS_DA9052_ADC)+= da9052-hwmon.o obj-$(CONFIG_SENSORS_DA9055)+= da9055-hwmon.o diff --git a/drivers/hwmon/bt1-pvt.c b/drivers/hwmon/bt1-pvt.c new file mode 100644 index 000000000000..1a9772fb1f73 --- /dev/null +++ b/drivers/hwmon/bt1-pvt.c @@ -0,0 +1,1146 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2020 BAIKAL ELECTRONICS, JSC + * + * Authors: + * Maxim Kaurkin <maxim.kaurkin@baikalelectronics.ru> + * Serge Semin <Sergey.Semin@baikalelectronics.ru> + * + * Baikal-T1 Process, Voltage, Temperature sensor driver + */ + +#include <linux/bitfield.h> +#include <linux/bitops.h> +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/device.h> +#include <linux/hwmon-sysfs.h> +#include <linux/hwmon.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/ktime.h> +#include <linux/limits.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/seqlock.h> +#include <linux/sysfs.h> +#include <linux/types.h> + +#include "bt1-pvt.h" + +/* + * For the sake of the code simplification we created the sensors info table + * with the sensor names, activation modes, threshold registers base address + * and the thresholds bit fields. + */ +static const struct pvt_sensor_info pvt_info[] = { + PVT_SENSOR_INFO(0, "CPU Core Temperature", hwmon_temp, TEMP, TTHRES), + PVT_SENSOR_INFO(0, "CPU Core Voltage", hwmon_in, VOLT, VTHRES), + PVT_SENSOR_INFO(1, "CPU Core Low-Vt", hwmon_in, LVT, LTHRES), + PVT_SENSOR_INFO(2, "CPU Core High-Vt", hwmon_in, HVT, HTHRES), + PVT_SENSOR_INFO(3, "CPU Core Standard-Vt", hwmon_in, SVT, STHRES), +}; + +/* + * The original translation formulae of the temperature (in degrees of Celsius) + * to PVT data and vice-versa are following: + * N = 1.8322e-8*(T^4) + 2.343e-5*(T^3) + 8.7018e-3*(T^2) + 3.9269*(T^1) + + * 1.7204e2, + * T = -1.6743e-11*(N^4) + 8.1542e-8*(N^3) + -1.8201e-4*(N^2) + + * 3.1020e-1*(N^1) - 4.838e1, + * where T = [-48.380, 147.438]C and N = [0, 1023]. + * They must be accordingly altered to be suitable for the integer arithmetics. + * The technique is called 'factor redistribution', which just makes sure the + * multiplications and divisions are made so to have a result of the operations + * within the integer numbers limit. In addition we need to translate the + * formulae to accept millidegrees of Celsius. Here what they look like after + * the alterations: + * N = (18322e-20*(T^4) + 2343e-13*(T^3) + 87018e-9*(T^2) + 39269e-3*T + + * 17204e2) / 1e4, + * T = -16743e-12*(D^4) + 81542e-9*(D^3) - 182010e-6*(D^2) + 310200e-3*D - + * 48380, + * where T = [-48380, 147438] mC and N = [0, 1023]. + */ +static const struct pvt_poly poly_temp_to_N = { + .total_divider = 10000, + .terms = { + {4, 18322, 10000, 10000}, + {3, 2343, 10000, 10}, + {2, 87018, 10000, 10}, + {1, 39269, 1000, 1}, + {0, 1720400, 1, 1} + } +}; + +static const struct pvt_poly poly_N_to_temp = { + .total_divider = 1, + .terms = { + {4, -16743, 1000, 1}, + {3, 81542, 1000, 1}, + {2, -182010, 1000, 1}, + {1, 310200, 1000, 1}, + {0, -48380, 1, 1} + } +}; + +/* + * Similar alterations are performed for the voltage conversion equations. + * The original formulae are: + * N = 1.8658e3*V - 1.1572e3, + * V = (N + 1.1572e3) / 1.8658e3, + * where V = [0.620, 1.168] V and N = [0, 1023]. + * After the optimization they looks as follows: + * N = (18658e-3*V - 11572) / 10, + * V = N * 10^5 / 18658 + 11572 * 10^4 / 18658. + */ +static const struct pvt_poly poly_volt_to_N = { + .total_divider = 10, + .terms = { + {1, 18658, 1000, 1}, + {0, -11572, 1, 1} + } +}; + +static const struct pvt_poly poly_N_to_volt = { + .total_divider = 10, + .terms = { + {1, 100000, 18658, 1}, + {0, 115720000, 1, 18658} + } +}; + +/* + * Here is the polynomial calculation function, which performs the + * redistributed terms calculations. It's pretty straightforward. We walk + * over each degree term up to the free one, and perform the redistributed + * multiplication of the term coefficient, its divider (as for the rationale + * fraction representation), data power and the rational fraction divider + * leftover. Then all of this is collected in a total sum variable, which + * value is normalized by the total divider before being returned. + */ +static long pvt_calc_poly(const struct pvt_poly *poly, long data) +{ + const struct pvt_poly_term *term = poly->terms; + long tmp, ret = 0; + int deg; + + do { + tmp = term->coef; + for (deg = 0; deg < term->deg; ++deg) + tmp = mult_frac(tmp, data, term->divider); + ret += tmp / term->divider_leftover; + } while ((term++)->deg); + + return ret / poly->total_divider; +} + +static inline u32 pvt_update(void __iomem *reg, u32 mask, u32 data) +{ + u32 old; + + old = readl_relaxed(reg); + writel((old & ~mask) | (data & mask), reg); + + return old & mask; +} + +/* + * Baikal-T1 PVT mode can be updated only when the controller is disabled. + * So first we disable it, then set the new mode together with the controller + * getting back enabled. The same concerns the temperature trim and + * measurements timeout. If it is necessary the interface mutex is supposed + * to be locked at the time the operations are performed. + */ +static inline void pvt_set_mode(struct pvt_hwmon *pvt, u32 mode) +{ + u32 old; + + mode = FIELD_PREP(PVT_CTRL_MODE_MASK, mode); + + old = pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_EN, 0); + pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_MODE_MASK | PVT_CTRL_EN, + mode | old); +} + +static inline u32 pvt_calc_trim(long temp) +{ + temp = clamp_val(temp, 0, PVT_TRIM_TEMP); + + return DIV_ROUND_UP(temp, PVT_TRIM_STEP); +} + +static inline void pvt_set_trim(struct pvt_hwmon *pvt, u32 trim) +{ + u32 old; + + trim = FIELD_PREP(PVT_CTRL_TRIM_MASK, trim); + + old = pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_EN, 0); + pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_TRIM_MASK | PVT_CTRL_EN, + trim | old); +} + +static inline void pvt_set_tout(struct pvt_hwmon *pvt, u32 tout) +{ + u32 old; + + old = pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_EN, 0); + writel(tout, pvt->regs + PVT_TTIMEOUT); + pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_EN, old); +} + +/* + * This driver can optionally provide the hwmon alarms for each sensor the PVT + * controller supports. The alarms functionality is made compile-time + * configurable due to the hardware interface implementation peculiarity + * described further in this comment. So in case if alarms are unnecessary in + * your system design it's recommended to have them disabled to prevent the PVT + * IRQs being periodically raised to get the data cache/alarms status up to + * date. + * + * Baikal-T1 PVT embedded controller is based on the Analog Bits PVT sensor, + * but is equipped with a dedicated control wrapper. It exposes the PVT + * sub-block registers space via the APB3 bus. In addition the wrapper provides + * a common interrupt vector of the sensors conversion completion events and + * threshold value alarms. Alas the wrapper interface hasn't been fully thought + * through. There is only one sensor can be activated at a time, for which the + * thresholds comparator is enabled right after the data conversion is + * completed. Due to this if alarms need to be implemented for all available + * sensors we can't just set the thresholds and enable the interrupts. We need + * to enable the sensors one after another and let the controller to detect + * the alarms by itself at each conversion. This also makes pointless to handle + * the alarms interrupts, since in occasion they happen synchronously with + * data conversion completion. The best driver design would be to have the + * completion interrupts enabled only and keep the converted value in the + * driver data cache. This solution is implemented if hwmon alarms are enabled + * in this driver. In case if the alarms are disabled, the conversion is + * performed on demand at the time a sensors input file is read. + */ + +#if defined(CONFIG_SENSORS_BT1_PVT_ALARMS) + +#define pvt_hard_isr NULL + +static irqreturn_t pvt_soft_isr(int irq, void *data) +{ + const struct pvt_sensor_info *info; + struct pvt_hwmon *pvt = data; + struct pvt_cache *cache; + u32 val, thres_sts, old; + + /* + * DVALID bit will be cleared by reading the data. We need to save the + * status before the next conversion happens. Threshold events will be + * handled a bit later. + */ + thres_sts = readl(pvt->regs + PVT_RAW_INTR_STAT); + + /* + * Then lets recharge the PVT interface with the next sampling mode. + * Lock the interface mutex to serialize trim, timeouts and alarm + * thresholds settings. + */ + cache = &pvt->cache[pvt->sensor]; + info = &pvt_info[pvt->sensor]; + pvt->sensor = (pvt->sensor == PVT_SENSOR_LAST) ? + PVT_SENSOR_FIRST : (pvt->sensor + 1); + + /* + * For some reason we have to mask the interrupt before changing the + * mode, otherwise sometimes the temperature mode doesn't get + * activated even though the actual mode in the ctrl register + * corresponds to one. Then we read the data. By doing so we also + * recharge the data conversion. After this the mode corresponding + * to the next sensor in the row is set. Finally we enable the + * interrupts back. + */ + mutex_lock(&pvt->iface_mtx); + + old = pvt_update(pvt->regs + PVT_INTR_MASK, PVT_INTR_DVALID, + PVT_INTR_DVALID); + + val = readl(pvt->regs + PVT_DATA); + + pvt_set_mode(pvt, pvt_info[pvt->sensor].mode); + + pvt_update(pvt->regs + PVT_INTR_MASK, PVT_INTR_DVALID, old); + + mutex_unlock(&pvt->iface_mtx); + + /* + * We can now update the data cache with data just retrieved from the + * sensor. Lock write-seqlock to make sure the reader has a coherent + * data. + */ + write_seqlock(&cache->data_seqlock); + + cache->data = FIELD_GET(PVT_DATA_DATA_MASK, val); + + write_sequnlock(&cache->data_seqlock); + + /* + * While PVT core is doing the next mode data conversion, we'll check + * whether the alarms were triggered for the current sensor. Note that + * according to the documentation only one threshold IRQ status can be + * set at a time, that's why if-else statement is utilized. + */ + if ((thres_sts & info->thres_sts_lo) ^ cache->thres_sts_lo) { + WRITE_ONCE(cache->thres_sts_lo, thres_sts & info->thres_sts_lo); + hwmon_notify_event(pvt->hwmon, info->type, info->attr_min_alarm, + info->channel); + } else if ((thres_sts & info->thres_sts_hi) ^ cache->thres_sts_hi) { + WRITE_ONCE(cache->thres_sts_hi, thres_sts & info->thres_sts_hi); + hwmon_notify_event(pvt->hwmon, info->type, info->attr_max_alarm, + info->channel); + } + + return IRQ_HANDLED; +} + +inline umode_t pvt_limit_is_visible(enum pvt_sensor_type type) +{ + return 0644; +} + +inline umode_t pvt_alarm_is_visible(enum pvt_sensor_type type) +{ + return 0444; +} + +static int pvt_read_data(struct pvt_hwmon *pvt, enum pvt_sensor_type type, + long *val) +{ + struct pvt_cache *cache = &pvt->cache[type]; + unsigned int seq; + u32 data; + + do { + seq = read_seqbegin(&cache->data_seqlock); + data = cache->data; + } while (read_seqretry(&cache->data_seqlock, seq)); + + if (type == PVT_TEMP) + *val = pvt_calc_poly(&poly_N_to_temp, data); + else + *val = pvt_calc_poly(&poly_N_to_volt, data); + + return 0; +} + +static int pvt_read_limit(struct pvt_hwmon *pvt, enum pvt_sensor_type type, + bool is_low, long *val) +{ + u32 data; + + /* No need in serialization, since it is just read from MMIO. */ + data = readl(pvt->regs + pvt_info[type].thres_base); + + if (is_low) + data = FIELD_GET(PVT_THRES_LO_MASK, data); + else + data = FIELD_GET(PVT_THRES_HI_MASK, data); + + if (type == PVT_TEMP) + *val = pvt_calc_poly(&poly_N_to_temp, data); + else + *val = pvt_calc_poly(&poly_N_to_volt, data); + + return 0; +} + +static int pvt_write_limit(struct pvt_hwmon *pvt, enum pvt_sensor_type type, + bool is_low, long val) +{ + u32 data, limit, mask; + int ret; + + if (type == PVT_TEMP) { + val = clamp(val, PVT_TEMP_MIN, PVT_TEMP_MAX); + data = pvt_calc_poly(&poly_temp_to_N, val); + } else { + val = clamp(val, PVT_VOLT_MIN, PVT_VOLT_MAX); + data = pvt_calc_poly(&poly_volt_to_N, val); + } + + /* Serialize limit update, since a part of the register is changed. */ + ret = mutex_lock_interruptible(&pvt->iface_mtx); + if (ret) + return ret; + + /* Make sure the upper and lower ranges don't intersect. */ + limit = readl(pvt->regs + pvt_info[type].thres_base); + if (is_low) { + limit = FIELD_GET(PVT_THRES_HI_MASK, limit); + data = clamp_val(data, PVT_DATA_MIN, limit); + data = FIELD_PREP(PVT_THRES_LO_MASK, data); + mask = PVT_THRES_LO_MASK; + } else { + limit = FIELD_GET(PVT_THRES_LO_MASK, limit); + data = clamp_val(data, limit, PVT_DATA_MAX); + data = FIELD_PREP(PVT_THRES_HI_MASK, data); + mask = PVT_THRES_HI_MASK; + } + + pvt_update(pvt->regs + pvt_info[type].thres_base, mask, data); + + mutex_unlock(&pvt->iface_mtx); + + return 0; +} + +static int pvt_read_alarm(struct pvt_hwmon *pvt, enum pvt_sensor_type type, + bool is_low, long *val) +{ + if (is_low) + *val = !!READ_ONCE(pvt->cache[type].thres_sts_lo); + else + *val = !!READ_ONCE(pvt->cache[type].thres_sts_hi); + + return 0; +} + +static const struct hwmon_channel_info *pvt_channel_info[] = { + HWMON_CHANNEL_INFO(chip, + HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL), + HWMON_CHANNEL_INFO(temp, + HWMON_T_INPUT | HWMON_T_TYPE | HWMON_T_LABEL | + HWMON_T_MIN | HWMON_T_MIN_ALARM | + HWMON_T_MAX | HWMON_T_MAX_ALARM | + HWMON_T_OFFSET), + HWMON_CHANNEL_INFO(in, + HWMON_I_INPUT | HWMON_I_LABEL | + HWMON_I_MIN | HWMON_I_MIN_ALARM | + HWMON_I_MAX | HWMON_I_MAX_ALARM, + HWMON_I_INPUT | HWMON_I_LABEL | + HWMON_I_MIN | HWMON_I_MIN_ALARM | + HWMON_I_MAX | HWMON_I_MAX_ALARM, + HWMON_I_INPUT | HWMON_I_LABEL | + HWMON_I_MIN | HWMON_I_MIN_ALARM | + HWMON_I_MAX | HWMON_I_MAX_ALARM, + HWMON_I_INPUT | HWMON_I_LABEL | + HWMON_I_MIN | HWMON_I_MIN_ALARM | + HWMON_I_MAX | HWMON_I_MAX_ALARM), + NULL +}; + +#else /* !CONFIG_SENSORS_BT1_PVT_ALARMS */ + +static irqreturn_t pvt_hard_isr(int irq, void *data) +{ + struct pvt_hwmon *pvt = data; + struct pvt_cache *cache; + u32 val; + + /* + * Mask the DVALID interrupt so after exiting from the handler a + * repeated conversion wouldn't happen. + */ + pvt_update(pvt->regs + PVT_INTR_MASK, PVT_INTR_DVALID, + PVT_INTR_DVALID); + + /* + * Nothing special for alarm-less driver. Just read the data, update + * the cache and notify a waiter of this event. + */ + val = readl(pvt->regs + PVT_DATA); + if (!(val & PVT_DATA_VALID)) { + dev_err(pvt->dev, "Got IRQ when data isn't valid\n"); + return IRQ_HANDLED; + } + + cache = &pvt->cache[pvt->sensor]; + + WRITE_ONCE(cache->data, FIELD_GET(PVT_DATA_DATA_MASK, val)); + + complete(&cache->conversion); + + return IRQ_HANDLED; +} + +#define pvt_soft_isr NULL + +inline umode_t pvt_limit_is_visible(enum pvt_sensor_type type) +{ + return 0; +} + +inline umode_t pvt_alarm_is_visible(enum pvt_sensor_type type) +{ + return 0; +} + +static int pvt_read_data(struct pvt_hwmon *pvt, enum pvt_sensor_type type, + long *val) +{ + struct pvt_cache *cache = &pvt->cache[type]; + u32 data; + int ret; + + /* + * Lock PVT conversion interface until data cache is updated. The + * data read procedure is following: set the requested PVT sensor + * mode, enable IRQ and conversion, wait until conversion is finished, + * then disable conversion and IRQ, and read the cached data. + */ + ret = mutex_lock_interruptible(&pvt->iface_mtx); + if (ret) + return ret; + + pvt->sensor = type; + pvt_set_mode(pvt, pvt_info[type].mode); + + /* + * Unmask the DVALID interrupt and enable the sensors conversions. + * Do the reverse procedure when conversion is done. + */ + pvt_update(pvt->regs + PVT_INTR_MASK, PVT_INTR_DVALID, 0); + pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_EN, PVT_CTRL_EN); + + wait_for_completion(&cache->conversion); + + pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_EN, 0); + pvt_update(pvt->regs + PVT_INTR_MASK, PVT_INTR_DVALID, + PVT_INTR_DVALID); + + data = READ_ONCE(cache->data); + + mutex_unlock(&pvt->iface_mtx); + + if (type == PVT_TEMP) + *val = pvt_calc_poly(&poly_N_to_temp, data); + else + *val = pvt_calc_poly(&poly_N_to_volt, data); + + return 0; +} + +static int pvt_read_limit(struct pvt_hwmon *pvt, enum pvt_sensor_type type, + bool is_low, long *val) +{ + return -EOPNOTSUPP; +} + +static int pvt_write_limit(struct pvt_hwmon *pvt, enum pvt_sensor_type type, + bool is_low, long val) +{ + return -EOPNOTSUPP; +} + +static int pvt_read_alarm(struct pvt_hwmon *pvt, enum pvt_sensor_type type, + bool is_low, long *val) +{ + return -EOPNOTSUPP; +} + +static const struct hwmon_channel_info *pvt_channel_info[] = { + HWMON_CHANNEL_INFO(chip, + HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL), + HWMON_CHANNEL_INFO(temp, + HWMON_T_INPUT | HWMON_T_TYPE | HWMON_T_LABEL | + HWMON_T_OFFSET), + HWMON_CHANNEL_INFO(in, + HWMON_I_INPUT | HWMON_I_LABEL, + HWMON_I_INPUT | HWMON_I_LABEL, + HWMON_I_INPUT | HWMON_I_LABEL, + HWMON_I_INPUT | HWMON_I_LABEL), + NULL +}; + +#endif /* !CONFIG_SENSORS_BT1_PVT_ALARMS */ + +static inline bool pvt_hwmon_channel_is_valid(enum hwmon_sensor_types type, + int ch) +{ + switch (type) { + case hwmon_temp: + if (ch < 0 || ch >= PVT_TEMP_CHS) + return false; + break; + case hwmon_in: + if (ch < 0 || ch >= PVT_VOLT_CHS) + return false; + break; + default: + break; + } + + /* The rest of the types are independent from the channel number. */ + return true; +} + +static umode_t pvt_hwmon_is_visible(const void *data, + enum hwmon_sensor_types type, + u32 attr, int ch) +{ + if (!pvt_hwmon_channel_is_valid(type, ch)) + return 0; + + switch (type) { + case hwmon_chip: + switch (attr) { + case hwmon_chip_update_interval: + return 0644; + } + break; + case hwmon_temp: + switch (attr) { + case hwmon_temp_input: + case hwmon_temp_type: + case hwmon_temp_label: + return 0444; + case hwmon_temp_min: + case hwmon_temp_max: + return pvt_limit_is_visible(ch); + case hwmon_temp_min_alarm: + case hwmon_temp_max_alarm: + return pvt_alarm_is_visible(ch); + case hwmon_temp_offset: + return 0644; + } + break; + case hwmon_in: + switch (attr) { + case hwmon_in_input: + case hwmon_in_label: + return 0444; + case hwmon_in_min: + case hwmon_in_max: + return pvt_limit_is_visible(PVT_VOLT + ch); + case hwmon_in_min_alarm: + case hwmon_in_max_alarm: + return pvt_alarm_is_visible(PVT_VOLT + ch); + } + break; + default: + break; + } + + return 0; +} + +static int pvt_read_trim(struct pvt_hwmon *pvt, long *val) +{ + u32 data; + + data = readl(pvt->regs + PVT_CTRL); + *val = FIELD_GET(PVT_CTRL_TRIM_MASK, data) * PVT_TRIM_STEP; + + return 0; +} + +static int pvt_write_trim(struct pvt_hwmon *pvt, long val) +{ + u32 trim; + int ret; + + /* + * Serialize trim update, since a part of the register is changed and + * the controller is supposed to be disabled during this operation. + */ + ret = mutex_lock_interruptible(&pvt->iface_mtx); + if (ret) + return ret; + + trim = pvt_calc_trim(val); + pvt_set_trim(pvt, trim); + + mutex_unlock(&pvt->iface_mtx); + + return 0; +} + +static int pvt_read_timeout(struct pvt_hwmon *pvt, long *val) +{ + unsigned long rate; + ktime_t kt; + u32 data; + + rate = clk_get_rate(pvt->clks[PVT_CLOCK_REF].clk); + if (!rate) + return -ENODEV; + + /* + * Don't bother with mutex here, since we just read data from MMIO. + * We also have to scale the ticks timeout up to compensate the + * ms-ns-data translations. + */ + data = readl(pvt->regs + PVT_TTIMEOUT) + 1; + + /* + * Calculate ref-clock based delay (Ttotal) between two consecutive + * data samples of the same sensor. So we first must calculate the + * delay introduced by the internal ref-clock timer (Tref * Fclk). + * Then add the constant timeout cuased by each conversion latency + * (Tmin). The basic formulae for each conversion is following: + * Ttotal = Tref * Fclk + Tmin + * Note if alarms are enabled the sensors are polled one after + * another, so in order to have the delay being applicable for each + * sensor the requested value must be equally redistirbuted. + */ +#if defined(CONFIG_SENSORS_BT1_PVT_ALARMS) + kt = ktime_set(PVT_SENSORS_NUM * (u64)data, 0); + kt = ktime_divns(kt, rate); + kt = ktime_add_ns(kt, PVT_SENSORS_NUM * PVT_TOUT_MIN); +#else + kt = ktime_set(data, 0); + kt = ktime_divns(kt, rate); + kt = ktime_add_ns(kt, PVT_TOUT_MIN); +#endif + + /* Return the result in msec as hwmon sysfs interface requires. */ + *val = ktime_to_ms(kt); + + return 0; +} + +static int pvt_write_timeout(struct pvt_hwmon *pvt, long val) +{ + unsigned long rate; + ktime_t kt; + u32 data; + int ret; + + rate = clk_get_rate(pvt->clks[PVT_CLOCK_REF].clk); + if (!rate) + return -ENODEV; + + /* + * If alarms are enabled, the requested timeout must be divided + * between all available sensors to have the requested delay + * applicable to each individual sensor. + */ + kt = ms_to_ktime(val); +#if defined(CONFIG_SENSORS_BT1_PVT_ALARMS) + kt = ktime_divns(kt, PVT_SENSORS_NUM); +#endif + + /* + * Subtract a constant lag, which always persists due to the limited + * PVT sampling rate. Make sure the timeout is not negative. + */ + kt = ktime_sub_ns(kt, PVT_TOUT_MIN); + if (ktime_to_ns(kt) < 0) + kt = ktime_set(0, 0); + + /* + * Finally recalculate the timeout in terms of the reference clock + * period. + */ + data = ktime_divns(kt * rate, NSEC_PER_SEC); + + /* + * Update the measurements delay, but lock the interface first, since + * we have to disable PVT in order to have the new delay actually + * updated. + */ + ret = mutex_lock_interruptible(&pvt->iface_mtx); + if (ret) + return ret; + + pvt_set_tout(pvt, data); + + mutex_unlock(&pvt->iface_mtx); + + return 0; +} + +static int pvt_hwmon_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int ch, long *val) +{ + struct pvt_hwmon *pvt = dev_get_drvdata(dev); + + if (!pvt_hwmon_channel_is_valid(type, ch)) + return -EINVAL; + + switch (type) { + case hwmon_chip: + switch (attr) { + case hwmon_chip_update_interval: + return pvt_read_timeout(pvt, val); + } + break; + case hwmon_temp: + switch (attr) { + case hwmon_temp_input: + return pvt_read_data(pvt, ch, val); + case hwmon_temp_type: + *val = 1; + return 0; + case hwmon_temp_min: + return pvt_read_limit(pvt, ch, true, val); + case hwmon_temp_max: + return pvt_read_limit(pvt, ch, false, val); + case hwmon_temp_min_alarm: + return pvt_read_alarm(pvt, ch, true, val); + case hwmon_temp_max_alarm: + return pvt_read_alarm(pvt, ch, false, val); + case hwmon_temp_offset: + return pvt_read_trim(pvt, val); + } + break; + case hwmon_in: + switch (attr) { + case hwmon_in_input: + return pvt_read_data(pvt, PVT_VOLT + ch, val); + case hwmon_in_min: + return pvt_read_limit(pvt, PVT_VOLT + ch, true, val); + case hwmon_in_max: + return pvt_read_limit(pvt, PVT_VOLT + ch, false, val); + case hwmon_in_min_alarm: + return pvt_read_alarm(pvt, PVT_VOLT + ch, true, val); + case hwmon_in_max_alarm: + return pvt_read_alarm(pvt, PVT_VOLT + ch, false, val); + } + break; + default: + break; + } + + return -EOPNOTSUPP; +} + +static int pvt_hwmon_read_string(struct device *dev, + enum hwmon_sensor_types type, + u32 attr, int ch, const char **str) +{ + if (!pvt_hwmon_channel_is_valid(type, ch)) + return -EINVAL; + + switch (type) { + case hwmon_temp: + switch (attr) { + case hwmon_temp_label: + *str = pvt_info[ch].label; + return 0; + } + break; + case hwmon_in: + switch (attr) { + case hwmon_in_label: + *str = pvt_info[PVT_VOLT + ch].label; + return 0; + } + break; + default: + break; + } + + return -EOPNOTSUPP; +} + +static int pvt_hwmon_write(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int ch, long val) +{ + struct pvt_hwmon *pvt = dev_get_drvdata(dev); + + if (!pvt_hwmon_channel_is_valid(type, ch)) + return -EINVAL; + + switch (type) { + case hwmon_chip: + switch (attr) { + case hwmon_chip_update_interval: + return pvt_write_timeout(pvt, val); + } + break; + case hwmon_temp: + switch (attr) { + case hwmon_temp_min: + return pvt_write_limit(pvt, ch, true, val); + case hwmon_temp_max: + return pvt_write_limit(pvt, ch, false, val); + case hwmon_temp_offset: + return pvt_write_trim(pvt, val); + } + break; + case hwmon_in: + switch (attr) { + case hwmon_in_min: + return pvt_write_limit(pvt, PVT_VOLT + ch, true, val); + case hwmon_in_max: + return pvt_write_limit(pvt, PVT_VOLT + ch, false, val); + } + break; + default: + break; + } + + return -EOPNOTSUPP; +} + +static const struct hwmon_ops pvt_hwmon_ops = { + .is_visible = pvt_hwmon_is_visible, + .read = pvt_hwmon_read, + .read_string = pvt_hwmon_read_string, + .write = pvt_hwmon_write +}; + +static const struct hwmon_chip_info pvt_hwmon_info = { + .ops = &pvt_hwmon_ops, + .info = pvt_channel_info +}; + +static void pvt_clear_data(void *data) +{ + struct pvt_hwmon *pvt = data; +#if !defined(CONFIG_SENSORS_BT1_PVT_ALARMS) + int idx; + + for (idx = 0; idx < PVT_SENSORS_NUM; ++idx) + complete_all(&pvt->cache[idx].conversion); +#endif + + mutex_destroy(&pvt->iface_mtx); +} + +static struct pvt_hwmon *pvt_create_data(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct pvt_hwmon *pvt; + int ret, idx; + + pvt = devm_kzalloc(dev, sizeof(*pvt), GFP_KERNEL); + if (!pvt) + return ERR_PTR(-ENOMEM); + + ret = devm_add_action(dev, pvt_clear_data, pvt); + if (ret) { + dev_err(dev, "Can't add PVT data clear action\n"); + return ERR_PTR(ret); + } + + pvt->dev = dev; + pvt->sensor = PVT_SENSOR_FIRST; + mutex_init(&pvt->iface_mtx); + +#if defined(CONFIG_SENSORS_BT1_PVT_ALARMS) + for (idx = 0; idx < PVT_SENSORS_NUM; ++idx) + seqlock_init(&pvt->cache[idx].data_seqlock); +#else + for (idx = 0; idx < PVT_SENSORS_NUM; ++idx) + init_completion(&pvt->cache[idx].conversion); +#endif + + return pvt; +} + +static int pvt_request_regs(struct pvt_hwmon *pvt) +{ + struct platform_device *pdev = to_platform_device(pvt->dev); + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(pvt->dev, "Couldn't find PVT memresource\n"); + return -EINVAL; + } + + pvt->regs = devm_ioremap_resource(pvt->dev, res); + if (IS_ERR(pvt->regs)) { + dev_err(pvt->dev, "Couldn't map PVT registers\n"); + return PTR_ERR(pvt->regs); + } + + return 0; +} + +static void pvt_disable_clks(void *data) +{ + struct pvt_hwmon *pvt = data; + + clk_bulk_disable_unprepare(PVT_CLOCK_NUM, pvt->clks); +} + +static int pvt_request_clks(struct pvt_hwmon *pvt) +{ + int ret; + + pvt->clks[PVT_CLOCK_APB].id = "pclk"; + pvt->clks[PVT_CLOCK_REF].id = "ref"; + + ret = devm_clk_bulk_get(pvt->dev, PVT_CLOCK_NUM, pvt->clks); + if (ret) { + dev_err(pvt->dev, "Couldn't get PVT clocks descriptors\n"); + return ret; + } + + ret = clk_bulk_prepare_enable(PVT_CLOCK_NUM, pvt->clks); + if (ret) { + dev_err(pvt->dev, "Couldn't enable the PVT clocks\n"); + return ret; + } + + ret = devm_add_action_or_reset(pvt->dev, pvt_disable_clks, pvt); + if (ret) { + dev_err(pvt->dev, "Can't add PVT clocks disable action\n"); + return ret; + } + + return 0; +} + +static void pvt_init_iface(struct pvt_hwmon *pvt) +{ + u32 trim, temp; + + /* + * Make sure all interrupts and controller are disabled so not to + * accidentally have ISR executed before the driver data is fully + * initialized. Clear the IRQ status as well. + */ + pvt_update(pvt->regs + PVT_INTR_MASK, PVT_INTR_ALL, PVT_INTR_ALL); + pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_EN, 0); + readl(pvt->regs + PVT_CLR_INTR); + readl(pvt->regs + PVT_DATA); + + /* Setup default sensor mode, timeout and temperature trim. */ + pvt_set_mode(pvt, pvt_info[pvt->sensor].mode); + pvt_set_tout(pvt, PVT_TOUT_DEF); + + trim = PVT_TRIM_DEF; + if (!of_property_read_u32(pvt->dev->of_node, + "baikal,pvt-temp-offset-millicelsius", &temp)) + trim = pvt_calc_trim(temp); + + pvt_set_trim(pvt, trim); +} + +static int pvt_request_irq(struct pvt_hwmon *pvt) +{ + struct platform_device *pdev = to_platform_device(pvt->dev); + int ret; + + pvt->irq = platform_get_irq(pdev, 0); + if (pvt->irq < 0) + return pvt->irq; + + ret = devm_request_threaded_irq(pvt->dev, pvt->irq, + pvt_hard_isr, pvt_soft_isr, +#if defined(CONFIG_SENSORS_BT1_PVT_ALARMS) + IRQF_SHARED | IRQF_TRIGGER_HIGH | + IRQF_ONESHOT, +#else + IRQF_SHARED | IRQF_TRIGGER_HIGH, +#endif + "pvt", pvt); + if (ret) { + dev_err(pvt->dev, "Couldn't request PVT IRQ\n"); + return ret; + } + + return 0; +} + +static int pvt_create_hwmon(struct pvt_hwmon *pvt) +{ + pvt->hwmon = devm_hwmon_device_register_with_info(pvt->dev, "pvt", pvt, + &pvt_hwmon_info, NULL); + if (IS_ERR(pvt->hwmon)) { + dev_err(pvt->dev, "Couldn't create hwmon device\n"); + return PTR_ERR(pvt->hwmon); + } + + return 0; +} + +#if defined(CONFIG_SENSORS_BT1_PVT_ALARMS) + +static void pvt_disable_iface(void *data) +{ + struct pvt_hwmon *pvt = data; + + mutex_lock(&pvt->iface_mtx); + pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_EN, 0); + pvt_update(pvt->regs + PVT_INTR_MASK, PVT_INTR_DVALID, + PVT_INTR_DVALID); + mutex_unlock(&pvt->iface_mtx); +} + +static int pvt_enable_iface(struct pvt_hwmon *pvt) +{ + int ret; + + ret = devm_add_action(pvt->dev, pvt_disable_iface, pvt); + if (ret) { + dev_err(pvt->dev, "Can't add PVT disable interface action\n"); + return ret; + } + + /* + * Enable sensors data conversion and IRQ. We need to lock the + * interface mutex since hwmon has just been created and the + * corresponding sysfs files are accessible from user-space, + * which theoretically may cause races. + */ + mutex_lock(&pvt->iface_mtx); + pvt_update(pvt->regs + PVT_INTR_MASK, PVT_INTR_DVALID, 0); + pvt_update(pvt->regs + PVT_CTRL, PVT_CTRL_EN, PVT_CTRL_EN); + mutex_unlock(&pvt->iface_mtx); + + return 0; +} + +#else /* !CONFIG_SENSORS_BT1_PVT_ALARMS */ + +static int pvt_enable_iface(struct pvt_hwmon *pvt) +{ + return 0; +} + +#endif /* !CONFIG_SENSORS_BT1_PVT_ALARMS */ + +static int pvt_probe(struct platform_device *pdev) +{ + struct pvt_hwmon *pvt; + int ret; + + pvt = pvt_create_data(pdev); + if (IS_ERR(pvt)) + return PTR_ERR(pvt); + + ret = pvt_request_regs(pvt); + if (ret) + return ret; + + ret = pvt_request_clks(pvt); + if (ret) + return ret; + + pvt_init_iface(pvt); + + ret = pvt_request_irq(pvt); + if (ret) + return ret; + + ret = pvt_create_hwmon(pvt); + if (ret) + return ret; + + ret = pvt_enable_iface(pvt); + if (ret) + return ret; + + return 0; +} + +static const struct of_device_id pvt_of_match[] = { + { .compatible = "baikal,bt1-pvt" }, + { } +}; +MODULE_DEVICE_TABLE(of, pvt_of_match); + +static struct platform_driver pvt_driver = { + .probe = pvt_probe, + .driver = { + .name = "bt1-pvt", + .of_match_table = pvt_of_match + } +}; +module_platform_driver(pvt_driver); + +MODULE_AUTHOR("Maxim Kaurkin <maxim.kaurkin@baikalelectronics.ru>"); +MODULE_DESCRIPTION("Baikal-T1 PVT driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/hwmon/bt1-pvt.h b/drivers/hwmon/bt1-pvt.h new file mode 100644 index 000000000000..5eac73e94885 --- /dev/null +++ b/drivers/hwmon/bt1-pvt.h @@ -0,0 +1,244 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2020 BAIKAL ELECTRONICS, JSC + * + * Baikal-T1 Process, Voltage, Temperature sensor driver + */ +#ifndef __HWMON_BT1_PVT_H__ +#define __HWMON_BT1_PVT_H__ + +#include <linux/completion.h> +#include <linux/hwmon.h> +#include <linux/kernel.h> +#include <linux/mutex.h> +#include <linux/seqlock.h> + +/* Baikal-T1 PVT registers and their bitfields */ +#define PVT_CTRL 0x00 +#define PVT_CTRL_EN BIT(0) +#define PVT_CTRL_MODE_FLD 1 +#define PVT_CTRL_MODE_MASK GENMASK(3, PVT_CTRL_MODE_FLD) +#define PVT_CTRL_MODE_TEMP 0x0 +#define PVT_CTRL_MODE_VOLT 0x1 +#define PVT_CTRL_MODE_LVT 0x2 +#define PVT_CTRL_MODE_HVT 0x4 +#define PVT_CTRL_MODE_SVT 0x6 +#define PVT_CTRL_TRIM_FLD 4 +#define PVT_CTRL_TRIM_MASK GENMASK(8, PVT_CTRL_TRIM_FLD) +#define PVT_DATA 0x04 +#define PVT_DATA_VALID BIT(10) +#define PVT_DATA_DATA_FLD 0 +#define PVT_DATA_DATA_MASK GENMASK(9, PVT_DATA_DATA_FLD) +#define PVT_TTHRES 0x08 +#define PVT_VTHRES 0x0C +#define PVT_LTHRES 0x10 +#define PVT_HTHRES 0x14 +#define PVT_STHRES 0x18 +#define PVT_THRES_LO_FLD 0 +#define PVT_THRES_LO_MASK GENMASK(9, PVT_THRES_LO_FLD) +#define PVT_THRES_HI_FLD 10 +#define PVT_THRES_HI_MASK GENMASK(19, PVT_THRES_HI_FLD) +#define PVT_TTIMEOUT 0x1C +#define PVT_INTR_STAT 0x20 +#define PVT_INTR_MASK 0x24 +#define PVT_RAW_INTR_STAT 0x28 +#define PVT_INTR_DVALID BIT(0) +#define PVT_INTR_TTHRES_LO BIT(1) +#define PVT_INTR_TTHRES_HI BIT(2) +#define PVT_INTR_VTHRES_LO BIT(3) +#define PVT_INTR_VTHRES_HI BIT(4) +#define PVT_INTR_LTHRES_LO BIT(5) +#define PVT_INTR_LTHRES_HI BIT(6) +#define PVT_INTR_HTHRES_LO BIT(7) +#define PVT_INTR_HTHRES_HI BIT(8) +#define PVT_INTR_STHRES_LO BIT(9) +#define PVT_INTR_STHRES_HI BIT(10) +#define PVT_INTR_ALL GENMASK(10, 0) +#define PVT_CLR_INTR 0x2C + +/* + * PVT sensors-related limits and default values + * @PVT_TEMP_MIN: Minimal temperature in millidegrees of Celsius. + * @PVT_TEMP_MAX: Maximal temperature in millidegrees of Celsius. + * @PVT_TEMP_CHS: Number of temperature hwmon channels. + * @PVT_VOLT_MIN: Minimal voltage in mV. + * @PVT_VOLT_MAX: Maximal voltage in mV. + * @PVT_VOLT_CHS: Number of voltage hwmon channels. + * @PVT_DATA_MIN: Minimal PVT raw data value. + * @PVT_DATA_MAX: Maximal PVT raw data value. + * @PVT_TRIM_MIN: Minimal temperature sensor trim value. + * @PVT_TRIM_MAX: Maximal temperature sensor trim value. + * @PVT_TRIM_DEF: Default temperature sensor trim value (set a proper value + * when one is determined for Baikal-T1 SoC). + * @PVT_TRIM_TEMP: Maximum temperature encoded by the trim factor. + * @PVT_TRIM_STEP: Temperature stride corresponding to the trim value. + * @PVT_TOUT_MIN: Minimal timeout between samples in nanoseconds. + * @PVT_TOUT_DEF: Default data measurements timeout. In case if alarms are + * activated the PVT IRQ is enabled to be raised after each + * conversion in order to have the thresholds checked and the + * converted value cached. Too frequent conversions may cause + * the system CPU overload. Lets set the 50ms delay between + * them by default to prevent this. + */ +#define PVT_TEMP_MIN -48380L +#define PVT_TEMP_MAX 147438L +#define PVT_TEMP_CHS 1 +#define PVT_VOLT_MIN 620L +#define PVT_VOLT_MAX 1168L +#define PVT_VOLT_CHS 4 +#define PVT_DATA_MIN 0 +#define PVT_DATA_MAX (PVT_DATA_DATA_MASK >> PVT_DATA_DATA_FLD) +#define PVT_TRIM_MIN 0 +#define PVT_TRIM_MAX (PVT_CTRL_TRIM_MASK >> PVT_CTRL_TRIM_FLD) +#define PVT_TRIM_TEMP 7130 +#define PVT_TRIM_STEP (PVT_TRIM_TEMP / PVT_TRIM_MAX) +#define PVT_TRIM_DEF 0 +#define PVT_TOUT_MIN (NSEC_PER_SEC / 3000) +#if defined(CONFIG_SENSORS_BT1_PVT_ALARMS) +# define PVT_TOUT_DEF 60000 +#else +# define PVT_TOUT_DEF 0 +#endif + +/* + * enum pvt_sensor_type - Baikal-T1 PVT sensor types (correspond to each PVT + * sampling mode) + * @PVT_SENSOR*: helpers to traverse the sensors in loops. + * @PVT_TEMP: PVT Temperature sensor. + * @PVT_VOLT: PVT Voltage sensor. + * @PVT_LVT: PVT Low-Voltage threshold sensor. + * @PVT_HVT: PVT High-Voltage threshold sensor. + * @PVT_SVT: PVT Standard-Voltage threshold sensor. + */ +enum pvt_sensor_type { + PVT_SENSOR_FIRST, + PVT_TEMP = PVT_SENSOR_FIRST, + PVT_VOLT, + PVT_LVT, + PVT_HVT, + PVT_SVT, + PVT_SENSOR_LAST = PVT_SVT, + PVT_SENSORS_NUM +}; + +/* + * enum pvt_clock_type - Baikal-T1 PVT clocks. + * @PVT_CLOCK_APB: APB clock. + * @PVT_CLOCK_REF: PVT reference clock. + */ +enum pvt_clock_type { + PVT_CLOCK_APB, + PVT_CLOCK_REF, + PVT_CLOCK_NUM +}; + +/* + * struct pvt_sensor_info - Baikal-T1 PVT sensor informational structure + * @channel: Sensor channel ID. + * @label: hwmon sensor label. + * @mode: PVT mode corresponding to the channel. + * @thres_base: upper and lower threshold values of the sensor. + * @thres_sts_lo: low threshold status bitfield. + * @thres_sts_hi: high threshold status bitfield. + * @type: Sensor type. + * @attr_min_alarm: Min alarm attribute ID. + * @attr_min_alarm: Max alarm attribute ID. + */ +struct pvt_sensor_info { + int channel; + const char *label; + u32 mode; + unsigned long thres_base; + u32 thres_sts_lo; + u32 thres_sts_hi; + enum hwmon_sensor_types type; + u32 attr_min_alarm; + u32 attr_max_alarm; +}; + +#define PVT_SENSOR_INFO(_ch, _label, _type, _mode, _thres) \ + { \ + .channel = _ch, \ + .label = _label, \ + .mode = PVT_CTRL_MODE_ ##_mode, \ + .thres_base = PVT_ ##_thres, \ + .thres_sts_lo = PVT_INTR_ ##_thres## _LO, \ + .thres_sts_hi = PVT_INTR_ ##_thres## _HI, \ + .type = _type, \ + .attr_min_alarm = _type## _min, \ + .attr_max_alarm = _type## _max, \ + } + +/* + * struct pvt_cache - PVT sensors data cache + * @data: data cache in raw format. + * @thres_sts_lo: low threshold status saved on the previous data conversion. + * @thres_sts_hi: high threshold status saved on the previous data conversion. + * @data_seqlock: cached data seq-lock. + * @conversion: data conversion completion. + */ +struct pvt_cache { + u32 data; +#if defined(CONFIG_SENSORS_BT1_PVT_ALARMS) + seqlock_t data_seqlock; + u32 thres_sts_lo; + u32 thres_sts_hi; +#else + struct completion conversion; +#endif +}; + +/* + * struct pvt_hwmon - Baikal-T1 PVT private data + * @dev: device structure of the PVT platform device. + * @hwmon: hwmon device structure. + * @regs: pointer to the Baikal-T1 PVT registers region. + * @irq: PVT events IRQ number. + * @clks: Array of the PVT clocks descriptor (APB/ref clocks). + * @ref_clk: Pointer to the reference clocks descriptor. + * @iface_mtx: Generic interface mutex (used to lock the alarm registers + * when the alarms enabled, or the data conversion interface + * if alarms are disabled). + * @sensor: current PVT sensor the data conversion is being performed for. + * @cache: data cache descriptor. + */ +struct pvt_hwmon { + struct device *dev; + struct device *hwmon; + + void __iomem *regs; + int irq; + + struct clk_bulk_data clks[PVT_CLOCK_NUM]; + + struct mutex iface_mtx; + enum pvt_sensor_type sensor; + struct pvt_cache cache[PVT_SENSORS_NUM]; +}; + +/* + * struct pvt_poly_term - a term descriptor of the PVT data translation + * polynomial + * @deg: degree of the term. + * @coef: multiplication factor of the term. + * @divider: distributed divider per each degree. + * @divider_leftover: divider leftover, which couldn't be redistributed. + */ +struct pvt_poly_term { + unsigned int deg; + long coef; + long divider; + long divider_leftover; +}; + +/* + * struct pvt_poly - PVT data translation polynomial descriptor + * @total_divider: total data divider. + * @terms: polynomial terms up to a free one. + */ +struct pvt_poly { + long total_divider; + struct pvt_poly_term terms[]; +}; + +#endif /* __HWMON_BT1_PVT_H__ */ |