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Message-ID: <644ae31f-3829-49bc-942e-4b5e87aed140@quicinc.com>
Date:   Mon, 10 Jul 2023 18:54:12 +0530
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Subject: Re: [PATCH 2/6] thermal/drivers/tsens: Add TSENS enable and
 calibration support for V2
Content-Language: en-US
To:     Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        <agross@kernel.org>, <andersson@kernel.org>,
        <konrad.dybcio@linaro.org>, <amitk@kernel.org>,
        <thara.gopinath@gmail.com>, <rafael@kernel.org>,
        <daniel.lezcano@linaro.org>, <rui.zhang@intel.com>,
        <robh+dt@kernel.org>, <krzysztof.kozlowski+dt@linaro.org>,
        <conor+dt@kernel.org>, <linux-arm-msm@vger.kernel.org>,
        <linux-pm@vger.kernel.org>, <devicetree@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
CC:     <quic_varada@quicinc.com>
References: <20230710103735.1375847-1-quic_ipkumar@quicinc.com>
 <20230710103735.1375847-3-quic_ipkumar@quicinc.com>
 <cf2cae88-e226-8df1-6c4f-543b683cbc8c@linaro.org>
 <443434f2-dba8-23cc-b0ac-f620ac394192@linaro.org>
From:   Praveenkumar I <quic_ipkumar@quicinc.com>
In-Reply-To: <443434f2-dba8-23cc-b0ac-f620ac394192@linaro.org>
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On 7/10/2023 4:52 PM, Dmitry Baryshkov wrote:
> On 10/07/2023 14:19, Dmitry Baryshkov wrote:
>> On 10/07/2023 13:37, Praveenkumar I wrote:
>>> SoCs without RPM have to enable sensors and calibrate from the kernel.
>>> Though TSENS IP supports 16 sensors, not all are used. So added
>>> sensors_to_en in tsens data help enable the relevant sensors.
>>>
>>> Added new calibration function for V2 as the tsens.c calib function
>>> only supports V1.
>>>
>>> Signed-off-by: Praveenkumar I <quic_ipkumar@quicinc.com>
>>> ---
>>>   drivers/thermal/qcom/tsens-v2.c | 116 
>>> ++++++++++++++++++++++++++++++++
>>>   drivers/thermal/qcom/tsens.c    |  37 +++++++++-
>>>   drivers/thermal/qcom/tsens.h    |  56 +++++++++++++++
>>>   3 files changed, 208 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/thermal/qcom/tsens-v2.c 
>>> b/drivers/thermal/qcom/tsens-v2.c
>>> index 29a61d2d6ca3..db48b1d95348 100644
>>> --- a/drivers/thermal/qcom/tsens-v2.c
>>> +++ b/drivers/thermal/qcom/tsens-v2.c
>>> @@ -6,11 +6,20 @@
>>>   #include <linux/bitops.h>
>>>   #include <linux/regmap.h>
>>> +#include <linux/nvmem-consumer.h>
>>>   #include "tsens.h"
>>>   /* ----- SROT ------ */
>>>   #define SROT_HW_VER_OFF    0x0000
>>>   #define SROT_CTRL_OFF        0x0004
>>> +#define SROT_MEASURE_PERIOD    0x0008
>>> +#define SROT_Sn_CONVERSION    0x0060
>>> +#define V2_SHIFT_DEFAULT    0x0003
>>> +#define V2_SLOPE_DEFAULT    0x0cd0
>>> +#define V2_CZERO_DEFAULT    0x016a
>>> +#define ONE_PT_SLOPE        0x0cd0
>>> +#define TWO_PT_SHIFTED_GAIN    921600
>>> +#define ONE_PT_CZERO_CONST    94
>>>   /* ----- TM ------ */
>>>   #define TM_INT_EN_OFF            0x0004
>>> @@ -59,6 +68,16 @@ static const struct reg_field 
>>> tsens_v2_regfields[MAX_REGFIELDS] = {
>>>       /* CTRL_OFF */
>>>       [TSENS_EN]     = REG_FIELD(SROT_CTRL_OFF,    0,  0),
>>>       [TSENS_SW_RST] = REG_FIELD(SROT_CTRL_OFF,    1,  1),
>>> +    [SENSOR_EN]    = REG_FIELD(SROT_CTRL_OFF,    3,  18),
>>> +    [CODE_OR_TEMP] = REG_FIELD(SROT_CTRL_OFF,    21, 21),
>>> +
>>> +    /* MAIN_MEASURE_PERIOD */
>>> +    [MAIN_MEASURE_PERIOD] = REG_FIELD(SROT_MEASURE_PERIOD, 0, 7),
>>> +
>>> +    /* Sn Conversion */
>>> +    REG_FIELD_FOR_EACH_SENSOR16(SHIFT, SROT_Sn_CONVERSION, 23, 24),
>>> +    REG_FIELD_FOR_EACH_SENSOR16(SLOPE, SROT_Sn_CONVERSION, 10, 22),
>>> +    REG_FIELD_FOR_EACH_SENSOR16(CZERO, SROT_Sn_CONVERSION, 0, 9),
>>>       /* ----- TM ------ */
>>>       /* INTERRUPT ENABLE */
>>> @@ -104,6 +123,103 @@ static const struct reg_field 
>>> tsens_v2_regfields[MAX_REGFIELDS] = {
>>>       [TRDY] = REG_FIELD(TM_TRDY_OFF, 0, 0),
>>>   };
>>> +static int tsens_v2_calibration(struct tsens_priv *priv)
>>> +{
>>> +    struct device *dev = priv->dev;
>>> +    u32 mode, base0, base1;
>>> +    u32 slope, czero;
>>> +    char name[15];
>>> +    int i, j, ret;
>>> +
>>> +    if (priv->num_sensors > MAX_SENSORS)
>>> +        return -EINVAL;
>>> +
>>> +    ret = nvmem_cell_read_variable_le_u32(priv->dev, "mode", &mode);
>>> +    if (ret == -ENOENT)
>>> +        dev_warn(priv->dev, "Calibration data not present in DT\n");
>>> +    if (ret < 0)
>>> +        return ret;
>>> +
>>> +    dev_dbg(priv->dev, "calibration mode is %d\n", mode);
>>> +
>>> +    ret = nvmem_cell_read_variable_le_u32(priv->dev, "base0", &base0);
>>> +    if (ret < 0)
>>> +        return ret;
>>> +
>>> +    ret = nvmem_cell_read_variable_le_u32(priv->dev, "base1", &base1);
>>> +    if (ret < 0)
>>> +        return ret;
>>> +
>>> +    /* Read offset values and allocate SHIFT, SLOPE & CZERO regmap 
>>> for enabled sensors */
>>> +    for (i = 0; i < priv->num_sensors; i++) {
>>> +        if (!(priv->sensors_to_en & (0x1 << i)))
>>> +            continue;
>>> +
>>> +        ret = snprintf(name, sizeof(name), "s%d_offset", 
>>> priv->sensor[i].hw_id);
>>> +        if (ret < 0)
>>> +            return ret;
>>> +
>>> +        ret = nvmem_cell_read_variable_le_u32(priv->dev, name, 
>>> &priv->sensor[i].offset);
>>> +        if (ret)
>>> +            return ret;
>>> +
>>> +        for (j = SHIFT_0; j <= CZERO_0; j++) {
>>> +            int idx = (i * 3) + j;
>>> +
>>> +            priv->rf[idx] = devm_regmap_field_alloc(dev, 
>>> priv->srot_map,
>>> +                                priv->fields[idx]);
>>> +            if (IS_ERR(priv->rf[idx]))
>>> +                return PTR_ERR(priv->rf[idx]);
>>
>> I think, allocating data structures for 48 regfields, which are 
>> written just once, to be an overkill.
>>
>>> +        }
>>> +    }
>>> +
>>> +    /* Based on calib mode, program SHIFT, SLOPE and CZERO for 
>>> enabled sensors */
>>> +    switch (mode) {
>>> +    case TWO_PT_CALIB:
>>> +        slope = (TWO_PT_SHIFTED_GAIN / (base1 - base0));
>>> +
>>> +        for (i = 0; i < priv->num_sensors; i++) {
>>> +            if (!(priv->sensors_to_en & (0x1 << i)))
>>> +                continue;
>>> +
>>> +            int idx = i * 3;
>>> +
>>> +            czero = (base0 + priv->sensor[i].offset - ((base1 - 
>>> base0) / 3));
>>> +            regmap_field_write(priv->rf[SHIFT_0 + idx], 
>>> V2_SHIFT_DEFAULT);
>>> +            regmap_field_write(priv->rf[SLOPE_0 + idx], slope);
>>> +            regmap_field_write(priv->rf[CZERO_0 + idx], czero);
>>> +        }
>>> +        fallthrough;
>>> +    case ONE_PT_CALIB2:
>>> +        for (i = 0; i < priv->num_sensors; i++) {
>>> +            if (!(priv->sensors_to_en & (0x1 << i)))
>>> +                continue;
>>> +
>>> +            int idx = i * 3;
>>> +
>>> +            czero = base0 + priv->sensor[i].offset - 
>>> ONE_PT_CZERO_CONST;
>>> +            regmap_field_write(priv->rf[SHIFT_0 + idx], 
>>> V2_SHIFT_DEFAULT);
>>> +            regmap_field_write(priv->rf[SLOPE_0 + idx], ONE_PT_SLOPE);
>>> +            regmap_field_write(priv->rf[CZERO_0 + idx], czero);
>>> +        }
>>> +        break;
>>> +    default:
>>> +        dev_dbg(priv->dev, "calibrationless mode\n");
>>> +        for (i = 0; i < priv->num_sensors; i++) {
>>> +            if (!(priv->sensors_to_en & (0x1 << i)))
>>> +                continue;
>>> +
>>> +            int idx = i * 3;
>>> +
>>> +            regmap_field_write(priv->rf[SHIFT_0 + idx], 
>>> V2_SHIFT_DEFAULT);
>>> +            regmap_field_write(priv->rf[SLOPE_0 + idx], 
>>> V2_SLOPE_DEFAULT);
>>> +            regmap_field_write(priv->rf[CZERO_0 + idx], 
>>> V2_CZERO_DEFAULT);
>>> +        }
>>> +    }
>>
>> This code iterates over the sensors field several times. Please 
>> consider extracting a function that handles all setup for a single 
>> sensor, then calling it in a loop (I should probably do the same for 
>> tsens-v0/v1 too).
>>
>>> +
>>> +    return 0;
>>> +}
>>> +
>>>   static const struct tsens_ops ops_generic_v2 = {
>>>       .init        = init_common,
>>>       .get_temp    = get_temp_tsens_valid,
>>> diff --git a/drivers/thermal/qcom/tsens.c 
>>> b/drivers/thermal/qcom/tsens.c
>>> index 98c356acfe98..169690355dad 100644
>>> --- a/drivers/thermal/qcom/tsens.c
>>> +++ b/drivers/thermal/qcom/tsens.c
>>> @@ -974,7 +974,7 @@ int __init init_common(struct tsens_priv *priv)
>>>       ret = regmap_field_read(priv->rf[TSENS_EN], &enabled);
>>>       if (ret)
>>>           goto err_put_device;
>>> -    if (!enabled) {
>>> +    if (!enabled && !priv->sensors_to_en) {
>>>           dev_err(dev, "%s: device not enabled\n", __func__);
>>>           ret = -ENODEV;
>>>           goto err_put_device;
>>> @@ -1006,6 +1006,40 @@ int __init init_common(struct tsens_priv *priv)
>>>           goto err_put_device;
>>>       }
>>> +    /* Do TSENS initialization if required */
>>> +    if (priv->sensors_to_en) {
>>
>> Maybe it would be better to explicitly add VER_2_X_NO_RPM and check 
>> it here?
>
> After taking a look at the patch 6, can we just add a separate init() 
> function which will call init_common() and then initialize these fields?
Sure, will add separate init() function in tsens-v2.c
>
>>
>>> +        priv->rf[CODE_OR_TEMP] = devm_regmap_field_alloc(dev, 
>>> priv->srot_map,
>>> + priv->fields[CODE_OR_TEMP]);
>>> +        if (IS_ERR(priv->rf[CODE_OR_TEMP])) {
>>> +            ret = PTR_ERR(priv->rf[CODE_OR_TEMP]);
>>> +            goto err_put_device;
>>> +        }
>>> +
>>> +        priv->rf[MAIN_MEASURE_PERIOD] =
>>> +            devm_regmap_field_alloc(dev, priv->srot_map,
>>> + priv->fields[MAIN_MEASURE_PERIOD]);
>>> +        if (IS_ERR(priv->rf[MAIN_MEASURE_PERIOD])) {
>>> +            ret = PTR_ERR(priv->rf[MAIN_MEASURE_PERIOD]);
>>> +            goto err_put_device;
>>> +        }
>>> +
>>> +        regmap_field_write(priv->rf[TSENS_SW_RST], 0x1);
>>> +
>>> +        /* Update measure period to 2ms */
>>> +        regmap_field_write(priv->rf[MAIN_MEASURE_PERIOD], 0x1);
>>> +
>>> +        /* Enable available sensors */
>>> +        regmap_field_write(priv->rf[SENSOR_EN], priv->sensors_to_en);
>>> +
>>> +        /* Real temperature format */
>>> +        regmap_field_write(priv->rf[CODE_OR_TEMP], 0x1);
>>> +
>>> +        regmap_field_write(priv->rf[TSENS_SW_RST], 0x0);
>>> +
>>> +        /* Enable TSENS */
>>> +        regmap_field_write(priv->rf[TSENS_EN], 0x1);
>>> +    }
>>> +
>>>       /* This loop might need changes if enum regfield_ids is 
>>> reordered */
>>>       for (j = LAST_TEMP_0; j <= UP_THRESH_15; j += 16) {
>>>           for (i = 0; i < priv->feat->max_sensors; i++) {
>>> @@ -1282,6 +1316,7 @@ static int tsens_probe(struct platform_device 
>>> *pdev)
>>>       priv->dev = dev;
>>>       priv->num_sensors = num_sensors;
>>> +    priv->sensors_to_en = data->sensors_to_en;
>>>       priv->ops = data->ops;
>>>       for (i = 0;  i < priv->num_sensors; i++) {
>>>           if (data->hw_ids)
>>> diff --git a/drivers/thermal/qcom/tsens.h 
>>> b/drivers/thermal/qcom/tsens.h
>>> index 2805de1c6827..f8897bc8944e 100644
>>> --- a/drivers/thermal/qcom/tsens.h
>>> +++ b/drivers/thermal/qcom/tsens.h
>>> @@ -168,6 +168,58 @@ enum regfield_ids {
>>>       TSENS_SW_RST,
>>>       SENSOR_EN,
>>>       CODE_OR_TEMP,
>>> +    /* MEASURE_PERIOD */
>>> +    MAIN_MEASURE_PERIOD,
>>> +
>>> +    /* Sn_CONVERSION */
>>> +    SHIFT_0,
>>> +    SLOPE_0,
>>> +    CZERO_0,
>>> +    SHIFT_1,
>>> +    SLOPE_1,
>>> +    CZERO_1,
>>> +    SHIFT_2,
>>> +    SLOPE_2,
>>> +    CZERO_2,
>>> +    SHIFT_3,
>>> +    SLOPE_3,
>>> +    CZERO_3,
>>> +    SHIFT_4,
>>> +    SLOPE_4,
>>> +    CZERO_4,
>>> +    SHIFT_5,
>>> +    SLOPE_5,
>>> +    CZERO_5,
>>> +    SHIFT_6,
>>> +    SLOPE_6,
>>> +    CZERO_6,
>>> +    SHIFT_7,
>>> +    SLOPE_7,
>>> +    CZERO_7,
>>> +    SHIFT_8,
>>> +    SLOPE_8,
>>> +    CZERO_8,
>>> +    SHIFT_9,
>>> +    SLOPE_9,
>>> +    CZERO_9,
>>> +    SHIFT_10,
>>> +    SLOPE_10,
>>> +    CZERO_10,
>>> +    SHIFT_11,
>>> +    SLOPE_11,
>>> +    CZERO_11,
>>> +    SHIFT_12,
>>> +    SLOPE_12,
>>> +    CZERO_12,
>>> +    SHIFT_13,
>>> +    SLOPE_13,
>>> +    CZERO_13,
>>> +    SHIFT_14,
>>> +    SLOPE_14,
>>> +    CZERO_14,
>>> +    SHIFT_15,
>>> +    SLOPE_15,
>>> +    CZERO_15,
>>>       /* ----- TM ------ */
>>>       /* TRDY */
>>> @@ -524,6 +576,7 @@ struct tsens_features {
>>>   /**
>>>    * struct tsens_plat_data - tsens compile-time platform data
>>>    * @num_sensors: Number of sensors supported by platform
>>> + * @sensors_to_en: Sensors to be enabled. Each bit represent a sensor
>>>    * @ops: operations the tsens instance supports
>>>    * @hw_ids: Subset of sensors ids supported by platform, if not 
>>> the first n
>>>    * @feat: features of the IP
>>> @@ -531,6 +584,7 @@ struct tsens_features {
>>>    */
>>>   struct tsens_plat_data {
>>>       const u32        num_sensors;
>>> +    const u16        sensors_to_en;
>>
>> There is already a similar field, hw_ids. Can it be used instead?
>>
>>>       const struct tsens_ops    *ops;
>>>       unsigned int        *hw_ids;
>>>       struct tsens_features    *feat;
>>> @@ -551,6 +605,7 @@ struct tsens_context {
>>>    * struct tsens_priv - private data for each instance of the tsens IP
>>>    * @dev: pointer to struct device
>>>    * @num_sensors: number of sensors enabled on this device
>>> + * @sensors_to_en: sensors to be enabled. Each bit represents a sensor
>>>    * @tm_map: pointer to TM register address space
>>>    * @srot_map: pointer to SROT register address space
>>>    * @tm_offset: deal with old device trees that don't address TM 
>>> and SROT
>>> @@ -569,6 +624,7 @@ struct tsens_context {
>>>   struct tsens_priv {
>>>       struct device            *dev;
>>>       u32                num_sensors;
>>> +    u16                sensors_to_en;
>>>       struct regmap            *tm_map;
>>>       struct regmap            *srot_map;
>>>       u32                tm_offset;
>>
>
--
Thanks,
Praveenkumar