Re: [PATCH v2 2/6] thermal: brcmstb_thermal: Prepare to support a different process

[Florian Fainelli <f.fainelli@gmail.com>]

On 1/9/20 1:17 PM, Daniel Lezcano wrote:
> On 11/12/2019 21:31, Florian Fainelli wrote:
>> The driver is currently assuming that it is operating with a 28nm
>> process chip, which has a specific formula to convert temperature to a
>> code and vice versa. Update the code to support providing two key
>> values: offset and multiplier to derive the correct formulas.
>>
>> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
>> ---
>>  drivers/thermal/broadcom/brcmstb_thermal.c | 54 ++++++++++++++++------
>>  1 file changed, 39 insertions(+), 15 deletions(-)
>>
>> diff --git a/drivers/thermal/broadcom/brcmstb_thermal.c b/drivers/thermal/broadcom/brcmstb_thermal.c
>> index 680f1a070606..68f89f7c7e7f 100644
>> --- a/drivers/thermal/broadcom/brcmstb_thermal.c
>> +++ b/drivers/thermal/broadcom/brcmstb_thermal.c
>> @@ -102,18 +102,27 @@ static struct avs_tmon_trip avs_tmon_trips[] = {
>>  	},
>>  };
>>  
>> +struct brcmstb_thermal_params {
>> +	unsigned int offset;
>> +	unsigned int mult;
>> +};
>> +
>>  struct brcmstb_thermal_priv {
>>  	void __iomem *tmon_base;
>>  	struct device *dev;
>>  	struct thermal_zone_device *thermal;
>> +	/* Process specific thermal parameters used for calculations */
>> +	struct brcmstb_thermal_params temp_params;
>>  };
>>  
>>  /* Convert a HW code to a temperature reading (millidegree celsius) */
>> -static inline int avs_tmon_code_to_temp(struct thermal_zone_device *tz,
>> +static inline int avs_tmon_code_to_temp(struct brcmstb_thermal_priv *priv,
>>  					u32 code)
>>  {
>> -	return (AVS_TMON_TEMP_OFFSET -
>> -		(int)((code & AVS_TMON_TEMP_MAX) * AVS_TMON_TEMP_SLOPE));
>> +	int offset = priv->temp_params.offset;
>> +	int mult = priv->temp_params.mult;
>> +
>> +	return (offset - (int)((code & AVS_TMON_TEMP_MASK) * mult));
>>  }
>>  
>>  /*
>> @@ -122,21 +131,22 @@ static inline int avs_tmon_code_to_temp(struct thermal_zone_device *tz,
>>   * @temp: temperature to convert
>>   * @low: if true, round toward the low side
>>   */
>> -static inline u32 avs_tmon_temp_to_code(struct thermal_zone_device *tz,
>> +static inline u32 avs_tmon_temp_to_code(struct brcmstb_thermal_priv *priv,
>>  					int temp, bool low)
>>  {
>> +	int offset = priv->temp_params.offset;
>> +	int mult = priv->temp_params.mult;
>> +
>>  	if (temp < AVS_TMON_TEMP_MIN)
>> -		return AVS_TMON_TEMP_MAX;	/* Maximum code value */
>> +		return AVS_TMON_TEMP_MASK;	/* Maximum code value */
> 
> Why this change?

No reason to change, thanks.

> 
>>  
>> -	if (temp >= AVS_TMON_TEMP_OFFSET)
>> +	if (temp >= offset)
>>  		return 0;	/* Minimum code value */
>>  
>>  	if (low)
>> -		return (u32)(DIV_ROUND_UP(AVS_TMON_TEMP_OFFSET - temp,
>> -					  AVS_TMON_TEMP_SLOPE));
>> +		return (u32)(DIV_ROUND_UP(offset - temp, mult));
>>  	else
>> -		return (u32)((AVS_TMON_TEMP_OFFSET - temp) /
>> -			      AVS_TMON_TEMP_SLOPE);
>> +		return (u32)((offset - temp) / mult);
>>  }
>>  
>>  static int brcmstb_get_temp(void *data, int *temp)
>> @@ -154,7 +164,7 @@ static int brcmstb_get_temp(void *data, int *temp)
>>  
>>  	val = (val & AVS_TMON_STATUS_data_msk) >> AVS_TMON_STATUS_data_shift;
>>  
>> -	t = avs_tmon_code_to_temp(priv->thermal, val);
>> +	t = avs_tmon_code_to_temp(priv, val);
>>  	if (t < 0)
>>  		*temp = 0;
>>  	else
>> @@ -188,7 +198,7 @@ static int avs_tmon_get_trip_temp(struct brcmstb_thermal_priv *priv,
>>  	val &= trip->reg_msk;
>>  	val >>= trip->reg_shift;
>>  
>> -	return avs_tmon_code_to_temp(priv->thermal, val);
>> +	return avs_tmon_code_to_temp(priv, val);
>>  }
>>  
>>  static void avs_tmon_set_trip_temp(struct brcmstb_thermal_priv *priv,
>> @@ -201,7 +211,7 @@ static void avs_tmon_set_trip_temp(struct brcmstb_thermal_priv *priv,
>>  	dev_dbg(priv->dev, "set temp %d to %d\n", type, temp);
>>  
>>  	/* round toward low temp for the low interrupt */
>> -	val = avs_tmon_temp_to_code(priv->thermal, temp,
>> +	val = avs_tmon_temp_to_code(priv, temp,
>>  				    type == TMON_TRIP_TYPE_LOW);
>>  
>>  	val <<= trip->reg_shift;
>> @@ -218,7 +228,7 @@ static int avs_tmon_get_intr_temp(struct brcmstb_thermal_priv *priv)
>>  	u32 val;
>>  
>>  	val = __raw_readl(priv->tmon_base + AVS_TMON_TEMP_INT_CODE);
>> -	return avs_tmon_code_to_temp(priv->thermal, val);
>> +	return avs_tmon_code_to_temp(priv, val);
>>  }
>>  
>>  static irqreturn_t brcmstb_tmon_irq_thread(int irq, void *data)
>> @@ -282,19 +292,32 @@ static const struct thermal_zone_of_device_ops of_ops = {
>>  	.set_trips	= brcmstb_set_trips,
>>  };
>>  
>> +static const struct brcmstb_thermal_params brcmstb_28nm_params = {
>> +	.offset	= 410040,
>> +	.mult	= 487,
>> +};
>> +
>>  static const struct of_device_id brcmstb_thermal_id_table[] = {
>> -	{ .compatible = "brcm,avs-tmon" },
>> +	{ .compatible = "brcm,avs-tmon", .data = &brcmstb_28nm_params },
>>  	{},
>>  };
>>  MODULE_DEVICE_TABLE(of, brcmstb_thermal_id_table);
>>  
>>  static int brcmstb_thermal_probe(struct platform_device *pdev)
>>  {
>> +	const struct brcmstb_thermal_params *params;
>> +	const struct of_device_id *of_id = NULL;
>>  	struct thermal_zone_device *thermal;
>>  	struct brcmstb_thermal_priv *priv;
>>  	struct resource *res;
>>  	int irq, ret;
>>  
>> +	of_id = of_match_node(brcmstb_thermal_id_table, pdev->dev.of_node);
>> +	if (!of_id || !of_id->data)
>> +		return -EINVAL;
> 
> of_device_get_match_data(&pdev->dev) ?

Yes.

> 
>> +	params = of_id->data;
>> +
>>  	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
>>  	if (!priv)
>>  		return -ENOMEM;
>> @@ -304,6 +327,7 @@ static int brcmstb_thermal_probe(struct platform_device *pdev)
>>  	if (IS_ERR(priv->tmon_base))
>>  		return PTR_ERR(priv->tmon_base);
>>  
>> +	memcpy(&priv->temp_params, params, sizeof(priv->temp_params));
> 
> Do you really need a copy here? Why not convert to a pointer and assign it?

I would rather not reference data that is possibly __initconst or
__initdata, this is not the case here but I have been burned by this
before, I will change it to a pointer.

Thanks!
-- 
Florian