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

[Daniel Lezcano]

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@xxxxxxxxx>
> ---
>  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?

>  
> -	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) ?

> +	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?

>  	priv->dev = &pdev->dev;
>  	platform_set_drvdata(pdev, priv);
>  
> 


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