[PATCH v4 4/5] soc: ti: pruss: Add helper functions to set GPI mode, MII_RT_event and XFR

[Roger Quadros]

On 13/03/2023 13:11, MD Danish Anwar wrote:
> From: Suman Anna <s-anna at ti.com>
> 
> The PRUSS CFG module is represented as a syscon node and is currently
> managed by the PRUSS platform driver. Add easy accessor functions to set
> GPI mode, MII_RT event enable/disable and XFR (XIN XOUT) enable/disable
> to enable the PRUSS Ethernet usecase. These functions reuse the generic
> pruss_cfg_update() API function.
> 
> Signed-off-by: Suman Anna <s-anna at ti.com>
> Co-developed-by: Grzegorz Jaszczyk <grzegorz.jaszczyk at linaro.org>
> Signed-off-by: Grzegorz Jaszczyk <grzegorz.jaszczyk at linaro.org>
> Signed-off-by: Puranjay Mohan <p-mohan at ti.com>
> Signed-off-by: MD Danish Anwar <danishanwar at ti.com>
> ---
>  drivers/soc/ti/pruss.c           | 60 ++++++++++++++++++++++++++++++++
>  include/linux/remoteproc/pruss.h | 22 ++++++++++++
>  2 files changed, 82 insertions(+)
> 
> diff --git a/drivers/soc/ti/pruss.c b/drivers/soc/ti/pruss.c
> index 26d8129b515c..2f04b7922ddb 100644
> --- a/drivers/soc/ti/pruss.c
> +++ b/drivers/soc/ti/pruss.c
> @@ -203,6 +203,66 @@ static int pruss_cfg_update(struct pruss *pruss, unsigned int reg,
>  	return regmap_update_bits(pruss->cfg_regmap, reg, mask, val);
>  }
>  
> +/**
> + * pruss_cfg_gpimode() - set the GPI mode of the PRU
> + * @pruss: the pruss instance handle
> + * @pru_id: id of the PRU core within the PRUSS
> + * @mode: GPI mode to set
> + *
> + * Sets the GPI mode for a given PRU by programming the
> + * corresponding PRUSS_CFG_GPCFGx register
> + *
> + * Return: 0 on success, or an error code otherwise
> + */
> +int pruss_cfg_gpimode(struct pruss *pruss, enum pruss_pru_id pru_id,
> +		      enum pruss_gpi_mode mode)
> +{
> +	if (pru_id < 0 || pru_id >= PRUSS_NUM_PRUS)
> +		return -EINVAL;
> +
> +	if (mode < 0 || mode > PRUSS_GPI_MODE_MAX)
> +		return -EINVAL;
> +
> +	return pruss_cfg_update(pruss, PRUSS_CFG_GPCFG(pru_id),
> +				PRUSS_GPCFG_PRU_GPI_MODE_MASK,
> +				mode << PRUSS_GPCFG_PRU_GPI_MODE_SHIFT);
> +}
> +EXPORT_SYMBOL_GPL(pruss_cfg_gpimode);
> +
> +/**
> + * pruss_cfg_miirt_enable() - Enable/disable MII RT Events
> + * @pruss: the pruss instance
> + * @enable: enable/disable
> + *
> + * Enable/disable the MII RT Events for the PRUSS.
> + *
> + * Return: 0 on success, or an error code otherwise
> + */
> +int pruss_cfg_miirt_enable(struct pruss *pruss, bool enable)
> +{
> +	u32 set = enable ? PRUSS_MII_RT_EVENT_EN : 0;
> +
> +	return pruss_cfg_update(pruss, PRUSS_CFG_MII_RT,
> +				PRUSS_MII_RT_EVENT_EN, set);
> +}
> +EXPORT_SYMBOL_GPL(pruss_cfg_miirt_enable);
> +
> +/**
> + * pruss_cfg_xfr_enable() - Enable/disable XIN XOUT shift functionality
> + * @pruss: the pruss instance
> + * @enable: enable/disable
> + * @mask: Mask for PRU / RTU

You should not expect the user to provide the mask but only
the core type e.g. 

enum pru_type {
        PRU_TYPE_PRU = 0,
        PRU_TYPE_RTU,
        PRU_TYPE_TX_PRU,
        PRU_TYPE_MAX,
};

Then you figure out the mask in the function.
Also check for invalid pru_type and return error if so.

> + *
> + * Return: 0 on success, or an error code otherwise
> + */
> +int pruss_cfg_xfr_enable(struct pruss *pruss, bool enable, u32 mask)

re-arrange so it is (struct pruss, enum pru_type, bool enable)

> +{
> +	u32 set = enable ? mask : 0;
> +
> +	return pruss_cfg_update(pruss, PRUSS_CFG_SPP, mask, set);
> +}
> +EXPORT_SYMBOL_GPL(pruss_cfg_xfr_enable);
> +
>  static void pruss_of_free_clk_provider(void *data)
>  {
>  	struct device_node *clk_mux_np = data;
> diff --git a/include/linux/remoteproc/pruss.h b/include/linux/remoteproc/pruss.h
> index 12ef10b9fe9a..51a3eedd2be6 100644
> --- a/include/linux/remoteproc/pruss.h
> +++ b/include/linux/remoteproc/pruss.h
> @@ -101,6 +101,7 @@ enum pruss_gpi_mode {
>  	PRUSS_GPI_MODE_PARALLEL,
>  	PRUSS_GPI_MODE_28BIT_SHIFT,
>  	PRUSS_GPI_MODE_MII,
> +	PRUSS_GPI_MODE_MAX,

This could have come as part of patch 3.

>  };
>  
>  /**
> @@ -165,6 +166,10 @@ int pruss_request_mem_region(struct pruss *pruss, enum pruss_mem mem_id,
>  			     struct pruss_mem_region *region);
>  int pruss_release_mem_region(struct pruss *pruss,
>  			     struct pruss_mem_region *region);
> +int pruss_cfg_gpimode(struct pruss *pruss, enum pruss_pru_id pru_id,
> +		      enum pruss_gpi_mode mode);
> +int pruss_cfg_miirt_enable(struct pruss *pruss, bool enable);
> +int pruss_cfg_xfr_enable(struct pruss *pruss, bool enable, u32 mask);
>  
>  #else
>  
> @@ -188,6 +193,23 @@ static inline int pruss_release_mem_region(struct pruss *pruss,
>  	return -EOPNOTSUPP;
>  }
>  
> +static inline int pruss_cfg_gpimode(struct pruss *pruss,
> +				    enum pruss_pru_id pru_id,
> +				    enum pruss_gpi_mode mode)
> +{
> +	return ERR_PTR(-EOPNOTSUPP);
> +}
> +
> +static inline int pruss_cfg_miirt_enable(struct pruss *pruss, bool enable)
> +{
> +	return ERR_PTR(-EOPNOTSUPP);
> +}
> +
> +static inline int pruss_cfg_xfr_enable(struct pruss *pruss, bool enable, u32 mask)
> +{
> +	return ERR_PTR(-EOPNOTSUPP);
> +}
> +
>  #endif /* CONFIG_TI_PRUSS */
>  
>  #if IS_ENABLED(CONFIG_PRU_REMOTEPROC)

cheers,
-roger