Re: [PATCH v2 2/2] phy: ti: j721e-wiz: Implement DisplayPort mode to the wiz driver

[Kishon Vijay Abraham I]

Hi Jyri,

On 08/01/20 2:00 PM, Jyri Sarha wrote:
> For DisplayPort use we need to set WIZ_CONFIG_LANECTL register's
> P_STANDARD_MODE bits to "mode 3". In the DisplayPort use also the
> P_ENABLE bits of the same register are set to P_ENABLE instead of
> P_ENABLE_FORCE, so that the DisplayPort driver can enable and disable
> the lane as needed. The DisplayPort mode is selected according to
> "cdns,phy-type"-properties found in link subnodes under the managed
> serdes (see "ti,sierra-phy-t0" and "ti,j721e-serdes-10g" devicetree
> bindings for details). All other values of "cdns,phy-type"-property
> but PHY_TYPE_DP will set P_STANDARD_MODE bits to 0 and P_ENABLE bits
> to force enable.
> 
> Signed-off-by: Jyri Sarha <jsarha@xxxxxx>
> ---
>  drivers/phy/ti/phy-j721e-wiz.c | 59 +++++++++++++++++++++++++++++++---
>  1 file changed, 55 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/phy/ti/phy-j721e-wiz.c b/drivers/phy/ti/phy-j721e-wiz.c
> index b5f6019e5c7d..22bc04846cdb 100644
> --- a/drivers/phy/ti/phy-j721e-wiz.c
> +++ b/drivers/phy/ti/phy-j721e-wiz.c
> @@ -20,6 +20,7 @@
>  #include <linux/pm_runtime.h>
>  #include <linux/regmap.h>
>  #include <linux/reset-controller.h>
> +#include <dt-bindings/phy/phy.h>
>  
>  #define WIZ_SERDES_CTRL		0x404
>  #define WIZ_SERDES_TOP_CTRL	0x408
> @@ -78,6 +79,8 @@ static const struct reg_field p_enable[WIZ_MAX_LANES] = {
>  	REG_FIELD(WIZ_LANECTL(3), 30, 31),
>  };
>  
> +enum p_enable { P_ENABLE = 2, P_ENABLE_FORCE = 1, P_ENABLE_DISABLE = 0 };
> +
>  static const struct reg_field p_align[WIZ_MAX_LANES] = {
>  	REG_FIELD(WIZ_LANECTL(0), 29, 29),
>  	REG_FIELD(WIZ_LANECTL(1), 29, 29),
> @@ -220,6 +223,7 @@ struct wiz {
>  	struct reset_controller_dev wiz_phy_reset_dev;
>  	struct gpio_desc	*gpio_typec_dir;
>  	int			typec_dir_delay;
> +	u32 lane_phy_type[WIZ_MAX_LANES];
>  };
>  
>  static int wiz_reset(struct wiz *wiz)
> @@ -242,12 +246,17 @@ static int wiz_reset(struct wiz *wiz)
>  static int wiz_mode_select(struct wiz *wiz)
>  {
>  	u32 num_lanes = wiz->num_lanes;
> +	enum wiz_lane_standard_mode mode;
>  	int ret;
>  	int i;
>  
>  	for (i = 0; i < num_lanes; i++) {
> -		ret = regmap_field_write(wiz->p_standard_mode[i],
> -					 LANE_MODE_GEN4);
> +		if (wiz->lane_phy_type[i] == PHY_TYPE_DP)
> +			mode = LANE_MODE_GEN1;
> +		else
> +			mode = LANE_MODE_GEN4;
> +
> +		ret = regmap_field_write(wiz->p_standard_mode[i], mode);
>  		if (ret)
>  			return ret;
>  	}
> @@ -707,7 +716,7 @@ static int wiz_phy_reset_assert(struct reset_controller_dev *rcdev,
>  		return ret;
>  	}
>  
> -	ret = regmap_field_write(wiz->p_enable[id - 1], false);
> +	ret = regmap_field_write(wiz->p_enable[id - 1], P_ENABLE_DISABLE);
>  	return ret;
>  }
>  
> @@ -734,7 +743,11 @@ static int wiz_phy_reset_deassert(struct reset_controller_dev *rcdev,
>  		return ret;
>  	}
>  
> -	ret = regmap_field_write(wiz->p_enable[id - 1], true);
> +	if (wiz->lane_phy_type[id - 1] == PHY_TYPE_DP)
> +		ret = regmap_field_write(wiz->p_enable[id - 1], P_ENABLE);
> +	else
> +		ret = regmap_field_write(wiz->p_enable[id - 1], P_ENABLE_FORCE);
> +
>  	return ret;
>  }
>  
> @@ -761,6 +774,40 @@ static const struct of_device_id wiz_id_table[] = {
>  };
>  MODULE_DEVICE_TABLE(of, wiz_id_table);
>  
> +static int wiz_get_lane_phy_types(struct device *dev, struct wiz *wiz)
> +{
> +	struct device_node *serdes, *subnode;
> +
> +	serdes = of_get_child_by_name(dev->of_node, "serdes");
> +	if (!serdes) {
> +		dev_err(dev, "%s: Getting \"serdes\"-node failed\n", __func__);
> +		return -EINVAL;
> +	}
> +
> +	for_each_child_of_node(serdes, subnode) {
> +		u32 reg, num_lanes = 1, phy_type = PHY_NONE;
> +		int ret, i;
> +
> +		ret = of_property_read_u32(subnode, "reg", &reg);
> +		if (ret) {
> +			dev_err(dev,
> +				"%s: Reading \"reg\" from \"%s\" failed: %d\n",
> +				__func__, subnode->name, ret);
> +			return ret;
> +		}
> +		of_property_read_u32(subnode, "cdns,num-lanes", &num_lanes);
> +		of_property_read_u32(subnode, "cdns,phy-type", &phy_type);
This would require the Torrent bindings to be Reviewed and Acked.

Thanks
Kishon