Re: [PATCH] drm/msm/dsi: support CPHY mode for 7nm pll/phy

[Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>]

On 15/02/2021 19:27, Jonathan Marek wrote:
> Add the required changes to support 7nm pll/phy in CPHY mode.
>
> This adds a "qcom,dsi-phy-cphy-mode" property for the PHY node to enable
> the CPHY mode.
>
> Signed-off-by: Jonathan Marek <jonathan@xxxxxxxx>

Other that few comments bellow:

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>

> ---
>   .../devicetree/bindings/display/msm/dsi.txt   |  1 +
>   drivers/gpu/drm/msm/dsi/dsi.c                 | 12 +--
>   drivers/gpu/drm/msm/dsi/dsi.h                 |  6 +-
>   drivers/gpu/drm/msm/dsi/dsi.xml.h             |  2 +
>   drivers/gpu/drm/msm/dsi/dsi_host.c            | 34 +++++--
>   drivers/gpu/drm/msm/dsi/phy/dsi_phy.c         | 49 +++++++++-
>   drivers/gpu/drm/msm/dsi/phy/dsi_phy.h         |  3 +
>   drivers/gpu/drm/msm/dsi/phy/dsi_phy_7nm.c     | 89 ++++++++++++++-----
>   drivers/gpu/drm/msm/dsi/pll/dsi_pll.c         |  4 +-
>   drivers/gpu/drm/msm/dsi/pll/dsi_pll.h         |  5 +-
>   drivers/gpu/drm/msm/dsi/pll/dsi_pll_7nm.c     | 71 +++++++++------
>   11 files changed, 210 insertions(+), 66 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/display/msm/dsi.txt b/Documentation/devicetree/bindings/display/msm/dsi.txt
> index b9a64d3ff184..7ffc86a9816b 100644
> --- a/Documentation/devicetree/bindings/display/msm/dsi.txt
> +++ b/Documentation/devicetree/bindings/display/msm/dsi.txt
> @@ -124,6 +124,7 @@ Required properties:
>   Optional properties:
>   - qcom,dsi-phy-regulator-ldo-mode: Boolean value indicating if the LDO mode PHY
>     regulator is wanted.
> +- qcom,dsi-phy-cphy-mode: Boolean value indicating if CPHY mode is wanted.
>   - qcom,mdss-mdp-transfer-time-us:	Specifies the dsi transfer time for command mode
>   					panels in microseconds. Driver uses this number to adjust
>   					the clock rate according to the expected transfer time.

This should go in a separate patch, shan't it?

> diff --git a/drivers/gpu/drm/msm/dsi/dsi.c b/drivers/gpu/drm/msm/dsi/dsi.c
> index 627048851d99..68d8547f7264 100644
> --- a/drivers/gpu/drm/msm/dsi/dsi.c
> +++ b/drivers/gpu/drm/msm/dsi/dsi.c
> @@ -13,7 +13,7 @@ struct drm_encoder *msm_dsi_get_encoder(struct msm_dsi *msm_dsi)
>   	return msm_dsi->encoder;
>   }
>   
> -static int dsi_get_phy(struct msm_dsi *msm_dsi)
> +static int dsi_get_phy(struct msm_dsi *msm_dsi, bool *cphy_mode)

I see no need to pass the 'cphy_mode' through the bool pointer and back 
to msm_dsi_host_init. What about just putting it into struct msm_dsi?

>   {
>   	struct platform_device *pdev = msm_dsi->pdev;
>   	struct platform_device *phy_pdev;
> @@ -29,6 +29,7 @@ static int dsi_get_phy(struct msm_dsi *msm_dsi)
>   	if (phy_pdev)
>   		msm_dsi->phy = platform_get_drvdata(phy_pdev);
>   
> +	*cphy_mode = of_property_read_bool(phy_node, "qcom,dsi-phy-cphy-mode");
>   	of_node_put(phy_node);
>   
>   	if (!phy_pdev || !msm_dsi->phy) {
> @@ -65,6 +66,7 @@ static void dsi_destroy(struct msm_dsi *msm_dsi)
>   static struct msm_dsi *dsi_init(struct platform_device *pdev)
>   {
>   	struct msm_dsi *msm_dsi;
> +	bool cphy_mode;
>   	int ret;
>   
>   	if (!pdev)
> @@ -79,13 +81,13 @@ static struct msm_dsi *dsi_init(struct platform_device *pdev)
>   	msm_dsi->pdev = pdev;
>   	platform_set_drvdata(pdev, msm_dsi);
>   
> -	/* Init dsi host */
> -	ret = msm_dsi_host_init(msm_dsi);
> +	/* GET dsi PHY */
> +	ret = dsi_get_phy(msm_dsi, &cphy_mode);
>   	if (ret)
>   		goto destroy_dsi;
>   
> -	/* GET dsi PHY */
> -	ret = dsi_get_phy(msm_dsi);
> +	/* Init dsi host */
> +	ret = msm_dsi_host_init(msm_dsi, cphy_mode);
>   	if (ret)
>   		goto destroy_dsi;


--
With best wishes
Dmitry