[PATCH RFC v2] drm/msm/dpu: Configure DP INTF/PHY selector

Abhinav Kumar quic_abhinavk at quicinc.com
Tue Jun 25 01:39:08 UTC 2024



On 6/13/2024 4:17 AM, Dmitry Baryshkov wrote:
> From: Bjorn Andersson <andersson at kernel.org>
> 
> Some platforms provides a mechanism for configuring the mapping between
> (one or two) DisplayPort intfs and their PHYs.
> 
> In particular SC8180X provides this functionality, without a default
> configuration, resulting in no connection between its two external
> DisplayPort controllers and any PHYs.
> 

I have to cross-check internally about what makes it mandatory to 
program this only for sc8180xp. We were not programming this so far for 
any chipset and this register is present all the way from sm8150 till 
xe10100 and all the chipsets do not have a correct default value which 
makes me think whether this is required to be programmed.

Will update this thread once I do.

> The change implements the logic for optionally configuring which PHY
> each of the DP INTFs should be connected to and marks the SC8180X DPU to
> program 2 entries.
> 
> For now the request is simply to program the mapping 1:1, any support
> for alternative mappings is left until the use case arrise.
> 
> Note that e.g. msm-4.14 unconditionally maps INTF 0 to PHY 0 on all
> rlatforms, so perhaps this is needed in order to get DisplayPort working
> on some other platforms as well.
> 
> Signed-off-by: Bjorn Andersson <andersson at kernel.org>
> Co-developed-by: Bjorn Andersson <andersson at kernel.org>
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
> ---
> Changes in v2:
> - Removed entry from the catalog.
> - Reworked the interface of dpu_hw_dp_phy_intf_sel(). Pass two entries
>    for the PHYs instead of three entries.
> - It seems the register isn't present on sdm845, enabled the callback
>    only for DPU >= 5.x
> - Added a comment regarding the data being platform-specific.
> - Link to v1: https://lore.kernel.org/r/20230612221047.1886709-1-quic_bjorande@quicinc.com
> ---
>   drivers/gpu/drm/msm/disp/dpu1/dpu_hw_top.c | 39 +++++++++++++++++++++++++++---
>   drivers/gpu/drm/msm/disp/dpu1/dpu_hw_top.h | 18 ++++++++++++--
>   drivers/gpu/drm/msm/disp/dpu1/dpu_hwio.h   |  7 ++++++
>   drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c    | 11 ++++++++-
>   4 files changed, 69 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_top.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_top.c
> index 05e48cf4ec1d..a11fdbefc8d2 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_top.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_top.c
> @@ -231,8 +231,38 @@ static void dpu_hw_intf_audio_select(struct dpu_hw_mdp *mdp)
>   	DPU_REG_WRITE(c, HDMI_DP_CORE_SELECT, 0x1);
>   }
>   
> +static void dpu_hw_dp_phy_intf_sel(struct dpu_hw_mdp *mdp,
> +				   enum dpu_dp_phy_sel phys[2])
> +{
> +	struct dpu_hw_blk_reg_map *c = &mdp->hw;
> +	unsigned int intf;
> +	u32 sel = 0;
> +
> +	sel |= FIELD_PREP(MDP_DP_PHY_INTF_SEL_INTF0, phys[0]);
> +	sel |= FIELD_PREP(MDP_DP_PHY_INTF_SEL_INTF1, phys[1]);
> +
> +	for (intf = 0; intf < 2; intf++) {

I wonder if ARRAY_SIZE(phys) is better here.

> +		switch (phys[intf]) {
> +		case DPU_DP_PHY_0:
> +			sel |= FIELD_PREP(MDP_DP_PHY_INTF_SEL_PHY0, intf + 1);
> +			break;
> +		case DPU_DP_PHY_1:
> +			sel |= FIELD_PREP(MDP_DP_PHY_INTF_SEL_PHY1, intf + 1);
> +			break;
> +		case DPU_DP_PHY_2:
> +			sel |= FIELD_PREP(MDP_DP_PHY_INTF_SEL_PHY2, intf + 1);
> +			break;
> +		default:
> +			/* ignore */
> +			break;
> +		}
> +	}
> +
> +	DPU_REG_WRITE(c, MDP_DP_PHY_INTF_SEL, sel);
> +}
> +
>   static void _setup_mdp_ops(struct dpu_hw_mdp_ops *ops,
> -		unsigned long cap)
> +		unsigned long cap, const struct dpu_mdss_version *mdss_rev)
>   {
>   	ops->setup_split_pipe = dpu_hw_setup_split_pipe;
>   	ops->setup_clk_force_ctrl = dpu_hw_setup_clk_force_ctrl;
> @@ -245,6 +275,9 @@ static void _setup_mdp_ops(struct dpu_hw_mdp_ops *ops,
>   
>   	ops->get_safe_status = dpu_hw_get_safe_status;
>   
> +	if (mdss_rev->core_major_ver >= 5)
> +		ops->dp_phy_intf_sel = dpu_hw_dp_phy_intf_sel;
> +
>   	if (cap & BIT(DPU_MDP_AUDIO_SELECT))
>   		ops->intf_audio_select = dpu_hw_intf_audio_select;
>   }
> @@ -252,7 +285,7 @@ static void _setup_mdp_ops(struct dpu_hw_mdp_ops *ops,
>   struct dpu_hw_mdp *dpu_hw_mdptop_init(struct drm_device *dev,
>   				      const struct dpu_mdp_cfg *cfg,
>   				      void __iomem *addr,
> -				      const struct dpu_mdss_cfg *m)
> +				      const struct dpu_mdss_version *mdss_rev)
>   {
>   	struct dpu_hw_mdp *mdp;
>   
> @@ -270,7 +303,7 @@ struct dpu_hw_mdp *dpu_hw_mdptop_init(struct drm_device *dev,
>   	 * Assign ops
>   	 */
>   	mdp->caps = cfg;
> -	_setup_mdp_ops(&mdp->ops, mdp->caps->features);
> +	_setup_mdp_ops(&mdp->ops, mdp->caps->features, mdss_rev);
>   
>   	return mdp;
>   }
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_top.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_top.h
> index 6f3dc98087df..3a17e63b851c 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_top.h
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_top.h
> @@ -67,6 +67,13 @@ struct dpu_vsync_source_cfg {
>   	u32 vsync_source;
>   };
>   
> +enum dpu_dp_phy_sel {
> +	DPU_DP_PHY_NONE,
> +	DPU_DP_PHY_0,
> +	DPU_DP_PHY_1,
> +	DPU_DP_PHY_2,
> +};
> +
>   /**
>    * struct dpu_hw_mdp_ops - interface to the MDP TOP Hw driver functions
>    * Assumption is these functions will be called after clocks are enabled.
> @@ -125,6 +132,13 @@ struct dpu_hw_mdp_ops {
>   	void (*get_safe_status)(struct dpu_hw_mdp *mdp,
>   			struct dpu_danger_safe_status *status);
>   
> +	/**
> +	 * dp_phy_intf_sel - configure intf to phy mapping
> +	 * @mdp: mdp top context driver
> +	 * @phys: list of phys the DP interfaces should be connected to. 0 disables the INTF.
> +	 */
> +	void (*dp_phy_intf_sel)(struct dpu_hw_mdp *mdp, enum dpu_dp_phy_sel phys[2]);
> +
>   	/**
>   	 * intf_audio_select - select the external interface for audio
>   	 * @mdp: mdp top context driver
> @@ -148,12 +162,12 @@ struct dpu_hw_mdp {
>    * @dev:  Corresponding device for devres management
>    * @cfg:  MDP TOP configuration from catalog
>    * @addr: Mapped register io address of MDP
> - * @m:    Pointer to mdss catalog data
> + * @mdss_rev: dpu core's major and minor versions
>    */
>   struct dpu_hw_mdp *dpu_hw_mdptop_init(struct drm_device *dev,
>   				      const struct dpu_mdp_cfg *cfg,
>   				      void __iomem *addr,
> -				      const struct dpu_mdss_cfg *m);
> +				      const struct dpu_mdss_version *mdss_rev);
>   
>   void dpu_hw_mdp_destroy(struct dpu_hw_mdp *mdp);
>   
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hwio.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_hwio.h
> index 5acd5683d25a..f1acc04089af 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hwio.h
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hwio.h
> @@ -60,6 +60,13 @@
>   #define MDP_WD_TIMER_4_LOAD_VALUE       0x448
>   #define DCE_SEL                         0x450
>   
> +#define MDP_DP_PHY_INTF_SEL             0x460
> +#define MDP_DP_PHY_INTF_SEL_INTF0		GENMASK(3, 0)
> +#define MDP_DP_PHY_INTF_SEL_INTF1		GENMASK(6, 3)
> +#define MDP_DP_PHY_INTF_SEL_PHY0		GENMASK(9, 6)
> +#define MDP_DP_PHY_INTF_SEL_PHY1		GENMASK(12, 9)
> +#define MDP_DP_PHY_INTF_SEL_PHY2		GENMASK(15, 12)

These masks do not match the docs, the below ones are what I see:

#define MDP_DP_PHY_INTF_SEL_INTF0		GENMASK(2, 0)
#define MDP_DP_PHY_INTF_SEL_INTF1		GENMASK(5, 3)
#define MDP_DP_PHY_INTF_SEL_PHY0		GENMASK(8, 6)
#define MDP_DP_PHY_INTF_SEL_PHY1		GENMASK(11, 9)
#define MDP_DP_PHY_INTF_SEL_PHY2		GENMASK(14, 12)

> +
>   #define MDP_PERIPH_TOP0			MDP_WD_TIMER_0_CTL
>   #define MDP_PERIPH_TOP0_END		CLK_CTRL3
>   
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> index 1955848b1b78..9db5a784c92f 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> @@ -1102,7 +1102,7 @@ static int dpu_kms_hw_init(struct msm_kms *kms)
>   	dpu_kms->hw_mdp = dpu_hw_mdptop_init(dev,
>   					     dpu_kms->catalog->mdp,
>   					     dpu_kms->mmio,
> -					     dpu_kms->catalog);
> +					     dpu_kms->catalog->mdss_ver);
>   	if (IS_ERR(dpu_kms->hw_mdp)) {
>   		rc = PTR_ERR(dpu_kms->hw_mdp);
>   		DPU_ERROR("failed to get hw_mdp: %d\n", rc);
> @@ -1137,6 +1137,15 @@ static int dpu_kms_hw_init(struct msm_kms *kms)
>   		goto err_pm_put;
>   	}
>   
> +	/*
> +	 * We need to program DP <-> PHY relationship only for SC8180X.  If any
> +	 * other platform requires the same kind of programming, or if the INTF
> +	 * <->DP relationship isn't static anymore, this needs to be configured
> +	 * through the DT.
> +	 */
> +	if (of_device_is_compatible(dpu_kms->pdev->dev.of_node, "qcom,sc8180x-dpu"))
> +		dpu_kms->hw_mdp->ops.dp_phy_intf_sel(dpu_kms->hw_mdp, (unsigned int[]){ 1, 2, });
> +
>   	dpu_kms->hw_intr = dpu_hw_intr_init(dev, dpu_kms->mmio, dpu_kms->catalog);
>   	if (IS_ERR(dpu_kms->hw_intr)) {
>   		rc = PTR_ERR(dpu_kms->hw_intr);
> 
> ---
> base-commit: 03d44168cbd7fc57d5de56a3730427db758fc7f6
> change-id: 20240613-dp-phy-sel-1b06dc48ed73
> 
> Best regards,


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