The DP PHYs on X1E80100 need the ref clock which is provided by the
TCSR CC.

The current X Elite devices supported upstream work fine without this
clock, because the boot firmware leaves this clock enabled. But we should
not rely on that. Also, even though this change breaks the ABI, it is
needed in order to make the driver disables this clock along with the
other ones, for a proper bring-down of the entire PHY.

So lets attach it to each of the DP PHYs in order to do that.

Cc: stable@vger.kernel.org # v6.9
Fixes: 1940c25eaa63 ("arm64: dts: qcom: x1e80100: Add display nodes")
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
---
 arch/arm64/boot/dts/qcom/hamoa.dtsi | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/hamoa.dtsi b/arch/arm64/boot/dts/qcom/hamoa.dtsi
index a17900eacb20396a9792efcfcd6ce6dd877435d1..59603616a3c229c69467c41e6043c63daa62b46b 100644
--- a/arch/arm64/boot/dts/qcom/hamoa.dtsi
+++ b/arch/arm64/boot/dts/qcom/hamoa.dtsi
@@ -5896,9 +5896,11 @@ mdss_dp2_phy: phy@aec2a00 {
 			      <0 0x0aec2000 0 0x1c8>;
 
 			clocks = <&dispcc DISP_CC_MDSS_DPTX2_AUX_CLK>,
-				 <&dispcc DISP_CC_MDSS_AHB_CLK>;
+				 <&dispcc DISP_CC_MDSS_AHB_CLK>,
+				 <&tcsr TCSR_EDP_CLKREF_EN>;
 			clock-names = "aux",
-				      "cfg_ahb";
+				      "cfg_ahb",
+				      "ref";
 
 			power-domains = <&rpmhpd RPMHPD_MX>;
 
@@ -5916,9 +5918,11 @@ mdss_dp3_phy: phy@aec5a00 {
 			      <0 0x0aec5000 0 0x1c8>;
 
 			clocks = <&dispcc DISP_CC_MDSS_DPTX3_AUX_CLK>,
-				 <&dispcc DISP_CC_MDSS_AHB_CLK>;
+				 <&dispcc DISP_CC_MDSS_AHB_CLK>,
+				 <&tcsr TCSR_EDP_CLKREF_EN>;
 			clock-names = "aux",
-				      "cfg_ahb";
+				      "cfg_ahb",
+				      "ref";
 
 			power-domains = <&rpmhpd RPMHPD_MX>;
 

-- 
2.48.1

On Wed, Oct 29, 2025 at 03:31:32PM +0200, Abel Vesa wrote:
> The DP PHYs on X1E80100 need the ref clock which is provided by the
> TCSR CC.
> 
> The current X Elite devices supported upstream work fine without this
> clock, because the boot firmware leaves this clock enabled. But we should
> not rely on that. Also, even though this change breaks the ABI, it is
> needed in order to make the driver disables this clock along with the
> other ones, for a proper bring-down of the entire PHY.
> 
> So lets attach it to each of the DP PHYs in order to do that.
> 
> Cc: stable@vger.kernel.org # v6.9
> Fixes: 1940c25eaa63 ("arm64: dts: qcom: x1e80100: Add display nodes")

Reviewed-by: Bjorn Andersson <andersson@kernel.org>

> Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
> ---
>  arch/arm64/boot/dts/qcom/hamoa.dtsi | 12 ++++++++----
>  1 file changed, 8 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/qcom/hamoa.dtsi b/arch/arm64/boot/dts/qcom/hamoa.dtsi
> index a17900eacb20396a9792efcfcd6ce6dd877435d1..59603616a3c229c69467c41e6043c63daa62b46b 100644
> --- a/arch/arm64/boot/dts/qcom/hamoa.dtsi
> +++ b/arch/arm64/boot/dts/qcom/hamoa.dtsi
> @@ -5896,9 +5896,11 @@ mdss_dp2_phy: phy@aec2a00 {
>  			      <0 0x0aec2000 0 0x1c8>;
>  
>  			clocks = <&dispcc DISP_CC_MDSS_DPTX2_AUX_CLK>,
> -				 <&dispcc DISP_CC_MDSS_AHB_CLK>;
> +				 <&dispcc DISP_CC_MDSS_AHB_CLK>,
> +				 <&tcsr TCSR_EDP_CLKREF_EN>;
>  			clock-names = "aux",
> -				      "cfg_ahb";
> +				      "cfg_ahb",
> +				      "ref";
>  
>  			power-domains = <&rpmhpd RPMHPD_MX>;
>  
> @@ -5916,9 +5918,11 @@ mdss_dp3_phy: phy@aec5a00 {
>  			      <0 0x0aec5000 0 0x1c8>;
>  
>  			clocks = <&dispcc DISP_CC_MDSS_DPTX3_AUX_CLK>,
> -				 <&dispcc DISP_CC_MDSS_AHB_CLK>;
> +				 <&dispcc DISP_CC_MDSS_AHB_CLK>,
> +				 <&tcsr TCSR_EDP_CLKREF_EN>;
>  			clock-names = "aux",
> -				      "cfg_ahb";
> +				      "cfg_ahb",
> +				      "ref";
>  
>  			power-domains = <&rpmhpd RPMHPD_MX>;
>  
> 
> -- 
> 2.48.1
>