[PATCH] arm64: dts: qcom: sc8280xp-huawei-gaokun3: Add dsi panel DT node

[PATCH] arm64: dts: qcom: sc8280xp-huawei-gaokun3: Add dsi panel DT node

[Pengyu Luo]

DSI panel driver have been added for a while, so add the DT node to
enable it. vdd{a,s}-supply for dsi, dsi_phy are blank since the DSDT
describes the wrong, no impact after manual disabling these wrong
supplies.

Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
---
 .../boot/dts/qcom/sc8280xp-huawei-gaokun3.dts | 165 ++++++++++++++++++
 1 file changed, 165 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/sc8280xp-huawei-gaokun3.dts b/arch/arm64/boot/dts/qcom/sc8280xp-huawei-gaokun3.dts
index f3c00be67081..658bb253394a 100644
--- a/arch/arm64/boot/dts/qcom/sc8280xp-huawei-gaokun3.dts
+++ b/arch/arm64/boot/dts/qcom/sc8280xp-huawei-gaokun3.dts
@@ -11,6 +11,7 @@
 
 /dts-v1/;
 
+#include <dt-bindings/clock/qcom,dsi-phy-28nm.h>
 #include <dt-bindings/iio/qcom,spmi-adc7-pm8350.h>
 #include <dt-bindings/gpio/gpio.h>
 #include <dt-bindings/input/gpio-keys.h>
@@ -98,6 +99,52 @@ switch-mode {
 		};
 	};
 
+	vreg_avdd_5p5: regulator-avdd-5p5 {
+		compatible = "regulator-fixed";
+
+		regulator-name = "vreg_avdd_5p5";
+		regulator-min-microvolt = <5500000>;
+		regulator-max-microvolt = <5500000>;
+
+		gpio = <&tlmm 53 GPIO_ACTIVE_HIGH>;
+		enable-active-high;
+
+		pinctrl-0 = <&avdd_reg_en>;
+		pinctrl-names = "default";
+
+		regulator-boot-on;
+	};
+
+	vreg_avee_5p5: regulator-avee-5p5 {
+		compatible = "regulator-fixed";
+
+		regulator-name = "vreg_avee_5p5";
+		regulator-min-microvolt = <5500000>;
+		regulator-max-microvolt = <5500000>;
+
+		gpio = <&tlmm 52 GPIO_ACTIVE_HIGH>;
+		enable-active-high;
+
+		pinctrl-0 = <&avee_reg_en>;
+		pinctrl-names = "default";
+
+		regulator-boot-on;
+	};
+
+	vreg_vddi_1p8: regulator-vddi-1p8 {
+		compatible = "regulator-fixed";
+
+		regulator-name = "vreg_vddi_1p8";
+
+		gpio = <&tlmm 0 GPIO_ACTIVE_HIGH>;
+		enable-active-high;
+
+		pinctrl-0 = <&vddi_reg_en>;
+		pinctrl-names = "default";
+
+		regulator-boot-on;
+	};
+
 	vreg_misc_3p3: regulator-misc-3p3 {
 		compatible = "regulator-fixed";
 
@@ -616,6 +663,9 @@ touchscreen@4f {
 		hid-descr-addr = <0x1>;
 		interrupts-extended = <&tlmm 175 IRQ_TYPE_LEVEL_LOW>;
 
+		/* TODO: set post-reset-deassert-delay-ms */
+		panel = <&panel>;
+
 		vdd-supply = <&vreg_misc_3p3>;
 		vddl-supply = <&vreg_s10b>;
 
@@ -738,6 +788,86 @@ &mdss0_dp1_out {
 	remote-endpoint = <&usb_1_qmpphy_dp_in>;
 };
 
+&mdss0_dsi0 {
+	/* real vdda is unknown */
+
+	qcom,dual-dsi-mode;
+	qcom,master-dsi;
+	qcom,sync-dual-dsi;
+
+	status = "okay";
+
+	panel: panel@0 {
+		compatible = "csot,ppc357db1-4", "himax,hx83121a";
+		reg = <0>;
+
+		pinctrl-0 = <&disp_reset_n>, <&mdp_vsync_default>;
+		pinctrl-names = "default";
+
+		reset-gpios = <&tlmm 38 GPIO_ACTIVE_LOW>;
+
+		vddi-supply = <&vreg_vddi_1p8>;
+		avdd-supply = <&vreg_avdd_5p5>;
+		avee-supply = <&vreg_avee_5p5>;
+
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port@0 {
+				reg = <0>;
+
+				panel_in_0: endpoint {
+					remote-endpoint = <&mdss0_dsi0_out>;
+				};
+			};
+
+			port@1 {
+				reg = <1>;
+
+				panel_in_1: endpoint {
+					remote-endpoint = <&mdss0_dsi1_out>;
+				};
+			};
+		};
+	};
+};
+
+&mdss0_dsi0_out {
+	data-lanes = <0 1 2 3>;
+	remote-endpoint = <&panel_in_0>;
+};
+
+&mdss0_dsi0_phy {
+	/* real vdds is unknown */
+
+	status = "okay";
+};
+
+&mdss0_dsi1 {
+	/* real vdda is unknown */
+
+	qcom,dual-dsi-mode;
+	qcom,sync-dual-dsi;
+
+	status = "okay";
+
+	/* DSI1 is slave, so use DSI0 clocks */
+	assigned-clock-parents = <&mdss0_dsi0_phy DSI_BYTE_PLL_CLK>,
+				 <&mdss0_dsi0_phy DSI_PIXEL_PLL_CLK>;
+};
+
+&mdss0_dsi1_out {
+	data-lanes = <0 1 2 3>;
+	remote-endpoint = <&panel_in_1>;
+};
+
+&mdss0_dsi1_phy {
+	/* real vdds is unknown */
+
+	status = "okay";
+};
+
 &pcie2a {
 	perst-gpios = <&tlmm 143 GPIO_ACTIVE_LOW>;
 	wake-gpios = <&tlmm 145 GPIO_ACTIVE_LOW>;
@@ -1303,6 +1433,20 @@ &tlmm {
 
 	gpio-reserved-ranges = <70 2>, <74 6>, <83 4>, <125 2>, <128 2>, <154 4>;
 
+	avdd_reg_en: avdd-reg-en-state {
+		pins = "gpio53";
+		function = "gpio";
+		drive-strength = <2>;
+		bias-disable;
+	};
+
+	avee_reg_en: avee-reg-en-state {
+		pins = "gpio52";
+		function = "gpio";
+		drive-strength = <2>;
+		bias-disable;
+	};
+
 	bt_default: bt-default-state {
 		hstp-bt-en-pins {
 			pins = "gpio133";
@@ -1318,6 +1462,20 @@ hstp-sw-ctrl-pins {
 		};
 	};
 
+	disp_reset_n: disp-reset-n-state {
+		pins = "gpio38";
+		function = "gpio";
+		drive-strength = <2>;
+		bias-pull-up;
+	};
+
+	mdp_vsync_default: mdp-vsync-default-state {
+		pins = "gpio8";
+		function = "mdp_vsync";
+		drive-strength = <2>;
+		bias-disable;
+	};
+
 	i2c4_default: i2c4-default-state {
 		pins = "gpio171", "gpio172";
 		function = "qup4";
@@ -1470,6 +1628,13 @@ usb1_sbu_default: usb1-sbu-state {
 		bias-disable;
 	};
 
+	vddi_reg_en: vddi-reg-en-state {
+		pins = "gpio0";
+		function = "gpio";
+		drive-strength = <2>;
+		bias-disable;
+	};
+
 	wcd_default: wcd-default-state {
 		reset-pins {
 			pins = "gpio106";
-- 
2.54.0

Re: [PATCH] arm64: dts: qcom: sc8280xp-huawei-gaokun3: Add dsi panel DT node

[Konrad Dybcio]

On 6/30/26 6:22 AM, Pengyu Luo wrote:
> DSI panel driver have been added for a while, so add the DT node to
> enable it. vdd{a,s}-supply for dsi, dsi_phy are blank since the DSDT
> describes the wrong, no impact after manual disabling these wrong
> supplies.
> 
> Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
> ---

[...]

> +&mdss0_dsi0 {
> +	/* real vdda is unknown */
> +

L3B: DSI core 1.2 V (both?)
L6B: DSI0/1 PLL and core 0.9 V

Konrad

Re: [PATCH] arm64: dts: qcom: sc8280xp-huawei-gaokun3: Add dsi panel DT node

[Konrad Dybcio]

On 6/30/26 6:22 AM, Pengyu Luo wrote:
> DSI panel driver have been added for a while, so add the DT node to
> enable it. vdd{a,s}-supply for dsi, dsi_phy are blank since the DSDT
> describes the wrong, no impact after manual disabling these wrong
> supplies.
> 
> Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
> ---

[...]


> @@ -616,6 +663,9 @@ touchscreen@4f {
>  		hid-descr-addr = <0x1>;
>  		interrupts-extended = <&tlmm 175 IRQ_TYPE_LEVEL_LOW>;
>  
> +		/* TODO: set post-reset-deassert-delay-ms */
> +		panel = <&panel>;

So.. are you going to add it?

Konrad

Re: [PATCH] arm64: dts: qcom: sc8280xp-huawei-gaokun3: Add dsi panel DT node

[Pengyu Luo]

On Tue, Jun 30, 2026 at 5:18 PM Konrad Dybcio
<konrad.dybcio@oss.qualcomm.com> wrote:
>
> On 6/30/26 6:22 AM, Pengyu Luo wrote:
> > DSI panel driver have been added for a while, so add the DT node to
> > enable it. vdd{a,s}-supply for dsi, dsi_phy are blank since the DSDT
> > describes the wrong, no impact after manual disabling these wrong
> > supplies.
> >
> > Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
> > ---
>
> [...]
>
> > +&mdss0_dsi0 {
> > +     /* real vdda is unknown */
> > +
>
> L3B: DSI core 1.2 V (both?)
> L6B: DSI0/1 PLL and core 0.9 V
>

Yes, that is what I saw in the DSDT, however, I can disable them
safely (hack the regulator driver to add a sysfs to handle these
regulators), the panel works well.

Best wishes,
Pengyu

> Konrad

Re: [PATCH] arm64: dts: qcom: sc8280xp-huawei-gaokun3: Add dsi panel DT node

[Pengyu Luo]

On Tue, Jun 30, 2026 at 5:18 PM Konrad Dybcio
<konrad.dybcio@oss.qualcomm.com> wrote:
>
> On 6/30/26 6:22 AM, Pengyu Luo wrote:
> > DSI panel driver have been added for a while, so add the DT node to
> > enable it. vdd{a,s}-supply for dsi, dsi_phy are blank since the DSDT
> > describes the wrong, no impact after manual disabling these wrong
> > supplies.
> >
> > Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
> > ---
>
> [...]
>
>
> > @@ -616,6 +663,9 @@ touchscreen@4f {
> >               hid-descr-addr = <0x1>;
> >               interrupts-extended = <&tlmm 175 IRQ_TYPE_LEVEL_LOW>;
> >
> > +             /* TODO: set post-reset-deassert-delay-ms */
> > +             panel = <&panel>;
>
> So.. are you going to add it?
>

Yes, this is a TDDI, so the timing(ts after display) is required,
panel_follower will handle this.

Best wishes,
Pengyu

> Konrad

Re: [PATCH] arm64: dts: qcom: sc8280xp-huawei-gaokun3: Add dsi panel DT node

[Konrad Dybcio]

On 6/30/26 11:28 AM, Pengyu Luo wrote:
> On Tue, Jun 30, 2026 at 5:18 PM Konrad Dybcio
> <konrad.dybcio@oss.qualcomm.com> wrote:
>>
>> On 6/30/26 6:22 AM, Pengyu Luo wrote:
>>> DSI panel driver have been added for a while, so add the DT node to
>>> enable it. vdd{a,s}-supply for dsi, dsi_phy are blank since the DSDT
>>> describes the wrong, no impact after manual disabling these wrong
>>> supplies.
>>>
>>> Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
>>> ---
>>
>> [...]
>>
>>> +&mdss0_dsi0 {
>>> +     /* real vdda is unknown */
>>> +
>>
>> L3B: DSI core 1.2 V (both?)
>> L6B: DSI0/1 PLL and core 0.9 V
>>
> 
> Yes, that is what I saw in the DSDT, however, I can disable them
> safely (hack the regulator driver to add a sysfs to handle these
> regulators), the panel works well.

L3B additionally powers CSIPHY2/3, EDP0/1, REFGEN (probably why it
ends up being on), UFSPHY and USB1_PHY

L6B additionally powers the same components, minus refgen and USB

Konrad

Re: [PATCH] arm64: dts: qcom: sc8280xp-huawei-gaokun3: Add dsi panel DT node

[Pengyu Luo]

On Tue, Jun 30, 2026 at 6:29 PM Konrad Dybcio
<konrad.dybcio@oss.qualcomm.com> wrote:
>
> On 6/30/26 11:28 AM, Pengyu Luo wrote:
> > On Tue, Jun 30, 2026 at 5:18 PM Konrad Dybcio
> > <konrad.dybcio@oss.qualcomm.com> wrote:
> >>
> >> On 6/30/26 6:22 AM, Pengyu Luo wrote:
> >>> DSI panel driver have been added for a while, so add the DT node to
> >>> enable it. vdd{a,s}-supply for dsi, dsi_phy are blank since the DSDT
> >>> describes the wrong, no impact after manual disabling these wrong
> >>> supplies.
> >>>
> >>> Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
> >>> ---
> >>
> >> [...]
> >>
> >>> +&mdss0_dsi0 {
> >>> +     /* real vdda is unknown */
> >>> +
> >>
> >> L3B: DSI core 1.2 V (both?)
> >> L6B: DSI0/1 PLL and core 0.9 V
> >>
> >
> > Yes, that is what I saw in the DSDT, however, I can disable them
> > safely (hack the regulator driver to add a sysfs to handle these
> > regulators), the panel works well.
>
> L3B additionally powers CSIPHY2/3, EDP0/1, REFGEN (probably why it
> ends up being on), UFSPHY and USB1_PHY
>
> L6B additionally powers the same components, minus refgen and USB
>

No, I confirmed they are totally disabled, since there is a way to check it now.
https://lore.kernel.org/linux-arm-msm/20260420-read-rpmh-v3-v4-0-70c152e6c958@oss.qualcomm.com/

Best wishes,
Pengyu

> Konrad

Re: [PATCH] arm64: dts: qcom: sc8280xp-huawei-gaokun3: Add dsi panel DT node

[Konrad Dybcio]

On 6/30/26 12:30 PM, Pengyu Luo wrote:
> On Tue, Jun 30, 2026 at 6:29 PM Konrad Dybcio
> <konrad.dybcio@oss.qualcomm.com> wrote:
>>
>> On 6/30/26 11:28 AM, Pengyu Luo wrote:
>>> On Tue, Jun 30, 2026 at 5:18 PM Konrad Dybcio
>>> <konrad.dybcio@oss.qualcomm.com> wrote:
>>>>
>>>> On 6/30/26 6:22 AM, Pengyu Luo wrote:
>>>>> DSI panel driver have been added for a while, so add the DT node to
>>>>> enable it. vdd{a,s}-supply for dsi, dsi_phy are blank since the DSDT
>>>>> describes the wrong, no impact after manual disabling these wrong
>>>>> supplies.
>>>>>
>>>>> Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
>>>>> ---
>>>>
>>>> [...]
>>>>
>>>>> +&mdss0_dsi0 {
>>>>> +     /* real vdda is unknown */
>>>>> +
>>>>
>>>> L3B: DSI core 1.2 V (both?)
>>>> L6B: DSI0/1 PLL and core 0.9 V
>>>>
>>>
>>> Yes, that is what I saw in the DSDT, however, I can disable them
>>> safely (hack the regulator driver to add a sysfs to handle these
>>> regulators), the panel works well.
>>
>> L3B additionally powers CSIPHY2/3, EDP0/1, REFGEN (probably why it
>> ends up being on), UFSPHY and USB1_PHY
>>
>> L6B additionally powers the same components, minus refgen and USB
>>
> 
> No, I confirmed they are totally disabled, since there is a way to check it now.
> https://lore.kernel.org/linux-arm-msm/20260420-read-rpmh-v3-v4-0-70c152e6c958@oss.qualcomm.com/

This presents you with the status of the votes casted by HLOS, not
the actual hardware state

To get the latter, you'd have to dump the SPMI registers

Konrad

Re: [PATCH] arm64: dts: qcom: sc8280xp-huawei-gaokun3: Add dsi panel DT node

[Pengyu Luo]

On Tue, Jun 30, 2026 at 6:34 PM Konrad Dybcio
<konrad.dybcio@oss.qualcomm.com> wrote:
>
> On 6/30/26 12:30 PM, Pengyu Luo wrote:
> > On Tue, Jun 30, 2026 at 6:29 PM Konrad Dybcio
> > <konrad.dybcio@oss.qualcomm.com> wrote:
> >>
> >> On 6/30/26 11:28 AM, Pengyu Luo wrote:
> >>> On Tue, Jun 30, 2026 at 5:18 PM Konrad Dybcio
> >>> <konrad.dybcio@oss.qualcomm.com> wrote:
> >>>>
> >>>> On 6/30/26 6:22 AM, Pengyu Luo wrote:
> >>>>> DSI panel driver have been added for a while, so add the DT node to
> >>>>> enable it. vdd{a,s}-supply for dsi, dsi_phy are blank since the DSDT
> >>>>> describes the wrong, no impact after manual disabling these wrong
> >>>>> supplies.
> >>>>>
> >>>>> Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
> >>>>> ---
> >>>>
> >>>> [...]
> >>>>
> >>>>> +&mdss0_dsi0 {
> >>>>> +     /* real vdda is unknown */
> >>>>> +
> >>>>
> >>>> L3B: DSI core 1.2 V (both?)
> >>>> L6B: DSI0/1 PLL and core 0.9 V
> >>>>
> >>>
> >>> Yes, that is what I saw in the DSDT, however, I can disable them
> >>> safely (hack the regulator driver to add a sysfs to handle these
> >>> regulators), the panel works well.
> >>
> >> L3B additionally powers CSIPHY2/3, EDP0/1, REFGEN (probably why it
> >> ends up being on), UFSPHY and USB1_PHY
> >>
> >> L6B additionally powers the same components, minus refgen and USB
> >>
> >
> > No, I confirmed they are totally disabled, since there is a way to check it now.
> > https://lore.kernel.org/linux-arm-msm/20260420-read-rpmh-v3-v4-0-70c152e6c958@oss.qualcomm.com/
>
> This presents you with the status of the votes casted by HLOS, not
> the actual hardware state
>

If so, non-HLOS will vote on some critical regulators to keep them on,
IIRC, once I disabled L9D, system reseted immediately.

> To get the latter, you'd have to dump the SPMI registers
>
I will appreciate it if you provide more information.

Best wishes,
Pengyu

> Konrad

Re: [PATCH] arm64: dts: qcom: sc8280xp-huawei-gaokun3: Add dsi panel DT node

[Konrad Dybcio]

On 6/30/26 12:41 PM, Pengyu Luo wrote:
> On Tue, Jun 30, 2026 at 6:34 PM Konrad Dybcio
> <konrad.dybcio@oss.qualcomm.com> wrote:
>>
>> On 6/30/26 12:30 PM, Pengyu Luo wrote:
>>> On Tue, Jun 30, 2026 at 6:29 PM Konrad Dybcio
>>> <konrad.dybcio@oss.qualcomm.com> wrote:
>>>>
>>>> On 6/30/26 11:28 AM, Pengyu Luo wrote:
>>>>> On Tue, Jun 30, 2026 at 5:18 PM Konrad Dybcio
>>>>> <konrad.dybcio@oss.qualcomm.com> wrote:
>>>>>>
>>>>>> On 6/30/26 6:22 AM, Pengyu Luo wrote:
>>>>>>> DSI panel driver have been added for a while, so add the DT node to
>>>>>>> enable it. vdd{a,s}-supply for dsi, dsi_phy are blank since the DSDT
>>>>>>> describes the wrong, no impact after manual disabling these wrong
>>>>>>> supplies.
>>>>>>>
>>>>>>> Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
>>>>>>> ---
>>>>>>
>>>>>> [...]
>>>>>>
>>>>>>> +&mdss0_dsi0 {
>>>>>>> +     /* real vdda is unknown */
>>>>>>> +
>>>>>>
>>>>>> L3B: DSI core 1.2 V (both?)
>>>>>> L6B: DSI0/1 PLL and core 0.9 V
>>>>>>
>>>>>
>>>>> Yes, that is what I saw in the DSDT, however, I can disable them
>>>>> safely (hack the regulator driver to add a sysfs to handle these
>>>>> regulators), the panel works well.
>>>>
>>>> L3B additionally powers CSIPHY2/3, EDP0/1, REFGEN (probably why it
>>>> ends up being on), UFSPHY and USB1_PHY
>>>>
>>>> L6B additionally powers the same components, minus refgen and USB
>>>>
>>>
>>> No, I confirmed they are totally disabled, since there is a way to check it now.
>>> https://lore.kernel.org/linux-arm-msm/20260420-read-rpmh-v3-v4-0-70c152e6c958@oss.qualcomm.com/
>>
>> This presents you with the status of the votes casted by HLOS, not
>> the actual hardware state
>>
> 
> If so, non-HLOS will vote on some critical regulators to keep them on,
> IIRC, once I disabled L9D, system reseted immediately.

NHLOS will generally ensure that the hardware that it needs is
powered. This does not extend to hardware that *you* may want to
access in Linux (or which was left online by UEFI), which I suspect
was the case here

>> To get the latter, you'd have to dump the SPMI registers
>>
> I will appreciate it if you provide more information.

Take a look at drivers/regulator/qcom_spmi-regulator.c, you can get
the actual live value of the enable register and the voltage selector
for each regulator

Konrad

Re: [PATCH] arm64: dts: qcom: sc8280xp-huawei-gaokun3: Add dsi panel DT node

[Pengyu Luo]

On Wed, Jul 1, 2026 at 7:45 PM Konrad Dybcio
<konrad.dybcio@oss.qualcomm.com> wrote:
>
> On 6/30/26 12:41 PM, Pengyu Luo wrote:
> > On Tue, Jun 30, 2026 at 6:34 PM Konrad Dybcio
> > <konrad.dybcio@oss.qualcomm.com> wrote:
> >>
> >> On 6/30/26 12:30 PM, Pengyu Luo wrote:
> >>> On Tue, Jun 30, 2026 at 6:29 PM Konrad Dybcio
> >>> <konrad.dybcio@oss.qualcomm.com> wrote:
> >>>>
> >>>> On 6/30/26 11:28 AM, Pengyu Luo wrote:
> >>>>> On Tue, Jun 30, 2026 at 5:18 PM Konrad Dybcio
> >>>>> <konrad.dybcio@oss.qualcomm.com> wrote:
> >>>>>>
> >>>>>> On 6/30/26 6:22 AM, Pengyu Luo wrote:
> >>>>>>> DSI panel driver have been added for a while, so add the DT node to
> >>>>>>> enable it. vdd{a,s}-supply for dsi, dsi_phy are blank since the DSDT
> >>>>>>> describes the wrong, no impact after manual disabling these wrong
> >>>>>>> supplies.
> >>>>>>>
> >>>>>>> Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
> >>>>>>> ---
> >>>>>>
> >>>>>> [...]
> >>>>>>
> >>>>>>> +&mdss0_dsi0 {
> >>>>>>> +     /* real vdda is unknown */
> >>>>>>> +
> >>>>>>
> >>>>>> L3B: DSI core 1.2 V (both?)
> >>>>>> L6B: DSI0/1 PLL and core 0.9 V
> >>>>>>
> >>>>>
> >>>>> Yes, that is what I saw in the DSDT, however, I can disable them
> >>>>> safely (hack the regulator driver to add a sysfs to handle these
> >>>>> regulators), the panel works well.
> >>>>
> >>>> L3B additionally powers CSIPHY2/3, EDP0/1, REFGEN (probably why it
> >>>> ends up being on), UFSPHY and USB1_PHY
> >>>>
> >>>> L6B additionally powers the same components, minus refgen and USB
> >>>>
> >>>
> >>> No, I confirmed they are totally disabled, since there is a way to check it now.
> >>> https://lore.kernel.org/linux-arm-msm/20260420-read-rpmh-v3-v4-0-70c152e6c958@oss.qualcomm.com/
> >>
> >> This presents you with the status of the votes casted by HLOS, not
> >> the actual hardware state
> >>
> >
> > If so, non-HLOS will vote on some critical regulators to keep them on,
> > IIRC, once I disabled L9D, system reseted immediately.
>
> NHLOS will generally ensure that the hardware that it needs is
> powered. This does not extend to hardware that *you* may want to
> access in Linux (or which was left online by UEFI), which I suspect
> was the case here
>
> >> To get the latter, you'd have to dump the SPMI registers
> >>
> > I will appreciate it if you provide more information.
>
> Take a look at drivers/regulator/qcom_spmi-regulator.c, you can get
> the actual live value of the enable register and the voltage selector
> for each regulator
>

Thanks! I will look into this later.

Best wishes,
Pengyu

> Konrad

Re: [PATCH] arm64: dts: qcom: sc8280xp-huawei-gaokun3: Add dsi panel DT node

[Pengyu Luo]

On Wed, Jul 1, 2026 at 7:45 PM Konrad Dybcio
<konrad.dybcio@oss.qualcomm.com> wrote:
>
> On 6/30/26 12:41 PM, Pengyu Luo wrote:
> > On Tue, Jun 30, 2026 at 6:34 PM Konrad Dybcio
> > <konrad.dybcio@oss.qualcomm.com> wrote:
> >>
> >> On 6/30/26 12:30 PM, Pengyu Luo wrote:
> >>> On Tue, Jun 30, 2026 at 6:29 PM Konrad Dybcio
> >>> <konrad.dybcio@oss.qualcomm.com> wrote:
> >>>>
> >>>> On 6/30/26 11:28 AM, Pengyu Luo wrote:
> >>>>> On Tue, Jun 30, 2026 at 5:18 PM Konrad Dybcio
> >>>>> <konrad.dybcio@oss.qualcomm.com> wrote:
> >>>>>>
> >>>>>> On 6/30/26 6:22 AM, Pengyu Luo wrote:
> >>>>>>> DSI panel driver have been added for a while, so add the DT node to
> >>>>>>> enable it. vdd{a,s}-supply for dsi, dsi_phy are blank since the DSDT
> >>>>>>> describes the wrong, no impact after manual disabling these wrong
> >>>>>>> supplies.
> >>>>>>>
> >>>>>>> Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
> >>>>>>> ---
> >>>>>>
> >>>>>> [...]
> >>>>>>
> >>>>>>> +&mdss0_dsi0 {
> >>>>>>> +     /* real vdda is unknown */
> >>>>>>> +
> >>>>>>
> >>>>>> L3B: DSI core 1.2 V (both?)
> >>>>>> L6B: DSI0/1 PLL and core 0.9 V
> >>>>>>
> >>>>>
> >>>>> Yes, that is what I saw in the DSDT, however, I can disable them
> >>>>> safely (hack the regulator driver to add a sysfs to handle these
> >>>>> regulators), the panel works well.
> >>>>
> >>>> L3B additionally powers CSIPHY2/3, EDP0/1, REFGEN (probably why it
> >>>> ends up being on), UFSPHY and USB1_PHY
> >>>>
> >>>> L6B additionally powers the same components, minus refgen and USB
> >>>>
> >>>
> >>> No, I confirmed they are totally disabled, since there is a way to check it now.
> >>> https://lore.kernel.org/linux-arm-msm/20260420-read-rpmh-v3-v4-0-70c152e6c958@oss.qualcomm.com/
> >>
> >> This presents you with the status of the votes casted by HLOS, not
> >> the actual hardware state
> >>
> >
> > If so, non-HLOS will vote on some critical regulators to keep them on,
> > IIRC, once I disabled L9D, system reseted immediately.
>
> NHLOS will generally ensure that the hardware that it needs is
> powered. This does not extend to hardware that *you* may want to
> access in Linux (or which was left online by UEFI), which I suspect
> was the case here
>
> >> To get the latter, you'd have to dump the SPMI registers
> >>
> > I will appreciate it if you provide more information.
>
> Take a look at drivers/regulator/qcom_spmi-regulator.c, you can get
> the actual live value of the enable register and the voltage selector
> for each regulator
>

Hi, Konrad. The real case seems to be as you said. After disabling l3b
and l6b via rpmh,

# cat /sys/kernel/debug/regmap/0-01/registers | grep -E 'c[1-9a]46:'
c146: 80
c246: 00
c346: 80 # l3b en
c446: 80
c546: 00
c646: 80 # l6b en
c746: 00
c846: 80
c946: 00
ca46: 80

Could you please have a check if this node is available for
sc8280xp?(I want to write 0 to 0xc346 and 0x0646 to ensure the ldo
disabling will  turn off the display.) This is copied from sm8350, if
the fuse register is 0x7820a8 for sc8280xp as well, then it is fused
as disabled.

        spmi_debug_bus: qcom,spmi-debug@6b12000 {
                compatible = "qcom,spmi-pmic-arb-debug";
                reg = <0 0x06b12000 0 0x60>, <0 0x7820a8 0 0x4>;
                reg-names = "core", "fuse";
                clocks = <&aoss_qmp>;
                clock-names = "core_clk";
                qcom,fuse-disable-bit = <24>;
                #address-cells = <2>;
                #size-cells = <0>;
                status = "okay";
        }

Best wishes,
Pengyu


> Konrad