[PATCH v2] arm64: dts: qcom: sdm845-db845c: Mark cont splash memory region as reserved

[PATCH v2] arm64: dts: qcom: sdm845-db845c: Mark cont splash memory region as reserved

[Amit Pundir]

Adding a reserved memory region for the framebuffer memory
(the splash memory region set up by the bootloader).

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
---
v2: Updated commit message.

There was some dicussion on v1 but it didn't go anywhere,
https://lore.kernel.org/linux-kernel/20230124182857.1524912-1-amit.pundir@linaro.org/T/#u.
The general consensus is that this memory should be freed and be
made resuable but that (releasing this piece of memory) has been
tried before and it is not trivial to return the reserved memory
node to the system RAM pool in this case.

 arch/arm64/boot/dts/qcom/sdm845-db845c.dts | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/sdm845-db845c.dts b/arch/arm64/boot/dts/qcom/sdm845-db845c.dts
index e14fe9bbb386..10a06ee8e262 100644
--- a/arch/arm64/boot/dts/qcom/sdm845-db845c.dts
+++ b/arch/arm64/boot/dts/qcom/sdm845-db845c.dts
@@ -101,6 +101,14 @@ hdmi_con: endpoint {
 		};
 	};
 
+	reserved-memory {
+		/* Cont splash region set up by the bootloader */
+		cont_splash_mem: framebuffer@9d400000 {
+			reg = <0x0 0x9d400000 0x0 0x2400000>;
+			no-map;
+		};
+	};
+
 	lt9611_1v8: lt9611-vdd18-regulator {
 		compatible = "regulator-fixed";
 		regulator-name = "LT9611_1V8";
-- 
2.25.1

Re: [PATCH v2] arm64: dts: qcom: sdm845-db845c: Mark cont splash memory region as reserved

[Konrad Dybcio]

On 15.06.2023 16:27, Amit Pundir wrote:
> Adding a reserved memory region for the framebuffer memory
> (the splash memory region set up by the bootloader).
> 
> Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
> ---
> v2: Updated commit message.
> 
> There was some dicussion on v1 but it didn't go anywhere,
> https://lore.kernel.org/linux-kernel/20230124182857.1524912-1-amit.pundir@linaro.org/T/#u.
> The general consensus is that this memory should be freed and be
> made resuable but that (releasing this piece of memory) has been
> tried before and it is not trivial to return the reserved memory
> node to the system RAM pool in this case.
> 
>  arch/arm64/boot/dts/qcom/sdm845-db845c.dts | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sdm845-db845c.dts b/arch/arm64/boot/dts/qcom/sdm845-db845c.dts
> index e14fe9bbb386..10a06ee8e262 100644
> --- a/arch/arm64/boot/dts/qcom/sdm845-db845c.dts
> +++ b/arch/arm64/boot/dts/qcom/sdm845-db845c.dts
> @@ -101,6 +101,14 @@ hdmi_con: endpoint {
>  		};
>  	};
>  
> +	reserved-memory {
> +		/* Cont splash region set up by the bootloader */
> +		cont_splash_mem: framebuffer@9d400000 {
> +			reg = <0x0 0x9d400000 0x0 0x2400000>;
> +			no-map;
> +		};
> +	};
&mdss {
	memory-region = <&cont_splash_mem>;
};

?

Konrad
> +
>  	lt9611_1v8: lt9611-vdd18-regulator {
>  		compatible = "regulator-fixed";
>  		regulator-name = "LT9611_1V8";

Re: [PATCH v2] arm64: dts: qcom: sdm845-db845c: Mark cont splash memory region as reserved

[Amit Pundir]

On Thu, 15 Jun 2023 at 22:56, Konrad Dybcio <konrad.dybcio@linaro.org> wrote:
>
> On 15.06.2023 16:27, Amit Pundir wrote:
> > Adding a reserved memory region for the framebuffer memory
> > (the splash memory region set up by the bootloader).
> >
> > Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
> > ---
> > v2: Updated commit message.
> >
> > There was some dicussion on v1 but it didn't go anywhere,
> > https://lore.kernel.org/linux-kernel/20230124182857.1524912-1-amit.pundir@linaro.org/T/#u.
> > The general consensus is that this memory should be freed and be
> > made resuable but that (releasing this piece of memory) has been
> > tried before and it is not trivial to return the reserved memory
> > node to the system RAM pool in this case.
> >
> >  arch/arm64/boot/dts/qcom/sdm845-db845c.dts | 8 ++++++++
> >  1 file changed, 8 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/qcom/sdm845-db845c.dts b/arch/arm64/boot/dts/qcom/sdm845-db845c.dts
> > index e14fe9bbb386..10a06ee8e262 100644
> > --- a/arch/arm64/boot/dts/qcom/sdm845-db845c.dts
> > +++ b/arch/arm64/boot/dts/qcom/sdm845-db845c.dts
> > @@ -101,6 +101,14 @@ hdmi_con: endpoint {
> >               };
> >       };
> >
> > +     reserved-memory {
> > +             /* Cont splash region set up by the bootloader */
> > +             cont_splash_mem: framebuffer@9d400000 {
> > +                     reg = <0x0 0x9d400000 0x0 0x2400000>;
> > +                     no-map;
> > +             };
> > +     };
> &mdss {
>         memory-region = <&cont_splash_mem>;
> };
>
> ?

Thank you. Updated in v3.

>
> Konrad
> > +
> >       lt9611_1v8: lt9611-vdd18-regulator {
> >               compatible = "regulator-fixed";
> >               regulator-name = "LT9611_1V8";