diff mbox series

[v3] arm64: dts: qcom: sdm845-db845c: Mark cont splash memory region as reserved

Message ID 20230616065123.3710734-1-amit.pundir@linaro.org (mailing list archive)
State Superseded
Headers show
Series [v3] arm64: dts: qcom: sdm845-db845c: Mark cont splash memory region as reserved | expand

Commit Message

Amit Pundir June 16, 2023, 6:51 a.m. UTC
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>
---
v3: Point this reserved region to MDSS.

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 | 9 +++++++++
 1 file changed, 9 insertions(+)

Comments

Krzysztof Kozlowski July 10, 2023, 2:48 p.m. UTC | #1
On 16/06/2023 08:51, 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>
> ---
> v3: Point this reserved region to MDSS.
> 
> 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 | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sdm845-db845c.dts b/arch/arm64/boot/dts/qcom/sdm845-db845c.dts
> index df2fde9063dc..503136eb9c06 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";
> @@ -517,6 +525,7 @@ &i2c14 {
>  };
>  
>  &mdss {
> +	memory-region = <&cont_splash_mem>;

Just to be sure: does this pass the dtbs_check testing? I would say it
does not and wasn't tested :(

Best regards,
Krzysztof
diff mbox series

Patch

diff --git a/arch/arm64/boot/dts/qcom/sdm845-db845c.dts b/arch/arm64/boot/dts/qcom/sdm845-db845c.dts
index df2fde9063dc..503136eb9c06 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";
@@ -517,6 +525,7 @@  &i2c14 {
 };
 
 &mdss {
+	memory-region = <&cont_splash_mem>;
 	status = "okay";
 };