Re: [PATCH] arm64: dts: renesas: sparrow-hawk: Reserve first 128 MiB of DRAM

From: Marek Vasut

Date: Wed Mar 25 2026 - 10:06:49 EST


On 3/25/26 2:08 PM, Geert Uytterhoeven wrote:

Hello Geert,

--- a/arch/arm64/boot/dts/renesas/r8a779g3-sparrow-hawk.dts
+++ b/arch/arm64/boot/dts/renesas/r8a779g3-sparrow-hawk.dts
@@ -118,6 +118,17 @@ memory@600000000 {
reg = <0x6 0x00000000 0x1 0x00000000>;
};

+ reserved-memory {
+ #address-cells = <2>;
+ #size-cells = <2>;
+ ranges;
+
+ tfa@40000000 {
+ reg = <0x0 0x40000000 0x0 0x8000000>;
+ no-map;
+ };
+ };

Obviously I don't like this very much, but I agree there is not much
else we can do at this point. Shall I add a

/* Temporary workaround for broken TFA BL31 */

comment while applying?

For maximum backward compatibility even with old TFA BL31 versions, which the users may run for whatever reason, I believe this reserved memory area is here to stay and won't be "Temporary".

But I will be looking into TFA to fill in this reserved-memory node properly for this and future SoCs.

Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
i.e. will queue in renesas-fixes for v7.0.
Thank you