[PATCH] arm64: dts: renesas: r8a77951: Add reserved memory region

From: Detlev Casanova
Date: Mon Nov 14 2022 - 14:49:48 EST


The 0x3000000 bytes memory region starting at 0x54000000 is
reserved for the lossy_decompression hardware that will try to
decompress any data written in the region.

Mark the region as no-map to prevent linux from using it as RAM.

Signed-off-by: Detlev Casanova <detlev.casanova@xxxxxxxxxxxxx>
---
arch/arm64/boot/dts/renesas/r8a77951.dtsi | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/arch/arm64/boot/dts/renesas/r8a77951.dtsi b/arch/arm64/boot/dts/renesas/r8a77951.dtsi
index 07c8763c1e77..171833d91313 100644
--- a/arch/arm64/boot/dts/renesas/r8a77951.dtsi
+++ b/arch/arm64/boot/dts/renesas/r8a77951.dtsi
@@ -290,6 +290,18 @@ CPU_SLEEP_1: cpu-sleep-1 {
};
};

+ reserved-memory {
+ #address-cells = <2>;
+ #size-cells = <2>;
+ ranges;
+
+ /* device specific region for Lossy Decompression */
+ lossy_decompress: memory-region@54000000 {
+ no-map;
+ reg = <0x00000000 0x54000000 0x0 0x03000000>;
+ };
+ };
+
extal_clk: extal {
compatible = "fixed-clock";
#clock-cells = <0>;
--
2.38.1