diff --git a/arch/arm/boot/dts/ste-db8500.dtsi b/arch/arm/boot/dts/ste-db8500.dtsi
index d309fad32229d9adc3c88ff7c789d04aa7b6b3cd..344d29853bf76f1300872822fd4ba6d0297f903d 100644
--- a/arch/arm/boot/dts/ste-db8500.dtsi
+++ b/arch/arm/boot/dts/ste-db8500.dtsi
@@ -12,4 +12,42 @@
 					    200000 0>;
 		};
 	};
+
+	reserved-memory {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges;
+
+		/* Modem trace memory */
+		ram@06000000 {
+			reg = <0x06000000 0x00f00000>;
+			no-map;
+		};
+
+		/* Modem shared memory */
+		ram@06f00000 {
+			reg = <0x06f00000 0x00100000>;
+			no-map;
+		};
+
+		/* Modem private memory */
+		ram@07000000 {
+			reg = <0x07000000 0x01000000>;
+			no-map;
+		};
+
+		/*
+		 * Initial Secure Software ISSW memory
+		 *
+		 * This is probably only used if the kernel tries
+		 * to actually call into trustzone to run secure
+		 * applications, which the mainline kernel probably
+		 * will not do on this old chipset. But you can never
+		 * be too careful, so reserve this memory anyway.
+		 */
+		ram@17f00000 {
+			reg = <0x17f00000 0x00100000>;
+			no-map;
+		};
+	};
 };
diff --git a/arch/arm/boot/dts/ste-db8520.dtsi b/arch/arm/boot/dts/ste-db8520.dtsi
index 48bd8728ae27fd377931c2240883a050b56de517..287804e9e1836775364650c402bf01fdf4fcf742 100644
--- a/arch/arm/boot/dts/ste-db8520.dtsi
+++ b/arch/arm/boot/dts/ste-db8520.dtsi
@@ -12,4 +12,42 @@
 					    200000 0>;
 		};
 	};
+
+	reserved-memory {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges;
+
+		/* Modem trace memory */
+		ram@06000000 {
+			reg = <0x06000000 0x00f00000>;
+			no-map;
+		};
+
+		/* Modem shared memory */
+		ram@06f00000 {
+			reg = <0x06f00000 0x00100000>;
+			no-map;
+		};
+
+		/* Modem private memory */
+		ram@07000000 {
+			reg = <0x07000000 0x01000000>;
+			no-map;
+		};
+
+		/*
+		 * Initial Secure Software ISSW memory
+		 *
+		 * This is probably only used if the kernel tries
+		 * to actually call into trustzone to run secure
+		 * applications, which the mainline kernel probably
+		 * will not do on this old chipset. But you can never
+		 * be too careful, so reserve this memory anyway.
+		 */
+		ram@17f00000 {
+			reg = <0x17f00000 0x00100000>;
+			no-map;
+		};
+	};
 };
diff --git a/arch/arm/boot/dts/ste-db9500.dtsi b/arch/arm/boot/dts/ste-db9500.dtsi
new file mode 100644
index 0000000000000000000000000000000000000000..0afff703191c67a4efac243914e60028e8867a46
--- /dev/null
+++ b/arch/arm/boot/dts/ste-db9500.dtsi
@@ -0,0 +1,35 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "ste-dbx5x0.dtsi"
+
+/ {
+	cpus {
+		cpu@300 {
+			/* cpufreq controls */
+			operating-points = <1152000 0
+					    800000 0
+					    400000 0
+					    200000 0>;
+		};
+	};
+
+	reserved-memory {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges;
+
+		/*
+		 * Initial Secure Software ISSW memory
+		 *
+		 * This is probably only used if the kernel tries
+		 * to actually call into trustzone to run secure
+		 * applications, which the mainline kernel probably
+		 * will not do on this old chipset. But you can never
+		 * be too careful, so reserve this memory anyway.
+		 */
+		ram@17f00000 {
+			reg = <0x17f00000 0x00100000>;
+			no-map;
+		};
+	};
+};
diff --git a/arch/arm/boot/dts/ste-snowball.dts b/arch/arm/boot/dts/ste-snowball.dts
index be90e73c923ec255e156996f1b0990f5d37886c4..27d8a07718a001c31b9f38ef21c6c2f33b12425f 100644
--- a/arch/arm/boot/dts/ste-snowball.dts
+++ b/arch/arm/boot/dts/ste-snowball.dts
@@ -4,7 +4,7 @@
  */
 
 /dts-v1/;
-#include "ste-db8500.dtsi"
+#include "ste-db9500.dtsi"
 #include "ste-href-ab8500.dtsi"
 #include "ste-href-family-pinctrl.dtsi"