diff --git a/boards/sifive/hifive_unleashed/Kconfig.hifive_unleashed b/boards/sifive/hifive_unleashed/Kconfig.hifive_unleashed
index 2fc2f15..da445a3 100644
--- a/boards/sifive/hifive_unleashed/Kconfig.hifive_unleashed
+++ b/boards/sifive/hifive_unleashed/Kconfig.hifive_unleashed
@@ -2,4 +2,5 @@
 # SPDX-License-Identifier: Apache-2.0
 
 config BOARD_HIFIVE_UNLEASHED
-	select SOC_SIFIVE_FREEDOM_FU540
+	select SOC_SIFIVE_FREEDOM_FU540_E51 if BOARD_HIFIVE_UNLEASHED_FU540_E51
+	select SOC_SIFIVE_FREEDOM_FU540_U54 if BOARD_HIFIVE_UNLEASHED_FU540_U54
diff --git a/boards/sifive/hifive_unleashed/doc/index.rst b/boards/sifive/hifive_unleashed/doc/index.rst
index 6479117..e6450ac 100644
--- a/boards/sifive/hifive_unleashed/doc/index.rst
+++ b/boards/sifive/hifive_unleashed/doc/index.rst
@@ -15,9 +15,21 @@
 Applications for the ``hifive_unleashed`` board configuration can be built as
 usual (see :ref:`build_an_application`) using the corresponding board name:
 
-.. zephyr-app-commands::
-   :board: hifive_unleashed
-   :goals: build
+.. tabs::
+
+   .. group-tab:: E51
+
+      .. zephyr-app-commands::
+         :zephyr-app: samples/hello_world
+         :board: hifive_unleashed/fu540/e51
+         :goals: build
+
+   .. group-tab:: U54
+
+      .. zephyr-app-commands::
+         :zephyr-app: samples/hello_world
+         :board: hifive_unleashed/fu540/u54
+         :goals: build
 
 Flashing
 ========
diff --git a/boards/sifive/hifive_unleashed/hifive_unleashed.dts b/boards/sifive/hifive_unleashed/hifive_unleashed.dtsi
similarity index 100%
rename from boards/sifive/hifive_unleashed/hifive_unleashed.dts
rename to boards/sifive/hifive_unleashed/hifive_unleashed.dtsi
diff --git a/boards/sifive/hifive_unleashed/hifive_unleashed_e51.dts b/boards/sifive/hifive_unleashed/hifive_unleashed_e51.dts
new file mode 100644
index 0000000..567fb97
--- /dev/null
+++ b/boards/sifive/hifive_unleashed/hifive_unleashed_e51.dts
@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2024 Antmicro <www.antmicro.com>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+/dts-v1/;
+
+#include "hifive_unleashed.dtsi"
+
+/ {
+
+	cpus {
+		cpu@1 {
+			status = "disabled";
+		};
+
+		cpu@2 {
+			status = "disabled";
+		};
+
+		cpu@3 {
+			status = "disabled";
+		};
+
+		cpu@4 {
+			status = "disabled";
+		};
+	};
+
+};
diff --git a/boards/sifive/hifive_unleashed/hifive_unleashed.yaml b/boards/sifive/hifive_unleashed/hifive_unleashed_e51.yaml
similarity index 76%
rename from boards/sifive/hifive_unleashed/hifive_unleashed.yaml
rename to boards/sifive/hifive_unleashed/hifive_unleashed_e51.yaml
index 1fb91e4..74d0161 100644
--- a/boards/sifive/hifive_unleashed/hifive_unleashed.yaml
+++ b/boards/sifive/hifive_unleashed/hifive_unleashed_e51.yaml
@@ -1,5 +1,5 @@
-identifier: hifive_unleashed
-name: SiFive HiFive Unleashed
+identifier: hifive_unleashed/fu540/e51
+name: SiFive HiFive Unleashed (E51)
 type: mcu
 arch: riscv
 toolchain:
@@ -8,11 +8,11 @@
 simulation: renode
 simulation_exec: renode
 testing:
+  timeout_multiplier: 6
   ignore_tags:
     - net
     - bluetooth
     - flash
-    - newlib
     - crypto
   renode:
     uart: sysbus.uart0
diff --git a/boards/sifive/hifive_unleashed/hifive_unleashed_defconfig b/boards/sifive/hifive_unleashed/hifive_unleashed_e51_defconfig
similarity index 100%
rename from boards/sifive/hifive_unleashed/hifive_unleashed_defconfig
rename to boards/sifive/hifive_unleashed/hifive_unleashed_e51_defconfig
diff --git a/boards/sifive/hifive_unleashed/hifive_unleashed_u54.dts b/boards/sifive/hifive_unleashed/hifive_unleashed_u54.dts
new file mode 100644
index 0000000..53af3e2
--- /dev/null
+++ b/boards/sifive/hifive_unleashed/hifive_unleashed_u54.dts
@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2024 Antmicro <www.antmicro.com>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/dts-v1/;
+
+#include "hifive_unleashed.dtsi"
+
+/ {
+	cpus {
+		cpu@0 {
+			status = "disabled";
+		};
+	};
+};
diff --git a/boards/sifive/hifive_unleashed/hifive_unleashed.yaml b/boards/sifive/hifive_unleashed/hifive_unleashed_u54.yaml
similarity index 76%
copy from boards/sifive/hifive_unleashed/hifive_unleashed.yaml
copy to boards/sifive/hifive_unleashed/hifive_unleashed_u54.yaml
index 1fb91e4..54b15bb 100644
--- a/boards/sifive/hifive_unleashed/hifive_unleashed.yaml
+++ b/boards/sifive/hifive_unleashed/hifive_unleashed_u54.yaml
@@ -1,5 +1,5 @@
-identifier: hifive_unleashed
-name: SiFive HiFive Unleashed
+identifier: hifive_unleashed/fu540/u54
+name: SiFive HiFive Unleashed (U54)
 type: mcu
 arch: riscv
 toolchain:
@@ -8,11 +8,11 @@
 simulation: renode
 simulation_exec: renode
 testing:
+  timeout_multiplier: 6
   ignore_tags:
     - net
     - bluetooth
     - flash
-    - newlib
     - crypto
   renode:
     uart: sysbus.uart0
diff --git a/boards/sifive/hifive_unleashed/hifive_unleashed_u54_defconfig b/boards/sifive/hifive_unleashed/hifive_unleashed_u54_defconfig
new file mode 100644
index 0000000..21f7ae2
--- /dev/null
+++ b/boards/sifive/hifive_unleashed/hifive_unleashed_u54_defconfig
@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: Apache-2.0
+
+CONFIG_CONSOLE=y
+CONFIG_GPIO=y
+CONFIG_SERIAL=y
+CONFIG_UART_SIFIVE_PORT_0=y
+CONFIG_UART_CONSOLE=y
+CONFIG_XIP=n
+CONFIG_RV_BOOT_HART=1
+CONFIG_FLOAT_HARD=y
diff --git a/boards/sifive/hifive_unleashed/support/openocd_hifive_unleashed.cfg b/boards/sifive/hifive_unleashed/support/openocd_hifive_unleashed.cfg
index 1620f6c..f809228 100644
--- a/boards/sifive/hifive_unleashed/support/openocd_hifive_unleashed.cfg
+++ b/boards/sifive/hifive_unleashed/support/openocd_hifive_unleashed.cfg
@@ -18,5 +18,9 @@
 target create $_TARGETNAME.4 riscv -chain-position $_TARGETNAME -coreid 4
 target smp $_TARGETNAME.0 $_TARGETNAME.1 $_TARGETNAME.2 $_TARGETNAME.3 $_TARGETNAME.4
 $_TARGETNAME.0 configure -work-area-phys 0x80000000 -work-area-size 0x4000 -work-area-backup 1
+$_TARGETNAME.1 configure -work-area-phys 0x80000000 -work-area-size 0x4000 -work-area-backup 1
+$_TARGETNAME.2 configure -work-area-phys 0x80000000 -work-area-size 0x4000 -work-area-backup 1
+$_TARGETNAME.3 configure -work-area-phys 0x80000000 -work-area-size 0x4000 -work-area-backup 1
+$_TARGETNAME.4 configure -work-area-phys 0x80000000 -work-area-size 0x4000 -work-area-backup 1
 
 flash bank onboard_spi_flash0 fespi 0x20000000 0 0 0 $_TARGETNAME.0 0x10040000
diff --git a/dts/riscv/sifive/riscv64-fu540.dtsi b/dts/riscv/sifive/riscv64-fu540.dtsi
index bc9c14e..065870f 100644
--- a/dts/riscv/sifive/riscv64-fu540.dtsi
+++ b/dts/riscv/sifive/riscv64-fu540.dtsi
@@ -32,14 +32,80 @@
 		#address-cells = <1>;
 		#size-cells = <0>;
 
-		cpu: cpu@0 {
+		cpu@0 {
 			compatible = "sifive,e51", "riscv";
 			device_type = "cpu";
-			reg = <0>;
+			i-cache-line-size = <0x4000>;
+			reg = <0x0>;
 			riscv,isa = "rv64imac_zicsr_zifencei";
-			status = "okay";
+			hlic0: interrupt-controller {
+				compatible = "riscv,cpu-intc";
+				#address-cells = <0>;
+				#interrupt-cells = <1>;
+				interrupt-controller;
+			};
+		};
 
-			hlic: interrupt-controller {
+		cpu@1 {
+			compatible = "sifive,u54", "riscv";
+			device_type = "cpu";
+			mmu-type = "riscv,sv39";
+			i-cache-line-size = <0x8000>;
+			d-cache-line-size = <0x8000>;
+			reg = <0x1>;
+			riscv,isa = "rv64gc";
+			hlic1: interrupt-controller {
+				compatible = "riscv,cpu-intc";
+				#address-cells = <0>;
+				#interrupt-cells = <1>;
+				interrupt-controller;
+			};
+		};
+
+		cpu@2 {
+			clock-frequency = <0>;
+			compatible = "sifive,u54", "riscv";
+			device_type = "cpu";
+			mmu-type = "riscv,sv39";
+			i-cache-line-size = <0x8000>;
+			d-cache-line-size = <0x8000>;
+			reg = <0x2>;
+			riscv,isa = "rv64gc";
+			hlic2: interrupt-controller {
+				compatible = "riscv,cpu-intc";
+				#address-cells = <0>;
+				#interrupt-cells = <1>;
+				interrupt-controller;
+			};
+		};
+
+		cpu@3 {
+			clock-frequency = <0>;
+			compatible = "sifive,u54", "riscv";
+			device_type = "cpu";
+			mmu-type = "riscv,sv39";
+			i-cache-line-size = <0x8000>;
+			d-cache-line-size = <0x8000>;
+			reg = <0x3>;
+			riscv,isa = "rv64gc";
+			hlic3: interrupt-controller {
+				compatible = "riscv,cpu-intc";
+				#address-cells = <0>;
+				#interrupt-cells = <1>;
+				interrupt-controller;
+			};
+		};
+
+		cpu@4 {
+			clock-frequency = <0>;
+			compatible = "sifive,u54", "riscv";
+			device_type = "cpu";
+			mmu-type = "riscv,sv39";
+			i-cache-line-size = <0x8000>;
+			d-cache-line-size = <0x8000>;
+			reg = <0x4>;
+			riscv,isa = "rv64gc";
+			hlic4: interrupt-controller {
 				compatible = "riscv,cpu-intc";
 				#address-cells = <0>;
 				#interrupt-cells = <1>;
@@ -102,9 +168,17 @@
 			reg-names = "mem";
 		};
 
+
 		clint: clint@2000000 {
 			compatible = "sifive,clint0";
-			interrupts-extended = <&hlic 3 &hlic 7>;
+			interrupts-extended = <&hlic0 3 &hlic0 7
+							&hlic1 3 &hlic1 7
+							&hlic2 3 &hlic2 7
+							&hlic3 3 &hlic3 7
+							&hlic4 3 &hlic4 7>;
+			interrupt-names = "soft0", "timer0", "soft1", "timer1",
+							"soft2", "timer2", "soft3", "timer3",
+							"soft4", "timer4";
 			reg = <0x2000000 0x10000>;
 		};
 
@@ -116,10 +190,14 @@
 
 		plic: interrupt-controller@c000000 {
 			compatible = "sifive,plic-1.0.0";
-			#address-cells = <0>;
 			#interrupt-cells = <2>;
+			#address-cells = <1>;
 			interrupt-controller;
-			interrupts-extended = <&hlic 11>;
+			interrupts-extended = <&hlic0 11
+							&hlic1 11 &hlic1 9
+							&hlic2 11 &hlic2 9
+							&hlic3 11 &hlic3 9
+							&hlic4 11 &hlic4 9>;
 			reg = <0x0c000000 0x04000000>;
 			riscv,max-priority = <7>;
 			riscv,ndev = <52>;
diff --git a/samples/drivers/jesd216/sample.yaml b/samples/drivers/jesd216/sample.yaml
index afc3b20..85f6c07 100644
--- a/samples/drivers/jesd216/sample.yaml
+++ b/samples/drivers/jesd216/sample.yaml
@@ -15,7 +15,8 @@
   sample.drivers.jesd216:
     platform_exclude:
       - hifive1
-      - hifive_unleashed
+      - hifive_unleashed/fu540/e51
+      - hifive_unleashed/fu540/u54
       - hifive_unmatched
       - mimxrt1170_evk/mimxrt1176/cm7
       - mimxrt1170_evk/mimxrt1176/cm4
diff --git a/soc/sifive/sifive_freedom/fu500/Kconfig b/soc/sifive/sifive_freedom/fu500/Kconfig
index 9e39923..fb54b74 100644
--- a/soc/sifive/sifive_freedom/fu500/Kconfig
+++ b/soc/sifive/sifive_freedom/fu500/Kconfig
@@ -23,3 +23,8 @@
 	select SOC_EARLY_INIT_HOOK
 	select INCLUDE_RESET_VECTOR
 	imply XIP
+
+config SOC_SIFIVE_FREEDOM_FU540_U54
+	bool
+	select RISCV_ISA_EXT_G
+	select CPU_HAS_FPU_DOUBLE_PRECISION
diff --git a/soc/sifive/sifive_freedom/fu500/Kconfig.defconfig b/soc/sifive/sifive_freedom/fu500/Kconfig.defconfig
index 4db8701..e7aafaa 100644
--- a/soc/sifive/sifive_freedom/fu500/Kconfig.defconfig
+++ b/soc/sifive/sifive_freedom/fu500/Kconfig.defconfig
@@ -25,4 +25,10 @@
 config NUM_IRQS
 	default 64
 
+config FPU
+	default y if CPU_HAS_FPU
+
+config RISCV_IMPRECISE_FPU_STATE_TRACKING
+	default y if FPU
+
 endif # SOC_SERIES_SIFIVE_FREEDOM_FU500
diff --git a/soc/sifive/sifive_freedom/fu500/Kconfig.soc b/soc/sifive/sifive_freedom/fu500/Kconfig.soc
index 87a9e6d..08eb6ac 100644
--- a/soc/sifive/sifive_freedom/fu500/Kconfig.soc
+++ b/soc/sifive/sifive_freedom/fu500/Kconfig.soc
@@ -5,12 +5,20 @@
 	bool
 	select SOC_FAMILY_SIFIVE_FREEDOM
 
-config SOC_SERIES
-	default "fu500" if SOC_SERIES_SIFIVE_FREEDOM_FU500
-
 config SOC_SIFIVE_FREEDOM_FU540
 	bool
 	select SOC_SERIES_SIFIVE_FREEDOM_FU500
 
+config SOC_SIFIVE_FREEDOM_FU540_E51
+	bool
+	select SOC_SIFIVE_FREEDOM_FU540
+
+config SOC_SIFIVE_FREEDOM_FU540_U54
+	bool
+	select SOC_SIFIVE_FREEDOM_FU540
+
+config SOC_SERIES
+	default "fu500" if SOC_SERIES_SIFIVE_FREEDOM_FU500
+
 config SOC
-	default "fu540" if SOC_SIFIVE_FREEDOM_FU540
+	default "fu540" if SOC_SIFIVE_FREEDOM_FU540_E51 || SOC_SIFIVE_FREEDOM_FU540_U54
diff --git a/soc/sifive/sifive_freedom/soc.yml b/soc/sifive/sifive_freedom/soc.yml
index 1590d49..9f0d3f1 100644
--- a/soc/sifive/sifive_freedom/soc.yml
+++ b/soc/sifive/sifive_freedom/soc.yml
@@ -7,6 +7,9 @@
       - name: fu500
         socs:
           - name: fu540
+            cpuclusters:
+              - name: e51
+              - name: u54
       - name: fu700
         socs:
           - name: fu740
diff --git a/tests/drivers/console/line_splitting/testcase.yaml b/tests/drivers/console/line_splitting/testcase.yaml
index 05567a7..a0c74f3 100644
--- a/tests/drivers/console/line_splitting/testcase.yaml
+++ b/tests/drivers/console/line_splitting/testcase.yaml
@@ -2,7 +2,7 @@
   tags:
     - drivers
     - console
-  platform_allow: hifive1 hifive_unleashed
+  platform_allow: hifive1 hifive_unleashed/fu540/e51
   harness: robot
 
 tests:
diff --git a/tests/subsys/zbus/integration/testcase.yaml b/tests/subsys/zbus/integration/testcase.yaml
index e856b41..9443c61 100644
--- a/tests/subsys/zbus/integration/testcase.yaml
+++ b/tests/subsys/zbus/integration/testcase.yaml
@@ -3,7 +3,8 @@
     platform_exclude:
       - m2gl025_miv
       - qemu_cortex_a9
-      - hifive_unleashed
+      - hifive_unleashed/fu540/e51
+      - hifive_unleashed/fu540/u54
       - fvp_base_revc_2xaemv8a/fvp_base_revc_2xaemv8a/smp/ns
     tags: zbus
     integration_platforms: