dts: stm32: update m4_rproc to support the remoteproc OPTEE framework

Update device tree to support the load of the remoteproc firmware by OPTEE.
- declare m_ipc_shm memory region that can contain the remote processor
  resource table and trace buffer,
- update reset to align declaration with the Linux devicetree

To enable the load of the coprocessor firmware by OP-TEE, user have
to update the m4_rproc node compatible property:
-"st,stm32mp1-m4": the load is managed by Linux or U-boot,
-"st,stm32mp1-m4-tee": the load is managed by OP-TEE.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>

core/arch/arm/dts/stm32mp151.dtsi

@@ -1839,8 +1839,8 @@
 			reg = <0x10000000 0x40000>,
 			      <0x30000000 0x40000>,
 			      <0x38000000 0x10000>;
-			resets = <&rcc MCU_R>;
-			st,syscfg-holdboot = <&rcc 0x10C 0x1>;
+			resets = <&rcc MCU_R>, <&rcc MCU_HOLD_BOOT_R>;
+			reset-names = "mcu_rst", "hold_boot";
 			st,syscfg-tz = <&rcc 0x000 0x1>;
 			st,syscfg-pdds = <&pwr_mcu 0x0 0x1>;
 			st,syscfg-rsc-tbl = <&tamp 0x144 0xFFFFFFFF>;

core/arch/arm/dts/stm32mp157c-ed1.dts

@@ -54,6 +54,12 @@
 			no-map;
 		};
 
+		ipc_shmem: ipc-shmem@1004f000 {
+			compatible = "shared-dma-pool";
+			reg = <0x10048000 0x8000>;
+			no-map;
+		};
+
 		mcuram: mcuram@30000000 {
 			compatible = "shared-dma-pool";
 			reg = <0x30000000 0x40000>;
@@ -324,7 +330,7 @@
 
 &m4_rproc {
 	memory-region = <&retram>, <&mcuram>, <&mcuram2>, <&vdev0vring0>,
-			<&vdev0vring1>, <&vdev0buffer>;
+			<&vdev0vring1>, <&vdev0buffer>, <&ipc_shmem>;
 	mboxes = <&ipcc 0>, <&ipcc 1>, <&ipcc 2>, <&ipcc 3>;
 	mbox-names = "vq0", "vq1", "shutdown", "detach";
 	interrupt-parent = <&exti>;

core/arch/arm/dts/stm32mp15xx-dkx.dtsi

@@ -42,6 +42,12 @@
 			no-map;
 		};
 
+		ipc_shmem: ipc-shmem@1004f000 {
+			compatible = "shared-dma-pool";
+			reg = <0x10048000 0x8000>;
+			no-map;
+		};
+
 		mcuram: mcuram@30000000 {
 			compatible = "shared-dma-pool";
 			reg = <0x30000000 0x40000>;
@@ -476,7 +482,7 @@
 
 &m4_rproc {
 	memory-region = <&retram>, <&mcuram>, <&mcuram2>, <&vdev0vring0>,
-			<&vdev0vring1>, <&vdev0buffer>;
+			<&vdev0vring1>, <&vdev0buffer>, <&ipc_shmem>;
 	mboxes = <&ipcc 0>, <&ipcc 1>, <&ipcc 2>, <&ipcc 3>;
 	mbox-names = "vq0", "vq1", "shutdown", "detach";
 	interrupt-parent = <&exti>;