Uniform device tree for differnt core configs

Instead of having multiple device tree files for differnt number of cores, a single file is used. The device tree must be processes by a C/C++ preprocessor before it is compiled. NRCPU must be passed to the preprocessor. The compilation of the device trees is shifted from buildroot to the postprocessing step. Signed-off-by: Nils Bosbach <bosbach@ice.rwth-aachen.de>
aut0 · Nov 9, 2023 · e73f33e · e73f33e
1 parent 78c4750
commit e73f33e
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diff --git a/linux/files/avp64-linux-defconfig b/linux/files/avp64-linux-defconfig
@@ -28,8 +28,6 @@ BR2_LINUX_KERNEL_CUSTOM_VERSION=y
 BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="4.19.4"
 BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG=y
 BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="/app/files/avp64_linux_kernel.config"
-BR2_LINUX_KERNEL_DTS_SUPPORT=y
-BR2_LINUX_KERNEL_CUSTOM_DTS_PATH="/app/files/avp64_linux.dts /app/files/avp64_linux_dualcore.dts"
 BR2_PACKAGE_BUSYBOX_SHOW_OTHERS=y
 BR2_PACKAGE_GDB=y
 BR2_PACKAGE_STRACE=y

diff --git a/linux/files/avp64_linux_dualcore.dts b/linux/files/avp64_linux_dualcore.dts
diff --git a/linux/files/dt/Makefile b/linux/files/dt/Makefile
@@ -0,0 +1,35 @@
+O   ?= .
+CPP ?= cpp
+DTC ?= dtc
+
+CPPFLAGS := -nostdinc -undef -x assembler-with-cpp
+
+OBJ := ${O}/avp64x1.dtb ${O}/avp64x2.dtb ${O}/avp64x4.dtb ${O}/avp64x8.dtb
+
+all: $(OBJ)
+
+clean:
+	$(RM) $(OBJ)
+
+${O}/%.dtb: ${O}/%.dts
+	@mkdir -p ${O}
+	$(DTC) -I dts -O dtb -o $@ $<
+
+${O}/avp64x1.dts: avp64.dts
+	@mkdir -p ${O}
+	$(CPP) $(CPPFLAGS) -D NRCPU=1 -o $@ $<
+
+${O}/avp64x2.dts: avp64.dts
+	@mkdir -p ${O}
+	$(CPP) $(CPPFLAGS) -D NRCPU=2 -o $@ $<
+
+${O}/avp64x4.dts: avp64.dts
+	@mkdir -p ${O}
+	$(CPP) $(CPPFLAGS) -D NRCPU=4 -o $@ $<
+
+${O}/avp64x8.dts: avp64.dts
+	@mkdir -p ${O}
+	$(CPP) $(CPPFLAGS) -D NRCPU=8 -o $@ $<
+
+.PHONY: all clean
+.INTERMEDIATE: $(OBJ:dtb=dts)
diff --git a/linux/files/avp64_linux.dts → linux/files/dt/avp64.dts b/linux/files/avp64_linux.dts → linux/files/dt/avp64.dts
@@ -1,6 +1,6 @@
 /******************************************************************************
  *                                                                            *
- * Copyright 2020 Lukas Jünger                                                *
+ * Copyright 2023 Lukas Jünger, Nils Bosbach                                  *
  *                                                                            *
  * Licensed under the Apache License, Version 2.0 (the "License");            *
  * you may not use this file except in compliance with the License.           *
@@ -16,6 +16,10 @@
  *                                                                            *
  ******************************************************************************/
 
+#ifndef NRCPU
+#error NRCPU undefined
+#endif
+
 /dts-v1/;
 
 / {
@@ -42,6 +46,61 @@
 			reg = <0x0 0x0>;
 		};
 
+#if NRCPU > 1
+		cpu1: cpu@1 {
+			device_type = "cpu";
+			compatible = "arm,armv8";
+			enable-method = "spin-table";
+			cpu-release-addr = <0x0 0x00004000>;
+			reg = <0x0 0x1>;
+		};
+#if NRCPU > 2
+		cpu2: cpu@2 {
+			device_type = "cpu";
+			compatible = "arm,armv8";
+			enable-method = "spin-table";
+			cpu-release-addr = <0x0 0x00004000>;
+			reg = <0x0 0x2>;
+		};
+		cpu3: cpu@3 {
+			device_type = "cpu";
+			compatible = "arm,armv8";
+			enable-method = "spin-table";
+			cpu-release-addr = <0x0 0x00004000>;
+			reg = <0x0 0x3>;
+		};
+#if NRCPU > 4
+		cpu4: cpu@4 {
+			device_type = "cpu";
+			compatible = "arm,armv8";
+			enable-method = "spin-table";
+			cpu-release-addr = <0x0 0x00004000>;
+			reg = <0x0 0x4>;
+		};
+		cpu5: cpu@5 {
+			device_type = "cpu";
+			compatible = "arm,armv8";
+			enable-method = "spin-table";
+			cpu-release-addr = <0x0 0x00004000>;
+			reg = <0x0 0x5>;
+		};
+		cpu6: cpu@6 {
+			device_type = "cpu";
+			compatible = "arm,armv8";
+			enable-method = "spin-table";
+			cpu-release-addr = <0x0 0x00004000>;
+			reg = <0x0 0x6>;
+		};
+		cpu7: cpu@7 {
+			device_type = "cpu";
+			compatible = "arm,armv8";
+			enable-method = "spin-table";
+			cpu-release-addr = <0x0 0x00004000>;
+			reg = <0x0 0x7>;
+		};
+#endif // NRCPU > 4
+#endif // NRCPU > 2
+#endif // NRCPU > 1
 	};
 
 	chosen {
@@ -148,14 +207,13 @@ amba {
 			};
 		};
 
-		gpio0: gpio@0x10149000 {
+		gpio0: gpio@10149000 {
 			compatible = "brcm,bcm6345-gpio";
 			reg = <0x10149000 4>;
 			reg-names = "dat";
 			gpio-controller;
 			#gpio-cells = <2>;
-			//big-endian;
-		};	
+		};
 	};
 
 	v2m_clk24mhz: clk24mhz {

diff --git a/linux/files/post-image.sh b/linux/files/post-image.sh
@@ -29,3 +29,6 @@ genimage \
   --inputpath "${BINARIES_DIR}" \
   --outputpath "${BINARIES_DIR}" \
   --config "${GENIMAGE_CFG}"
+
+# compile device trees
+make -C /app/files/dt O=/app/build/buildroot/output/dt