ptos: ke: Add kernel C groundwork

Signed-off-by: Chloe M. <chloe@yiffware.org>

service/ptos/Makefile

@@ -9,7 +9,11 @@
 include ../mk/ptos.mk
 
 .PHONY: all
-all: machine
+all: ke machine
+
+.PHONY: ke
+ke:
+	cd ke/; $(MAKE) $(PASSDOWN_ARGS)
 
 .PHONY: machine
 machine:

service/ptos/arch/amd64/cpu/locore.S

@@ -15,6 +15,7 @@ MdBspEntry:
 
     lea g_GDTR(%rip), %rdi
     call MdGdtLoad
+    call KiKernelInit   /* Kick off system init */
 1:  hlt
     jmp 1b
 

service/ptos/ke/Makefile

@@ -0,0 +1,32 @@
+#
+# Copyright (c) 2026, Chloe M.
+# Provided under the BSD-3 clause
+#
+# Description:  Kernel executive build script
+# Author:		Chloe M.
+#
+
+.SILENT:
+include ../../mk/ptos.mk
+
+CFILES = $(shell find . -name "*.c")
+DFILES = $(CFILES:.c=.d)
+OFILES = $(CFILES:.c=.o)
+
+CFLAGS =							   \
+	$(SYS_CFLAGS)					   \
+	-MMD							   \
+	-D_KERNEL						   \
+	-DPRINTF_DISABLE_SUPPORT_PTRDIFF_T \
+	-DPRINTF_DISABLE_SUPPORT_FLOAT	   \
+	-I../xt/flanterm/src			   \
+	-I../head						   \
+	-I../target						   \
+	-I$(PT_PROJECT_ROOT)/sdk/head
+
+.PHONY: all
+all: $(OFILES)
+
+%.o: %.c
+	$(PROMPT) "CC" $<
+	$(SYS_CC) -c $(CFLAGS) $< -o $@

service/ptos/ke/init.c

@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) 2026, Chloe M., et al
+ * Provided under the BSD-3 clause.
+ *
+ * Description:  System bringup core
+ * Author:       Chloe M.
+ */
+
+#include <ptdef.h>
+
+/*
+ * Starting here is where the world is brought up and system
+ * components are initialized.
+ */
+VOID
+KiKernelInit(VOID)
+{
+}