arch: call init and preinit array

arch/at91sam3x8e/CMakeLists.txt

@@ -12,6 +12,7 @@ configure_file(
 )
 
 target_sources(ardix_arch PRIVATE
+	arch_init.c
 	atom_get_put.S
 	atom.c
 	atomic.c

arch/at91sam3x8e/arch_init.c

@@ -0,0 +1,29 @@
+/* See the end of this file for copyright, license, and warranty information. */
+
+#include <ardix/malloc.h>
+#include <toolchain.h>
+
+/* flash.ld */
+extern uint32_t _sheap;
+extern uint32_t _eheap;
+
+#include <arch/debug.h>
+
+void __preinit_malloc(void)
+{
+	malloc_init(&_sheap, (size_t)&_eheap - (size_t)&_sheap);
+}
+__preinit_call(__preinit_malloc);
+
+/*
+ * This file is part of Ardix.
+ * Copyright (c) 2020, 2021 Felix Kopp <owo@fef.moe>.
+ *
+ * Ardix is non-violent software: you may only use, redistribute,
+ * and/or modify it under the terms of the CNPLv6+ as found in
+ * the LICENSE file in the source code root directory or at
+ * <https://git.pixie.town/thufie/CNPL>.
+ *
+ * Ardix comes with ABSOLUTELY NO WARRANTY, to the extent
+ * permitted by applicable law.  See the CNPLv6+ for details.
+ */

arch/at91sam3x8e/handle_reset.c

@@ -2,6 +2,7 @@
 
 #include <arch/hardware.h>
 #include <arch/interrupt.h>
+#include <arch/linker.h>
 #include <arch-generic/hardware.h>
 
 #include <ardix/malloc.h>
@@ -11,19 +12,6 @@
 #include <string.h>
 #include <toolchain.h>
 
-/* from flash.ld */
-extern uint32_t _sfixed;	/* fixed area start */
-extern uint32_t _efixed;	/* fixed area end */
-extern uint32_t _etext;		/* program (.text) end */
-extern uint32_t _srelocate;	/* relocate (.data) start */
-extern uint32_t _erelocate;	/* relocate end */
-extern uint32_t _szero;		/* zero area (.bss) start */
-extern uint32_t _ezero;		/* zero area end */
-extern uint32_t _sstack;	/* stack start */
-extern uint32_t _estack;	/* stack end */
-extern uint32_t _sheap;		/* heap start */
-extern uint32_t _eheap;		/* heap end */
-
 /* implementation in init/main.c */
 extern int main(void);
 
@@ -34,8 +22,11 @@ __naked __noreturn void handle_reset(void)
 	memmove(&_srelocate, &_etext, (size_t)(&_erelocate) - (size_t)(&_srelocate));
 	memset(&_szero, 0, (size_t)(&_ezero) - (size_t)(&_szero));
 
-	/* memory protection isn't implemented yet, heap is shared among all processes */
-	malloc_init(&_sheap, (size_t)(&_eheap) - (size_t)(&_sheap));
+	for (uint32_t *fn = &__preinit_array_start; fn != &__preinit_array_end; fn++)
+		( (void (*)(void))fn )();
+
+	for (uint32_t *fn = &__init_array_start; fn != &__init_array_end; fn++)
+		( (void (*)(void))fn )();
 
 	/* start the Kernel */
 	main();

arch/at91sam3x8e/include/arch/linker.h

@@ -0,0 +1,78 @@
+/* See the end of this file for copyright, license, and warranty information. */
+
+#pragma once
+
+#include <stdint.h>
+
+/**
+ * @file linker.h
+ * @brief External symbols defined by the linker script (see flash.ld).
+ * The declarations in this file don't carry an actual value and cannot be
+ * accessed directly; they are merely there to get the *addresses* of.
+ */
+
+/** @brief Start of fixed area */
+extern uint32_t _sfixed;
+/** @brief End of fixed area */
+extern uint32_t _efixed;
+
+/** @brief End of program code (.text) */
+extern uint32_t _etext;
+
+/** @brief Start of relocation section (for global and static variables) */
+extern uint32_t _srelocate;
+/** @brief End of relocation section */
+extern uint32_t _erelocate;
+
+/** @brief Start of zero area (.bss) */
+extern uint32_t _szero;
+/** @brief End of zero area (.bss) */
+extern uint32_t _ezero;
+
+/**
+ * @brief Lowest address of the main (kernel) stack.
+ * This is technically the end of the stack, because it grows
+ * from the highest address downwards.
+ */
+extern uint32_t _sstack;
+/** @brief Highest address if the main (kernel) stack. */
+extern uint32_t _estack;
+
+/** @brief Start of heap area */
+extern uint32_t _sheap;
+/** @brief End of heap area */
+extern uint32_t _eheap;
+
+/**
+ * @brief Start of preinit array.
+ * The preinit array is an array of function pointers that are invoked before
+ * the ones in the init array and `main()` are called.  Only the most critical
+ * setup routines, like initializing the memory allocator, should go here.
+ */
+extern uintptr_t __preinit_array_start;
+/** @brief End of preinit array. */
+extern uintptr_t __preinit_array_end;
+
+/**
+ * @brief Start of init array.
+ * The init array is an array of function pointers that are invoked before
+ * calling `main()` and are there to initialize the various components of the
+ * standard C library.  They are executed after the preinit array, so memory
+ * allocation is already available.
+ */
+extern uint32_t __init_array_start;
+/** @brief End of init array. */
+extern uint32_t __init_array_end;
+
+/*
+ * This file is part of Ardix.
+ * Copyright (c) 2020, 2021 Felix Kopp <owo@fef.moe>.
+ *
+ * Ardix is non-violent software: you may only use, redistribute,
+ * and/or modify it under the terms of the CNPLv6+ as found in
+ * the LICENSE file in the source code root directory or at
+ * <https://git.pixie.town/thufie/CNPL>.
+ *
+ * Ardix comes with ABSOLUTELY NO WARRANTY, to the extent
+ * permitted by applicable law.  See the CNPLv6+ for details.
+ */