-changed up some booting code to hopefully fix those random freezes on game and homebrew bootup

resources/extldr/crt0.s

@@ -1,22 +1,76 @@
 # Copyright 2008-2009  Segher Boessenkool  <segher@kernel.crashing.org>
 # This code is licensed to you under the terms of the GNU GPL, version 2;
 # see file COPYING or http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt
+.set r0,0;		.set r1,1;		.set r2,2;		.set r3,3;		.set r4,4;
+.set r5,5;		.set r6,6;		.set r7,7;		.set r8,8;		.set r9,9;
+.set r10,10;	.set r11,11;	.set r12,12;	.set r13,13;	.set r14,14;
+.set r15,15;	.set r16,16;	.set r17,17;	.set r18,18;	.set r19,19;
+.set r20,20;	.set r21,21;	.set r22,22;	.set r23,23;	.set r24,24;
+.set r25,25;	.set r26,26;	.set r27,27;	.set r28,28;	.set r29,29;
+.set r30,30;	.set r31,31;
 
 .extern _main
 	.globl _start
 _start:
+	# Disable interrupts
+	mfmsr r3
+	rlwinm r3,r3,0,17,15
+	mtmsr r3
+	isync
 
-	# Disable interrupts, enable FP.
-	mfmsr 3 ; rlwinm 3,3,0,17,15 ; ori 3,3,0x2000 ; mtmsr 3 ; isync
-
-	# Setup stack.
-	lis 1,_stack_top@ha ; addi 1,1,_stack_top@l ; li 0,0 ; stwu 0,-64(1)
+	# Reset our registers
+	bl		__init_registers
 
 	# Clear BSS.
-	lis 3,__bss_start@ha ; addi 3,3,__bss_start@l
-	li 4,0
-	lis 5,__bss_end@ha ; addi 5,5,__bss_end@l ; sub 5,5,3
-	bl memset
+	lis		r3,__bss_start@h
+	ori		r3,r3,__bss_start@l
+	li		r4,0
+	lis		r5,__bss_end@h
+	ori		r5,r5,__bss_end@l
+	subf	r5,r3,r5
+	bl		_memset
 
 	# Go!
 	bl		_main
+
+#thanks to megazig for that
+__init_registers:
+	li      r0,0
+	li      r3,0
+	li      r4,0
+	li      r5,0
+	li      r6,0
+	li      r7,0
+	li      r8,0
+	li      r9,0
+	li      r10,0
+	li      r11,0
+	li      r12,0
+	li      r14,0
+	li      r15,0
+	li      r16,0
+	li      r17,0
+	li      r18,0
+	li      r19,0
+	li      r20,0
+	li      r21,0
+	li      r22,0
+	li      r23,0
+	li      r24,0
+	li      r25,0
+	li      r26,0
+	li      r27,0
+	li      r28,0
+	li      r29,0
+	li      r30,0
+	li      r31,0
+	lis     r1,__stack_top@h
+	ori     r1,r1,__stack_top@l
+	addi    r1,r1,-4
+	stw     r0,0(r1)
+	stwu    r1,-0x38(r1)
+	lis     r2,0
+	ori     r2,r2,0x8000
+	lis     r13,0
+	ori     r13,r13,0x8000
+	blr

resources/extldr/link.ld

@@ -22,6 +22,6 @@ SECTIONS {
 	. = ALIGN(0x40);
 	.stack : {
 		. += 0x8000;
-		_stack_top = .;
+		__stack_top = .;
 	}
 }

resources/extldr/main.c

@@ -1,5 +1,3 @@
-#include <stdio.h>
-#include <stdarg.h>
 #include "string.h"
 #include "sync.h"
 #include "usbgecko.h"
@@ -11,7 +9,7 @@ void _main(void)
 {
 	usbgecko_init();
 	gprintf("Copying External Booter...\n");
-	memcpy(start, buffer, 0xF0000); //960kb safe copying of booter
+	_memcpy(start, buffer, 0xF0000); //960kb safe copying of booter
 	sync_before_exec(start, 0xF0000);
 	gprintf("Done! Jumping to Entrypoint...\n");
 	exeEntryPoint();

resources/extldr/string.c

@@ -2,11 +2,9 @@
 // This code is licensed to you under the terms of the GNU GPL, version 2;
 // see file COPYING or http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt
 
-#include <stdio.h>
-
-void *memset(void *b, int c, size_t len)
+void * _memset(void *b, int c, unsigned int len)
 {
-	size_t i;
+	unsigned int i;
 
 	for (i = 0; i < len; i++)
 		((unsigned char *)b)[i] = c;
@@ -14,9 +12,9 @@ void *memset(void *b, int c, size_t len)
 	return b;
 }
 
-void *memcpy(void *dst, const void *src, size_t len)
+void * _memcpy(void *dst, const void *src, unsigned int len)
 {
-	size_t i;
+	unsigned int i;
 
 	for (i = 0; i < len; i++)
 		((unsigned char *)dst)[i] = ((unsigned char *)src)[i];

resources/extldr/string.h

@@ -1,9 +1,7 @@
 #ifndef STRING_H_
 #define STRING_H_
 
-#include <stdio.h>
-
-void *memcpy(void *dst, const void *src, size_t len);
-void *memset(void *b, int c, size_t len);
+void * _memcpy(void *dst, const void *src, unsigned int len);
+void * _memset(void *b, int c, unsigned int len);
 
 #endif

source/homebrew/homebrew.cpp

@@ -51,9 +51,18 @@ void AddBootArgument(const char * argv)
 
 bool LoadAppBooter(const char *filepath)
 {
-	appbooter_ptr = fsop_ReadFile(filepath, &appbooter_size);
-	if(appbooter_size == 0 || appbooter_ptr == NULL)
+	u8 *tmp_ptr = fsop_ReadFile(filepath, &appbooter_size);
+	if(appbooter_size == 0 || tmp_ptr == NULL)
 		return false;
+	appbooter_ptr = (u8*)MEM2_lo_alloc(appbooter_size); /* safety because upper mem2 is dol */
+	if(appbooter_ptr == NULL)
+	{
+		free(tmp_ptr);
+		return false;
+	}
+	memcpy(appbooter_ptr, tmp_ptr, appbooter_size);
+	DCFlushRange(appbooter_ptr, appbooter_size);
+	free(tmp_ptr);
 	return true;
 }
 
@@ -134,9 +143,21 @@ void BootHomebrew()
 	JumpToEntry(BOOTER_ENTRY);
 }
 
+extern "C" { extern void __exception_closeall(); }
+u32 AppEntrypoint = 0;
 void JumpToEntry(entry EntryPoint)
 {
-	gprintf("Jumping to %08x\n", EntryPoint);
-	SYS_ResetSystem(SYS_SHUTDOWN, 0, 0);
-	__lwp_thread_stopmultitasking(EntryPoint);
+	AppEntrypoint = (u32)EntryPoint;
+	gprintf("Jumping to %08x\n", AppEntrypoint);
+	u32 level = IRQ_Disable();
+	__IOS_ShutdownSubsystems();
+	__exception_closeall();
+	asm volatile (
+		"lis %r3, AppEntrypoint@h\n"
+		"ori %r3, %r3, AppEntrypoint@l\n"
+		"lwz %r3, 0(%r3)\n"
+		"mtlr %r3\n"
+		"blr\n"
+	);
+	IRQ_Restore(level);
 }