Fallback to FreeBIOS when BIOS files are not found. (v2) (#1174)

* Fallback to FreeBIOS when BIOS files are not found.

* Add sources of drastic bios files.

* Move FreeBIOS/external BIOS choice to configuration option/checkbox.

* Fix indentation

Co-authored-by: Filippo Scognamiglio <flscogna@gmail.com>
Co-authored-by: Filippo Scognamiglio <filippo.scognamiglio@felgo.com>

freebios/Makefile

@@ -0,0 +1,17 @@
+TC_PREFIX  = /home/exophase/pandora-dev
+PREFIX     = $(TC_PREFIX)/arm-2011.03
+AS         = $(PREFIX)/bin/arm-none-linux-gnueabi-gcc
+OBJCOPY    = $(PREFIX)/bin/arm-none-linux-gnueabi-objcopy
+
+BIN_ARM7   = drastic_bios_arm7
+BIN_ARM9   = drastic_bios_arm9
+
+all:
+	$(AS) bios_common.S -DBIOS_ARM7 -march=armv4 -c -Wa,-asl=$(BIN_ARM7).list -o $(BIN_ARM7).o
+	$(AS) bios_common.S -DBIOS_ARM9 -march=armv5 -c -Wa,-asl=$(BIN_ARM9).list -o $(BIN_ARM9).o
+	$(OBJCOPY) -O binary $(BIN_ARM7).o $(BIN_ARM7).bin
+	$(OBJCOPY) -O binary $(BIN_ARM9).o $(BIN_ARM9).bin
+
+clean:
+	rm -f $(BIN_ARM7).bin $(BIN_ARM7).o $(BIN_ARM9).bin $(BIN_ARM9).o
+

freebios/drastic_bios_readme.txt

@@ -0,0 +1,36 @@
+Custom NDS ARM7/ARM9 BIOS replacement
+Copyright (c) 2013, Gilead Kutnick
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are met:
+
+1) Redistributions of source code must retain the above copyright notice,
+   this list of conditions and the following disclaimer.
+2) Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
+
+-- Info --
+
+This archive contains source code and assembly for a custom BIOS replacement
+for the Nintendo DS system. This code is in no way affiliated with Nintendo
+and is not derived from Nintendo's BIOS implementation but has been implemented
+using publically available documentation.
+
+It can be assembled using the included Makefile along with a proper ARM gcc
+toolchain. Change the first four lines to point to the proper toolchain of your
+choice.
+