sg3d: Initial implementation for the Stargate 3DS

Fork of ace3ds_sd.

Key differences:
- No XOR at end of write flush command
- Scrambler does not start during write buffer transfer

source/sg3d/Makefile

@@ -0,0 +1,132 @@
+#---------------------------------------------------------------------------------
+.SUFFIXES:
+#---------------------------------------------------------------------------------
+
+ifeq ($(strip $(DEVKITARM)),)
+$(error "Please set DEVKITARM in your environment. export DEVKITARM=<path to>devkitARM")
+endif
+
+include $(DEVKITARM)/ds_rules
+
+#---------------------------------------------------------------------------------
+# TARGET is the name of the output
+# BUILD is the directory where object files & intermediate files will be placed
+# SOURCES is a list of directories containing source code
+# DATA is a list of directories containing data files
+# INCLUDES is a list of directories containing header files
+# SPECS is the directory containing the important build and link files
+#---------------------------------------------------------------------------------
+export TARGET		:=	$(shell basename $(CURDIR))
+BUILD		:=	build
+SOURCES		:=	source ../../common_source
+DATA		:=	data
+INCLUDES	:=	include ../../common_source
+
+
+#---------------------------------------------------------------------------------
+# options for code generation
+#---------------------------------------------------------------------------------
+ARCH	:=	-mthumb-interwork
+
+CFLAGS	:=	-g -Wall -O2\
+			-mcpu=arm7tdmi -mtune=arm7tdmi -fomit-frame-pointer\
+			-ffast-math -ffreestanding \
+			$(ARCH)
+
+CFLAGS	+=	$(INCLUDE) -DARM7 -fPIC
+
+CXXFLAGS	:= $(CFLAGS) -fno-rtti -fno-exceptions
+
+ASFLAGS	:=	-g $(ARCH) $(INCLUDE)
+LDFLAGS	=	-nostartfiles -nostdlib -T dldi.ld -g $(ARCH) -Wl,-Map,$(TARGET).map,--gc-sections -ffunction-sections -fdata-sections
+
+LIBS	:=
+
+#---------------------------------------------------------------------------------
+# list of directories containing libraries, this must be the top level containing
+# include and lib
+#---------------------------------------------------------------------------------
+LIBDIRS	:=	$(LIBNDS)
+
+
+#---------------------------------------------------------------------------------
+# no real need to edit anything past this point unless you need to add additional
+# rules for different file extensions
+#---------------------------------------------------------------------------------
+ifneq ($(BUILD),$(notdir $(CURDIR)))
+#---------------------------------------------------------------------------------
+
+export OUTPUT	:=	$(CURDIR)/$(TARGET)
+
+export VPATH	:=	$(foreach dir,$(SOURCES),$(CURDIR)/$(dir)) \
+			$(foreach dir,$(DATA),$(CURDIR)/$(dir))
+
+export DEPSDIR	:=	$(CURDIR)/$(BUILD)
+
+CFILES		:=	$(foreach dir,$(SOURCES),$(notdir $(wildcard $(dir)/*.c)))
+CPPFILES	:=	$(foreach dir,$(SOURCES),$(notdir $(wildcard $(dir)/*.cpp)))
+SFILES		:=	$(foreach dir,$(SOURCES),$(notdir $(wildcard $(dir)/*.s)))
+BINFILES	:=	$(foreach dir,$(DATA),$(notdir $(wildcard $(dir)/*.*)))
+
+#---------------------------------------------------------------------------------
+# use CXX for linking C++ projects, CC for standard C
+#---------------------------------------------------------------------------------
+ifeq ($(strip $(CPPFILES)),)
+#---------------------------------------------------------------------------------
+	export LD	:=	$(CC)
+#---------------------------------------------------------------------------------
+else
+#---------------------------------------------------------------------------------
+	export LD	:=	$(CXX)
+#---------------------------------------------------------------------------------
+endif
+#---------------------------------------------------------------------------------
+
+export OFILES	:=	$(addsuffix .o,$(BINFILES)) \
+			$(CPPFILES:.cpp=.o) $(CFILES:.c=.o) $(SFILES:.s=.o)
+
+export INCLUDE	:=	$(foreach dir,$(INCLUDES),-I$(CURDIR)/$(dir)) \
+			$(foreach dir,$(LIBDIRS),-I$(dir)/include) \
+			-I$(CURDIR)/$(BUILD)
+
+export LIBPATHS	:=	$(foreach dir,$(LIBDIRS),-L$(dir)/lib)
+
+.PHONY: $(BUILD) clean all
+
+#---------------------------------------------------------------------------------
+all: $(BUILD)
+
+$(BUILD):
+	@[ -d $@ ] || mkdir -p $@
+	@$(MAKE) --no-print-directory -C $(BUILD) -f $(CURDIR)/Makefile
+
+#---------------------------------------------------------------------------------
+clean:
+	@echo clean ...
+	@rm -fr $(BUILD) $(TARGET).dldi $(TARGET).elf
+
+
+#---------------------------------------------------------------------------------
+else
+
+DEPENDS	:=	$(OFILES:.o=.d)
+
+#---------------------------------------------------------------------------------
+# main targets
+#---------------------------------------------------------------------------------
+$(OUTPUT).dldi	:	$(OUTPUT).elf
+$(OUTPUT).elf	:	$(OFILES)
+
+
+#---------------------------------------------------------------------------------
+%.dldi: %.elf
+	@$(OBJCOPY) -O binary $< $@
+	@echo built ... $(notdir $@)
+
+
+-include $(DEPENDS)
+
+
+#---------------------------------------------------------------------------------------
+endif
+#---------------------------------------------------------------------------------------

source/sg3d/source/dldi_header.s

@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: Zlib
+//
+// Copyright (C) 2006-2016 Michael Chisholm (Chishm)
+// Copyright (C) 2006-2016 Dave Murphy (WinterMute)
+
+#include <nds/arm9/dldi_asm.h>
+
+	.section ".crt0","ax"
+	.global _start
+	.align    4
+	.arm
+
+@ Driver patch file standard header -- 16 bytes
+
+	.word   0xBF8DA5ED      @ Magic number to identify this region
+	.asciz  " Chishm"       @ Identifying Magic string (8 bytes with null terminator)
+	.byte   0x01            @ Version number
+	.byte   DLDI_SIZE_4KB   @ Log [base-2] of the size of this driver in bytes.
+	.byte   FIX_GOT | FIX_BSS | FIX_GLUE    @ Sections to fix
+	.byte   0x00            @ Space allocated in the application, leave empty.
+
+@ Text identifier - can be anything up to 47 chars + terminating null -- 48 bytes
+
+	.align  4
+	.asciz  "Stargate 3DS"
+
+@ Offsets to important sections within the data -- 32 bytes
+
+	.align  6
+	.word   __text_start    @ data start
+	.word   __data_end      @ data end
+	.word   __glue_start    @ Interworking glue start -- Needs address fixing
+	.word   __glue_end      @ Interworking glue end
+	.word   __got_start     @ GOT start               -- Needs address fixing
+	.word   __got_end       @ GOT end
+	.word   __bss_start     @ bss start               -- Needs setting to zero
+	.word   __bss_end       @ bss end
+
+@ IO_INTERFACE data -- 32 bytes
+
+	.ascii  "SG3D"
+	.word   FEATURE_MEDIUM_CANREAD | FEATURE_MEDIUM_CANWRITE | FEATURE_SLOT_NDS
+	.word   startup         @ Function pointers to standard device driver functions
+	.word   is_inserted
+	.word   read_sectors
+	.word   write_sectors
+	.word   clear_status
+	.word   shutdown
+
+_start:
+
+	.align
+	.pool
+	.end

source/sg3d/source/io_sg3d.c

@@ -0,0 +1,58 @@
+/*
+	Stargate 3DS
+	Card IO routines
+
+	Copyright (C) 2023 lifehackerhansol
+
+	SPDX-License-Identifier: Zlib
+*/
+
+#include <nds/ndstypes.h>
+#include "io_sg3d.h"
+#include "libtwl_card.h"
+
+static inline void SG3D_ReadCardData(u64 command, u32 flags, void *buffer, u32 length)
+{
+	card_romSetCmd(command);
+	card_romStartXfer(flags, false);
+	if ((u32)buffer & 3)
+		card_romCpuReadUnaligned((u8 *)buffer, length);
+	else
+		card_romCpuRead(buffer, length);
+}
+
+static inline void SG3D_WriteCardData(u64 command, u32 flags, const void *buffer, u32 length)
+{
+	card_romSetCmd(command);
+	card_romStartXfer(flags, false);
+	if ((u32)buffer & 3)
+		card_romCpuWriteUnaligned((u8 *)buffer, length);
+	else
+		card_romCpuWrite(buffer, length);
+}
+
+static inline u32 SG3D_SendCommand(const u64 command)
+{
+	card_romSetCmd(command);
+	card_romStartXfer(SG3D_CTRL_READ_4B, false);
+	card_romWaitDataReady();
+	return card_romGetData();
+}
+
+void SG3D_SDReadSector(u32 sector, void *buffer)
+{
+	// wait until data is ready
+	// request should return 0 when ready to access
+	while(SG3D_SendCommand(SG3D_CMD_SD_READ_REQUEST(sector)));
+
+	SG3D_ReadCardData(SG3D_CMD_SD_READ_DATA, SG3D_CTRL_READ_512B, buffer, 128);
+}
+
+void SG3D_SDWriteSector(u32 sector, const void *buffer)
+{
+	SG3D_WriteCardData(SG3D_CMD_SD_WRITE_START(sector), SG3D_CTRL_WRITE_512B, buffer, 128);
+
+	// Wait until write finishes
+	// status should return 0 when done
+	while(SG3D_SendCommand(SG3D_CMD_SD_WRITE_STAT(sector)));
+}

source/sg3d/source/io_sg3d.h

@@ -0,0 +1,46 @@
+/*
+	Stargate 3DS
+	Card IO routines
+
+	Copyright (C) 2023 lifehackerhansol
+
+	SPDX-License-Identifier: Zlib
+*/
+
+#pragma once
+
+#include <nds/ndstypes.h>
+
+#ifndef NULL
+ #define NULL 0
+#endif
+
+// Stargate 3DS defines
+// Stargate 3DS MCCNT1 flags
+#define SG3D_CTRL_BASE       (MCCNT1_ENABLE | MCCNT1_RESET_OFF | MCCNT1_CMD_SCRAMBLE | MCCNT1_LATENCY2(0) | MCCNT1_LATENCY1(0))
+#define SG3D_CTRL_READ_4B    (SG3D_CTRL_BASE | MCCNT1_CLOCK_SCRAMBLER | MCCNT1_READ_DATA_DESCRAMBLE | MCCNT1_LEN_4)
+#define SG3D_CTRL_READ_512B  (SG3D_CTRL_BASE | MCCNT1_CLOCK_SCRAMBLER | MCCNT1_READ_DATA_DESCRAMBLE | MCCNT1_LEN_512)
+#define SG3D_CTRL_WRITE_512B (SG3D_CTRL_BASE | MCCNT1_DIR_WRITE | MCCNT1_LEN_512)
+
+// Stargate 3DS MCCMDs
+#define SG3D_CMD_SD_READ_DATA      (0xBAull << 56)
+
+static inline u64 SG3D_CMD_SD_READ_REQUEST(u32 sector)
+{
+	return (0xB9ull << 56) | ((u64)sector << 24);
+}
+
+static inline u64 SG3D_CMD_SD_WRITE_START(u32 sector)
+{
+	return (0xBBull << 56) | ((u64)sector << 24);
+}
+
+static inline u64 SG3D_CMD_SD_WRITE_STAT(u32 sector)
+{
+	u64 command = (0xBCull << 56) | ((u64)sector << 24);
+	return command;
+}
+
+// user API
+void SG3D_SDReadSector(u32 sector, void* buffer);
+void SG3D_SDWriteSector(u32 sector, const void* buffer);

source/sg3d/source/iointerface.c

@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: CC0-1.0
+//
+// SPDX-FileContributor: Antonio Niño Díaz, 2023
+// SPDX-FileContributor: lifehackerhansol, 2023
+
+#include <nds/ndstypes.h>
+
+#include "io_sg3d.h"
+#include "libtwl_card.h"
+
+// Initialize the driver. Returns true on success.
+bool startup(void)
+{
+	return true;
+}
+
+// Returns true if a card is present and initialized.
+bool is_inserted(void)
+{
+	return true;
+}
+
+// Reads 512 byte sectors into a buffer that may be unaligned. Returns true on
+// success.
+bool read_sectors(uint32_t sector, uint32_t num_sectors, void *buffer)
+{
+	for (int i = 0; i < num_sectors; i++)
+	{
+		SG3D_SDReadSector((sector + i), buffer);
+		buffer = (u8 *)buffer + 0x200;
+	}
+	return true;
+}
+
+// Writes 512 byte sectors from a buffer that may be unaligned. Returns true on
+// success.
+bool write_sectors(uint32_t sector, uint32_t num_sectors, const void *buffer)
+{
+	for (int i = 0; i < num_sectors; i++)
+	{
+		SG3D_SDWriteSector((sector + i), buffer);
+		buffer = (u8 *)buffer + 0x200;
+	}
+	return true;
+}
+
+// Clear error flags from the card. Returns true on success.
+bool clear_status(void)
+{
+	return true;
+}
+
+// Shutdowns the card. This may never be called.
+bool shutdown(void)
+{
+	return true;
+}