API for the Dreamcast's system calls More...

Topics
	GDROM System Calls
	GDROM Syscalls and Data Types

	dcload system calls
	API for dcload's system calls

Files
file	syscalls.h
	Functions to access the system calls of the Dreamcast ROM.

Data Structures
struct	cd_check_drive_status_t
	Status filled by Check Drive syscall. More...

struct	cd_read_params_t
	Params for READ commands. More...

struct	cd_toc_t
	TOC structure returned by the BIOS. More...

struct	cd_cmd_toc_params_t
	Params for GETTOC commands. More...

struct	cd_cmd_play_params_t
	Params for PLAY command. More...

struct	cd_cmd_getscd_params_t
	Params for GETSCD command. More...

struct	cd_cmd_chk_status_t
	GDROM Command Extra Status. More...

struct	cd_sec_mode_params_t
	Sector mode params. More...

struct	cd_transfer_params_t
	Parameters for transfer. More...

Functions
void	syscall_sysinfo_init (void)
	Inits data needed by sysinfo id/icon.

int	syscall_sysinfo_icon (uint32_t icon, uint8_t *dest)
	Reads an icon from the flashrom.

uint64_t	syscall_sysinfo_id (void)
	Reads the ID of the Dreamcast.

uint8_t *	syscall_font_address (void)
	Gets the romfont address.

int	syscall_font_lock (void)
	Locks access to ROM font.

void	syscall_font_unlock (void)
	Unlocks access to ROM font.

int	syscall_flashrom_info (uint32_t part, void *info)
	Gets info on partition in the flashrom.

int	syscall_flashrom_read (uint32_t pos, void *dest, size_t n)
	Read data from the flashrom.

int	syscall_flashrom_write (uint32_t pos, const void *src, size_t n)
	Write data to the flashrom.

int	syscall_flashrom_delete (uint32_t pos)
	Delete a partition of the flashrom.

int	syscall_misc_init (void)
	Initializes all the syscall vectors.

int	syscall_misc_setvector (uint32_t super, uintptr_t handler)
	Set/Clear a user defined super function.

void	syscall_system_reset (void) __noreturn
	Resets the Dreamcast.

void	syscall_system_bios_menu (void) __noreturn
	Go to the BIOS menu.

void	syscall_system_cd_menu (void) __noreturn
	Exit to CD menu.

Detailed Description

API for the Dreamcast's system calls

This module encapsulates all the system calls available in the Dreamcast BIOS, allowing direct interaction with system hardware components such as the GDROM drive, flash ROM, and bios fonts. These functions are essential for performing low-level operations that are not handled by standard user-space APIs.

Function Documentation

◆ syscall_flashrom_delete()

int syscall_flashrom_delete ( uint32_t pos )

Delete a partition of the flashrom.

This function returns a flashrom partition to all 1's, so that it may be rewritten.

Warning: ALL data in the entire partition will be lost.

Parameters

pos	The offset from the start of the flashrom you want to delete.

Return values

0	On success.
-1	On failure.

See also: syscall_flashrom_read(), syscall_flashrom_write()

◆ syscall_flashrom_info()

int syscall_flashrom_info	(	uint32_t	part,
		void *	info )

Gets info on partition in the flashrom.

This function fetches the info of a partition in the flashrom.

Parameters

part	The partition number (0-4).
info	The buffer to store info (8 bytes in size).

Return values

0	On success.
-1	On failure.

◆ syscall_flashrom_read()

int syscall_flashrom_read	(	uint32_t	pos,
		void *	dest,
		size_t	n )

Read data from the flashrom.

This function reads data from an offset into the flashrom to the destination buffer.

Parameters

pos	The read start position into the flashrom.
dest	The destination buffer.
n	The number of bytes to read.

Returns: Number of bytes read on success, or -1 on failure.

See also: syscall_flashrom_write(), syscall_flashrom_delete()

◆ syscall_flashrom_write()

int syscall_flashrom_write	(	uint32_t	pos,
		const void *	src,
		size_t	n )

Write data to the flashrom.

This function writes data to an offset into the flashrom from the source buffer.

Warning: It is only possible to overwrite 1's with 0's. 0's can not be written back to 1's so general overwriting is therefore not possible. You would need to delete a whole partition to overwrite it.

Parameters

pos	The start position to write into the flashrom.
src	The source buffer.
n	The number of bytes to write.

Returns: Number of bytes written on success, or -1 on failure.

See also: syscall_flashrom_read(), syscall_flashrom_delete()

◆ syscall_font_address()

uint8_t * syscall_font_address ( void )

Gets the romfont address.

This function returns the address of the ROM font.

Warning: Before attempting to access the font data, you should always call syscall_font_lock() to ensure that you have exclusive access to the G1 BUS the ROM is located on. Call syscall_font_unlock() when you're done accessing the data.

Note: Defined in syscall_font.s

Returns: The address of the font.

◆ syscall_font_lock()

int syscall_font_lock ( void )

Locks access to ROM font.

This function tries to lock a mutex for exclusive access to the ROM font. This is needed because you can't access the BIOS font during G1 DMA.

Note: Defined in syscall_font.s

Return values

0	On success.
-1	On failure.

See also: syscall_font_unlock()

◆ syscall_font_unlock()

void syscall_font_unlock ( void )

Unlocks access to ROM font.

This function releases the mutex locked with syscall_font_lock().

Note: Defined in syscall_font.s

See also: syscall_font_lock()

◆ syscall_misc_init()

int syscall_misc_init ( void )

Initializes all the syscall vectors.

This function initializes all the syscall vectors to their default values.

Returns: 0

◆ syscall_misc_setvector()

int syscall_misc_setvector	(	uint32_t	super,
		uintptr_t	handler )

Set/Clear a user defined super function.

This function sets/clears the handler for one of the seven user defined super functions. Setting a handler is only allowed if it not currently set.

Parameters

super	The super function number (1-7).
handler	The pointer to handler function, or NULL to clear.

Return values

0	On success.
-1	On failure.

◆ syscall_sysinfo_icon()

int syscall_sysinfo_icon	(	uint32_t	icon,
		uint8_t *	dest )

Reads an icon from the flashrom.

This function reads an icon from the flashrom into a destination buffer.

Note: The format of these icons is not known.

Parameters

icon	The icon number (0-9, 5-9 seems to really be icons).
dest	The destination buffer (704 bytes in size).

Returns: Number of bytes read on success, or -1 on failure.

◆ syscall_sysinfo_id()

uint64_t syscall_sysinfo_id ( void )

Reads the ID of the Dreamcast.

This function returns the unique 64-bit ID for the Dreamcast.

Returns: The Dreamcast ID.

◆ syscall_sysinfo_init()

void syscall_sysinfo_init ( void )

Inits data needed by sysinfo id/icon.

Note: This is called automatically by KOS during initialization. This function prepares syscall_sysinfo_icon and syscall_sysinfo_id calls for use by copying the relevant data from the system flashrom into 8C000068-8C00007F.

◆ syscall_system_bios_menu()

void syscall_system_bios_menu ( void )

Go to the BIOS menu.

This function exits the program to the BIOS menu.

Referenced by cd::returnToBios().

◆ syscall_system_cd_menu()

void syscall_system_cd_menu ( void )

Exit to CD menu.

This function exits the program to the BIOS CD menu.

◆ syscall_system_reset()

void syscall_system_reset ( void )

Resets the Dreamcast.

This function soft resets the Dreamcast console.

Topics

Files

Data Structures

Functions

Detailed Description

Function Documentation

◆ syscall_flashrom_delete()

◆ syscall_flashrom_info()

◆ syscall_flashrom_read()

◆ syscall_flashrom_write()

◆ syscall_font_address()

◆ syscall_font_lock()

◆ syscall_font_unlock()

◆ syscall_misc_init()

◆ syscall_misc_setvector()

◆ syscall_sysinfo_icon()

◆ syscall_sysinfo_id()

◆ syscall_sysinfo_init()

◆ syscall_system_bios_menu()

◆ syscall_system_cd_menu()

◆ syscall_system_reset()