arch.h File Reference

Dreamcast architecture specific options. More...

#include <kos/cdefs.h>
#include <dc/video.h>

Go to the source code of this file.

Macros
#define	PAGESIZE   4096
	Page size (for MMU)
#define	PAGESIZE_BITS   12
	Bits for page size.
#define	PAGEMASK   (PAGESIZE - 1)
	Mask for page offset.
#define	page_count   ((16*1024*1024 - 0x10000) / PAGESIZE)
	Page count "variable".
#define	page_phys_base   0x8c010000
	Base address of available physical pages.
#define	HZ   100
	Number of timer ticks per second.
#define	THD_STACK_SIZE   32768
	Default thread stack size.
#define	DEFAULT_VID_MODE   DM_640x480
	Default video mode.
#define	DEFAULT_PIXEL_MODE   PM_RGB565
	Default pixel mode for video.
#define	DEFAULT_SERIAL_BAUD   57600
	Default serial bitrate.
#define	DEFAULT_SERIAL_FIFO   1
	Default serial FIFO behavior.
#define	ELF_SYM_PREFIX   "_"
	Global symbol prefix in ELF files.
#define	ELF_SYM_PREFIX_LEN   1
	Length of global symbol prefix in ELF files.
#define	ARCH_EXIT_RETURN   1
	Return to loader.
#define	ARCH_EXIT_MENU   2
	Return to system menu.
#define	ARCH_EXIT_REBOOT   3
	Reboot the machine.
#define	KOS_INIT_FLAGS(flags)   uint32 __kos_init_flags = (flags)
	Use this macro to determine the level of initialization you'd like in your program by default.
#define	KOS_INIT_ROMDISK(rd)   void * __kos_romdisk = (rd)
	Define a romdisk for your program, if you'd like one.
#define	KOS_INIT_ROMDISK_NONE   NULL
	State that you don't want a romdisk.
#define	INIT_DEFAULT   (INIT_IRQ | INIT_THD_PREEMPT)
	Default init flags (IRQs on, preemption enabled).
#define	INIT_NONE   0x0000
	Don't init optional things.
#define	INIT_IRQ   0x0001
	Enable IRQs at startup.
#define	INIT_THD_PREEMPT   0x0002
	Enable thread preemption.
#define	INIT_NET   0x0004
	Enable built-in networking.
#define	INIT_MALLOCSTATS   0x0008
	Enable malloc statistics.
#define	INIT_QUIET   0x0010
	Disable dbgio.
#define	INIT_OCRAM   0x10000
	Use half of the dcache as RAM.
#define	INIT_NO_DCLOAD   0x20000
	Disable dcload.
#define	arch_sleep()
	Dreamcast specific sleep mode "function".
#define	arch_get_ret_addr()
	DC specific "function" to get the return address from the current function.
#define	arch_get_fptr()
	DC specific "function" to get the frame pointer from the current function.
#define	arch_fptr_ret_addr(fptr)   (*((uint32*)fptr))
	Pass in a frame pointer value to get the return address for the given frame.
#define	arch_fptr_next(fptr)   (*((uint32*)(fptr+4)))
	Pass in a frame pointer value to get the previous frame pointer for the given frame.
#define	arch_valid_address(ptr)   ((ptr_t)(ptr) >= 0x8c010000 && (ptr_t)(ptr) < 0x8d000000)
	Returns true if the passed address is likely to be valid. Doesn't have to be exact, just a sort of general idea.

Functions
void	panic (const char *str) __noreturn
	Panic function.
int	arch_main ()
	Kernel C-level entry point.
void	arch_set_exit_path (int path)
	Set the exit path.
void	arch_exit () __noreturn
	Generic kernel "exit" point.
void	arch_return () __noreturn
	Kernel "return" point.
void	arch_abort () __noreturn
	Kernel "abort" point.
void	arch_reboot () __noreturn
	Kernel "reboot" call.
void	arch_menu () __noreturn
	Kernel "exit to menu" call.
void	arch_ctors ()
	Call to run all ctors.
void	arch_dtors ()
	Call to run all dtors.
void	__crtend_pullin ()
	Hook to ensure linking of crtend.c.
int	mm_init ()
	Initialize the memory management system.
void *	mm_sbrk (unsigned long increment)
	Request more core memory from the system.
void	arch_real_exit () __noreturn
	Jump back to the bootloader.
int	hardware_sys_init ()
	Initialize bare-bones hardware systems.
int	hardware_periph_init ()
	Initialize some peripheral systems.
void	hardware_shutdown ()
	Shut down hardware that was initted.
const char *	kos_get_banner (void)
	Retrieve the banner printed at program initialization.
const char *	kos_get_license (void)
	Retrieve the license information for the compiled copy of KOS.
const char *	kos_get_authors (void)
	Retrieve a list of authors and the dates of their contributions.

Variables
uint32	__kos_init_flags
	The init flags. Do not modify this directly!
void *	__kos_romdisk
	Built-in romdisk. Do not modify this directly!

---

Detailed Description

Dreamcast architecture specific options.

This file has various architecture specific options defined in it. Also, any functions that start with arch_ are in here.

Author:

Dan Potter

---

Macro Definition Documentation

#define arch_fptr_next

(

fptr

)

(*((uint32*)(fptr+4)))

Pass in a frame pointer value to get the previous frame pointer for the given frame.

Parameters:

fptr	The frame pointer to look at.

Returns:

The previous frame pointer.

#define arch_fptr_ret_addr

(

fptr

)

(*((uint32*)fptr))

Pass in a frame pointer value to get the return address for the given frame.

Parameters:

fptr	The frame pointer to look at.

Returns:

The return address of the pointer.

#define arch_get_fptr

(

)

Value:

({ \
        uint32 fp; \
        __asm__ __volatile__("mov       r14,%0\n" \
                             : "=&z" (fp) \
                             : /* no inputs */ \
                             : "memory" ); \
        fp; })

DC specific "function" to get the frame pointer from the current function.

Returns:

The frame pointer from the current function.

Note:

This only works if you don't disable frame pointers.

#define arch_get_ret_addr

(

)

Value:

({ \
        uint32 pr; \
        __asm__ __volatile__("sts       pr,%0\n" \
                             : "=&z" (pr) \
                             : /* no inputs */ \
                             : "memory" ); \
        pr; })

DC specific "function" to get the return address from the current function.

Returns:

The return address of the current function.

#define arch_sleep

(

)

Value:

do { \
        __asm__ __volatile__("sleep"); \
    } while(0)

Dreamcast specific sleep mode "function".

#define arch_valid_address

(

ptr

)

((ptr_t)(ptr) >= 0x8c010000 && (ptr_t)(ptr) < 0x8d000000)

Returns true if the passed address is likely to be valid. Doesn't have to be exact, just a sort of general idea.

Returns:

Whether the address is valid or not for normal memory access.

#define DEFAULT_PIXEL_MODE   PM_RGB565

Default pixel mode for video.

#define DEFAULT_SERIAL_BAUD   57600

Default serial bitrate.

#define DEFAULT_SERIAL_FIFO   1

Default serial FIFO behavior.

#define DEFAULT_VID_MODE   DM_640x480

Default video mode.

#define ELF_SYM_PREFIX   "_"

Global symbol prefix in ELF files.

#define ELF_SYM_PREFIX_LEN   1

Length of global symbol prefix in ELF files.

#define HZ   100

Number of timer ticks per second.

#define KOS_INIT_FLAGS

(

flags

)

uint32 __kos_init_flags = (flags)

Use this macro to determine the level of initialization you'd like in your program by default.

The defaults line will be fine for most things.

Parameters:

flags

Parts of KOS to init.

#define KOS_INIT_ROMDISK

(

rd

)

void * __kos_romdisk = (rd)

Define a romdisk for your program, if you'd like one.

Parameters:

rd	Pointer to the romdisk image in your code.

#define KOS_INIT_ROMDISK_NONE   NULL

State that you don't want a romdisk.

#define page_count   ((16*1024*1024 - 0x10000) / PAGESIZE)

Page count "variable".

The number of pages is static, so we can optimize this quite a bit.

#define page_phys_base   0x8c010000

Base address of available physical pages.

#define PAGEMASK   (PAGESIZE - 1)

Mask for page offset.

#define PAGESIZE   4096

Page size (for MMU)

#define PAGESIZE_BITS   12

Bits for page size.

#define THD_STACK_SIZE   32768

Default thread stack size.

---

Function Documentation

void __crtend_pullin

(

)

Hook to ensure linking of crtend.c.

void arch_abort

(

)

Kernel "abort" point.

Note:

This function will never return!

void arch_ctors

(

)

Call to run all ctors.

void arch_dtors

(

)

Call to run all dtors.

void arch_exit

(

)

Generic kernel "exit" point.

Note:

This function will never return!

int arch_main

(

)

Kernel C-level entry point.

Returns:

The program's return value.

void arch_menu

(

)

Kernel "exit to menu" call.

Note:

This function will never return!

void arch_real_exit

(

)

Jump back to the bootloader.

You generally shouldn't use this function, but rather use arch_exit() or exit() instead.

Note:

This function will never return!

void arch_reboot

(

)

Kernel "reboot" call.

Note:

This function will never return!

void arch_return

(

)

Kernel "return" point.

Note:

This function will never return!

void arch_set_exit_path

(

int

path

)

Set the exit path.

The default, if you don't call this, is ARCH_EXIT_RETURN.

Parameters:

path	What arch_exit() should do.

See also:

Potential exit paths from the kernel on

int hardware_periph_init

(

)

Initialize some peripheral systems.

This will be done automatically for you on start by the default arch_main(), so you shouldn't have to deal with this yourself.

Return values:

0	On success (no error conditions defined).

void hardware_shutdown

(

)

Shut down hardware that was initted.

This function will shut down anything initted with hardware_sys_init() and hardware_periph_init(). This will be done for you automatically by the various exit points, so you shouldn't have to do this yourself.

int hardware_sys_init

(

)

Initialize bare-bones hardware systems.

This will be done automatically for you on start by the default arch_main(), so you shouldn't have to deal with this yourself.

Return values:

0	On success (no error conditions defined).

const char* kos_get_authors

(

void

)

Retrieve a list of authors and the dates of their contributions.

This function retrieves the copyright information for the version of KOS in use. This function can be used to add such information to the credits of programs using KOS to give the appropriate credit to those that have worked on KOS.

Remember, you do need to give credit where credit is due, and this is an easy way to do so. ;-)

Return values:

A	pointer to the authors' copyright information.

const char* kos_get_banner

(

void

)

Retrieve the banner printed at program initialization.

This function retrieves the banner string that is printed at initialization time by the kernel. This contains the version of KOS in use and basic information about the environment in which it was compiled.

Return values:

A	pointer to the banner string.

const char* kos_get_license

(

void

)

Retrieve the license information for the compiled copy of KOS.

This function retrieves a string containing the license terms that the version of KOS in use is distributed under. This can be used to easily add information to your program to be displayed at runtime.

Return values:

A	pointer to the license terms.

int mm_init

(

)

Initialize the memory management system.

Return values:

0	On success (no error conditions defined).

void* mm_sbrk

(

unsigned long

increment

)

Request more core memory from the system.

Parameters:

increment

The number of bytes requested.

Returns:

A pointer to the memory.

Note:

This function will panic if no memory is available.

void panic

(

const char *

str

)

Panic function.

This function will cause a kernel panic, printing the specified message.

Parameters:

str	The error message to print.

Note:

This function will never return!

---

Variable Documentation

uint32 __kos_init_flags

The init flags. Do not modify this directly!

void* __kos_romdisk

Built-in romdisk. Do not modify this directly!