spu.h File Reference

Functions related to sound. More...

#include <sys/cdefs.h>
#include <arch/types.h>
#include <dc/g2bus.h>

Go to the source code of this file.

Typedefs
typedef g2_dma_callback_t	spu_dma_callback_t
	SPU DMA callback type. More...

Functions
void	spu_write_wait ()
	Waits for the sound FIFO to empty. More...
void	spu_memload (uint32 to, void *from, int length)
	Copy a block of data to sound RAM. More...
void	spu_memread (void *to, uint32 from, int length)
	Copy a block of data from sound RAM. More...
void	spu_memset (uint32 to, uint32 what, int length)
	Set a block of sound RAM to the specified value. More...
int	spu_dma_transfer (void *from, uint32 dest, uint32 length, int block, spu_dma_callback_t callback, ptr_t cbdata)
	Copy a block of data from SH4 RAM to sound RAM via DMA. More...
void	spu_enable ()
	Enable the SPU. More...
void	spu_disable ()
	Disable the SPU. More...
void	spu_cdda_volume (int left_volume, int right_volume)
	Set CDDA volume. More...
void	spu_cdda_pan (int left_pan, int right_pan)
	Set CDDA panning. More...
void	spu_master_mixer (int volume, int stereo)
	Set master mixer settings. More...
int	spu_init ()
	Initialize the SPU. More...
int	spu_shutdown ()
	Shutdown the SPU. More...
int	spu_dma_init ()
	Initialize SPU DMA support. More...
void	spu_dma_shutdown ()
	Shutdown SPU DMA support. More...

Detailed Description

Functions related to sound.

This file deals with memory transfers and the like for the sound hardware.

Author

Dan Potter

Typedef Documentation

typedef g2_dma_callback_t spu_dma_callback_t

SPU DMA callback type.

Function Documentation

void spu_cdda_pan	(	int	left_pan,
		int	right_pan
	)

Set CDDA panning.

Valid values are from 0-31. 16 is centered.

Parameters

left_pan	Pan of the left channel.
right_pan	Pan of the right channel.

void spu_cdda_volume	(	int	left_volume,
		int	right_volume
	)

Set CDDA volume.

Valid volume values are 0-15.

Parameters

left_volume	Volume of the left channel.
right_volume	Volume of the right channel.

void spu_disable

(

)

Disable the SPU.

This function resets all sound channels and puts the ARM in a reset state.

int spu_dma_init

(

)

Initialize SPU DMA support.

This function sets up the DMA support for transfers to the sound RAM area.

Return values

0	On success (no error conditions defined).

void spu_dma_shutdown

(

)

Shutdown SPU DMA support.

int spu_dma_transfer	(	void *	from,
		uint32	dest,
		uint32	length,
		int	block,
		spu_dma_callback_t	callback,
		ptr_t	cbdata
	)

Copy a block of data from SH4 RAM to sound RAM via DMA.

This function sets up a DMA transfer from main RAM to the sound RAM with G2 DMA.

Parameters

from	A pointer in main RAM to transfer from. Must be 32-byte aligned.
dest	Offset in sound RAM to transfer to. Do not include the 0xA0800000 part, its implied. Must be 32-byte aligned.
length	Number of bytes to copy. Must be a multiple of 32.
block	1 if you want to wait for the transfer to complete, 0 otherwise (use the callback for this case).
callback	Function to call when the DMA completes. Can be NULL if you don't want to have a callback. This will be called in an interrupt context, so keep that in mind when writing the function.
cbdata	Data to pass to the callback function.

Return values

-1	On failure. Sets errno as appropriate.
0	On success.

Error Conditions:

EINVAL - Invalid channel
EFAULT - from or dest is not aligned
EIO - I/O error

void spu_enable

(

)

Enable the SPU.

This function resets all sound channels and lets the ARM out of reset.

int spu_init

(

)

Initialize the SPU.

This function will reset the SPU, clear the sound RAM, reinit the CDDA support and run an infinite loop on the ARM.

Return values

0	On success (no error conditions defined).

void spu_master_mixer	(	int	volume,
		int	stereo
	)

Set master mixer settings.

This function sets the master mixer volume and mono/stereo setting.

Parameters

volume	The volume to set (0-15).
stereo	1 for stereo output, 0 for mono.

void spu_memload	(	uint32	to,
		void *	from,
		int	length
	)

Copy a block of data to sound RAM.

This function acts much like memcpy() but copies to the sound RAM area.

Parameters

to	The offset in sound RAM to copy to. Do not include the 0xA0800000 part, it is implied.
from	A pointer to copy from.
length	The number of bytes to copy. Automatically rounded up to be a multiple of 4.

void spu_memread	(	void *	to,
		uint32	from,
		int	length
	)

Copy a block of data from sound RAM.

This function acts much like memcpy() but copies from the sound RAM area.

Parameters

to	A pointer to copy to.
from	The offset in sound RAM to copy from. Do not include the 0xA0800000 part, it is implied.
length	The number of bytes to copy. Automatically rounded up to be a multiple of 4.

void spu_memset	(	uint32	to,
		uint32	what,
		int	length
	)

Set a block of sound RAM to the specified value.

This function acts like memset4(), setting the specified block of sound RAM to the given 32-bit value.

Parameters

to	The offset in sound RAM to set at. Do not include the 0xA0800000 part, it is implied.
what	The value to set.
length	The number of bytes to copy. Automatically rounded up to be a multiple of 4.

int spu_shutdown

(

)

Shutdown the SPU.

This function disables the SPU and clears sound RAM.

Return values

0	On success (no error conditions defined).

void spu_write_wait

(

)

Waits for the sound FIFO to empty.