// SPDX-License-Identifier: MIT
//
// Copyright (c) 2020-2021 Antonio Niño Díaz

#ifndef DMA_H__
#define DMA_H__

#include "definitions.h"

// Important note: The only DMA channel that can read from ROM is 3.

// Generic DMA transfer function. It is needed to start repeating transfers or
// anything other than a simple copy, as there are only helpers for simple
// copy scenarios.
//
// Returns 0 on success. A transfer can fail if:
// - The channel number isn't valid
// - the source address is set in ROM/SRAM and the specified channel isn't 3.
//   This check only works on GBA binaries.
EXPORT_API
int DMA_Transfer(int channel, const void *src, void *dst, size_t size,
                 uint16_t flags);

// Stop DMA transfers that repeat. Returns 0 on success.
EXPORT_API
int DMA_Stop(int channel);

// Copy from source to destination in 16-bit chunks. Returns 0 on success.
EXPORT_API
int DMA_Copy16(int channel, const void *src, void *dst, size_t size);

// Copy from source to destination in 32-bit chunks. Returns 0 on success.
EXPORT_API
int DMA_Copy32(int channel, const void *src, void *dst, size_t size);

// During the next HBL do a copy, in 16-bit chunks. Returns 0 on success.
EXPORT_API
int DMA_HBLCopy16(int channel, const void *src, void *dst, size_t size);

// During the next HBL do a copy, in 32-bit chunks. Returns 0 on success.
EXPORT_API
int DMA_HBLCopy32(int channel, const void *src, void *dst, size_t size);

// During the next VBL do a copy, in 16-bit chunks. Returns 0 on success.
EXPORT_API
int DMA_VBLCopy16(int channel, const void *src, void *dst, size_t size);

// During the next VBL do a copy, in 32-bit chunks. Returns 0 on success.
EXPORT_API
int DMA_VBLCopy32(int channel, const void *src, void *dst, size_t size);

#endif // DMA_H__