* Copyright 2008-2010, Ingo Weinhold, ingo_weinhold@gmx.de.
* Copyright 2008, Axel Dörfler, axeld@pinc-software.de.
* Distributed under the terms of the MIT License.
*/
#ifndef DMA_RESOURCES_H
#define DMA_RESOURCES_H
#include <sys/uio.h>
#include <fs_interface.h>
#include <lock.h>
#include <util/DoublyLinkedList.h>
#include <util/iovec_support.h>
struct device_node;
struct IOOperation;
struct IORequest;
struct dma_restrictions {
generic_addr_t low_address;
generic_addr_t high_address;
generic_size_t alignment;
generic_size_t boundary;
generic_size_t max_transfer_size;
uint32 max_segment_count;
generic_size_t max_segment_size;
uint32 flags;
};
struct DMABounceBuffer : public DoublyLinkedListLinkImpl<DMABounceBuffer> {
void* address;
phys_addr_t physical_address;
phys_size_t size;
};
typedef DoublyLinkedList<DMABounceBuffer> DMABounceBufferList;
class DMABuffer : public DoublyLinkedListLinkImpl<DMABuffer> {
public:
static DMABuffer* Create(size_t count);
generic_io_vec* Vecs() { return fVecs; }
generic_io_vec& VecAt(size_t index) { return fVecs[index]; }
uint32 VecCount() const { return fVecCount; }
void SetVecCount(uint32 count);
void AddVec(generic_addr_t base,
generic_size_t size);
void SetBounceBuffer(DMABounceBuffer* bounceBuffer)
{ fBounceBuffer = bounceBuffer; }
DMABounceBuffer* BounceBuffer() const { return fBounceBuffer; }
void* BounceBufferAddress() const
{ return fBounceBuffer
? fBounceBuffer->address : NULL; }
phys_addr_t PhysicalBounceBufferAddress() const
{ return fBounceBuffer
? fBounceBuffer->physical_address
: 0; }
phys_size_t BounceBufferSize() const
{ return fBounceBuffer
? fBounceBuffer->size : 0; }
bool UsesBounceBufferAt(uint32 index);
void Dump() const;
private:
DMABounceBuffer* fBounceBuffer;
uint32 fVecCount;
generic_io_vec fVecs[1];
};
typedef DoublyLinkedList<DMABuffer> DMABufferList;
class DMAResource {
public:
DMAResource();
~DMAResource();
status_t Init(const dma_restrictions& restrictions,
generic_size_t blockSize,
uint32 bufferCount,
uint32 bounceBufferCount);
status_t Init(device_node* node,
generic_size_t blockSize,
uint32 bufferCount,
uint32 bounceBufferCount);
status_t CreateBuffer(DMABuffer** _buffer);
status_t CreateBounceBuffer(DMABounceBuffer** _buffer);
status_t TranslateNext(IORequest* request,
IOOperation* operation,
generic_size_t maxOperationLength);
void RecycleBuffer(DMABuffer* buffer);
generic_size_t BlockSize() const { return fBlockSize; }
uint32 BufferCount() const { return fBufferCount; }
private:
bool _NeedsBoundsBuffers() const;
void _RestrictBoundaryAndSegmentSize(
generic_addr_t base,
generic_addr_t& length);
void _CutBuffer(DMABuffer& buffer,
phys_addr_t& physicalBounceBuffer,
phys_size_t& bounceLeft,
generic_size_t toCut);
phys_size_t _AddBounceBuffer(DMABuffer& buffer,
phys_addr_t& physicalBounceBuffer,
phys_size_t& bounceLeft,
generic_size_t length, bool fixedLength);
mutex fLock;
dma_restrictions fRestrictions;
generic_size_t fBlockSize;
uint32 fBufferCount;
uint32 fBounceBufferCount;
phys_size_t fBounceBufferSize;
DMABufferList fDMABuffers;
DMABounceBufferList fBounceBuffers;
generic_io_vec* fScratchVecs;
};
#endif
