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diff --git a/arch/arm/mach-bcmring/include/mach/dma.h b/arch/arm/mach-bcmring/include/mach/dma.h
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@@ -0,0 +1,826 @@
+/*****************************************************************************
+* Copyright 2004 - 2008 Broadcom Corporation. All rights reserved.
+*
+* Unless you and Broadcom execute a separate written software license
+* agreement governing use of this software, this software is licensed to you
+* under the terms of the GNU General Public License version 2, available at
+* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
+*
+* Notwithstanding the above, under no circumstances may you combine this
+* software in any way with any other Broadcom software provided under a
+* license other than the GPL, without Broadcom's express prior written
+* consent.
+*****************************************************************************/
+
+/****************************************************************************/
+/**
+* @file dma.h
+*
+* @brief API definitions for the linux DMA interface.
+*/
+/****************************************************************************/
+
+#if !defined(ASM_ARM_ARCH_BCMRING_DMA_H)
+#define ASM_ARM_ARCH_BCMRING_DMA_H
+
+/* ---- Include Files ---------------------------------------------------- */
+
+#include <linux/kernel.h>
+#include <linux/wait.h>
+#include <linux/semaphore.h>
+#include <csp/dmacHw.h>
+#include <mach/timer.h>
+#include <linux/scatterlist.h>
+#include <linux/dma-mapping.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/pagemap.h>
+
+/* ---- Constants and Types ---------------------------------------------- */
+
+/* If DMA_DEBUG_TRACK_RESERVATION is set to a non-zero value, then the filename */
+/* and line number of the reservation request will be recorded in the channel table */
+
+#define DMA_DEBUG_TRACK_RESERVATION 1
+
+#define DMA_NUM_CONTROLLERS 2
+#define DMA_NUM_CHANNELS 8 /* per controller */
+
+typedef enum {
+ DMA_DEVICE_MEM_TO_MEM, /* For memory to memory transfers */
+ DMA_DEVICE_I2S0_DEV_TO_MEM,
+ DMA_DEVICE_I2S0_MEM_TO_DEV,
+ DMA_DEVICE_I2S1_DEV_TO_MEM,
+ DMA_DEVICE_I2S1_MEM_TO_DEV,
+ DMA_DEVICE_APM_CODEC_A_DEV_TO_MEM,
+ DMA_DEVICE_APM_CODEC_A_MEM_TO_DEV,
+ DMA_DEVICE_APM_CODEC_B_DEV_TO_MEM,
+ DMA_DEVICE_APM_CODEC_B_MEM_TO_DEV,
+ DMA_DEVICE_APM_CODEC_C_DEV_TO_MEM, /* Additional mic input for beam-forming */
+ DMA_DEVICE_APM_PCM0_DEV_TO_MEM,
+ DMA_DEVICE_APM_PCM0_MEM_TO_DEV,
+ DMA_DEVICE_APM_PCM1_DEV_TO_MEM,
+ DMA_DEVICE_APM_PCM1_MEM_TO_DEV,
+ DMA_DEVICE_SPUM_DEV_TO_MEM,
+ DMA_DEVICE_SPUM_MEM_TO_DEV,
+ DMA_DEVICE_SPIH_DEV_TO_MEM,
+ DMA_DEVICE_SPIH_MEM_TO_DEV,
+ DMA_DEVICE_UART_A_DEV_TO_MEM,
+ DMA_DEVICE_UART_A_MEM_TO_DEV,
+ DMA_DEVICE_UART_B_DEV_TO_MEM,
+ DMA_DEVICE_UART_B_MEM_TO_DEV,
+ DMA_DEVICE_PIF_MEM_TO_DEV,
+ DMA_DEVICE_PIF_DEV_TO_MEM,
+ DMA_DEVICE_ESW_DEV_TO_MEM,
+ DMA_DEVICE_ESW_MEM_TO_DEV,
+ DMA_DEVICE_VPM_MEM_TO_MEM,
+ DMA_DEVICE_CLCD_MEM_TO_MEM,
+ DMA_DEVICE_NAND_MEM_TO_MEM,
+ DMA_DEVICE_MEM_TO_VRAM,
+ DMA_DEVICE_VRAM_TO_MEM,
+
+ /* Add new entries before this line. */
+
+ DMA_NUM_DEVICE_ENTRIES,
+ DMA_DEVICE_NONE = 0xff, /* Special value to indicate that no device is currently assigned. */
+
+} DMA_Device_t;
+
+/****************************************************************************
+*
+* The DMA_Handle_t is the primary object used by callers of the API.
+*
+*****************************************************************************/
+
+#define DMA_INVALID_HANDLE ((DMA_Handle_t) -1)
+
+typedef int DMA_Handle_t;
+
+/****************************************************************************
+*
+* The DMA_DescriptorRing_t contains a ring of descriptors which is used
+* to point to regions of memory.
+*
+*****************************************************************************/
+
+typedef struct {
+ void *virtAddr; /* Virtual Address of the descriptor ring */
+ dma_addr_t physAddr; /* Physical address of the descriptor ring */
+ int descriptorsAllocated; /* Number of descriptors allocated in the descriptor ring */
+ size_t bytesAllocated; /* Number of bytes allocated in the descriptor ring */
+
+} DMA_DescriptorRing_t;
+
+/****************************************************************************
+*
+* The DMA_MemType_t and DMA_MemMap_t are helper structures used to setup
+* DMA chains from a variety of memory sources.
+*
+*****************************************************************************/
+
+#define DMA_MEM_MAP_MIN_SIZE 4096 /* Pages less than this size are better */
+ /* off not being DMA'd. */
+
+typedef enum {
+ DMA_MEM_TYPE_NONE, /* Not a valid setting */
+ DMA_MEM_TYPE_VMALLOC, /* Memory came from vmalloc call */
+ DMA_MEM_TYPE_KMALLOC, /* Memory came from kmalloc call */
+ DMA_MEM_TYPE_DMA, /* Memory came from dma_alloc_xxx call */
+ DMA_MEM_TYPE_USER, /* Memory came from user space. */
+
+} DMA_MemType_t;
+
+/* A segment represents a physically and virtually contiguous chunk of memory. */
+/* i.e. each segment can be DMA'd */
+/* A user of the DMA code will add memory regions. Each region may need to be */
+/* represented by one or more segments. */
+
+typedef struct {
+ void *virtAddr; /* Virtual address used for this segment */
+ dma_addr_t physAddr; /* Physical address this segment maps to */
+ size_t numBytes; /* Size of the segment, in bytes */
+
+} DMA_Segment_t;
+
+/* A region represents a virtually contiguous chunk of memory, which may be */
+/* made up of multiple segments. */
+
+typedef struct {
+ DMA_MemType_t memType;
+ void *virtAddr;
+ size_t numBytes;
+
+ /* Each region (virtually contiguous) consists of one or more segments. Each */
+ /* segment is virtually and physically contiguous. */
+
+ int numSegmentsUsed;
+ int numSegmentsAllocated;
+ DMA_Segment_t *segment;
+
+ /* When a region corresponds to user memory, we need to lock all of the pages */
+ /* down before we can figure out the physical addresses. The lockedPage array contains */
+ /* the pages that were locked, and which subsequently need to be unlocked once the */
+ /* memory is unmapped. */
+
+ unsigned numLockedPages;
+ struct page **lockedPages;
+
+} DMA_Region_t;
+
+typedef struct {
+ int inUse; /* Is this mapping currently being used? */
+ struct semaphore lock; /* Acquired when using this structure */
+ enum dma_data_direction dir; /* Direction this transfer is intended for */
+
+ /* In the event that we're mapping user memory, we need to know which task */
+ /* the memory is for, so that we can obtain the correct mm locks. */
+
+ struct task_struct *userTask;
+
+ int numRegionsUsed;
+ int numRegionsAllocated;
+ DMA_Region_t *region;
+
+} DMA_MemMap_t;
+
+/****************************************************************************
+*
+* The DMA_DeviceAttribute_t contains information which describes a
+* particular DMA device (or peripheral).
+*
+* It is anticipated that the arrary of DMA_DeviceAttribute_t's will be
+* statically initialized.
+*
+*****************************************************************************/
+
+/* The device handler is called whenever a DMA operation completes. The reaon */
+/* for it to be called will be a bitmask with one or more of the following bits */
+/* set. */
+
+#define DMA_HANDLER_REASON_BLOCK_COMPLETE dmacHw_INTERRUPT_STATUS_BLOCK
+#define DMA_HANDLER_REASON_TRANSFER_COMPLETE dmacHw_INTERRUPT_STATUS_TRANS
+#define DMA_HANDLER_REASON_ERROR dmacHw_INTERRUPT_STATUS_ERROR
+
+typedef void (*DMA_DeviceHandler_t) (DMA_Device_t dev, int reason,
+ void *userData);
+
+#define DMA_DEVICE_FLAG_ON_DMA0 0x00000001
+#define DMA_DEVICE_FLAG_ON_DMA1 0x00000002
+#define DMA_DEVICE_FLAG_PORT_PER_DMAC 0x00000004 /* If set, it means that the port used on DMAC0 is different from the port used on DMAC1 */
+#define DMA_DEVICE_FLAG_ALLOC_DMA1_FIRST 0x00000008 /* If set, allocate from DMA1 before allocating from DMA0 */
+#define DMA_DEVICE_FLAG_IS_DEDICATED 0x00000100
+#define DMA_DEVICE_FLAG_NO_ISR 0x00000200
+#define DMA_DEVICE_FLAG_ALLOW_LARGE_FIFO 0x00000400
+#define DMA_DEVICE_FLAG_IN_USE 0x00000800 /* If set, device is in use on a channel */
+
+/* Note: Some DMA devices can be used from multiple DMA Controllers. The bitmask is used to */
+/* determine which DMA controllers a given device can be used from, and the interface */
+/* array determeines the actual interface number to use for a given controller. */
+
+typedef struct {
+ uint32_t flags; /* Bitmask of DMA_DEVICE_FLAG_xxx constants */
+ uint8_t dedicatedController; /* Controller number to use if DMA_DEVICE_FLAG_IS_DEDICATED is set. */
+ uint8_t dedicatedChannel; /* Channel number to use if DMA_DEVICE_FLAG_IS_DEDICATED is set. */
+ const char *name; /* Will show up in the /proc entry */
+
+ uint32_t dmacPort[DMA_NUM_CONTROLLERS]; /* Specifies the port number when DMA_DEVICE_FLAG_PORT_PER_DMAC flag is set */
+
+ dmacHw_CONFIG_t config; /* Configuration to use when DMA'ing using this device */
+
+ void *userData; /* Passed to the devHandler */
+ DMA_DeviceHandler_t devHandler; /* Called when DMA operations finish. */
+
+ timer_tick_count_t transferStartTime; /* Time the current transfer was started */
+
+ /* The following statistical information will be collected and presented in a proc entry. */
+ /* Note: With a contiuous bandwidth of 1 Gb/sec, it would take 584 years to overflow */
+ /* a 64 bit counter. */
+
+ uint64_t numTransfers; /* Number of DMA transfers performed */
+ uint64_t transferTicks; /* Total time spent doing DMA transfers (measured in timer_tick_count_t's) */
+ uint64_t transferBytes; /* Total bytes transferred */
+ uint32_t timesBlocked; /* Number of times a channel was unavailable */
+ uint32_t numBytes; /* Last transfer size */
+
+ /* It's not possible to free memory which is allocated for the descriptors from within */
+ /* the ISR. So make the presumption that a given device will tend to use the */
+ /* same sized buffers over and over again, and we keep them around. */
+
+ DMA_DescriptorRing_t ring; /* Ring of descriptors allocated for this device */
+
+ /* We stash away some of the information from the previous transfer. If back-to-back */
+ /* transfers are performed from the same buffer, then we don't have to keep re-initializing */
+ /* the descriptor buffers. */
+
+ uint32_t prevNumBytes;
+ dma_addr_t prevSrcData;
+ dma_addr_t prevDstData;
+
+} DMA_DeviceAttribute_t;
+
+/****************************************************************************
+*
+* DMA_Channel_t, DMA_Controller_t, and DMA_State_t are really internal
+* data structures and don't belong in this header file, but are included
+* merely for discussion.
+*
+* By the time this is implemented, these structures will be moved out into
+* the appropriate C source file instead.
+*
+*****************************************************************************/
+
+/****************************************************************************
+*
+* The DMA_Channel_t contains state information about each DMA channel. Some
+* of the channels are dedicated. Non-dedicated channels are shared
+* amongst the other devices.
+*
+*****************************************************************************/
+
+#define DMA_CHANNEL_FLAG_IN_USE 0x00000001
+#define DMA_CHANNEL_FLAG_IS_DEDICATED 0x00000002
+#define DMA_CHANNEL_FLAG_NO_ISR 0x00000004
+#define DMA_CHANNEL_FLAG_LARGE_FIFO 0x00000008
+
+typedef struct {
+ uint32_t flags; /* bitmask of DMA_CHANNEL_FLAG_xxx constants */
+ DMA_Device_t devType; /* Device this channel is currently reserved for */
+ DMA_Device_t lastDevType; /* Device type that used this previously */
+ char name[20]; /* Name passed onto request_irq */
+
+#if (DMA_DEBUG_TRACK_RESERVATION)
+ const char *fileName; /* Place where channel reservation took place */
+ int lineNum; /* Place where channel reservation took place */
+#endif
+ dmacHw_HANDLE_t dmacHwHandle; /* low level channel handle. */
+
+} DMA_Channel_t;
+
+/****************************************************************************
+*
+* The DMA_Controller_t contains state information about each DMA controller.
+*
+* The freeChannelQ is stored in the controller data structure rather than
+* the channel data structure since several of the devices are accessible
+* from multiple controllers, and there is no way to know which controller
+* will become available first.
+*
+*****************************************************************************/
+
+typedef struct {
+ DMA_Channel_t channel[DMA_NUM_CHANNELS];
+
+} DMA_Controller_t;
+
+/****************************************************************************
+*
+* The DMA_Global_t contains all of the global state information used by
+* the DMA code.
+*
+* Callers which need to allocate a shared channel will be queued up
+* on the freeChannelQ until a channel becomes available.
+*
+*****************************************************************************/
+
+typedef struct {
+ struct semaphore lock; /* acquired when manipulating table entries */
+ wait_queue_head_t freeChannelQ;
+
+ DMA_Controller_t controller[DMA_NUM_CONTROLLERS];
+
+} DMA_Global_t;
+
+/* ---- Variable Externs ------------------------------------------------- */
+
+extern DMA_DeviceAttribute_t DMA_gDeviceAttribute[DMA_NUM_DEVICE_ENTRIES];
+
+/* ---- Function Prototypes ---------------------------------------------- */
+
+#if defined(__KERNEL__)
+
+/****************************************************************************/
+/**
+* Initializes the DMA module.
+*
+* @return
+* 0 - Success
+* < 0 - Error
+*/
+/****************************************************************************/
+
+int dma_init(void);
+
+#if (DMA_DEBUG_TRACK_RESERVATION)
+DMA_Handle_t dma_request_channel_dbg(DMA_Device_t dev, const char *fileName,
+ int lineNum);
+#define dma_request_channel(dev) dma_request_channel_dbg(dev, __FILE__, __LINE__)
+#else
+
+/****************************************************************************/
+/**
+* Reserves a channel for use with @a dev. If the device is setup to use
+* a shared channel, then this function will block until a free channel
+* becomes available.
+*
+* @return
+* >= 0 - A valid DMA Handle.
+* -EBUSY - Device is currently being used.
+* -ENODEV - Device handed in is invalid.
+*/
+/****************************************************************************/
+
+DMA_Handle_t dma_request_channel(DMA_Device_t dev /* Device to use with the allocated channel. */
+ );
+#endif
+
+/****************************************************************************/
+/**
+* Frees a previously allocated DMA Handle.
+*
+* @return
+* 0 - DMA Handle was released successfully.
+* -EINVAL - Invalid DMA handle
+*/
+/****************************************************************************/
+
+int dma_free_channel(DMA_Handle_t channel /* DMA handle. */
+ );
+
+/****************************************************************************/
+/**
+* Determines if a given device has been configured as using a shared
+* channel.
+*
+* @return boolean
+* 0 Device uses a dedicated channel
+* non-zero Device uses a shared channel
+*/
+/****************************************************************************/
+
+int dma_device_is_channel_shared(DMA_Device_t dev /* Device to check. */
+ );
+
+/****************************************************************************/
+/**
+* Allocates memory to hold a descriptor ring. The descriptor ring then
+* needs to be populated by making one or more calls to
+* dna_add_descriptors.
+*
+* The returned descriptor ring will be automatically initialized.
+*
+* @return
+* 0 Descriptor ring was allocated successfully
+* -ENOMEM Unable to allocate memory for the desired number of descriptors.
+*/
+/****************************************************************************/
+
+int dma_alloc_descriptor_ring(DMA_DescriptorRing_t *ring, /* Descriptor ring to populate */
+ int numDescriptors /* Number of descriptors that need to be allocated. */
+ );
+
+/****************************************************************************/
+/**
+* Releases the memory which was previously allocated for a descriptor ring.
+*/
+/****************************************************************************/
+
+void dma_free_descriptor_ring(DMA_DescriptorRing_t *ring /* Descriptor to release */
+ );
+
+/****************************************************************************/
+/**
+* Initializes a descriptor ring, so that descriptors can be added to it.
+* Once a descriptor ring has been allocated, it may be reinitialized for
+* use with additional/different regions of memory.
+*
+* Note that if 7 descriptors are allocated, it's perfectly acceptable to
+* initialize the ring with a smaller number of descriptors. The amount
+* of memory allocated for the descriptor ring will not be reduced, and
+* the descriptor ring may be reinitialized later
+*
+* @return
+* 0 Descriptor ring was initialized successfully
+* -ENOMEM The descriptor which was passed in has insufficient space
+* to hold the desired number of descriptors.
+*/
+/****************************************************************************/
+
+int dma_init_descriptor_ring(DMA_DescriptorRing_t *ring, /* Descriptor ring to initialize */
+ int numDescriptors /* Number of descriptors to initialize. */
+ );
+
+/****************************************************************************/
+/**
+* Determines the number of descriptors which would be required for a
+* transfer of the indicated memory region.
+*
+* This function also needs to know which DMA device this transfer will
+* be destined for, so that the appropriate DMA configuration can be retrieved.
+* DMA parameters such as transfer width, and whether this is a memory-to-memory
+* or memory-to-peripheral, etc can all affect the actual number of descriptors
+* required.
+*
+* @return
+* > 0 Returns the number of descriptors required for the indicated transfer
+* -EINVAL Invalid device type for this kind of transfer
+* (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
+* -ENOMEM Memory exhausted
+*/
+/****************************************************************************/
+
+int dma_calculate_descriptor_count(DMA_Device_t device, /* DMA Device that this will be associated with */
+ dma_addr_t srcData, /* Place to get data to write to device */
+ dma_addr_t dstData, /* Pointer to device data address */
+ size_t numBytes /* Number of bytes to transfer to the device */
+ );
+
+/****************************************************************************/
+/**
+* Adds a region of memory to the descriptor ring. Note that it may take
+* multiple descriptors for each region of memory. It is the callers
+* responsibility to allocate a sufficiently large descriptor ring.
+*
+* @return
+* 0 Descriptors were added successfully
+* -EINVAL Invalid device type for this kind of transfer
+* (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
+* -ENOMEM Memory exhausted
+*/
+/****************************************************************************/
+
+int dma_add_descriptors(DMA_DescriptorRing_t *ring, /* Descriptor ring to add descriptors to */
+ DMA_Device_t device, /* DMA Device that descriptors are for */
+ dma_addr_t srcData, /* Place to get data (memory or device) */
+ dma_addr_t dstData, /* Place to put data (memory or device) */
+ size_t numBytes /* Number of bytes to transfer to the device */
+ );
+
+/****************************************************************************/
+/**
+* Sets the descriptor ring associated with a device.
+*
+* Once set, the descriptor ring will be associated with the device, even
+* across channel request/free calls. Passing in a NULL descriptor ring
+* will release any descriptor ring currently associated with the device.
+*
+* Note: If you call dma_transfer, or one of the other dma_alloc_ functions
+* the descriptor ring may be released and reallocated.
+*
+* Note: This function will release the descriptor memory for any current
+* descriptor ring associated with this device.
+*/
+/****************************************************************************/
+
+int dma_set_device_descriptor_ring(DMA_Device_t device, /* Device to update the descriptor ring for. */
+ DMA_DescriptorRing_t *ring /* Descriptor ring to add descriptors to */
+ );
+
+/****************************************************************************/
+/**
+* Retrieves the descriptor ring associated with a device.
+*/
+/****************************************************************************/
+
+int dma_get_device_descriptor_ring(DMA_Device_t device, /* Device to retrieve the descriptor ring for. */
+ DMA_DescriptorRing_t *ring /* Place to store retrieved ring */
+ );
+
+/****************************************************************************/
+/**
+* Allocates buffers for the descriptors. This is normally done automatically
+* but needs to be done explicitly when initiating a dma from interrupt
+* context.
+*
+* @return
+* 0 Descriptors were allocated successfully
+* -EINVAL Invalid device type for this kind of transfer
+* (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
+* -ENOMEM Memory exhausted
+*/
+/****************************************************************************/
+
+int dma_alloc_descriptors(DMA_Handle_t handle, /* DMA Handle */
+ dmacHw_TRANSFER_TYPE_e transferType, /* Type of transfer being performed */
+ dma_addr_t srcData, /* Place to get data to write to device */
+ dma_addr_t dstData, /* Pointer to device data address */
+ size_t numBytes /* Number of bytes to transfer to the device */
+ );
+
+/****************************************************************************/
+/**
+* Allocates and sets up descriptors for a double buffered circular buffer.
+*
+* This is primarily intended to be used for things like the ingress samples
+* from a microphone.
+*
+* @return
+* > 0 Number of descriptors actually allocated.
+* -EINVAL Invalid device type for this kind of transfer
+* (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
+* -ENOMEM Memory exhausted
+*/
+/****************************************************************************/
+
+int dma_alloc_double_dst_descriptors(DMA_Handle_t handle, /* DMA Handle */
+ dma_addr_t srcData, /* Physical address of source data */
+ dma_addr_t dstData1, /* Physical address of first destination buffer */
+ dma_addr_t dstData2, /* Physical address of second destination buffer */
+ size_t numBytes /* Number of bytes in each destination buffer */
+ );
+
+/****************************************************************************/
+/**
+* Initializes a DMA_MemMap_t data structure
+*/
+/****************************************************************************/
+
+int dma_init_mem_map(DMA_MemMap_t *memMap /* Stores state information about the map */
+ );
+
+/****************************************************************************/
+/**
+* Releases any memory currently being held by a memory mapping structure.
+*/
+/****************************************************************************/
+
+int dma_term_mem_map(DMA_MemMap_t *memMap /* Stores state information about the map */
+ );
+
+/****************************************************************************/
+/**
+* Looks at a memory address and categorizes it.
+*
+* @return One of the values from the DMA_MemType_t enumeration.
+*/
+/****************************************************************************/
+
+DMA_MemType_t dma_mem_type(void *addr);
+
+/****************************************************************************/
+/**
+* Sets the process (aka userTask) associated with a mem map. This is
+* required if user-mode segments will be added to the mapping.
+*/
+/****************************************************************************/
+
+static inline void dma_mem_map_set_user_task(DMA_MemMap_t *memMap,
+ struct task_struct *task)
+{
+ memMap->userTask = task;
+}
+
+/****************************************************************************/
+/**
+* Looks at a memory address and determines if we support DMA'ing to/from
+* that type of memory.
+*
+* @return boolean -
+* return value != 0 means dma supported
+* return value == 0 means dma not supported
+*/
+/****************************************************************************/
+
+int dma_mem_supports_dma(void *addr);
+
+/****************************************************************************/
+/**
+* Initializes a memory map for use. Since this function acquires a
+* sempaphore within the memory map, it is VERY important that dma_unmap
+* be called when you're finished using the map.
+*/
+/****************************************************************************/
+
+int dma_map_start(DMA_MemMap_t *memMap, /* Stores state information about the map */
+ enum dma_data_direction dir /* Direction that the mapping will be going */
+ );
+
+/****************************************************************************/
+/**
+* Adds a segment of memory to a memory map.
+*
+* @return 0 on success, error code otherwise.
+*/
+/****************************************************************************/
+
+int dma_map_add_region(DMA_MemMap_t *memMap, /* Stores state information about the map */
+ void *mem, /* Virtual address that we want to get a map of */
+ size_t numBytes /* Number of bytes being mapped */
+ );
+
+/****************************************************************************/
+/**
+* Creates a descriptor ring from a memory mapping.
+*
+* @return 0 on sucess, error code otherwise.
+*/
+/****************************************************************************/
+
+int dma_map_create_descriptor_ring(DMA_Device_t dev, /* DMA device (where the ring is stored) */
+ DMA_MemMap_t *memMap, /* Memory map that will be used */
+ dma_addr_t devPhysAddr /* Physical address of device */
+ );
+
+/****************************************************************************/
+/**
+* Maps in a memory region such that it can be used for performing a DMA.
+*
+* @return
+*/
+/****************************************************************************/
+
+int dma_map_mem(DMA_MemMap_t *memMap, /* Stores state information about the map */
+ void *addr, /* Virtual address that we want to get a map of */
+ size_t count, /* Number of bytes being mapped */
+ enum dma_data_direction dir /* Direction that the mapping will be going */
+ );
+
+/****************************************************************************/
+/**
+* Maps in a memory region such that it can be used for performing a DMA.
+*
+* @return
+*/
+/****************************************************************************/
+
+int dma_unmap(DMA_MemMap_t *memMap, /* Stores state information about the map */
+ int dirtied /* non-zero if any of the pages were modified */
+ );
+
+/****************************************************************************/
+/**
+* Initiates a transfer when the descriptors have already been setup.
+*
+* This is a special case, and normally, the dma_transfer_xxx functions should
+* be used.
+*
+* @return
+* 0 Transfer was started successfully
+* -ENODEV Invalid handle
+*/
+/****************************************************************************/
+
+int dma_start_transfer(DMA_Handle_t handle);
+
+/****************************************************************************/
+/**
+* Stops a previously started DMA transfer.
+*
+* @return
+* 0 Transfer was stopped successfully
+* -ENODEV Invalid handle
+*/
+/****************************************************************************/
+
+int dma_stop_transfer(DMA_Handle_t handle);
+
+/****************************************************************************/
+/**
+* Waits for a DMA to complete by polling. This function is only intended
+* to be used for testing. Interrupts should be used for most DMA operations.
+*/
+/****************************************************************************/
+
+int dma_wait_transfer_done(DMA_Handle_t handle);
+
+/****************************************************************************/
+/**
+* Initiates a DMA transfer
+*
+* @return
+* 0 Transfer was started successfully
+* -EINVAL Invalid device type for this kind of transfer
+* (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
+*/
+/****************************************************************************/
+
+int dma_transfer(DMA_Handle_t handle, /* DMA Handle */
+ dmacHw_TRANSFER_TYPE_e transferType, /* Type of transfer being performed */
+ dma_addr_t srcData, /* Place to get data to write to device */
+ dma_addr_t dstData, /* Pointer to device data address */
+ size_t numBytes /* Number of bytes to transfer to the device */
+ );
+
+/****************************************************************************/
+/**
+* Initiates a transfer from memory to a device.
+*
+* @return
+* 0 Transfer was started successfully
+* -EINVAL Invalid device type for this kind of transfer
+* (i.e. the device is _DEV_TO_MEM and not _MEM_TO_DEV)
+*/
+/****************************************************************************/
+
+static inline int dma_transfer_to_device(DMA_Handle_t handle, /* DMA Handle */
+ dma_addr_t srcData, /* Place to get data to write to device (physical address) */
+ dma_addr_t dstData, /* Pointer to device data address (physical address) */
+ size_t numBytes /* Number of bytes to transfer to the device */
+ ) {
+ return dma_transfer(handle,
+ dmacHw_TRANSFER_TYPE_MEM_TO_PERIPHERAL,
+ srcData, dstData, numBytes);
+}
+
+/****************************************************************************/
+/**
+* Initiates a transfer from a device to memory.
+*
+* @return
+* 0 Transfer was started successfully
+* -EINVAL Invalid device type for this kind of transfer
+* (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
+*/
+/****************************************************************************/
+
+static inline int dma_transfer_from_device(DMA_Handle_t handle, /* DMA Handle */
+ dma_addr_t srcData, /* Pointer to the device data address (physical address) */
+ dma_addr_t dstData, /* Place to store data retrieved from the device (physical address) */
+ size_t numBytes /* Number of bytes to retrieve from the device */
+ ) {
+ return dma_transfer(handle,
+ dmacHw_TRANSFER_TYPE_PERIPHERAL_TO_MEM,
+ srcData, dstData, numBytes);
+}
+
+/****************************************************************************/
+/**
+* Initiates a memory to memory transfer.
+*
+* @return
+* 0 Transfer was started successfully
+* -EINVAL Invalid device type for this kind of transfer
+* (i.e. the device wasn't DMA_DEVICE_MEM_TO_MEM)
+*/
+/****************************************************************************/
+
+static inline int dma_transfer_mem_to_mem(DMA_Handle_t handle, /* DMA Handle */
+ dma_addr_t srcData, /* Place to transfer data from (physical address) */
+ dma_addr_t dstData, /* Place to transfer data to (physical address) */
+ size_t numBytes /* Number of bytes to transfer */
+ ) {
+ return dma_transfer(handle,
+ dmacHw_TRANSFER_TYPE_MEM_TO_MEM,
+ srcData, dstData, numBytes);
+}
+
+/****************************************************************************/
+/**
+* Set the callback function which will be called when a transfer completes.
+* If a NULL callback function is set, then no callback will occur.
+*
+* @note @a devHandler will be called from IRQ context.
+*
+* @return
+* 0 - Success
+* -ENODEV - Device handed in is invalid.
+*/
+/****************************************************************************/
+
+int dma_set_device_handler(DMA_Device_t dev, /* Device to set the callback for. */
+ DMA_DeviceHandler_t devHandler, /* Function to call when the DMA completes */
+ void *userData /* Pointer which will be passed to devHandler. */
+ );
+
+#endif
+
+#endif /* ASM_ARM_ARCH_BCMRING_DMA_H */