diff options
Diffstat (limited to 'arch/arm/mach-bcmring/include/mach/dma.h')
| -rw-r--r-- | arch/arm/mach-bcmring/include/mach/dma.h | 826 |
1 files changed, 826 insertions, 0 deletions
diff --git a/arch/arm/mach-bcmring/include/mach/dma.h b/arch/arm/mach-bcmring/include/mach/dma.h new file mode 100644 index 0000000..847980c --- /dev/null +++ b/arch/arm/mach-bcmring/include/mach/dma.h @@ -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 */ |
