diff options
Diffstat (limited to 'arch/arm/mach-bcmring/dma.c')
| -rw-r--r-- | arch/arm/mach-bcmring/dma.c | 812 |
1 files changed, 0 insertions, 812 deletions
diff --git a/arch/arm/mach-bcmring/dma.c b/arch/arm/mach-bcmring/dma.c index 1a1a27d..1024396 100644 --- a/arch/arm/mach-bcmring/dma.c +++ b/arch/arm/mach-bcmring/dma.c @@ -33,17 +33,11 @@ #include <mach/timer.h> -#include <linux/mm.h> #include <linux/pfn.h> #include <linux/atomic.h> #include <linux/sched.h> #include <mach/dma.h> -/* I don't quite understand why dc4 fails when this is set to 1 and DMA is enabled */ -/* especially since dc4 doesn't use kmalloc'd memory. */ - -#define ALLOW_MAP_OF_KMALLOC_MEMORY 0 - /* ---- Public Variables ------------------------------------------------- */ /* ---- Private Constants and Types -------------------------------------- */ @@ -53,24 +47,12 @@ #define CONTROLLER_FROM_HANDLE(handle) (((handle) >> 4) & 0x0f) #define CHANNEL_FROM_HANDLE(handle) ((handle) & 0x0f) -#define DMA_MAP_DEBUG 0 - -#if DMA_MAP_DEBUG -# define DMA_MAP_PRINT(fmt, args...) printk("%s: " fmt, __func__, ## args) -#else -# define DMA_MAP_PRINT(fmt, args...) -#endif /* ---- Private Variables ------------------------------------------------ */ static DMA_Global_t gDMA; static struct proc_dir_entry *gDmaDir; -static atomic_t gDmaStatMemTypeKmalloc = ATOMIC_INIT(0); -static atomic_t gDmaStatMemTypeVmalloc = ATOMIC_INIT(0); -static atomic_t gDmaStatMemTypeUser = ATOMIC_INIT(0); -static atomic_t gDmaStatMemTypeCoherent = ATOMIC_INIT(0); - #include "dma_device.c" /* ---- Private Function Prototypes -------------------------------------- */ @@ -79,34 +61,6 @@ static atomic_t gDmaStatMemTypeCoherent = ATOMIC_INIT(0); /****************************************************************************/ /** -* Displays information for /proc/dma/mem-type -*/ -/****************************************************************************/ - -static int dma_proc_read_mem_type(char *buf, char **start, off_t offset, - int count, int *eof, void *data) -{ - int len = 0; - - len += sprintf(buf + len, "dma_map_mem statistics\n"); - len += - sprintf(buf + len, "coherent: %d\n", - atomic_read(&gDmaStatMemTypeCoherent)); - len += - sprintf(buf + len, "kmalloc: %d\n", - atomic_read(&gDmaStatMemTypeKmalloc)); - len += - sprintf(buf + len, "vmalloc: %d\n", - atomic_read(&gDmaStatMemTypeVmalloc)); - len += - sprintf(buf + len, "user: %d\n", - atomic_read(&gDmaStatMemTypeUser)); - - return len; -} - -/****************************************************************************/ -/** * Displays information for /proc/dma/channels */ /****************************************************************************/ @@ -846,8 +800,6 @@ int dma_init(void) dma_proc_read_channels, NULL); create_proc_read_entry("devices", 0, gDmaDir, dma_proc_read_devices, NULL); - create_proc_read_entry("mem-type", 0, gDmaDir, - dma_proc_read_mem_type, NULL); } out: @@ -1565,767 +1517,3 @@ int dma_set_device_handler(DMA_Device_t dev, /* Device to set the callback for. } EXPORT_SYMBOL(dma_set_device_handler); - -/****************************************************************************/ -/** -* Initializes a memory mapping structure -*/ -/****************************************************************************/ - -int dma_init_mem_map(DMA_MemMap_t *memMap) -{ - memset(memMap, 0, sizeof(*memMap)); - - sema_init(&memMap->lock, 1); - - return 0; -} - -EXPORT_SYMBOL(dma_init_mem_map); - -/****************************************************************************/ -/** -* Releases any memory currently being held by a memory mapping structure. -*/ -/****************************************************************************/ - -int dma_term_mem_map(DMA_MemMap_t *memMap) -{ - down(&memMap->lock); /* Just being paranoid */ - - /* Free up any allocated memory */ - - up(&memMap->lock); - memset(memMap, 0, sizeof(*memMap)); - - return 0; -} - -EXPORT_SYMBOL(dma_term_mem_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) -{ - unsigned long addrVal = (unsigned long)addr; - - if (addrVal >= CONSISTENT_BASE) { - /* NOTE: DMA virtual memory space starts at 0xFFxxxxxx */ - - /* dma_alloc_xxx pages are physically and virtually contiguous */ - - return DMA_MEM_TYPE_DMA; - } - - /* Technically, we could add one more classification. Addresses between VMALLOC_END */ - /* and the beginning of the DMA virtual address could be considered to be I/O space. */ - /* Right now, nobody cares about this particular classification, so we ignore it. */ - - if (is_vmalloc_addr(addr)) { - /* Address comes from the vmalloc'd region. Pages are virtually */ - /* contiguous but NOT physically contiguous */ - - return DMA_MEM_TYPE_VMALLOC; - } - - if (addrVal >= PAGE_OFFSET) { - /* PAGE_OFFSET is typically 0xC0000000 */ - - /* kmalloc'd pages are physically contiguous */ - - return DMA_MEM_TYPE_KMALLOC; - } - - return DMA_MEM_TYPE_USER; -} - -EXPORT_SYMBOL(dma_mem_type); - -/****************************************************************************/ -/** -* 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) -{ - DMA_MemType_t memType = dma_mem_type(addr); - - return (memType == DMA_MEM_TYPE_DMA) -#if ALLOW_MAP_OF_KMALLOC_MEMORY - || (memType == DMA_MEM_TYPE_KMALLOC) -#endif - || (memType == DMA_MEM_TYPE_USER); -} - -EXPORT_SYMBOL(dma_mem_supports_dma); - -/****************************************************************************/ -/** -* Maps in a memory region such that it can be used for performing a DMA. -* -* @return -*/ -/****************************************************************************/ - -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 */ - ) { - int rc; - - down(&memMap->lock); - - DMA_MAP_PRINT("memMap: %p\n", memMap); - - if (memMap->inUse) { - printk(KERN_ERR "%s: memory map %p is already being used\n", - __func__, memMap); - rc = -EBUSY; - goto out; - } - - memMap->inUse = 1; - memMap->dir = dir; - memMap->numRegionsUsed = 0; - - rc = 0; - -out: - - DMA_MAP_PRINT("returning %d", rc); - - up(&memMap->lock); - - return rc; -} - -EXPORT_SYMBOL(dma_map_start); - -/****************************************************************************/ -/** -* Adds a segment of memory to a memory map. Each segment is both -* physically and virtually contiguous. -* -* @return 0 on success, error code otherwise. -*/ -/****************************************************************************/ - -static int dma_map_add_segment(DMA_MemMap_t *memMap, /* Stores state information about the map */ - DMA_Region_t *region, /* Region that the segment belongs to */ - void *virtAddr, /* Virtual address of the segment being added */ - dma_addr_t physAddr, /* Physical address of the segment being added */ - size_t numBytes /* Number of bytes of the segment being added */ - ) { - DMA_Segment_t *segment; - - DMA_MAP_PRINT("memMap:%p va:%p pa:0x%x #:%d\n", memMap, virtAddr, - physAddr, numBytes); - - /* Sanity check */ - - if (((unsigned long)virtAddr < (unsigned long)region->virtAddr) - || (((unsigned long)virtAddr + numBytes)) > - ((unsigned long)region->virtAddr + region->numBytes)) { - printk(KERN_ERR - "%s: virtAddr %p is outside region @ %p len: %d\n", - __func__, virtAddr, region->virtAddr, region->numBytes); - return -EINVAL; - } - - if (region->numSegmentsUsed > 0) { - /* Check to see if this segment is physically contiguous with the previous one */ - - segment = ®ion->segment[region->numSegmentsUsed - 1]; - - if ((segment->physAddr + segment->numBytes) == physAddr) { - /* It is - just add on to the end */ - - DMA_MAP_PRINT("appending %d bytes to last segment\n", - numBytes); - - segment->numBytes += numBytes; - - return 0; - } - } - - /* Reallocate to hold more segments, if required. */ - - if (region->numSegmentsUsed >= region->numSegmentsAllocated) { - DMA_Segment_t *newSegment; - size_t oldSize = - region->numSegmentsAllocated * sizeof(*newSegment); - int newAlloc = region->numSegmentsAllocated + 4; - size_t newSize = newAlloc * sizeof(*newSegment); - - newSegment = kmalloc(newSize, GFP_KERNEL); - if (newSegment == NULL) { - return -ENOMEM; - } - memcpy(newSegment, region->segment, oldSize); - memset(&((uint8_t *) newSegment)[oldSize], 0, - newSize - oldSize); - kfree(region->segment); - - region->numSegmentsAllocated = newAlloc; - region->segment = newSegment; - } - - segment = ®ion->segment[region->numSegmentsUsed]; - region->numSegmentsUsed++; - - segment->virtAddr = virtAddr; - segment->physAddr = physAddr; - segment->numBytes = numBytes; - - DMA_MAP_PRINT("returning success\n"); - - return 0; -} - -/****************************************************************************/ -/** -* Adds a region of memory to a memory map. Each region is virtually -* contiguous, but not necessarily physically contiguous. -* -* @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 */ - ) { - unsigned long addr = (unsigned long)mem; - unsigned int offset; - int rc = 0; - DMA_Region_t *region; - dma_addr_t physAddr; - - down(&memMap->lock); - - DMA_MAP_PRINT("memMap:%p va:%p #:%d\n", memMap, mem, numBytes); - - if (!memMap->inUse) { - printk(KERN_ERR "%s: Make sure you call dma_map_start first\n", - __func__); - rc = -EINVAL; - goto out; - } - - /* Reallocate to hold more regions. */ - - if (memMap->numRegionsUsed >= memMap->numRegionsAllocated) { - DMA_Region_t *newRegion; - size_t oldSize = - memMap->numRegionsAllocated * sizeof(*newRegion); - int newAlloc = memMap->numRegionsAllocated + 4; - size_t newSize = newAlloc * sizeof(*newRegion); - - newRegion = kmalloc(newSize, GFP_KERNEL); - if (newRegion == NULL) { - rc = -ENOMEM; - goto out; - } - memcpy(newRegion, memMap->region, oldSize); - memset(&((uint8_t *) newRegion)[oldSize], 0, newSize - oldSize); - - kfree(memMap->region); - - memMap->numRegionsAllocated = newAlloc; - memMap->region = newRegion; - } - - region = &memMap->region[memMap->numRegionsUsed]; - memMap->numRegionsUsed++; - - offset = addr & ~PAGE_MASK; - - region->memType = dma_mem_type(mem); - region->virtAddr = mem; - region->numBytes = numBytes; - region->numSegmentsUsed = 0; - region->numLockedPages = 0; - region->lockedPages = NULL; - - switch (region->memType) { - case DMA_MEM_TYPE_VMALLOC: - { - atomic_inc(&gDmaStatMemTypeVmalloc); - - /* printk(KERN_ERR "%s: vmalloc'd pages are not supported\n", __func__); */ - - /* vmalloc'd pages are not physically contiguous */ - - rc = -EINVAL; - break; - } - - case DMA_MEM_TYPE_KMALLOC: - { - atomic_inc(&gDmaStatMemTypeKmalloc); - - /* kmalloc'd pages are physically contiguous, so they'll have exactly */ - /* one segment */ - -#if ALLOW_MAP_OF_KMALLOC_MEMORY - physAddr = - dma_map_single(NULL, mem, numBytes, memMap->dir); - rc = dma_map_add_segment(memMap, region, mem, physAddr, - numBytes); -#else - rc = -EINVAL; -#endif - break; - } - - case DMA_MEM_TYPE_DMA: - { - /* dma_alloc_xxx pages are physically contiguous */ - - atomic_inc(&gDmaStatMemTypeCoherent); - - physAddr = (vmalloc_to_pfn(mem) << PAGE_SHIFT) + offset; - - dma_sync_single_for_cpu(NULL, physAddr, numBytes, - memMap->dir); - rc = dma_map_add_segment(memMap, region, mem, physAddr, - numBytes); - break; - } - - case DMA_MEM_TYPE_USER: - { - size_t firstPageOffset; - size_t firstPageSize; - struct page **pages; - struct task_struct *userTask; - - atomic_inc(&gDmaStatMemTypeUser); - -#if 1 - /* If the pages are user pages, then the dma_mem_map_set_user_task function */ - /* must have been previously called. */ - - if (memMap->userTask == NULL) { - printk(KERN_ERR - "%s: must call dma_mem_map_set_user_task when using user-mode memory\n", - __func__); - return -EINVAL; - } - - /* User pages need to be locked. */ - - firstPageOffset = - (unsigned long)region->virtAddr & (PAGE_SIZE - 1); - firstPageSize = PAGE_SIZE - firstPageOffset; - - region->numLockedPages = (firstPageOffset - + region->numBytes + - PAGE_SIZE - 1) / PAGE_SIZE; - pages = - kmalloc(region->numLockedPages * - sizeof(struct page *), GFP_KERNEL); - - if (pages == NULL) { - region->numLockedPages = 0; - return -ENOMEM; - } - - userTask = memMap->userTask; - - down_read(&userTask->mm->mmap_sem); - rc = get_user_pages(userTask, /* task */ - userTask->mm, /* mm */ - (unsigned long)region->virtAddr, /* start */ - region->numLockedPages, /* len */ - memMap->dir == DMA_FROM_DEVICE, /* write */ - 0, /* force */ - pages, /* pages (array of pointers to page) */ - NULL); /* vmas */ - up_read(&userTask->mm->mmap_sem); - - if (rc != region->numLockedPages) { - kfree(pages); - region->numLockedPages = 0; - - if (rc >= 0) { - rc = -EINVAL; - } - } else { - uint8_t *virtAddr = region->virtAddr; - size_t bytesRemaining; - int pageIdx; - - rc = 0; /* Since get_user_pages returns +ve number */ - - region->lockedPages = pages; - - /* We've locked the user pages. Now we need to walk them and figure */ - /* out the physical addresses. */ - - /* The first page may be partial */ - - dma_map_add_segment(memMap, - region, - virtAddr, - PFN_PHYS(page_to_pfn - (pages[0])) + - firstPageOffset, - firstPageSize); - - virtAddr += firstPageSize; - bytesRemaining = - region->numBytes - firstPageSize; - - for (pageIdx = 1; - pageIdx < region->numLockedPages; - pageIdx++) { - size_t bytesThisPage = - (bytesRemaining > - PAGE_SIZE ? PAGE_SIZE : - bytesRemaining); - - DMA_MAP_PRINT - ("pageIdx:%d pages[pageIdx]=%p pfn=%u phys=%u\n", - pageIdx, pages[pageIdx], - page_to_pfn(pages[pageIdx]), - PFN_PHYS(page_to_pfn - (pages[pageIdx]))); - - dma_map_add_segment(memMap, - region, - virtAddr, - PFN_PHYS(page_to_pfn - (pages - [pageIdx])), - bytesThisPage); - - virtAddr += bytesThisPage; - bytesRemaining -= bytesThisPage; - } - } -#else - printk(KERN_ERR - "%s: User mode pages are not yet supported\n", - __func__); - - /* user pages are not physically contiguous */ - - rc = -EINVAL; -#endif - break; - } - - default: - { - printk(KERN_ERR "%s: Unsupported memory type: %d\n", - __func__, region->memType); - - rc = -EINVAL; - break; - } - } - - if (rc != 0) { - memMap->numRegionsUsed--; - } - -out: - - DMA_MAP_PRINT("returning %d\n", rc); - - up(&memMap->lock); - - return rc; -} - -EXPORT_SYMBOL(dma_map_add_segment); - -/****************************************************************************/ -/** -* Maps in a memory region such that it can be used for performing a DMA. -* -* @return 0 on success, error code otherwise. -*/ -/****************************************************************************/ - -int dma_map_mem(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 */ - enum dma_data_direction dir /* Direction that the mapping will be going */ - ) { - int rc; - - rc = dma_map_start(memMap, dir); - if (rc == 0) { - rc = dma_map_add_region(memMap, mem, numBytes); - if (rc < 0) { - /* Since the add fails, this function will fail, and the caller won't */ - /* call unmap, so we need to do it here. */ - - dma_unmap(memMap, 0); - } - } - - return rc; -} - -EXPORT_SYMBOL(dma_map_mem); - -/****************************************************************************/ -/** -* Setup a descriptor ring for a given memory map. -* -* It is assumed that the descriptor ring has already been initialized, and -* this routine will only reallocate a new descriptor ring if the existing -* one is too small. -* -* @return 0 on success, 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 */ - ) { - int rc; - int numDescriptors; - DMA_DeviceAttribute_t *devAttr; - DMA_Region_t *region; - DMA_Segment_t *segment; - dma_addr_t srcPhysAddr; - dma_addr_t dstPhysAddr; - int regionIdx; - int segmentIdx; - - devAttr = &DMA_gDeviceAttribute[dev]; - - down(&memMap->lock); - - /* Figure out how many descriptors we need */ - - numDescriptors = 0; - for (regionIdx = 0; regionIdx < memMap->numRegionsUsed; regionIdx++) { - region = &memMap->region[regionIdx]; - - for (segmentIdx = 0; segmentIdx < region->numSegmentsUsed; - segmentIdx++) { - segment = ®ion->segment[segmentIdx]; - - if (memMap->dir == DMA_TO_DEVICE) { - srcPhysAddr = segment->physAddr; - dstPhysAddr = devPhysAddr; - } else { - srcPhysAddr = devPhysAddr; - dstPhysAddr = segment->physAddr; - } - - rc = - dma_calculate_descriptor_count(dev, srcPhysAddr, - dstPhysAddr, - segment-> - numBytes); - if (rc < 0) { - printk(KERN_ERR - "%s: dma_calculate_descriptor_count failed: %d\n", - __func__, rc); - goto out; - } - numDescriptors += rc; - } - } - - /* Adjust the size of the ring, if it isn't big enough */ - - if (numDescriptors > devAttr->ring.descriptorsAllocated) { - dma_free_descriptor_ring(&devAttr->ring); - rc = - dma_alloc_descriptor_ring(&devAttr->ring, - numDescriptors); - if (rc < 0) { - printk(KERN_ERR - "%s: dma_alloc_descriptor_ring failed: %d\n", - __func__, rc); - goto out; - } - } else { - rc = - dma_init_descriptor_ring(&devAttr->ring, - numDescriptors); - if (rc < 0) { - printk(KERN_ERR - "%s: dma_init_descriptor_ring failed: %d\n", - __func__, rc); - goto out; - } - } - - /* Populate the descriptors */ - - for (regionIdx = 0; regionIdx < memMap->numRegionsUsed; regionIdx++) { - region = &memMap->region[regionIdx]; - - for (segmentIdx = 0; segmentIdx < region->numSegmentsUsed; - segmentIdx++) { - segment = ®ion->segment[segmentIdx]; - - if (memMap->dir == DMA_TO_DEVICE) { - srcPhysAddr = segment->physAddr; - dstPhysAddr = devPhysAddr; - } else { - srcPhysAddr = devPhysAddr; - dstPhysAddr = segment->physAddr; - } - - rc = - dma_add_descriptors(&devAttr->ring, dev, - srcPhysAddr, dstPhysAddr, - segment->numBytes); - if (rc < 0) { - printk(KERN_ERR - "%s: dma_add_descriptors failed: %d\n", - __func__, rc); - goto out; - } - } - } - - rc = 0; - -out: - - up(&memMap->lock); - return rc; -} - -EXPORT_SYMBOL(dma_map_create_descriptor_ring); - -/****************************************************************************/ -/** -* 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 */ - ) { - - int rc = 0; - int regionIdx; - int segmentIdx; - DMA_Region_t *region; - DMA_Segment_t *segment; - - down(&memMap->lock); - - for (regionIdx = 0; regionIdx < memMap->numRegionsUsed; regionIdx++) { - region = &memMap->region[regionIdx]; - - for (segmentIdx = 0; segmentIdx < region->numSegmentsUsed; - segmentIdx++) { - segment = ®ion->segment[segmentIdx]; - - switch (region->memType) { - case DMA_MEM_TYPE_VMALLOC: - { - printk(KERN_ERR - "%s: vmalloc'd pages are not yet supported\n", - __func__); - rc = -EINVAL; - goto out; - } - - case DMA_MEM_TYPE_KMALLOC: - { -#if ALLOW_MAP_OF_KMALLOC_MEMORY - dma_unmap_single(NULL, - segment->physAddr, - segment->numBytes, - memMap->dir); -#endif - break; - } - - case DMA_MEM_TYPE_DMA: - { - dma_sync_single_for_cpu(NULL, - segment-> - physAddr, - segment-> - numBytes, - memMap->dir); - break; - } - - case DMA_MEM_TYPE_USER: - { - /* Nothing to do here. */ - - break; - } - - default: - { - printk(KERN_ERR - "%s: Unsupported memory type: %d\n", - __func__, region->memType); - rc = -EINVAL; - goto out; - } - } - - segment->virtAddr = NULL; - segment->physAddr = 0; - segment->numBytes = 0; - } - - if (region->numLockedPages > 0) { - int pageIdx; - - /* Some user pages were locked. We need to go and unlock them now. */ - - for (pageIdx = 0; pageIdx < region->numLockedPages; - pageIdx++) { - struct page *page = - region->lockedPages[pageIdx]; - - if (memMap->dir == DMA_FROM_DEVICE) { - SetPageDirty(page); - } - page_cache_release(page); - } - kfree(region->lockedPages); - region->numLockedPages = 0; - region->lockedPages = NULL; - } - - region->memType = DMA_MEM_TYPE_NONE; - region->virtAddr = NULL; - region->numBytes = 0; - region->numSegmentsUsed = 0; - } - memMap->userTask = NULL; - memMap->numRegionsUsed = 0; - memMap->inUse = 0; - -out: - up(&memMap->lock); - - return rc; -} - -EXPORT_SYMBOL(dma_unmap); |
